1. مقدمه
این سند شرایطی را که باید برای سازگاری دستگاهها با Android 12 رعایت شود، برشمرده است.
استفاده از "MUST"، "MUST NOT"، "REQUIRED"، "SHALL"، "SHALL NOT"، "SHOULD"، "SHOULD NOT"، "Recommended"، "MAY" و "OPTIONAL" طبق IETF است. استاندارد تعریف شده در RFC2119 .
همانطور که در این سند استفاده میشود، «پیادهکننده دستگاه» یا «اجراکننده» شخص یا سازمانی است که راهحل سختافزار/نرمافزاری را با Android 12 توسعه میدهد. «پیادهسازی دستگاه» یا «پیادهسازی» راهحل سختافزار/نرمافزاری است که به این شکل توسعه یافته است.
برای اینکه پیادهسازیهای دستگاه با Android 12 سازگار در نظر گرفته شوند، باید الزامات ارائهشده در این تعریف سازگاری، از جمله هر سندی که از طریق مرجع گنجانده شدهاند، داشته باشند.
در مواردی که این تعریف یا تستهای نرمافزاری توضیح داده شده در بخش 10 بیصدا، مبهم یا ناقص باشد، این مسئولیت اجرای دستگاه است که از سازگاری با پیادهسازیهای موجود اطمینان حاصل کند.
به همین دلیل، پروژه متن باز اندروید هم مرجع و هم پیاده سازی ترجیحی اندروید است. به اجراکنندگان دستگاه اکیداً توصیه میشود که پیادهسازیهای خود را تا حد ممکن بر اساس کد منبع «بالادست» موجود در پروژه منبع باز Android قرار دهند. در حالی که برخی از مؤلفهها میتوانند به صورت فرضی با پیادهسازیهای جایگزین جایگزین شوند، اکیداً توصیه میشود که از این رویه پیروی نکنید، زیرا گذراندن آزمونهای نرمافزار به طور قابلتوجهی دشوارتر میشود. این مسئولیت پیادهکننده است که از سازگاری کامل رفتاری با پیادهسازی استاندارد Android، از جمله و فراتر از مجموعه تست سازگاری اطمینان حاصل کند. در نهایت، توجه داشته باشید که تعویض و اصلاح برخی از اجزا به صراحت توسط این سند ممنوع است.
بسیاری از منابع مرتبط با این سند به طور مستقیم یا غیرمستقیم از Android SDK مشتق شده اند و از نظر عملکردی با اطلاعات موجود در اسناد آن SDK یکسان خواهند بود. در هر موردی که این تعریف سازگاری یا مجموعه تست سازگاری با مستندات SDK مخالف باشد، اسناد SDK معتبر تلقی میشوند. هر گونه جزئیات فنی ارائه شده در منابع مرتبط در سراسر این سند با گنجاندن بخشی از این تعریف سازگاری در نظر گرفته می شود.
1.1 ساختار سند
1.1.1. الزامات بر اساس نوع دستگاه
بخش 2 شامل تمام الزاماتی است که برای یک نوع دستگاه خاص اعمال می شود. هر بخش فرعی از بخش 2 به نوع خاصی از دستگاه اختصاص دارد.
تمام الزامات دیگر، که به طور جهانی برای هر پیاده سازی دستگاه Android اعمال می شود، در بخش های بعد از بخش 2 فهرست شده است. این الزامات به عنوان "نیازهای اصلی" در این سند ذکر شده است.
1.1.2. شناسه مورد نیاز
شناسه مورد نیاز برای الزامات MUST اختصاص داده شده است.
- شناسه فقط برای الزامات MUST اختصاص داده شده است.
- الزامات STRONGLY RECOMMENDED به عنوان [SR] علامت گذاری شده اند اما شناسه اختصاص داده نشده است.
- شناسه شامل موارد زیر است: شناسه نوع دستگاه - شناسه وضعیت - شناسه مورد نیاز (به عنوان مثال C-0-1).
هر شناسه به صورت زیر تعریف می شود:
- شناسه نوع دستگاه (بیشتر را در 2. انواع دستگاه ببینید)
- C: Core (الزاماتی که برای همه پیاده سازی های دستگاه اندروید اعمال می شود)
- H: دستگاه Android Handheld
- T: دستگاه Android TV
- A: پیاده سازی Android Automotive
- W: پیاده سازی Android Watch
- تب: پیاده سازی تبلت اندروید
- شناسه وضعیت
- هنگامی که شرط بدون قید و شرط باشد، این شناسه به عنوان 0 تنظیم می شود.
- وقتی شرط شرطی است، 1 برای شرط اول اختصاص داده می شود و عدد در همان بخش و همان نوع دستگاه، 1 افزایش می یابد.
- شناسه مورد نیاز
- این شناسه از 1 شروع می شود و در همان بخش و شرایط یکسان 1 افزایش می یابد.
1.1.3. شناسه مورد نیاز در بخش 2
شناسه های مورد نیاز در بخش 2 دارای دو بخش هستند. اولین مورد مربوط به شناسه بخش همانطور که در بالا توضیح داده شد. بخش دوم فاکتور فرم و نیاز خاص فرم فاکتور را مشخص می کند.
شناسه بخش که با شناسه مورد نیاز شرح داده شده در بالا دنبال می شود.
- شناسه در بخش 2 شامل: شناسه بخش / شناسه نوع دستگاه - شناسه شرایط - شناسه مورد نیاز (به عنوان مثال 7.4.3/A-0-1).
2. انواع دستگاه
پروژه منبع باز Android یک پشته نرم افزاری را ارائه می دهد که می تواند برای انواع مختلف دستگاه ها و عوامل شکل استفاده شود. برای پشتیبانی از امنیت در دستگاهها، انتظار میرود پشته نرمافزار، از جمله هر سیستمعامل جایگزین یا اجرای هسته جایگزین، در یک محیط امن همانطور که در بخش 9 و جاهای دیگر این CDD توضیح داده شده است اجرا شود. چند نوع دستگاه وجود دارد که اکوسیستم توزیع کاربرد نسبتاً بهتری دارند.
این بخش انواع دستگاه ها و الزامات و توصیه های اضافی قابل اجرا برای هر نوع دستگاه را شرح می دهد.
همه پیادهسازیهای دستگاه Android که در هیچ یک از انواع دستگاههای توصیفشده قرار نمیگیرند، باید همچنان همه الزامات موجود در بخشهای دیگر این تعریف سازگاری را برآورده کنند.
2.1 تنظیمات دستگاه
برای تفاوتهای عمده در پیکربندی سختافزار بر اساس نوع دستگاه، الزامات خاص دستگاه را که در این بخش دنبال میشود، ببینید.
2.2. الزامات دستی
دستگاه Android Handheld به یک پیاده سازی دستگاه اندرویدی اشاره دارد که معمولاً با نگه داشتن آن در دست استفاده می شود، مانند پخش کننده mp3، تلفن یا تبلت.
پیادهسازیهای دستگاه اندروید در صورتی که تمام معیارهای زیر را داشته باشند به عنوان دستی طبقهبندی میشوند:
- منبع تغذیه ای داشته باشید که تحرک را فراهم می کند، مانند باتری.
- اندازه صفحه نمایش مورب فیزیکی در محدوده 3.3 اینچ (یا 2.5 اینچ برای پیاده سازی دستگاهی که در سطح API 29 یا قبل از آن عرضه شده است) تا 8 اینچ داشته باشید.
الزامات اضافی در بقیه این بخش مختص پیاده سازی دستگاه Android Handheld است.
2.2.1. سخت افزار
پیاده سازی دستگاه های دستی:
- [ 7.1 .1.1/H-0-1] باید حداقل یک نمایشگر سازگار با Android داشته باشد که تمام الزامات توضیح داده شده در این سند را برآورده کند.
[ 7.1 .1.3/H-SR-1] اکیداً توصیه می شود تا امکان تغییر اندازه نمایشگر (تراکم صفحه) را به کاربران ارائه دهند.
[ 7.1 .1.1/H-0-2] باید ترکیب GPU بافرهای گرافیکی را حداقل به اندازه بالاترین وضوح صفحه نمایش داخلی پشتیبانی کند.
اگر پیاده سازی های دستگاه دستی از چرخش صفحه نرم افزار پشتیبانی می کنند، آنها:
- [ 7.1 .1.1/H-1-1]* باید صفحه منطقی را که برای برنامه های شخص ثالث در دسترس است، حداقل 2 اینچ در لبه(های) کوتاه و 2.7 اینچ در لبه(های) بلند قرار دهد. ممکن است دستگاههایی که در Android API سطح 29 یا قبل از آن ارسال شدهاند، از این شرط مستثنی باشند.
اگر پیاده سازی های دستگاه دستی از چرخش صفحه نرم افزار پشتیبانی نمی کنند، آنها:
- [ 7.1 .1.1/H-2-1]* باید صفحه منطقی را که برای برنامه های شخص ثالث در دسترس است، حداقل 2.7 اینچ روی لبه(های) کوتاه قرار دهد. ممکن است دستگاههایی که در Android API سطح 29 یا قبل از آن ارسال شدهاند، از این شرط مستثنی باشند.
اگر پیادهسازیهای دستگاه دستی از طریق Configuration.isScreenHdr()
از نمایشگرهای محدوده دینامیکی بالا پشتیبانی میکنند، آنها:
- [ 7.1 .4.5/H-1-1] باید
VK_EXT_swapchain_colorspace
EGL_EXT_gl_colorspace_bt2020_pq
،EGL_EXT_surface_SMPTE2086_metadata
،EGL_EXT_surface_CTA861_3_metadata
پسوندهایVK_EXT_hdr_metadata
.
پیاده سازی دستگاه های دستی:
- [ 7.1 .4.6/H-0-1] باید گزارش دهد که آیا دستگاه از قابلیت نمایه سازی GPU از طریق ویژگی سیستم
graphics.gpu.profiler.support
پشتیبانی می کند یا خیر.
اگر پیادهسازیهای دستگاه دستی از طریق ویژگی سیستم graphics.gpu.profiler.support
پشتیبانی را اعلام کنند، آنها:
- [ 7.1 .4.6/H-1-1] باید یک ردیابی پروتوباف را به عنوان خروجی گزارش کند که با طرح شمارشگرهای GPU و مراحل پردازش گرافیکی تعریف شده در مستندات Perfetto مطابقت دارد.
- [ 7.1 .4.6/H-1-2] باید مقادیر منطبق را برای شمارندههای GPU دستگاه به دنبال پروتو بسته ردیابی شمارنده gpu گزارش کند.
- [ 7.1 .4.6/H-1-3] باید مقادیر منطبق برای GPU RenderStages دستگاه را به دنبال پروتوی بسته ردیابی مرحله رندر گزارش کند.
- [ 7.1 .4.6/H-1-4] باید یک نقطه ردیابی فرکانس GPU را همانطور که با فرمت مشخص شده گزارش کند: power/gpu_frequency .
پیاده سازی دستگاه های دستی:
- [ 7.1 .5/H-0-1] باید شامل پشتیبانی از حالت سازگاری برنامه های قدیمی همانطور که توسط کد منبع باز بالادستی Android پیاده سازی شده باشد. به این معنا که پیادهسازی دستگاه نباید محرکها یا آستانههایی را که در آن حالت سازگاری فعال میشود، تغییر دهند، و نباید رفتار خود حالت سازگاری را تغییر دهند.
- [ 7.2 .1/H-0-1] باید شامل پشتیبانی از برنامه های کاربردی ویرایشگر روش ورودی (IME) شخص ثالث باشد.
- [ 7.2 .3/H-0-3] باید عملکرد Home را در همه نمایشگرهای سازگار با Android که صفحه اصلی را ارائه می دهند، ارائه دهد.
- [ 7.2 .3/H-0-4] باید عملکرد Back را در همه نمایشگرهای سازگار با Android و عملکرد Recents را در حداقل یکی از نمایشگرهای سازگار با Android ارائه دهد.
- [ 7.2 .3/H-0-2] باید هر دو رویداد فشار عادی و طولانی عملکرد Back (
KEYCODE_BACK
) را به برنامه پیش زمینه ارسال کند. این رویدادها نباید توسط سیستم مصرف شوند و می توانند توسط خارج از دستگاه Android (به عنوان مثال صفحه کلید سخت افزاری خارجی متصل به دستگاه Android) فعال شوند. - [ 7.2.4 /H-0-1] باید از ورودی صفحه لمسی پشتیبانی کند.
- [ 7.2 .4/H-SR-1] برای راهاندازی برنامه کمکی انتخابشده توسط کاربر، به عبارت دیگر برنامهای که VoiceInteractionService یا فعالیتی که
ACTION_ASSIST
را با فشار طولانیKEYCODE_MEDIA_PLAY_PAUSE
یاKEYCODE_HEADSETHOOK
برای فعالیتهای زمینه، اجرا میکند، به شدت توصیه میشود. آن رویدادهای مطبوعاتی طولانی را مدیریت نمی کند. - [ 7.3 .1/H-SR-1] اکیداً توصیه میشود که شتابسنج 3 محوره را در خود جای دهید.
اگر پیاده سازی های دستگاه دستی شامل شتاب سنج 3 محوره باشد، آنها:
- [ 7.3 .1/H-1-1] باید بتواند رویدادها را تا فرکانس حداقل 100 هرتز گزارش کند.
اگر پیادهسازیهای دستگاه دستی شامل گیرنده GPS/GNSS باشد و قابلیت آن را از طریق پرچم ویژگی android.hardware.location.gps
به برنامهها گزارش کند، آنها:
- [ 7.3 .3/H-2-1] باید اندازه گیری های GNSS را به محض یافتن گزارش کند، حتی اگر مکان محاسبه شده از GPS/GNSS هنوز گزارش نشده باشد.
- [ 7.3 0.3/H-2-2] باید مقادیر شبه و نرخ شبه GNSS را گزارش کند، که در شرایط آسمان باز پس از تعیین مکان، در حالی که ساکن یا حرکت با شتاب کمتر از 0.2 متر بر ثانیه مجذور شتاب، برای محاسبه کافی است. موقعیت در 20 متر، و سرعت در 0.2 متر در ثانیه، حداقل 95٪ از زمان.
اگر پیاده سازی های دستگاه دستی شامل یک ژیروسکوپ 3 محوره باشد، آنها:
- [ 7.3 .4/H-3-1] باید بتواند رویدادها را تا فرکانس حداقل 100 هرتز گزارش کند.
- [ 7.3 .4/H-3-2] باید قادر به اندازه گیری تغییرات جهت تا 1000 درجه در ثانیه باشد.
پیاده سازی های دستگاه دستی که می توانند تماس صوتی برقرار کنند و هر مقداری غیر از PHONE_TYPE_NONE
در getPhoneType
نشان دهند:
- [ 7.3 .8/H] باید دارای حسگر مجاورت باشد.
پیاده سازی دستگاه های دستی:
- [ 7.3 .11/H-SR-1] برای پشتیبانی از سنسور پوز با 6 درجه آزادی توصیه می شود.
- [ 7.4 .3/H] باید شامل پشتیبانی از بلوتوث و بلوتوث LE باشد.
اگر پیادهسازیهای دستگاه دستی شامل یک دستگاه دوربین منطقی باشد که قابلیتها را با استفاده از CameraMetadata.REQUEST_AVAILABLE_CAPABILITIES_LOGICAL_MULTI_CAMERA
فهرست میکند.REQUEST_AVAILABLE_CAPABILITIES_LOGICAL_MULTI_CAMERA، آنها:
- [ 7.5 0.4/H-1-1] باید به طور پیش فرض میدان دید طبیعی (FOV) داشته باشد و باید بین 50 تا 95 درجه باشد.
پیاده سازی دستگاه های دستی:
- [ 7.6 .1/H-0-1] باید حداقل 4 گیگابایت فضای ذخیره سازی غیرفرار برای داده های خصوصی برنامه (معروف به پارتیشن "/data") در دسترس باشد.
- [ 7.6 .1/H-0-2] باید برای
ActivityManager.isLowRamDevice()
"true" را زمانی که کمتر از 1 گیگابایت حافظه در اختیار هسته و فضای کاربر وجود دارد، برگرداند.
اگر پیادهسازیهای دستگاه دستی فقط از ABI 32 بیتی پشتیبانی میکنند:
[ 7.6 .1/H-1-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 416 مگابایت باشد اگر نمایشگر پیش فرض از وضوح فریم بافر تا qHD (مثلاً FWVGA) استفاده می کند.
[ 7.6 .1/H-2-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 592 مگابایت باشد اگر نمایشگر پیشفرض از وضوح فریم بافر تا HD+ استفاده میکند (مثلاً HD، WSVGA).
[ 7.6 .1/H-3-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 896 مگابایت باشد اگر صفحه نمایش پیش فرض از وضوح فریم بافر تا FHD استفاده می کند (به عنوان مثال WSXGA+).
[ 7.6 .1/H-4-1] اگر صفحه نمایش پیش فرض از وضوح فریم بافر تا QHD (به عنوان مثال QWXGA) استفاده می کند، حافظه موجود برای هسته و فضای کاربر باید حداقل 1344 مگابایت باشد.
اگر پیادهسازیهای دستگاه دستی از هر ABI 64 بیتی (با یا بدون هیچ ABI 32 بیتی) پشتیبانی میکنند:
[ 7.6 .1/H-5-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 816 مگابایت باشد اگر نمایشگر پیشفرض از وضوح فریم بافر تا qHD (به عنوان مثال FWVGA) استفاده میکند.
[ 7.6 .1/H-6-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 944 مگابایت باشد اگر نمایشگر پیشفرض از وضوح فریم بافر تا HD+ استفاده میکند (مثلاً HD، WSVGA).
[ 7.6 .1/H-7-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 1280 مگابایت باشد اگر صفحه نمایش پیش فرض از وضوح فریم بافر تا FHD استفاده می کند (به عنوان مثال WSXGA+).
[ 7.6 .1/H-8-1] حافظه موجود برای هسته و فضای کاربر باید حداقل 1824 مگابایت باشد اگر صفحه نمایش پیش فرض از وضوح فریم بافر تا QHD (مثلا QWXGA) استفاده می کند.
توجه داشته باشید که "حافظه در دسترس برای هسته و فضای کاربر" در بالا به فضای حافظه ارائه شده به اضافه هر حافظه ای که قبلاً به اجزای سخت افزاری مانند رادیو، ویدئو و غیره اختصاص داده شده است که در پیاده سازی های دستگاه تحت کنترل هسته نیستند، اشاره دارد.
اگر پیادهسازیهای دستگاه دستی شامل کمتر یا مساوی 1 گیگابایت حافظه در دسترس هسته و فضای کاربر باشد، آنها:
- [ 7.6 .1/H-9-1] باید پرچم ویژگی
android.hardware.ram.low
را اعلام کند. - [ 7.6 .1/H-9-2] باید حداقل 1.1 گیگابایت فضای ذخیره سازی غیر فرار برای داده های خصوصی برنامه (معروف به پارتیشن "/data") داشته باشد.
اگر پیاده سازی های دستگاه دستی شامل بیش از 1 گیگابایت حافظه در دسترس هسته و فضای کاربر باشد، آنها:
- [ 7.6 .1/H-10-1] باید حداقل 4 گیگابایت فضای ذخیره سازی غیر فرار برای داده های خصوصی برنامه (معروف به پارتیشن "/data") در دسترس باشد.
- باید پرچم ویژگی
android.hardware.ram.normal
را اعلام کند.
اگر پیادهسازیهای دستگاه دستی شامل حافظه بیشتر یا مساوی 2 گیگابایت و کمتر از 4 گیگابایت در اختیار هسته و فضای کاربر باشد، آنها:
- [7.6.1/H-SR-1] اکیداً برای پشتیبانی از فضای کاربری 32 بیتی (هم برنامه ها و هم کد سیستم) توصیه می شود.
اگر پیاده سازی های دستگاه دستی شامل کمتر از 2 گیگابایت حافظه در دسترس هسته و فضای کاربر باشد، آنها:
- [7.6.1/H-1-1] باید فقط از یک ABI (فقط 64 بیتی یا فقط 32 بیتی) پشتیبانی کند.
پیاده سازی دستگاه های دستی:
- [ 7.6 .2/H-0-1] نباید یک برنامه ذخیره سازی مشترک کوچکتر از 1 گیگابایت ارائه کند.
- [ 7.7.1 /H] باید دارای یک درگاه USB باشد که از حالت جانبی پشتیبانی می کند.
اگر پیاده سازی های دستگاه دستی شامل یک پورت USB باشد که از حالت جانبی پشتیبانی می کند، آنها:
- [ 7.7 .1/H-1-1] باید API Android Open Accessory (AOA) را پیاده سازی کند.
اگر پیادهسازیهای دستگاه دستی شامل یک پورت USB باشد که از حالت میزبان پشتیبانی میکند، آنها:
- [ 7.7 .2/H-1-1] باید کلاس صوتی USB را همانطور که در مستندات Android SDK مستند شده است پیاده سازی کند.
پیاده سازی دستگاه های دستی:
- [ 7.8 .1/H-0-1] باید دارای میکروفون باشد.
- [ 7.8 .2/H-0-1] باید یک خروجی صدا داشته باشد و
android.hardware.audio.output
را اعلام کند.
اگر پیادهسازیهای دستگاه دستی قادر به برآورده کردن تمام الزامات عملکرد برای پشتیبانی از حالت VR و شامل پشتیبانی از آن باشند، آنها:
- [ 7.9 .1/H-1-1] باید پرچم ویژگی
android.hardware.vr.high_performance
را اعلام کند. - [ 7.9 .1/H-1-2] باید شامل برنامه ای باشد که
android.service.vr.VrListenerService
را اجرا می کند که می تواند توسط برنامه های VR از طریقandroid.app.Activity#setVrModeEnabled
فعال شود.
اگر پیادهسازیهای دستگاه دستی شامل یک یا چند پورت USB-C در حالت میزبان و پیادهسازی (کلاس صوتی USB)، علاوه بر الزامات بخش 7.7.2 ، آنها:
- [ 7.8 .2.2/H-1-1] باید نقشه نرم افزاری زیر را از کدهای HID ارائه کند:
تابع | نقشه برداری ها | زمینه | رفتار |
---|---|---|---|
الف | صفحه استفاده HID : 0x0C استفاده از HID : 0x0CD کلید هسته : KEY_PLAYPAUSE کلید Android : KEYCODE_MEDIA_PLAY_PAUSE | پخش رسانه | ورودی : فشار کوتاه خروجی : پخش یا مکث |
ورودی : فشار طولانی خروجی : دستور صوتی را اجرا کنید در صورتی که دستگاه قفل باشد یا صفحه نمایش آن خاموش باشد: android.speech.action.VOICE_SEARCH_HANDS_FREE را ارسال می کند . android.speech.RecognizerIntent.ACTION_WEB_SEARCH را در غیر این صورت ارسال می کند | |||
تماس ورودی | ورودی : فشار کوتاه خروجی : پذیرش تماس | ||
ورودی : فشار طولانی خروجی : رد تماس | |||
تماس در حال انجام | ورودی : فشار کوتاه خروجی : پایان تماس | ||
ورودی : فشار طولانی خروجی : بیصدا یا بیصدا کردن میکروفون | |||
ب | صفحه استفاده HID : 0x0C استفاده از HID : 0x0E9 کلید هسته : KEY_VOLUMEUP کلید Android : VOLUME_UP | پخش رسانه، تماس در حال انجام | ورودی : فشار کوتاه یا طولانی خروجی : صدای سیستم یا هدست را افزایش می دهد |
سی | صفحه استفاده HID : 0x0C استفاده از HID : 0x0EA کلید هسته : KEY_VOLUMEDOWN کلید Android : VOLUME_DOWN | پخش رسانه، تماس در حال انجام | ورودی : فشار کوتاه یا طولانی خروجی : صدای سیستم یا هدست را کاهش می دهد |
دی | صفحه استفاده HID : 0x0C استفاده از HID : 0x0CF کلید هسته : KEY_VOICECOMMAND کلید Android : KEYCODE_VOICE_ASSIST | همه در هر نمونه ای می توان راه اندازی کرد. | ورودی : فشار کوتاه یا طولانی خروجی : دستور صوتی را اجرا کنید |
- [ 7.8 .2.2/H-1-2] باید ACTION_HEADSET_PLUG را روی یک درج پلاگین راه اندازی کند، اما فقط پس از اینکه رابط های صوتی USB و نقاط پایانی به درستی شمارش شدند تا نوع ترمینال متصل شده را شناسایی کنید.
هنگامی که ترمینال صوتی USB نوع 0x0302 شناسایی شد، آنها:
- [ 7.8 .2.2/H-2-1] باید Intent ACTION_HEADSET_PLUG را با «میکروفون» اضافی روی 0 پخش کند.
هنگامی که ترمینال صوتی USB نوع 0x0402 شناسایی شد، آنها:
- [ 7.8 .2.2/H-3-1] باید Intent ACTION_HEADSET_PLUG را با «میکروفون» اضافی روی 1 پخش کند.
هنگامی که API AudioManager.getDevices () فراخوانی می شود در حالی که دستگاه جانبی USB متصل است، آنها:
[ 7.8 .2.2/H-4-1] اگر فیلد نوع پایانه صوتی USB 0x0302 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_HEADSET و نقش isSink() را فهرست کند.
[ 7.8 .2.2/H-4-2] اگر فیلد نوع پایانه صوتی USB 0x0402 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_HEADSET و نقش isSink() را فهرست کند.
[ 7.8 .2.2/H-4-3] اگر فیلد نوع پایانه صوتی USB 0x0402 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_HEADSET و نقش isSource() را فهرست کند.
[ 7.8 .2.2/H-4-4] اگر فیلد نوع پایانه صوتی USB 0x603 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_DEVICE و نقش isSink() را فهرست کند.
[ 7.8 .2.2/H-4-5] اگر فیلد نوع پایانه صوتی USB 0x604 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_DEVICE و نقش isSource() را فهرست کند.
[ 7.8 .2.2/H-4-6] اگر فیلد نوع پایانه صوتی USB 0x400 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_DEVICE و نقش isSink() را فهرست کند.
[ 7.8 .2.2/H-4-7] اگر فیلد نوع پایانه صوتی USB 0x400 باشد، باید دستگاهی از نوع AudioDeviceInfo.TYPE_USB_DEVICE و نقش isSource() را فهرست کند.
[ 7.8 .2.2/H-SR-1] برای انجام شمارش توصیفگرهای USB، شناسایی انواع ترمینال و پخش Intent ACTION_HEADSET_PLUG در کمتر از 1000 میلی ثانیه، پس از اتصال یک دستگاه صوتی USB-C به شدت توصیه می شود.
اگر پیادهسازیهای دستگاه دستی android.hardware.audio.output
و android.hardware.microphone
را اعلام کنند، آنها:
- [5.6(#56_audio-latency)/H-1-1] باید میانگین تأخیر رفت و برگشت پیوسته 800 میلی ثانیه یا کمتر در 5 اندازه گیری، با میانگین انحراف مطلق کمتر از 100 میلی ثانیه، در حداقل یک مسیر پشتیبانی شده داشته باشد.
اگر پیادهسازیهای دستگاه دستی شامل حداقل یک محرک لمسی باشد، آنها:
- [ 7.10 /H]* نباید از محرک لمسی (ویبراتور) جرم دوار غیرعادی (ERM) استفاده کرد.
- [ 7.10 /H]* باید محل قرارگیری محرک را در نزدیکی محلی قرار دهد که معمولاً دستگاه را با دست نگه داشته یا لمس میکند.
- [ 7.10 /H]* باید همه ثابتهای عمومی را برای لمسی واضح در android.view پیادهسازی کند ، تأیید، رد، GESTURE_START و GESTURE_END).
- [ 7.10 /H]* باید تمام ثابتهای عمومی برای لمسی واضح در android.os.VibrationEffect یعنی (EFFECT_TICK، EFFECT_CLICK، EFFECT_HEAVY_CLICK و EFFECT_DOUBLE_CLICK) و همه ثابتهای عمومی برای rich haptics در android.os VE_TICK ).
- [ 7.10 /H]* باید از این نگاشتهای ثابت لمسی مرتبط استفاده کرد.
- [ 7.10 /H]* باید از ارزیابی کیفیت برای
createOneShot()
وcreateWaveform()
API پیروی کرد. - [ 7.10 /H]* باید قابلیتهای مقیاسپذیری دامنه را با اجرای
android.os.Vibrator.hasAmplitudeControl()
تأیید کند.
محرک رزونانس خطی (LRA) یک سیستم فنر تک جرمی است که دارای فرکانس تشدید غالب است که در آن جرم در جهت حرکت مورد نظر ترجمه می شود.
اگر پیادهسازیهای دستگاه دستی شامل حداقل یک محرک تشدید خطی باشد، آنها:
- [ 7.10 /H]* باید محرک لمسی را در محور X جهت عمودی حرکت دهد.
اگر پیادهسازیهای دستگاه دستی دارای یک محرک لمسی باشد که محرک تشدید خطی محور X (LRA) است، آنها:
- [ 7.10 /H]* باید فرکانس تشدید LRA محور X کمتر از 200 هرتز باشد.
اگر پیاده سازی دستگاه های دستی از نگاشت ثابت های لمسی پیروی کنند، آنها:
- [7.10/H]* باید وضعیت پیاده سازی را با اجرای API های android.os.Vibrator.areAllEffectsSupported() و android.os.Vibrator.arePrimitvesSupported() تأیید کند.
- [ 7.10 /H]* باید یک ارزیابی کیفیت برای ثابت های لمسی انجام دهد.
- [7.10/H]* باید برای کاهش خطر شکست همانطور که در اینجا توضیح داده شده است، پشتیبانی مجدد ارائه دهد.
2.2.2. چند رسانه ای
پیاده سازی دستگاه های دستی باید فرمت های رمزگذاری و رمزگشایی صوتی زیر را پشتیبانی کرده و آنها را برای برنامه های شخص ثالث در دسترس قرار دهند:
- [ 5.1 /H-0-1] AMR-NB
- [ 5.1 /H-0-2] AMR-WB
- [ 5.1 /H-0-3] نمایه AAC MPEG-4 (AAC LC)
- [ 5.1 /H-0-4] نمایه MPEG-4 HE AAC (AAC+)
- [ 5.1 /H-0-5] AAC ELD (AAC تاخیر کم تقویت شده)
پیاده سازی دستگاه های دستی باید از فرمت های رمزگذاری ویدیوی زیر پشتیبانی کرده و آنها را برای برنامه های شخص ثالث در دسترس قرار دهند:
پیاده سازی دستگاه های دستی باید از فرمت های رمزگشایی ویدیوی زیر پشتیبانی کرده و آنها را برای برنامه های شخص ثالث در دسترس قرار دهند:
- [ 5.3 /H-0-1] H.264 AVC
- [ 5.3 /H-0-2] H.265 HEVC
- [ 5.3 /H-0-3] MPEG-4 SP
- [ 5.3 /H-0-4] VP8
- [ 5.3 /H-0-5] VP9
2.2.3. نرم افزار
پیاده سازی دستگاه های دستی:
- [ 3.2.3.1 /H-0-1] باید برنامهای داشته باشد که اهداف
ACTION_GET_CONTENT
،ACTION_OPEN_DOCUMENT
،ACTION_OPEN_DOCUMENT_TREE
، وACTION_CREATE_DOCUMENT
را همانطور که در اسناد SDK توضیح داده شده است، مدیریت کند و با استفاده از امکان دسترسی بهDocumentsProvider
API اطلاعات کاربر را فراهم کند. - [ 3.2.3.1 /H-0-2]* باید یک یا چند برنامه یا مؤلفه خدمات را با یک کنترل کننده هدف، برای همه الگوهای فیلتر هدف عمومی تعریف شده توسط اهداف برنامه زیر که در اینجا ذکر شده است، از قبل بارگیری کنید.
- [ 3.2.3.1 /H-SR-1] برای از پیش بارگذاری یک برنامه ایمیل که می تواند ACTION_SENDTO یا ACTION_SEND یا ACTION_SEND_MULTIPLE قصد ارسال ایمیل را مدیریت کند، اکیداً توصیه می شود.
- [ 3.4 .1/H-0-1] باید اجرای کاملی از
android.webkit.Webview
API را ارائه دهد. - [ 3.4 .2/H-0-1] باید شامل یک برنامه مرورگر مستقل برای مرور وب کاربران عمومی باشد.
- [ 3.8 .1/H-SR-1] برای اجرای یک راهانداز پیشفرض که از پین کردن میانبرها، ویجتها و ویژگیهای ویجت در برنامه پشتیبانی میکند، به شدت توصیه میشود.
- [ 3.8 .1/H-SR-2] برای پیادهسازی یک راهانداز پیشفرض که دسترسی سریع به میانبرهای اضافی ارائهشده توسط برنامههای شخص ثالث را از طریق ShortcutManager API فراهم میکند، اکیداً توصیه میشود.
- [ 3.8 .1/H-SR-3] اکیداً توصیه میشود که یک برنامه راهانداز پیشفرض که نشانها را برای نمادهای برنامه نشان میدهد، داشته باشند.
- [ 3.8 .2/H-SR-1] برای پشتیبانی از ویجت های برنامه شخص ثالث به شدت توصیه می شود.
- [ 3.8 .3/H-0-1] باید به برنامه های شخص ثالث اجازه دهد تا از طریق کلاس های
Notification
وNotificationManager
API کاربران را از رویدادهای قابل توجه مطلع کنند. - [ 3.8 .3/H-0-2] باید از اعلان های غنی پشتیبانی کند.
- [ 3.8 .3/H-0-3] باید از اعلانهای heads-up پشتیبانی کند.
- [ 3.8 .3/H-0-4] باید شامل یک سایه اعلان باشد که به کاربر امکان کنترل مستقیم (مثلاً پاسخ، به تعویق انداختن، رد کردن، مسدود کردن) اعلانها را از طریق هزینههای کاربر مانند دکمههای عمل یا پانل کنترل همانطور که اجرا میکند، میدهد. در AOSP
- [ 3.8 .3/H-0-5] باید انتخاب های ارائه شده از طریق
RemoteInput.Builder setChoices()
در سایه اعلان نمایش دهد. - [ 3.8 .3/H-SR-1] اکیداً توصیه می شود که اولین انتخاب ارائه شده از طریق
RemoteInput.Builder setChoices()
در سایه اعلان و بدون تعامل اضافی با کاربر نمایش داده شود. - [ 3.8 .3/H-SR-2] اکیداً توصیه میشود که همه گزینههای ارائه شده از طریق
RemoteInput.Builder setChoices()
در سایه اعلانها هنگامی که کاربر همه اعلانها را در سایه اعلان گسترش میدهد، نمایش داده شود. - [ 3.8 .3.1/H-SR-1] برای نمایش اقداماتی که
Notification.Action.Builder.setContextual
برای آنها به عنوانtrue
در خط با پاسخ های نمایش داده شده توسطNotification.Remoteinput.Builder.setChoices
تنظیم شده است، قویاً توصیه می شود. - [ 3.8 .4/H-SR-1] اکیداً توصیه می شود یک دستیار را روی دستگاه اجرا کنید تا عمل Assist را انجام دهد.
اگر پیادهسازیهای دستگاه دستی از عمل Assist پشتیبانی میکنند، آنها:
- [ 3.8 .4/H-SR-2] اکیداً توصیه می شود از فشار طولانی کلید
HOME
به عنوان تعامل تعیین شده برای راه اندازی برنامه کمکی همانطور که در بخش 7.2.3 توضیح داده شده است، استفاده کنید. باید برنامه کمکی انتخاب شده توسط کاربر را راهاندازی کند، به عبارت دیگر برنامهای کهVoiceInteractionService
یا فعالیتی را که هدفACTION_ASSIST
مدیریت میکند، اجرا میکند.
اگر پیادهسازیهای دستگاه دستی از conversation notifications
پشتیبانی میکنند و آنها را در بخش جداگانهای از اعلانهای هشدار و بدون مکالمه گروهبندی میکنند، آنها:
- [ 3.8 .4/H-1-1]* باید اعلانهای مکالمه را قبل از اعلانهای غیرمکالمه نمایش دهد، به استثنای اعلانهای سرویس پیشزمینه و اعلانهای اهمیت: بالا .
اگر پیادهسازیهای دستگاه Android Handheld از صفحه قفل پشتیبانی میکنند، آنها:
- [ 3.8 .10/H-1-1] باید اعلانهای صفحه قفل از جمله الگوی اعلان رسانه را نمایش دهد.
اگر پیاده سازی های دستگاه دستی از صفحه قفل ایمن پشتیبانی می کنند، آنها:
- [ 3.9 /H-1-1] باید طیف کاملی از خطمشیهای مدیریت دستگاه را که در مستندات Android SDK تعریف شده است، اجرا کند.
اگر پیادهسازیهای دستگاه دستی شامل پشتیبانی از ControlsProviderService
و Control
API باشد و به برنامههای شخص ثالث اجازه انتشار کنترلهای دستگاه را بدهد، آنها:
- [ 3.8 .16/H-1-1] باید ویژگی flag
android.software.controls
را اعلام کرده و آن را رویtrue
تنظیم کند. - [ 3.8 .16/H-1-2] باید امکان افزودن، ویرایش، انتخاب و اجرای کنترل های دستگاه مورد علاقه کاربر را از کنترل های ثبت شده توسط برنامه های شخص ثالث از طریق
ControlsProviderService
وControl
API ها فراهم کند. . - [ 3.8 0.16/H-1-3] باید دسترسی به این مقرون به صرفه کاربر را در سه تعامل از یک راهانداز پیشفرض فراهم کند.
- [ 3.8 .16/H-1-4] باید نام و نماد هر برنامه شخص ثالثی که کنترلها را از طریق
ControlsProviderService
API و همچنین فیلدهای مشخص شده توسطControl
APIها ارائه میکند، در این اطلاعات کاربر به دقت ارائه شود.
برعکس، اگر پیادهسازیهای دستگاه دستی چنین کنترلهایی را اجرا نکنند، آنها:
- [ 3.8 .16/H-2-1] باید برای
ControlsProviderService
وControl
APIهاnull
گزارش شود. - [ 3.8 .16/H-2-2] باید ویژگی flag
android.software.controls
را اعلام کرده و آن را رویfalse
تنظیم کنید.
پیاده سازی دستگاه های دستی:
- [ 3.10 /H-0-1] باید از خدمات دسترسی شخص ثالث پشتیبانی کند.
- [ 3.10 /H-SR-1] اکیداً توصیه میشود-1 برای از پیش بارگذاری سرویسهای دسترسپذیری در دستگاه قابل مقایسه با عملکرد دسترسی سوئیچ و TalkBack (برای زبانهای پشتیبانیشده توسط موتور متن به گفتار از پیش نصبشده) خدمات دسترسی بهصورت ارائه شده در پروژه منبع باز Talkback .
- [ 3.11 /H-0-1] باید از نصب موتورهای TTS شخص ثالث پشتیبانی کند.
- [ 3.11 /H-SR-1] اکیداً توصیه میشود که موتور TTS را شامل شود که از زبانهای موجود در دستگاه پشتیبانی میکند.
- [ 3.13 /H-SR-1] اکیداً توصیه میشود که شامل یک مؤلفه رابط کاربری تنظیمات سریع باشد.
اگر پیادهسازیهای دستگاه دستی Android پشتیبانی از FEATURE_BLUETOOTH
یا FEATURE_WIFI
را اعلام کنند، آنها:
- [ 3.16 /H-1-1] باید از ویژگی جفت شدن دستگاه همراه پشتیبانی کند.
اگر عملکرد پیمایش بهعنوان یک عمل مبتنی بر اشاره روی صفحه ارائه شود:
- [ 7.2 .3/H] منطقه تشخیص حرکت برای عملکرد Home نباید از پایین صفحه در ارتفاع بالاتر از 32 dp باشد.
اگر پیاده سازی های دستگاه دستی یک عملکرد ناوبری را به عنوان یک حرکت از هر نقطه در لبه های چپ و راست صفحه ارائه می دهند:
- [ 7.2 .3/H-0-1] ناحیه اشاره عملکرد ناوبری باید کمتر از 40 dp در عرض در هر طرف باشد. پهنای ژست باید به طور پیش فرض 24 dp باشد.
اگر پیادهسازیهای دستگاه دستی از یک صفحه قفل امن پشتیبانی میکنند و بیش از یا مساوی 2 گیگابایت حافظه در اختیار هسته و فضای کاربر دارند، آنها:
- [3.9/H-1-2] باید پشتیبانی از نمایه های مدیریت شده را از طریق پرچم ویژگی
android.software.managed_users
اعلام کند.
اگر پیادهسازیهای دستگاه دستی اندروید پشتیبانی از دوربین را از طریق android.hardware.camera.any
اعلام کنند، آنها:
- [ 7.5 .4/H-1-1] باید به قصد
android.media.action.STILL_IMAGE_CAMERA
وandroid.media.action.STILL_IMAGE_CAMERA_SECURE
احترام بگذارد و دوربین را در حالت تصویر ثابت همانطور که در SDK توضیح داده شده راه اندازی کند. - [ 7.5 .4/H-1-2] باید به قصد
android.media.action.VIDEO_CAMERA
برای راهاندازی دوربین در حالت ویدئو همانطور که در SDK توضیح داده شده است، احترام بگذارد.
2.2.4. عملکرد و قدرت
- [ 8.1 /H-0-1] تأخیر فریم ثابت . تأخیر ناسازگار فریم یا تأخیر در ارائه فریمها نباید بیشتر از 5 فریم در ثانیه اتفاق بیفتد و باید کمتر از 1 فریم در ثانیه باشد.
- [ 8.1 /H-0-2] تأخیر رابط کاربری . پیادهسازیهای دستگاه باید با پیمایش فهرستی از 10 هزار ورودی فهرست که توسط مجموعه تست سازگاری Android (CTS) در کمتر از 36 ثانیه تعریف شده است، تجربه کاربر با تأخیر کم را تضمین کنند.
- [ 8.1 /H-0-3] تعویض وظیفه . هنگامی که چندین برنامه راه اندازی شده اند، راه اندازی مجدد یک برنامه از قبل در حال اجرا پس از راه اندازی باید کمتر از 1 ثانیه طول بکشد.
پیاده سازی دستگاه های دستی:
- [ 8.2 /H-0-1] باید عملکرد نوشتن متوالی حداقل 5 مگابایت بر ثانیه را تضمین کند.
- [ 8.2 /H-0-2] باید از عملکرد نوشتن تصادفی حداقل 0.5 مگابایت بر ثانیه اطمینان حاصل کند.
- [ 8.2 /H-0-3] باید عملکرد خواندن متوالی حداقل 15 مگابایت بر ثانیه را تضمین کند.
- [ 8.2 /H-0-4] باید عملکرد خواندن تصادفی حداقل 3.5 مگابایت بر ثانیه را تضمین کند.
اگر پیادهسازیهای دستگاه دستی شامل ویژگیهایی برای بهبود مدیریت انرژی دستگاه باشد که در AOSP گنجانده شده است یا ویژگیهای موجود در AOSP را گسترش دهد، آنها:
- [ 8.3 /H-1-1] باید توانایی کاربر را برای فعال و غیرفعال کردن ویژگی صرفه جویی باتری فراهم کند.
- [ 8.3 /H-1-2] باید برای نمایش همه برنامههایی که از حالتهای ذخیره انرژی برنامه و Doze معاف هستند، امکانات لازم را برای کاربر فراهم کند.
پیاده سازی دستگاه های دستی:
- [ 8.4 /H-0-1] باید یک نمایه قدرت برای هر جزء ارائه کند که مقدار مصرف فعلی را برای هر جزء سخت افزاری و تخلیه تقریبی باتری ناشی از قطعات در طول زمان، همانطور که در سایت پروژه منبع باز Android مستند شده است، تعریف کند.
- [ 8.4 /H-0-2] باید تمام مقادیر مصرف برق را بر حسب میلی آمپر ساعت (mAh) گزارش کند.
- [ 8.4 /H-0-3] باید مصرف انرژی CPU را در هر UID فرآیند گزارش کند. پروژه منبع باز Android از طریق اجرای ماژول هسته
uid_cputime
این نیاز را برآورده می کند. - [ 8.4 /H-0-4] باید این مصرف انرژی را از طریق دستور
adb shell dumpsys batterystats
shell در اختیار توسعهدهنده برنامه قرار دهد. - [ 8.4 /H] باید به خود مؤلفه سخت افزار نسبت داده شود اگر نمی توان مصرف برق جزء سخت افزاری را به یک برنامه نسبت داد.
اگر پیاده سازی های دستگاه دستی شامل یک صفحه نمایش یا خروجی ویدیو باشد، آنها:
- [ 8.4 /H-1-1] باید از
android.intent.action.POWER_USAGE_SUMMARY
هدف خودداری کنید و یک منوی تنظیمات را نمایش دهید که این استفاده از قدرت را نشان می دهد.
2.2.5. مدل امنیتی
پیاده سازی دستگاه های دستی:
- [ 9.1 /H-0-1] باید به برنامه های شخص ثالث اجازه دهد تا از طریق
android.permission.PACKAGE_USAGE_STATS
به آمار استفاده دسترسی پیدا کنند و یک مکانیزم قابل دسترسی کاربر را برای اعطای یا لغو دسترسی به چنین برنامه هایی در پاسخ بهandroid.settings.ACTION_USAGE_ACCESS_SETTINGS
فراهم کنند.android.settings.ACTION_USAGE_ACCESS_SETTINGS
قصد.
پیاده سازی دستگاه های دستی:
- [ 9.11 /H-0-2] باید از اجرای کلیدی با یک محیط اجرای جدا شده پشتیبان تهیه کنید.
- [ 9.11 /H-0-3] باید الگوریتم های رمزنگاری RSA ، AES ، ECDSA و HMAC و عملکردهای هش Family MD5 ، Sha1 و Sha-2 را برای پشتیبانی صحیح از الگوریتم های پشتیبانی شده سیستم کلیدی اندرویدی در منطقه ای که به طور ایمن پشتیبانی می کند ، داشته باشد. جدا شده از کد در حال اجرا بر روی هسته و بالاتر. جداسازی ایمن باید تمام مکانیسم های بالقوه را که توسط آن هسته یا کد فضای کاربری ممکن است به وضعیت داخلی محیط جدا شده ، از جمله DMA دسترسی داشته باشد ، مسدود کند. پروژه منبع باز اندرویدی بالادست (AOSP) با استفاده از اجرای قابل اعتماد ، این نیاز را برآورده می کند ، اما یک راه حل مبتنی بر ARM TrustZone یا یک شخص ثالث اجرای ایمن یک جداسازی مناسب مبتنی بر Hypervisor گزینه های جایگزین است.
- [ 9.11 /H-0-4] باید احراز هویت صفحه قفل را در محیط اجرای جدا شده انجام داده و فقط در صورت موفقیت ، از کلیدهای محدود به تأیید اعتبار استفاده کنید. اعتبارنامه صفحه قفل باید به گونه ای ذخیره شود که فقط به محیط اجرای جدا شده اجازه می دهد تا احراز هویت صفحه قفل را انجام دهد. پروژه منبع باز اندرویدی بالادست ، لایه انتزاع سخت افزار Gatekeeper (HAL) و قابل اعتماد را فراهم می کند که می تواند برای برآورده کردن این نیاز استفاده شود.
- [ 9.11 /H-0-5] باید از تأیید کلید پشتیبانی کند که کلید امضاء تأیید شده توسط سخت افزار ایمن محافظت می شود و امضای آن در سخت افزار ایمن انجام می شود. کلیدهای امضای تأیید باید در تعداد کافی از دستگاه ها به اشتراک گذاشته شوند تا از استفاده کلیدها به عنوان شناسه دستگاه جلوگیری شود. یکی از راه های تأمین این شرط ، به اشتراک گذاشتن همان کلید تأیید است ، مگر اینکه حداقل 100000 واحد از یک SKU معین تولید شود. اگر بیش از 100000 واحد SKU تولید شود ، ممکن است برای هر 100000 واحد از یک کلید متفاوت استفاده شود.
- [9/H-0-1] باید ویژگی "android.hardware.security.model.compative" را اعلام کند.
توجه داشته باشید که اگر اجرای دستگاه در حال حاضر بر روی نسخه قبلی Android راه اندازی شده باشد ، چنین دستگاهی از الزام داشتن یک کلیدی پشتیبانی شده توسط یک محیط اجرای جدا شده معاف است و از تأیید کلید پشتیبانی می کند ، مگر اینکه ویژگی android.hardware.fingerprint
را اعلام کند که کدام یک از ویژگی های Android. نیاز به یک کلبه کلیدی دارد که توسط یک محیط اعدام منزوی پشتیبانی می شود.
هنگامی که پیاده سازی دستگاه های دستی از صفحه قفل ایمن پشتیبانی می کند ، آنها:
- [ 9.11 /H-1-1] باید به کاربر اجازه دهد کوتاهترین زمان خواب را انتخاب کند ، یعنی زمان انتقال از قفل به حالت قفل شده ، به عنوان 15 ثانیه یا کمتر.
- [ 9.11 /H-1-2] باید برای مخفی کردن اعلان ها و غیرفعال کردن کلیه اشکال تأیید اعتبار ، به جز احراز هویت اصلی که در صفحه قفل امن 9.11.1 شرح داده شده است ، هزینه کاربر را فراهم کند. AOSP با نیاز به عنوان حالت قفل مطابقت دارد.
اگر پیاده سازی دستگاه های دستی شامل چندین کاربر باشد و پرچم ویژگی android.hardware.telephony
را اعلام نکنید ، آنها:
- [ 9.5 /H-2-1] باید از پروفایل های محدود پشتیبانی کند ، ویژگی ای که به صاحبان دستگاه اجازه می دهد کاربران اضافی و قابلیت های آنها را در دستگاه مدیریت کنند. با پروفایل های محدود ، صاحبان دستگاه می توانند به سرعت محیط های جداگانه ای را برای کاربران اضافی تنظیم کنند ، با این امکان که بتوانند محدودیت های ریز ریز در برنامه هایی را که در آن محیط ها موجود است ، مدیریت کنند.
اگر پیاده سازی دستگاه های دستی شامل چندین کاربر باشد و پرچم ویژگی android.hardware.telephony
را اعلام کنید ، آنها:
- [ 9.5 /H-3-1] نباید از پروفایل های محدود پشتیبانی کند بلکه باید با اجرای AOSP کنترل ها هماهنگ باشد تا سایر کاربران را از دسترسی به تماس های صوتی و پیام کوتاه فعال یا غیرفعال کند.
Android ، از طریق سیستم API VoiceInteractionService از مکانیسمی برای تشخیص ایمن همیشه در مورد Hot-Word بدون نشانه دسترسی MIC پشتیبانی می کند
اگر پیاده سازی دستگاه های دستی از سیستم API HotwordDetectionService
یا مکانیسم دیگری برای تشخیص هات کلمه بدون نشانه دسترسی به MIC پشتیبانی کند ، آنها:
- [9.8/H-1-1] باید اطمینان حاصل کنید که سرویس تشخیص کلمه Hot-Word فقط می تواند داده ها را به سیستم یا ContentCaptureservice منتقل کند
- [9.8/H-1-2] باید اطمینان حاصل کنید که سرویس تشخیص کلمه Hot-Word فقط می تواند داده های صوتی MIC یا داده های حاصل از آن را از طریق API
HotwordDetectionService
به سرور سیستم منتقل کند ، یا از طریق ContentCaptureManager APIContentCaptureManager
را بهContentCaptureService
منتقل کند. - [9.8/H-1-3] نباید صوتی MIC را که بیش از 30 ثانیه برای درخواست شخصی برای تغییر سخت افزار به سرویس تشخیص کلمه Hotword است ، عرضه کند.
- [9.8/H-1-4] برای درخواست فردی به سرویس تشخیص Word Hot-Word نباید MIC بافر قدیمی تر از 8 ثانیه را تأمین کند.
- [9.8/H-1-5] نباید MIC بافر را از 30 ثانیه مسن تر از 30 ثانیه به سرویس تعامل صوتی یا نهاد مشابه عرضه کند.
- [9.8/H-1-6] نباید اجازه دهد بیش از 100 بایت داده از سرویس تشخیص کلمه Hot-Word در هر نتیجه موفق کلمه HOTWORD منتقل شود.
- [9.8/H-1-7] نباید اجازه دهد بیش از 5 بیت داده از سرویس تشخیص کلمه هات در هر نتیجه منفی کلمه منفی منتقل شود.
- [9.8/H-1-8] فقط باید انتقال داده ها را از سرویس تشخیص HotWord در درخواست اعتبار سنجی HotWord از سرور سیستم فراهم کند.
- [9.8/H-1-9] نباید به یک برنامه قابل نصب کاربر اجازه دهد تا سرویس تشخیص کلمه HotWord را ارائه دهد.
- [9.8/H-1-10] نباید در داده های کمی در مورد استفاده از میکروفون توسط سرویس تشخیص کلمه Hot-Word ، سطح داده شود.
- [9.8/H-1-11] باید تعداد بایت های موجود در هر انتقال را از سرویس تشخیص HotWord وارد کند تا امکان بازرسی برای محققان امنیتی فراهم شود.
- [9.8/H-1-12] باید از یک حالت اشکال زدایی پشتیبانی کند که محتویات خام هر انتقال را از سرویس تشخیص کلمه هات وارد کند تا امکان بازرسی برای محققان امنیتی را فراهم کند.
- [9.8/H-1-13] باید حداقل یک بار در هر ساعت یا هر 30 رویداد سخت افزاری را که هر کدام از اول باشد ، مراحل میزبانی سرویس تشخیص Hot-Word را مجدداً راه اندازی کنید.
- [9.8/H-1-14] باید همانطور که در بخش 9.8.2 توضیح داده شده است ، هنگامی که یک نتیجه کلمه کلمه ای موفق به سرویس تعامل صوتی یا نهاد مشابه منتقل می شود ، نشانگر میکروفون را نشان دهد.
- [9.8/H-SR-1] به شدت توصیه می شود قبل از تنظیم برنامه به عنوان ارائه دهنده سرویس تشخیص HotWord ، به کاربران اطلاع دهید.
- [9.8/H-SR-2] به شدت توصیه می شود که از انتقال داده های بدون ساختار خارج از سرویس تشخیص کلمه Hot-Word استفاده کنید.
اگر پیاده سازی دستگاه شامل برنامه ای است که از سیستم API HotwordDetectionService
یا مکانیسم مشابه برای تشخیص هات کلمه بدون نشانه استفاده از MIC استفاده می کند ، برنامه:
- [9.8/H-2-1] باید برای هر عبارت hotword پشتیبانی شده ، اخطار صریح را به کاربر ارائه دهد.
- [9.8/H-2-2] نباید داده های صوتی خام یا داده های حاصل از آن را از طریق سرویس تشخیص کلمه Hot-Word حفظ کند.
- [9.8/H-2-3] نباید از سرویس تشخیص Word Word ، داده های صوتی ، داده هایی که می توان برای بازسازی (کاملاً یا جزئی) استفاده کرد ، یا محتوای صوتی غیر مرتبط با خود Hot-Word ، به جز
ContentCaptureService
، منتقل شود.
اگر پیاده سازی دستگاه های دستی android.hardware.microphone
اعلام کنید ، آنها:
- [ 9.8.2 /h-4-1] باید هنگام دسترسی به داده های صوتی از میکروفون ، نشانگر میکروفون را نمایش دهد ، اما نه وقتی میکروفون فقط توسط
HotwordDetectionService
،SOURCE_HOTWORD
،ContentCaptureService
یا برنامه هایی که نقش های نامیده شده در بخش را دارند ، قابل دسترسی است. 9.1 با شناسه CDD [C-4-X]. . - [ 9.8.2 /H-4-2] باید لیست برنامه های اخیر و فعال را با استفاده از میکروفون به عنوان بازگشت از
PermissionManager.getIndicatorAppOpUsageData()
به همراه هر پیام انتساب مرتبط با آنها نمایش دهد. - [ 9.8.2 /H-4-3] نباید نشانگر میکروفون را برای برنامه های سیستم که دارای رابط های کاربر قابل مشاهده یا تعامل کاربر هستند ، پنهان کند.
- [ 9.8.2 /H-4-4] باید لیست برنامه های اخیر و فعال را با استفاده از میکروفون به عنوان بازگشت از
PermissionManager.getIndicatorAppOpUsageData()
به همراه هر پیام انتساب مرتبط با آنها نمایش دهد.
اگر پیاده سازی دستگاه های دستی android.hardware.camera.any
را اعلام کنید ، آنها:
- [ 9.8.2 /H-5-1] باید هنگام دسترسی به داده های دوربین زنده ، نشانگر دوربین را نمایش دهد ، اما نه وقتی دوربین فقط توسط برنامه (ها) که نقش های نامیده شده در بخش 9.1 را با شناسه CDD به دست می آورد ، دسترسی پیدا می کند. [C-4-X].
- [ 9.8.2 /H-5-2] باید برنامه های اخیر و فعال را با استفاده از دوربین به عنوان بازگشت از
PermissionManager.getIndicatorAppOpUsageData()
، به همراه هر پیام انتساب مرتبط با آنها نمایش دهد. - [ 9.8.2 /H-5-3] نباید نشانگر دوربین را برای برنامه های سیستم که دارای رابط های کاربر قابل مشاهده یا تعامل مستقیم کاربر هستند ، پنهان کند.
2.2.6. ابزارهای توسعه دهنده و سازگاری گزینه ها
پیاده سازی دستگاه های دستی (* برای رایانه لوحی قابل اجرا نیست):
- [ 6.1 /H-0-1]* باید از فرمان پوسته
cmd testharness
پشتیبانی کند.
پیاده سازی دستگاه های دستی (* برای رایانه لوحی قابل اجرا نیست):
- پرفراتو
- [ 6.1 /H-0-2]* باید باینری A
/system/bin/perfetto
را در معرض کاربر پوسته قرار دهید که Cmdline با مستندات Perfetto مطابقت دارد. - [ 6.1 /H-0-3]* باینری Perfetto باید به عنوان ورودی یک پیکربندی ProtoBUF که مطابق با طرحواره تعریف شده در مستندات Perfetto است ، بپذیرد.
- [ 6.1 /H-0-4]* باینری Perfetto باید به عنوان خروجی یک ردیابی Protobuf بنویسد که مطابق با طرحواره تعریف شده در مستندات Perfetto است .
- [ 6.1 /H-0-5]* باید حداقل از طریق باینری Perfetto ، حداقل منابع داده شرح داده شده در مستندات Perfetto را فراهم کند.
- [ 6.1 /H-0-6]* Daemon Treced Perfetto باید به طور پیش فرض فعال شود (خاصیت سیستم
persist.traced.enable
).
- [ 6.1 /H-0-2]* باید باینری A
2.2.7. کلاس عملکرد رسانه ای دستی
برای تعریف کلاس عملکرد رسانه به بخش 7.11 مراجعه کنید.
2.2.7.1. رسانه ها
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.R
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- باید نیازهای رسانه ای ذکر شده در Android 11 CDD بخش 2.2.7.1 را برآورده کند
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.S
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- [5.1/H-1-1] باید حداکثر تعداد جلسات رمزگشایی ویدیویی سخت افزاری را که می تواند همزمان در هر ترکیب کدک از طریق
CodecCapabilities.getMaxSupportedInstances()
انجام شودVideoCapabilities.getSupportedPerformancePoints()
تبلیغ کنید. - [5.1/H-1-2] باید از 6 نمونه از جلسات رمزگشایی ویدیویی سخت افزاری (AVC ، HEVC ، VP9* یا بالاتر) در هر ترکیب کدک که همزمان با وضوح 720p@30 فریم در ثانیه اجرا می شود ، پشتیبانی کند. *در صورت وجود کدک VP9 فقط 2 نمونه لازم است.
- [5.1/H-1-3] باید حداکثر تعداد جلسات رمزگذار ویدیویی سخت افزاری را که می تواند همزمان در هر ترکیب کدک از طریق
CodecCapabilities.getMaxSupportedInstances()
انجام شودVideoCapabilities.getSupportedPerformancePoints()
تبلیغ کنید. - [5.1/H-1-4] باید از 6 نمونه از جلسات رمزگذار ویدیویی سخت افزاری (AVC ، HEVC ، VP9* یا بعد) در هر ترکیب کدک که همزمان با وضوح 720p@30fps اجرا می شود ، پشتیبانی کند. *در صورت وجود کدک VP9 فقط 2 نمونه لازم است.
- [5.1/H-1-5] باید حداکثر تعداد رمزگذار ویدیوی سخت افزاری و جلسات رمزگشایی را که می تواند همزمان در هر ترکیب کدک از طریق
CodecCapabilities.getMaxSupportedInstances()
انجام شودVideoCapabilities.getSupportedPerformancePoints()
تبلیغ کنید. - [5.1/H-1-6] باید از 6 نمونه از رمزگذار ویدیوی سخت افزاری و جلسات رمزگذار ویدیویی سخت افزاری (AVC ، HEVC ، VP9* یا بعد) در هر ترکیب کدک که به طور همزمان در وضوح 720p@30fps اجرا می شود ، پشتیبانی کند. *در صورت وجود کدک VP9 فقط 2 نمونه لازم است.
- [5.1/H-1-7] باید در یک جلسه رمزگذاری ویدیویی 1080p یا کوچکتر برای همه رمزگذارهای ویدیویی سخت افزاری (غیر از کدک Dolby Vision) در زمان بارگذاری ، یک تأخیر اولیه کدک داشته باشد. بار در اینجا به عنوان یک جلسه رمزگذاری ویدیویی فقط 1080p تا 720p با استفاده از کدک های ویدیویی سخت افزاری به همراه اولیه ضبط ضبط صوتی 1080p تعریف شده است.
- [5.1/H-1-8] باید برای یک جلسه رمزگذاری صوتی 128 کیلوبیت در ثانیه یا کمتر از جلسه رمزگذاری صوتی BITRATE برای همه رمزگذارهای صوتی در هنگام بار ، یک تأخیر اولیه کدک داشته باشد. بار در اینجا به عنوان یک جلسه رمزگذاری ویدیویی فقط 1080p تا 720p با استفاده از کدک های ویدیویی سخت افزاری به همراه اولیه ضبط ضبط صوتی 1080p تعریف شده است.
- [5.3/H-1-1] برای یک جلسه ویدیویی 1080p 60 FPS تحت بار نباید بیش از 2 فریم را در 10 ثانیه (یعنی کمتر از 0.333 درصد افت فریم) کاهش دهد. بار به عنوان یک جلسه رمزگذاری ویدیویی فقط 1080p تا 720p با استفاده از کدک های ویدیویی سخت افزاری و همچنین پخش صوتی AAC 128 Kbps تعریف می شود.
- [5.3/H-1-2] نباید در طی 10 ثانیه بیش از 2 فریم در طی یک وضوح تصویری در یک جلسه ویدیویی 60 فریم در ثانیه تحت بار کاهش یابد. بار به عنوان یک جلسه رمزگذاری ویدیویی فقط 1080p تا 720p با استفاده از کدک های ویدیویی سخت افزاری و همچنین پخش صوتی AAC 128 Kbps تعریف می شود.
- [5.6/H-1-1] باید با استفاده از تست TAP-TONE OBOETESTER یا تست تأیید کننده CTS TONE ، یک تاخیر شیر به رنگ کمتر از 100 میلی ثانیه داشته باشد.
2.2.7.2. دوربین
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.R
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- باید نیازهای دوربین ذکر شده در Android 11 CDD بخش 2.2.7.2 را برآورده کند
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.S
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- [7.5/H-1-1] باید یک دوربین عقب اصلی با وضوح حداقل 12 مگاپیکسلی که از ضبط فیلم در 4K@30fps پشتیبانی می کند ، داشته باشد. دوربین اصلی عقب دوربین عقب با کمترین شناسه دوربین است.
- [7.5/H-1-2] باید یک دوربین جلوی اصلی با وضوح حداقل 5 مگاپیکسلی داشته و از ضبط فیلمبرداری در 1080p@30fps پشتیبانی کند. دوربین جلوی اصلی دوربین جلویی با کمترین شناسه دوربین است.
- [7.5/H-1-3] باید از ویژگی های
android.info.supportedHardwareLevel
به عنوانFULL
یا بهتر برای پشتی اولیه وLIMITED
یا بهتر برای دوربین اصلی جلو پشتیبانی کند. - [7.5/H-1-4] باید از
CameraMetadata.SENSOR_INFO_TIMESTAMP_SOURCE_REALTIME
برای هر دو دوربین اصلی پشتیبانی کند. - [7.5/H-1-5] باید Camera2 JPEG Capture Latency <1000 ms را برای وضوح 1080p داشته باشد ، همانطور که توسط دوربین CTS در شرایط روشنایی (3000K) برای هر دو دوربین اصلی اندازه گیری می شود.
- [7.5/H-1-6] باید دارای تاخیر راه اندازی Camera2 (دوربین باز برای اولین قاب پیش نمایش) <600 ms باشد که توسط CTS Camera Performancetest تحت شرایط روشنایی (3000K) برای هر دو دوربین اصلی اندازه گیری می شود.
- [7.5/H-1-8] باید از
CameraMetadata.REQUEST_AVAILABLE_CAPABILITIES_RAW
وandroid.graphics.ImageFormat.RAW_SENSOR
برای دوربین اصلی پشت پشتیبانی کند.
2.2.7.3. سخت افزار
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.R
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- باید نیازهای سخت افزاری ذکر شده در Android 11 CDD بخش 2.2.7.3 را برآورده کند
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.S
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- [7.1.1.1/H-2-1] باید وضوح صفحه حداقل 1080p داشته باشد.
- [7.1.1.3/H-2-1] باید چگالی صفحه حداقل 400 dpi داشته باشد.
- [7.6.1/H-2-1] باید حداقل 6 گیگابایت حافظه فیزیکی داشته باشد.
2.2.7.4. عملکرد
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.R
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- باید نیازهای عملکرد ذکر شده در Android 11 CDD بخش 2.2.7.4 را برآورده کند
اگر پیاده سازی دستگاه های دستی android.os.Build.VERSION_CODES.S
را برای android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
برگردانید ، پس آنها:
- [8.2/H-2-1] باید عملکرد نوشتن متوالی حداقل 125 مگابایت در ثانیه را تضمین کند.
- [8.2/H-2-2] باید عملکرد نوشتن تصادفی حداقل 10 مگابایت در ثانیه را تضمین کند.
- [8.2/H-2-3] باید عملکرد خواندن متوالی حداقل 250 مگابایت در ثانیه را تضمین کند.
- [8.2/H-2-4] باید عملکرد خواندن تصادفی حداقل 40 مگابایت در ثانیه را تضمین کند.
2.3. الزامات تلویزیونی
یک دستگاه تلویزیونی Android به اجرای دستگاه Android اشاره دارد که یک رابط سرگرمی برای مصرف رسانه های دیجیتال ، فیلم ها ، بازی ها ، برنامه ها و/یا تلویزیون زنده برای کاربرانی است که در حدود ده فوت دورتر نشسته اند (یک کاربر "لاغر" یا "کاربر 10 پا رابط ").
در صورت رعایت همه معیارهای زیر ، پیاده سازی دستگاه های Android به عنوان یک تلویزیون طبقه بندی می شوند:
- مکانیسمی را برای کنترل از راه دور رابط کاربری ارائه شده بر روی صفحه نمایش فراهم کرده اند که ممکن است ده پا از کاربر دور باشد.
- یک صفحه نمایش صفحه نمایش تعبیه شده با طول مورب بزرگتر از 24 اینچ داشته باشید یا شامل یک درگاه خروجی ویدیویی مانند VGA ، HDMI ، DisplayPort یا یک درگاه بی سیم برای صفحه نمایش باشید.
الزامات اضافی در بقیه این بخش مخصوص پیاده سازی دستگاه های تلویزیون اندرویدی است.
2.3.1. سخت افزار
پیاده سازی دستگاه های تلویزیونی:
- [ 7.2 .2/T-0-1] باید از D-Pad پشتیبانی کند.
- [ 7.2 .3/T-0-1] باید توابع خانه و پشت را ارائه دهد.
- [ 7.2 .3/t-0-2] باید هر دو رویداد فشار عادی و طولانی عملکرد پشتی (
KEYCODE_BACK
) را به برنامه پیش زمینه ارسال کنید. - [ 7.2 .6.1/T-0-1] باید پشتیبانی از کنترل کننده های بازی را شامل شود و پرچم ویژگی
android.hardware.gamepad
را اعلام کنید. - [ 7.2 .7/t] باید یک کنترل از راه دور را فراهم کند که کاربران بتوانند به ورودی های کلیدهای ناوبری غیر لمسی و کلیدهای ناوبری دسترسی پیدا کنند.
اگر پیاده سازی دستگاه های تلویزیونی شامل ژیروسکوپ 3 محوره باشد ، آنها:
- [ 7.3 .4/t-1-1] باید بتواند رویدادها را تا فرکانس حداقل 100 هرتز گزارش دهد.
- [ 7.3 .4/t-1-2] باید قادر به اندازه گیری تغییرات جهت گیری تا 1000 درجه در ثانیه باشد.
پیاده سازی دستگاه های تلویزیونی:
- [ 7.4 .3/T-0-1] باید از بلوتوث و بلوتوث LE پشتیبانی کند.
- [ 7.6 .1/T-0-1] باید حداقل 4 گیگابایت ذخیره غیر فرار برای برنامه های خصوصی برنامه (با نام "/داده" پارتیشن) داشته باشد.
اگر پیاده سازی دستگاه های تلویزیونی شامل یک درگاه USB است که از حالت میزبان پشتیبانی می کند ، آنها:
- [ 7.5 .3/t-1-1] باید شامل پشتیبانی از یک دوربین خارجی باشد که از طریق این درگاه USB متصل می شود اما لزوماً همیشه به هم وصل نمی شود.
اگر پیاده سازی دستگاه های تلویزیونی 32 بیتی باشد:
[ 7.6 .1/t-1-1] حافظه موجود در هسته و فضای کاربری باید حداقل 896 مگابایت باشد در صورت استفاده از چگالی های زیر:
- 400DPI یا بالاتر در صفحه های کوچک/عادی
- XHDPI یا بالاتر در صفحه های بزرگ
- TVDPI یا بالاتر در صفحه های فوق العاده بزرگ
اگر پیاده سازی دستگاه های تلویزیونی 64 بیتی باشد:
[ 7.6 .1/T-2-1] حافظه موجود در هسته و فضای کاربری باید حداقل در صورت استفاده از چگالی زیر 1280 مگابایت باشد:
- 400DPI یا بالاتر در صفحه های کوچک/عادی
- XHDPI یا بالاتر در صفحه های بزرگ
- TVDPI یا بالاتر در صفحه های فوق العاده بزرگ
توجه داشته باشید که "حافظه در دسترس برای هسته و فضای کاربری" در بالا به فضای حافظه ارائه شده علاوه بر هر حافظه ای که قبلاً به اجزای سخت افزاری مانند رادیو ، فیلم و موارد دیگر اختصاص داده شده است ، اشاره دارد.
پیاده سازی دستگاه های تلویزیونی:
- [ 7.8 .1/t] باید شامل میکروفون باشد.
- [ 7.8 .2/t-0-1] باید یک خروجی صوتی داشته باشد و
android.hardware.audio.output
را اعلام کند.
2.3.2. چند رسانه ای
اجرای دستگاه های تلویزیونی باید از قالب های رمزگذاری و رمزگشایی صوتی زیر پشتیبانی کند و آنها را در دسترس برنامه های شخص ثالث قرار دهد:
- [ 5.1 /T-0-1] پروفایل MPEG-4 AAC (AAC LC)
- [ 5.1 /T-0-2] مشخصات MPEG-4 HE AAC (AAC+)
- [ 5.1 /T-0-3] AAC ELD (افزایش تأخیر کم AAC)
پیاده سازی دستگاه های تلویزیونی باید از قالب های رمزگذاری ویدیویی زیر پشتیبانی کند و آنها را در دسترس برنامه های شخص ثالث قرار دهد:
پیاده سازی دستگاه های تلویزیونی:
- [ 5.2 .2/T-SR-1] به شدت توصیه می شود که از رمزگذاری H.264 فیلم های وضوح 720p و 1080p در 30 فریم در ثانیه پشتیبانی کنید.
پیاده سازی دستگاه های تلویزیونی باید از قالب های رمزگشایی ویدیویی زیر پشتیبانی کند و آنها را در دسترس برنامه های شخص ثالث قرار دهد:
- [ 5.3.3 /T-0-1] MPEG-4 SP
- [ 5.3.4 /T-0-2] H.264 AVC
- [ 5.3.5 /t-0-3] H.265 HEVC
- [ 5.3.6 /T-0-4] VP8
- [ 5.3.7 /T-0-5] VP9
- [ 5.3.1 /T-0-6] MPEG-2
پیاده سازی دستگاه های تلویزیونی باید از رمزگشایی MPEG-2 پشتیبانی کند ، همانطور که در بخش 5.3.1 به تفصیل در نرخ و قطعنامه های استاندارد فریم و ویدیویی تا و از جمله:
- [ 5.3.1 /t-1-1] HD 1080p در 29.97 فریم در ثانیه با سطح بالایی مشخصات اصلی.
- [ 5.3.1 /T-1-2] HD 1080I در 59.94 فریم در ثانیه با سطح بالایی مشخصات اصلی. آنها باید ویدیوی MPEG-2 را به هم متصل کنند و آن را در دسترس برنامه های شخص ثالث قرار دهند.
پیاده سازی دستگاه های تلویزیونی باید از رمزگشایی H.264 پشتیبانی کند ، همانطور که در بخش 5.3.4 به تفصیل در نرخ و وضوح وضوح ویدیویی استاندارد تا و از جمله:
- [ 5.3.4 /t-1-1] HD 1080p در 60 فریم در ثانیه با مشخصات پایه
- [ 5.3.4 /t-1-2] HD 1080p در 60 فریم در ثانیه با مشخصات اصلی
- [ 5.3.4 /t-1-3] HD 1080p در 60 فریم در ثانیه با سطح بالاترین سطح 4.2
پیاده سازی دستگاه های تلویزیونی با رمزگشاهای سخت افزاری H.265 باید از رمزگشایی H.265 پشتیبانی کند ، همانطور که در بخش 5.3.5 به تفصیل در نرخ و وضوح ویدیویی استاندارد تا و از جمله:
- [ 5.3.5 /t-1-1] HD 1080p در 60 فریم در ثانیه با سطح مشخصات اصلی 4.1
اگر پیاده سازی دستگاه های تلویزیونی با رمزگشاهای سخت افزاری H.265 از رمزگشایی H.265 و مشخصات رمزگشایی UHD پشتیبانی می کند ، آنها:
- [ 5.3.5 /t-2-1] باید از مشخصات رمزگشایی UHD در 60 فریم در ثانیه با مشخصات اصلی سطح 5 Main10 پشتیبانی کند
پیاده سازی دستگاه های تلویزیونی باید از رمزگشایی VP8 پشتیبانی کند ، همانطور که در بخش 5.3.6 به تفصیل در نرخ و وضوح ویدیویی استاندارد تا و از جمله موارد زیر آمده است:
- [ 5.3.6 /t-1-1] HD 1080p در 60 فریم در مشخصات رمزگشایی دوم
پیاده سازی دستگاه های تلویزیونی با رمزگشاهای سخت افزاری VP9 باید از رمزگشایی VP9 پشتیبانی کند ، همانطور که در بخش 5.3.7 به تفصیل در نرخ و وضوح استاندارد فریم و ویدیویی تا و از جمله:
- [ 5.3.7 /t-1-1] HD 1080p در 60 فریم در ثانیه با مشخصات 0 (عمق رنگ 8 بیتی)
اگر پیاده سازی دستگاه های تلویزیونی با رمزگشاهای سخت افزار VP9 از رمزگشایی VP9 و مشخصات رمزگشایی UHD پشتیبانی می کند ، آنها:
- [ 5.3.7 /T-2-1] باید از مشخصات رمزگشایی UHD در 60 فریم در ثانیه با مشخصات 0 (عمق رنگ 8 بیتی) پشتیبانی کند.
- [ 5.3.7 /T-2-1] به شدت توصیه می شود تا از مشخصات رمزگشایی UHD در 60 فریم در ثانیه با مشخصات 2 (عمق رنگ 10 بیتی) پشتیبانی کنید.
پیاده سازی دستگاه های تلویزیونی:
- [ 5.5 /T-0-1] باید شامل پشتیبانی از حجم استاد سیستم و ضعف حجم صدا دیجیتال بر روی خروجی های پشتیبانی شده باشد ، به جز خروجی فشار صوتی فشرده شده (جایی که هیچ رمزگشایی صوتی روی دستگاه انجام نمی شود).
اگر پیاده سازی دستگاه های تلویزیونی دارای نمایشگر در صفحه نمایش نیست ، اما در عوض از یک صفحه نمایش خارجی که از طریق HDMI متصل است ، پشتیبانی می کنند ، آنها:
- [ 5.8 /T-0-1] باید حالت خروجی HDMI را تنظیم کند تا حداکثر وضوح را که می تواند با نرخ تازه سازی 50Hz یا 60Hz پشتیبانی کند ، انتخاب کند.
- [ 5.8 /T-SR-1] به شدت توصیه می شود که یک انتخاب کننده نرخ تازه سازی HDMI قابل تنظیم کاربر را ارائه دهید.
- [ 5.8 ] بسته به میزان تازه کردن ویدیو برای منطقه ای که دستگاه در آن فروخته می شود ، باید نرخ تازه کردن حالت خروجی HDMI را روی 50Hz یا 60Hz تنظیم کنید.
اگر پیاده سازی دستگاه های تلویزیونی دارای نمایشگر در صفحه نمایش نیست ، اما در عوض از یک صفحه نمایش خارجی که از طریق HDMI متصل است ، پشتیبانی می کنند ، آنها:
- [ 5.8 /T-1-1] باید از HDCP 2.2 پشتیبانی کند.
اگر پیاده سازی دستگاه های تلویزیونی از رمزگشایی UHD پشتیبانی نمی کنند ، بلکه در عوض از یک صفحه نمایش خارجی که از طریق HDMI متصل است پشتیبانی می کنند ، آنها:
- [ 5.8 /T-2-1] باید از HDCP 1.4 پشتیبانی کند
2.3.3. نرم افزار
پیاده سازی دستگاه های تلویزیونی:
- [ 3 /T-0-1] باید ویژگی های
android.software.leanback
وandroid.hardware.type.television
را اعلام کند. - [ 3.2.3.1 /T-0-1] باید یک یا چند برنامه یا مؤلفه های خدمات را با یک کنترل کننده قصد بارگذاری کنید ، برای کلیه الگوهای فیلتر قصد عمومی که توسط اهداف برنامه زیر ذکر شده در اینجا تعریف شده است.
- [ 3.4 .1/T-0-1] باید یک اجرای کامل
android.webkit.Webview
API را ارائه دهد.
اگر پیاده سازی دستگاه های تلویزیونی اندرویدی از صفحه قفل پشتیبانی می کند ، آنها:
- [ 3.8 .10/T-1-1] باید اعلان های صفحه قفل از جمله الگوی اعلان رسانه را نمایش دهد.
پیاده سازی دستگاه های تلویزیونی:
- [ 3.8 .14/T-SR-1] به شدت توصیه می شود که از حالت چند پنجره تصویر در تصویر (PIP) پشتیبانی کنید.
- [ 3.10 /T-0-1] باید از خدمات دسترسی به شخص ثالث پشتیبانی کند.
- [ 3.10 /T-SR-1] به شدت توصیه می شود خدمات دسترسی را از پیش بارگیری در دستگاه قابل مقایسه با یا بیش از عملکرد دسترسی به سوئیچ و گفتگوی (برای زبانهای پشتیبانی شده توسط موتور متن به گفتار از پیش نصب شده) ارائه دهید. پروژه منبع باز Talkback .
اگر پیاده سازی دستگاه های تلویزیونی ویژگی android.hardware.audio.output
را گزارش کنید ، آنها:
- [ 3.11 /T-SR-1] به شدت توصیه می شود یک موتور TTS را که از زبانهای موجود در دستگاه پشتیبانی می کند ، درج کنید.
- [ 3.11 /T-1-1] باید از نصب موتورهای TTS شخص ثالث پشتیبانی کند.
پیاده سازی دستگاه های تلویزیونی:
- [ 3.12 /T-0-1] باید از چارچوب ورودی تلویزیون پشتیبانی کند.
2.3.4. عملکرد و قدرت
- [ 8.1 /T-0-1] تأخیر قاب ثابت . تأخیر قاب متناقض یا تأخیر در ارائه فریم ها نباید بیشتر از 5 فریم در ثانیه اتفاق بیفتد و در یک ثانیه باید زیر 1 فریم باشد.
- [ 8.2 /T-0-1] باید عملکرد نوشتن متوالی حداقل 5MB /s را تضمین کند.
- [ 8.2 /T-0-2] باید عملکرد نوشتن تصادفی حداقل 0.5 مگابایت در ثانیه را تضمین کند.
- [ 8.2 /T-0-3] باید عملکرد خواندن متوالی حداقل 15MB /s را تضمین کند.
- [ 8.2 /T-0-4] باید عملکرد خواندن تصادفی حداقل 3.5 مگابایت در ثانیه را تضمین کند.
اگر پیاده سازی دستگاه های تلویزیونی شامل ویژگی هایی برای بهبود مدیریت انرژی دستگاه است که در AOSP گنجانده شده یا ویژگی هایی را که در AOSP گنجانده شده است ، گسترش می دهند ، آنها:
- [ 8.3 /t-1-1] برای فعال کردن و غیرفعال کردن ویژگی محافظ باتری باید هزینه کاربر را فراهم کند.
اگر پیاده سازی دستگاه های تلویزیونی باتری نداشته باشد:
- [ 8.3 /t-1-2] باید دستگاه را به عنوان یک دستگاه بدون باتری ثبت کنید ، همانطور که در پشتیبانی از دستگاه های بدون باتری توضیح داده شده است.
اگر پیاده سازی دستگاه های تلویزیونی باتری داشته باشد:
- [ 8.3 /t-1-3] باید هزینه کاربر را برای نمایش کلیه برنامه هایی که از حالت آماده به کار برنامه و حالت های صرفه جویی در مصرف برق استفاده می کنند ، فراهم کند.
پیاده سازی دستگاه های تلویزیونی:
- [ 8.4 /T-0-1] باید یک پروفایل قدرت در هر جزء را ارائه دهد که مقدار مصرف فعلی را برای هر مؤلفه سخت افزاری و تخلیه تقریبی باتری ناشی از قطعات به مرور زمان مشخص می کند ، همانطور که در سایت پروژه منبع باز اندروید ثبت شده است.
- [ 8.4 /T-0-2] باید تمام مقادیر مصرف برق را در ساعات میلی لیتر (MAH) گزارش دهد.
- [ 8.4 /T-0-3] باید مصرف انرژی CPU را در مورد UID هر فرآیند گزارش دهد. پروژه منبع باز اندروید از طریق اجرای ماژول هسته
uid_cputime
با این نیاز برآورده می شود. - [ 8.4 /t] در صورت عدم امکان استفاده از انرژی مؤلفه سخت افزاری به یک برنامه ، باید به خود مؤلفه سخت افزار نسبت داده شود.
- [ 8.4 /T-0-4] باید این استفاده از قدرت را از طریق دستور
adb shell dumpsys batterystats
Shell Dumpsys به توسعه دهنده برنامه در دسترس قرار دهد.
2.3.5. مدل امنیتی
پیاده سازی دستگاه های تلویزیونی:
- [ 9.11 /T-0-1] باید از اجرای کلیدی با یک محیط اجرای جدا شده پشتیبان تهیه کنید.
- [ 9.11 /T-0-2] باید اجرای الگوریتم های رمزنگاری RSA ، AES ، ECDSA و HMAC و عملکردهای هش خانوادگی MD5 ، SHA1 و SHA-2 برای پشتیبانی صحیح از الگوریتم های پشتیبانی شده سیستم کلیدی اندرویدی در منطقه ای که به طور ایمن جدا شده است ، داشته باشد. از کد در حال اجرا بر روی هسته و بالاتر. جداسازی ایمن باید تمام مکانیسم های بالقوه را که توسط آن هسته یا کد فضای کاربری ممکن است به وضعیت داخلی محیط جدا شده ، از جمله DMA دسترسی داشته باشد ، مسدود کند. پروژه منبع باز اندرویدی بالادست (AOSP) با استفاده از اجرای قابل اعتماد ، این نیاز را برآورده می کند ، اما یک راه حل مبتنی بر ARM TrustZone یا یک شخص ثالث اجرای ایمن یک جداسازی مناسب مبتنی بر Hypervisor گزینه های جایگزین است.
- [ 9.11 /T-0-3] باید احراز هویت صفحه قفل را در محیط اجرای جدا شده انجام دهد و فقط در صورت موفقیت ، اجازه دهید از کلیدهای محدود به تأیید اعتبار استفاده شود. اعتبارنامه صفحه قفل باید به گونه ای ذخیره شود که فقط به محیط اجرای جدا شده اجازه می دهد تا احراز هویت صفحه قفل را انجام دهد. پروژه منبع باز اندرویدی بالادست ، لایه انتزاع سخت افزار Gatekeeper (HAL) و قابل اعتماد را فراهم می کند که می تواند برای برآورده کردن این نیاز استفاده شود.
- [ 9.11 /T-0-4] باید از تأیید کلید پشتیبانی کند که در آن کلید امضاء تأیید شده توسط سخت افزار ایمن محافظت می شود و امضای آن در سخت افزار ایمن انجام می شود. کلیدهای امضای تأیید باید در تعداد کافی از دستگاه ها به اشتراک گذاشته شوند تا از استفاده کلیدها به عنوان شناسه دستگاه جلوگیری شود. یکی از راه های تأمین این شرط ، به اشتراک گذاشتن همان کلید تأیید است ، مگر اینکه حداقل 100000 واحد از یک SKU معین تولید شود. اگر بیش از 100000 واحد SKU تولید شود ، ممکن است برای هر 100000 واحد از یک کلید متفاوت استفاده شود.
- [9/T-0-1] باید ویژگی "android.hardware.security.model.compative" را اعلام کند.
توجه داشته باشید که اگر اجرای دستگاه در حال حاضر بر روی نسخه قبلی Android راه اندازی شده باشد ، چنین دستگاهی از الزام داشتن یک کلیدی پشتیبانی شده توسط یک محیط اجرای جدا شده معاف است و از تأیید کلید پشتیبانی می کند ، مگر اینکه ویژگی android.hardware.fingerprint
را اعلام کند که کدام یک از ویژگی های Android. نیاز به یک کلبه کلیدی دارد که توسط یک محیط اعدام منزوی پشتیبانی می شود.
اگر پیاده سازی دستگاه های تلویزیونی از صفحه قفل ایمن پشتیبانی می کند ، آنها:
- [ 9.11 /t-1-1] باید به کاربر اجازه دهد تا زمان خواب را برای انتقال از قفل به حالت قفل شده ، با حداقل زمان مجاز مجاز تا 15 ثانیه یا کمتر انتخاب کند.
اگر پیاده سازی دستگاه های تلویزیونی شامل چندین کاربر است و پرچم ویژگی android.hardware.telephony
را اعلام نکنید ، آنها:
- [ 9.5 /T-2-1] باید از پروفایل های محدود پشتیبانی کند ، ویژگی ای که به صاحبان دستگاه اجازه می دهد کاربران اضافی و قابلیت های آنها را در دستگاه مدیریت کنند. با پروفایل های محدود ، صاحبان دستگاه می توانند به سرعت محیط های جداگانه ای را برای کاربران اضافی تنظیم کنند ، با این امکان که بتوانند محدودیت های ریز ریز در برنامه هایی را که در آن محیط ها موجود است ، مدیریت کنند.
اگر پیاده سازی دستگاه های تلویزیونی شامل چندین کاربر است و پرچم ویژگی android.hardware.telephony
را اعلام کنید ، آنها:
- [ 9.5 /T-3-1] نباید از پروفایل های محدود پشتیبانی کند بلکه باید با اجرای AOSP کنترل ها هماهنگ باشد تا سایر کاربران را از دسترسی به تماس های صوتی و پیام کوتاه فعال یا غیرفعال کند.
اگر پیاده سازی دستگاه های تلویزیونی android.hardware.microphone
اعلام کنید ، آنها:
- [ 9.8.2 /T-4-1] باید هنگام دسترسی به داده های صوتی از میکروفون ، نشانگر میکروفون را نمایش دهد ، اما نه وقتی میکروفون فقط توسط hotworddetectionservice ، source_hotword ، contentCapturesRevice یا برنامه هایی که نقش هایی را در اختیار دارند ، دسترسی پیدا می کنند. بخش 9.1 مجوزها با شناسه CDD C-3-X].
- [ 9.8.2 /T-4-2] نباید نشانگر میکروفون را برای برنامه های سیستم که دارای رابط های کاربر قابل مشاهده یا تعامل مستقیم کاربر هستند ، پنهان کند.
اگر پیاده سازی دستگاه های تلویزیونی android.hardware.camera.any
را اعلام کنید ، آنها:
- [ 9.8.2 /T-5-1] باید هنگام دسترسی به داده های دوربین زنده ، نشانگر دوربین را نمایش دهد ، اما نه وقتی دوربین فقط توسط برنامه (ها) که نقش های نامیده شده در بخش 9.1 مجوزهای CDD را در اختیار شما قرار می دهد ، دسترسی پیدا نمی کند. شناسه [C-3-X].
- [ 9.8.2 /T-5-2] نباید نشانگر دوربین را برای برنامه های سیستم که دارای رابط های کاربر قابل مشاهده یا تعامل کاربر هستند ، پنهان کند.
2.3.6. ابزارهای توسعه دهنده و سازگاری گزینه ها
پیاده سازی دستگاه های تلویزیونی:
- پرفراتو
- [ 6.1 /T-0-1] MUST expose a
/system/bin/perfetto
binary to the shell user which cmdline complies with the perfetto documentation . - [ 6.1 /T-0-2] The perfetto binary MUST accept as input a protobuf config that complies with the schema defined in the perfetto documentation .
- [ 6.1 /T-0-3] The perfetto binary MUST write as output a protobuf trace that complies with the schema defined in the perfetto documentation .
- [ 6.1 /T-0-4] MUST provide, through the perfetto binary, at least the data sources described in the perfetto documentation .
- [ 6.1 /T-0-1] MUST expose a
2.4. Watch Requirements
An Android Watch device refers to an Android device implementation intended to be worn on the body, perhaps on the wrist.
Android device implementations are classified as a Watch if they meet all the following criteria:
- Have a screen with the physical diagonal length in the range from 1.1 to 2.5 inches.
- Have a mechanism provided to be worn on the body.
The additional requirements in the rest of this section are specific to Android Watch device implementations.
2.4.1. سخت افزار
Watch device implementations:
[ 7.1 .1.1/W-0-1] MUST have a screen with the physical diagonal size in the range from 1.1 to 2.5 inches.
[ 7.2 .3/W-0-1] MUST have the Home function available to the user, and the Back function except for when it is in
UI_MODE_TYPE_WATCH
.[ 7.2 .4/W-0-1] MUST support touchscreen input.
[ 7.3 .1/W-SR-1] Are STRONGLY RECOMMENDED to include a 3-axis accelerometer.
If Watch device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps
feature flag, they:
- [ 7.3 .3/W-1-1] MUST report GNSS measurements, as soon as they are found, even if a location calculated from GPS/GNSS is not yet reported.
- [ 7.3 .3/W-1-2] MUST report GNSS pseudoranges and pseudorange rates, that, in open-sky conditions after determining the location, while stationary or moving with less than 0.2 meter per second squared of acceleration, are sufficient to calculate position within 20 meters, and speed within 0.2 meters per second, at least 95% of the time.
If Watch device implementations include a 3-axis gyroscope, they:
- [ 7.3 .4/W-2-1] MUST be capable of measuring orientation changes up to 1000 degrees per second.
Watch device implementations:
[ 7.4 .3/W-0-1] MUST support Bluetooth.
[ 7.6 .1/W-0-1] MUST have at least 1 GB of non-volatile storage available for application private data (aka "/data" partition).
[ 7.6 .1/W-0-2] MUST have at least 416 MB memory available to the kernel and userspace.
[ 7.8 .1/W-0-1] MUST include a microphone.
[ 7.8 .2/W] MAY have audio output.
2.4.2. چند رسانه ای
No additional requirements.
2.4.3. نرم افزار
Watch device implementations:
- [ 3 /W-0-1] MUST declare the feature
android.hardware.type.watch
. - [ 3 /W-0-2] MUST support uiMode = UI_MODE_TYPE_WATCH .
- [ 3.2.3.1 /W-0-1] MUST preload one or more applications or service components with an intent handler, for all the public intent filter patterns defined by the following application intents listed here .
Watch device implementations:
- [ 3.8 .4/W-SR-1] Are STRONGLY RECOMMENDED to implement an assistant on the device to handle the Assist action .
Watch device implementations that declare the android.hardware.audio.output
feature flag:
- [ 3.10 /W-1-1] MUST support third-party accessibility services.
- [ 3.10 /W-SR-1] Are STRONGLY RECOMMENDED to preload accessibility services on the device comparable with or exceeding functionality of the Switch Access and TalkBack (for languages supported by the preinstalled Text-to-speech engine) accessibility services as provided in the talkback open source project .
If Watch device implementations report the feature android.hardware.audio.output, they:
[ 3.11 /W-SR-1] Are STRONGLY RECOMMENDED to include a TTS engine supporting the languages available on the device.
[ 3.11 /W-0-1] MUST support installation of third-party TTS engines.
2.4.4. Performance and Power
If Watch device implementations include features to improve device power management that are included in AOSP or extend the features that are included in AOSP, they:
- [ 8.3 /W-SR-1] Are STRONGLY RECOMMENDED to provide user affordance to display all apps that are exempted from App Standby and Doze power-saving modes.
- [ 8.3 /W-SR-2] Are STRONGLY RECOMMENDED to provide user affordance to enable and disable the battery saver feature.
Watch device implementations:
- [ 8.4 /W-0-1] MUST provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site.
- [ 8.4 /W-0-2] MUST report all power consumption values in milliampere hours (mAh).
- [ 8.4 /W-0-3] MUST report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the
uid_cputime
kernel module implementation. - [ 8.4 /W-0-4] MUST make this power usage available via the
adb shell dumpsys batterystats
shell command to the app developer. - [ 8.4 /W] SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.
2.4.5. Security Model
Watch device implementations:
- [9/W-0-1] MUST declare the
android.hardware.security.model.compatible
feature.
If Watch device implementations include multiple users and do not declare the android.hardware.telephony
feature flag, they:
- [ 9.5 /W-1-1] MUST support restricted profiles, a feature that allows device owners to manage additional users and their capabilities on the device. With restricted profiles, device owners can quickly set up separate environments for additional users to work in, with the ability to manage finer-grained restrictions in the apps that are available in those environments.
If Watch device implementations include multiple users and declare the android.hardware.telephony
feature flag, they:
- [ 9.5 /W-2-1] MUST NOT support restricted profiles but MUST align with the AOSP implementation of controls to enable /disable other users from accessing the voice calls and SMS.
2.5. Automotive Requirements
Android Automotive implementation refers to a vehicle head unit running Android as an operating system for part or all of the system and/or infotainment functionality.
Android device implementations are classified as an Automotive if they declare the feature android.hardware.type.automotive
or meet all the following criteria.
- Are embedded as part of, or pluggable to, an automotive vehicle.
- Are using a screen in the driver's seat row as the primary display.
The additional requirements in the rest of this section are specific to Android Automotive device implementations.
2.5.1. سخت افزار
Automotive device implementations:
- [ 7.1 .1.1/A-0-1] MUST have a screen at least 6 inches in physical diagonal size.
[ 7.1 .1.1/A-0-2] MUST have a screen size layout of at least 750 dp x 480 dp.
[ 7.2 .3/A-0-1] MUST provide the Home function and MAY provide Back and Recent functions.
[ 7.2 .3/A-0-2] MUST send both the normal and long press event of the Back function (
KEYCODE_BACK
) to the foreground application.[ 7.3 /A-0-1] MUST implement and report
GEAR_SELECTION
,NIGHT_MODE
,PERF_VEHICLE_SPEED
andPARKING_BRAKE_ON
.[ 7.3 /A-0-2] The value of the
NIGHT_MODE
flag MUST be consistent with dashboard day/night mode and SHOULD be based on ambient light sensor input. The underlying ambient light sensor MAY be the same as Photometer .[ 7.3 /A-0-3] MUST provide sensor additional info field
TYPE_SENSOR_PLACEMENT
as part of SensorAdditionalInfo for every sensor provided.[ 7.3 /A-0-1] MAY dead reckon Location by fusing GPS/GNSS with additional sensors. If Location is dead reckoned, it is STRONGLY RECOMMENDED to implement and report the corresponding Sensor types and/or Vehicle Property IDs used.
[ 7.3 /A-0-2] The Location requested via LocationManager#requestLocationUpdates() MUST NOT be map matched.
If Automotive device implementations support OpenGL ES 3.1, they:
- [ 7.1 .4.1/A-0-1] MUST declare OpenGL ES 3.1 or higher.
- [ 7.1 .4.1/A-0-2] MUST support Vulkan 1.1.
- [ 7.1 .4.1/A-0-3] MUST include Vulkan loader and export all symbols.
If Automotive device implementations include a 3-axis accelerometer, they:
- [ 7.3 .1/A-1-1] MUST be able to report events up to a frequency of at least 100 Hz.
- [ 7.3 .1/A-1-2] MUST comply with the Android car sensor coordinate system .
If Automotive device implementations include a 3-axis gyroscope, they:
- [ 7.3 .4/A-2-1] MUST be able to report events up to a frequency of at least 100 Hz.
- [ 7.3 .4/A-2-3] MUST be capable of measuring orientation changes up to 250 degrees per second.
- [ 7.3 .4/A-SR-1] Are STRONGLY RECOMMENDED to configure the gyroscope's measurement range to +/-250dps in order to maximize the resolution possible
If Automotive device implementations include a GPS/GNSS receiver, but do not include cellular network-based data connectivity, they:
- [ 7.3 .3/A-3-1] MUST determine location the very first time the GPS/GNSS receiver is turned on or after 4+ days within 60 seconds.
- [ 7.3 .3/A-3-2] MUST meet the time-to-first-fix criteria as described in 7.3.3/C-1-2 and 7.3.3/C-1-6 for all other location requests (ie requests which are not the first time ever or after 4+ days). The requirement 7.3.3/C-1-2 is typically met in vehicles without cellular network-based data connectivity, by using GNSS orbit predictions calculated on the receiver, or using the last known vehicle location along with the ability to dead reckon for at least 60 seconds with a position accuracy satisfying 7.3.3/C-1-3 , or a combination of both.
Automotive device implementations:
- [ 7.4 .3/A-0-1] MUST support Bluetooth and SHOULD support Bluetooth LE.
- [ 7.4 .3/A-0-2] Android Automotive implementations MUST support the following Bluetooth profiles:
- Phone calling over Hands-Free Profile (HFP).
- Media playback over Audio Distribution Profile (A2DP).
- Media playback control over Remote Control Profile (AVRCP).
- Contact sharing using the Phone Book Access Profile (PBAP).
[ 7.4 .3/A-SR-1] Are STRONGLY RECOMMENDED to support Message Access Profile (MAP).
[ 7.4 .5/A] SHOULD include support for cellular network-based data connectivity.
[ 7.4 .5/A] MAY use the System API
NetworkCapabilities#NET_CAPABILITY_OEM_PAID
constant for networks that should be available to system apps.
An exterior view camera is a camera that images scenes outside of the device implementation, like a dashcam.
Automotive device implementations:
- SHOULD include one or more exterior view cameras.
If Automotive device implementations include an exterior view camera, for such a camera, they:
- [ 7.5 /A-1-1] MUST NOT have exterior view cameras accessible via the Android Camera APIs , unless they comply with camera core requirements .
- [ 7.5 /A-SR-1] Are STRONGLY RECOMMENDED not to rotate or horizontally mirror the camera preview.
- [ 7.5 .5/A-SR-1] Are STRONGLY RECOMMENDED to be oriented so that the long dimension of the camera aligns with the horizon.
- [ 7.5 /A-SR-2] Are STRONGLY RECOMMENDED to have a resolution of at least 1.3 megapixels.
- SHOULD have either fixed-focus or EDOF (extended depth of field) hardware.
- SHOULD support Android synchronization framework .
- MAY have either hardware auto-focus or software auto-focus implemented in the camera driver.
Automotive device implementations:
[ 7.6 .1/A-0-1] MUST have at least 4 GB of non-volatile storage available for application private data (aka "/data" partition).
[ 7.6 .1/A] SHOULD format the data partition to offer improved performance and longevity on flash storage, for example using
f2fs
file-system.
If Automotive device implementations provide shared external storage via a portion of the internal non-removable storage, they:
- [ 7.6 .1/A-SR-1] Are STRONGLY RECOMMENDED to reduce I/O overhead on operations performed on the external storage, for example by using
SDCardFS
.
If Automotive device implementations are 32-bit:
[ 7.6 .1/A-1-1] The memory available to the kernel and userspace MUST be at least 512MB if any of the following densities are used:
- 280dpi or lower on small/normal screens
- ldpi or lower on extra large screens
- mdpi or lower on large screens
[ 7.6 .1/A-1-2] The memory available to the kernel and userspace MUST be at least 608MB if any of the following densities are used:
- xhdpi or higher on small/normal screens
- hdpi or higher on large screens
- mdpi or higher on extra large screens
[ 7.6 .1/A-1-3] The memory available to the kernel and userspace MUST be at least 896MB if any of the following densities are used:
- 400dpi or higher on small/normal screens
- xhdpi or higher on large screens
- tvdpi or higher on extra large screens
[ 7.6 .1/A-1-4] The memory available to the kernel and userspace MUST be at least 1344MB if any of the following densities are used:
- 560dpi or higher on small/normal screens
- 400dpi or higher on large screens
- xhdpi or higher on extra large screens
If Automotive device implementations are 64-bit:
[ 7.6 .1/A-2-1] The memory available to the kernel and userspace MUST be at least 816MB if any of the following densities are used:
- 280dpi or lower on small/normal screens
- ldpi or lower on extra large screens
- mdpi or lower on large screens
[ 7.6 .1/A-2-2] The memory available to the kernel and userspace MUST be at least 944MB if any of the following densities are used:
- xhdpi or higher on small/normal screens
- hdpi or higher on large screens
- mdpi or higher on extra large screens
[ 7.6 .1/A-2-3] The memory available to the kernel and userspace MUST be at least 1280MB if any of the following densities are used:
- 400dpi or higher on small/normal screens
- xhdpi or higher on large screens
- tvdpi or higher on extra large screens
[ 7.6 .1/A-2-4] The memory available to the kernel and userspace MUST be at least 1824MB if any of the following densities are used:
- 560dpi or higher on small/normal screens
- 400dpi or higher on large screens
- xhdpi or higher on extra large screens
Note that the "memory available to the kernel and userspace" above refers to the memory space provided in addition to any memory already dedicated to hardware components such as radio, video, and so on that are not under the kernel's control on device implementations.
Automotive device implementations:
- [ 7.7 .1/A] SHOULD include a USB port supporting peripheral mode.
Automotive device implementations:
- [ 7.8 .1/A-0-1] MUST include a microphone.
Automotive device implementations:
- [ 7.8 .2/A-0-1] MUST have an audio output and declare
android.hardware.audio.output
.
2.5.2. چند رسانه ای
Automotive device implementations MUST support the following audio encoding and decoding formats and make them available to third-party applications:
- [ 5.1 /A-0-1] MPEG-4 AAC Profile (AAC LC)
- [ 5.1 /A-0-2] MPEG-4 HE AAC Profile (AAC+)
- [ 5.1 /A-0-3] AAC ELD (enhanced low delay AAC)
Automotive device implementations MUST support the following video encoding formats and make them available to third-party applications:
Automotive device implementations MUST support the following video decoding formats and make them available to third-party applications:
Automotive device implementations are STRONGLY RECOMMENDED to support the following video decoding:
- [ 5.3 /A-SR-1] H.265 HEVC
2.5.3. نرم افزار
Automotive device implementations:
[ 3 /A-0-1] MUST declare the feature
android.hardware.type.automotive
.[ 3 /A-0-2] MUST support uiMode =
UI_MODE_TYPE_CAR
.[ 3 /A-0-3] MUST support all public APIs in the
android.car.*
namespace.
If Automotive device implementations provide a proprietary API using android.car.CarPropertyManager
with android.car.VehiclePropertyIds
, they:
- [ 3 /A-1-1] MUST NOT attach special privileges to system application's use of these properties, or prevent third-party applications from using these properties.
- [ 3 /A-1-2] MUST NOT replicate a vehicle property that already exists in the SDK .
Automotive device implementations:
[ 3.2 .1/A-0-1] MUST support and enforce all permissions constants as documented by the Automotive Permission reference page .
[ 3.2.3.1 /A-0-1] MUST preload one or more applications or service components with an intent handler, for all the public intent filter patterns defined by the following application intents listed here .
[ 3.4 .1/A-0-1] MUST provide a complete implementation of the
android.webkit.Webview
API.[ 3.8 .3/A-0-1] MUST display notifications that use the
Notification.CarExtender
API when requested by third-party applications.[ 3.8 .4/A-SR-1] Are STRONGLY RECOMMENDED to implement an assistant on the device to handle the Assist action .
If Automotive device implementations include a push-to-talk button, they:
- [ 3.8 .4/A-1-1] MUST use a short press of the push-to-talk button as the designated interaction to launch the user-selected assist app, in other words the app that implements
VoiceInteractionService
.
Automotive device implementations:
- [ 3.8.3.1 /A-0-1] MUST correctly render resources as described in the
Notifications on Automotive OS
SDK documentation. - [ 3.8.3.1 /A-0-2] MUST display PLAY and MUTE for notification actions in the place of those provided through
Notification.Builder.addAction()
- [ 3.8.3.1 /A] SHOULD restrict the use of rich management tasks such as per-notification-channel controls. MAY use UI affordance per application to reduce controls.
If Automotive device implementations support User HAL properties, they:
- [ 3.9.3 /A-1-1] MUST implement all of the User lifecycle properties
-
INITIAL_USER_INFO
,SWITCH_USER
,CREATE_USER
,REMOVE_USER
.
-
Automotive device implementations:
- [ 3.14 /A-0-1] MUST include a UI framework to support third-party apps using the media APIs as described in section 3.14 .
- [ 3.14 /A-0-2] MUST allow the user to safely interact with Media Applications while driving.
- [ 3.14 /A-0-3] MUST support the
CAR_INTENT_ACTION_MEDIA_TEMPLATE
implicit Intent action with theCAR_EXTRA_MEDIA_PACKAGE
extra. - [ 3.14 /A-0-4] MUST provide an affordance to navigate into a Media Application's preference activity , but MUST only enable it when Car UX Restrictions are not in effect.
- [ 3.14 /A-0-5] MUST display error messages set by Media Applications, and MUST support the optional extras
ERROR_RESOLUTION_ACTION_LABEL
andERROR_RESOLUTION_ACTION_INTENT
. - [ 3.14 /A-0-6] MUST support an in-app search affordance for apps that support searching.
- [ 3.14 /A-0-7] MUST respect
CONTENT_STYLE_BROWSABLE_HINT
andCONTENT_STYLE_PLAYABLE_HINT
definitions when displaying the MediaBrowser hierarchy.
If Automotive device implementations include a default launcher app, they:
- [ 3.14 /A-1-1] MUST include media services and open them with the
CAR_INTENT_ACTION_MEDIA_TEMPLATE
intent.
Automotive device implementations:
- [ 3.8 /A] MAY restrict the application requests to enter a full screen mode as described in
immersive documentation
. - [ 3.8 /A] MAY keep the status bar and the navigation bar visible at all times.
- [ 3.8 /A] MAY restrict the application requests to change the colors behind the system UI elements, to ensure those elements are clearly visible at all times.
2.5.4. Performance and Power
Automotive device implementations:
- [ 8.2 /A-0-1] MUST report the number of bytes read and written to non-volatile storage per each process's UID so the stats are available to developers through System API
android.car.storagemonitoring.CarStorageMonitoringManager
. The Android Open Source Project meets the requirement through theuid_sys_stats
kernel module. - [ 8.3 /A-1-3] MUST support Garage Mode .
- [ 8.3 /A] SHOULD be in Garage Mode for at least 15 minutes after every drive unless:
- The battery is drained.
- No idle jobs are scheduled.
- The driver exits Garage Mode.
- [ 8.4 /A-0-1] MUST provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site.
- [ 8.4 /A-0-2] MUST report all power consumption values in milliampere hours (mAh).
- [ 8.4 /A-0-3] MUST report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the
uid_cputime
kernel module implementation. - [ 8.4 /A] SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.
- [ 8.4 /A-0-4] MUST make this power usage available via the
adb shell dumpsys batterystats
shell command to the app developer.
2.5.5. Security Model
If Automotive device implementations support multiple users, they:
- [ 9.5 /A-1-1] MUST NOT allow users to interact with nor switch into the Headless System User , except for device provisioning .
- [ 9.5 /A-1-2] MUST switch into a Secondary User before
BOOT_COMPLETED
. - [ 9.5 /A-1-3] MUST support the ability to create a Guest User even when the maximum number of Users on a device has been reached.
Automotive device implementations:
- [ 9.11 /A-0-1] MUST back up the keystore implementation with an isolated execution environment.
- [ 9.11 /A-0-2] MUST have implementations of RSA, AES, ECDSA and HMAC cryptographic algorithms and MD5, SHA1, and SHA-2 family hash functions to properly support the Android Keystore system's supported algorithms in an area that is securely isolated from the code running on the kernel and above. Secure isolation MUST block all potential mechanisms by which kernel or userspace code might access the internal state of the isolated environment, including DMA. The upstream Android Open Source Project (AOSP) meets this requirement by using the Trusty implementation, but another ARM TrustZone-based solution or a third-party reviewed secure implementation of a proper hypervisor-based isolation are alternative options.
- [ 9.11 /A-0-3] MUST perform the lock screen authentication in the isolated execution environment and only when successful, allow the authentication-bound keys to be used. Lock screen credentials MUST be stored in a way that allows only the isolated execution environment to perform lock screen authentication. The upstream Android Open Source Project provides the Gatekeeper Hardware Abstraction Layer (HAL) and Trusty, which can be used to satisfy this requirement.
- [ 9.11 /A-0-4] MUST support key attestation where the attestation signing key is protected by secure hardware and signing is performed in secure hardware. The attestation signing keys MUST be shared across large enough number of devices to prevent the keys from being used as device identifiers. One way of meeting this requirement is to share the same attestation key unless at least 100,000 units of a given SKU are produced. If more than 100,000 units of an SKU are produced, a different key MAY be used for each 100,000 units.
- [9/A-0-1] MUST declare the 'android.hardware.security.model.compatible' feature.
Note that if a device implementation is already launched on an earlier Android version, such a device is exempted from the requirement to have a keystore backed by an isolated execution environment and support the key attestation, unless it declares the android.hardware.fingerprint
feature which requires a keystore backed by an isolated execution environment.
Automotive device implementations:
- [ 9.14 /A-0-1] MUST gatekeep messages from Android framework vehicle subsystems, eg, allowlisting permitted message types and message sources.
- [ 9.14 /A-0-2] MUST watchdog against denial of service attacks from the Android framework or third-party apps. This guards against malicious software flooding the vehicle network with traffic, which may lead to malfunctioning vehicle subsystems.
2.5.6. Developer Tools and Options Compatibility
Automotive device implementations:
- Perfetto
- [ 6.1 /A-0-1] MUST expose a
/system/bin/perfetto
binary to the shell user which cmdline complies with the perfetto documentation . - [ 6.1 /A-0-2] The perfetto binary MUST accept as input a protobuf config that complies with the schema defined in the perfetto documentation .
- [ 6.1 /A-0-3] The perfetto binary MUST write as output a protobuf trace that complies with the schema defined in the perfetto documentation .
- [ 6.1 /A-0-4] MUST provide, through the perfetto binary, at least the data sources described in the perfetto documentation .
- [ 6.1 /A-0-1] MUST expose a
2.6. Tablet Requirements
An Android Tablet device refers to an Android device implementation that typically meets all the following criteria:
- Used by holding in both hands.
- Does not have a clamshell or convertible configuration.
- Physical keyboard implementations used with the device connect by means of a standard connection (eg USB, Bluetooth).
- Has a power source that provides mobility, such as a battery.
- Has a screen display size greater than 7” and less than 18", measured diagonally.
Tablet device implementations have similar requirements to handheld device implementations. The exceptions are indicated by an * in that section and noted for reference in this section.
2.6.1. سخت افزار
ژیروسکوپ
If Tablet device implementations include a 3-axis gyroscope, they:
- [ 7.3 .4/Tab-1-1] MUST be capable of measuring orientation changes up to 1000 degrees per second.
Minimum Memory and Storage (Section 7.6.1)
The screen densities listed for small/normal screens in the handheld requirements are not applicable to tablets.
USB peripheral mode (Section 7.7.1)
If tablet device implementations include a USB port supporting peripheral mode, they:
- [ 7.7.1 /Tab] MAY implement the Android Open Accessory (AOA) API.
Virtual Reality Mode (Section 7.9.1)
Virtual Reality High Performance (Section 7.9.2)
Virtual reality requirements are not applicable to tablets.
2.6.2. Security Model
Keys and Credentials (Section 9.11)
Refer to Section [ 9.11 ].
If Tablet device implementations include multiple users and do not declare the android.hardware.telephony
feature flag, they:
- [ 9.5 /T-1-1] MUST support restricted profiles, a feature that allows device owners to manage additional users and their capabilities on the device. With restricted profiles, device owners can quickly set up separate environments for additional users to work in, with the ability to manage finer-grained restrictions in the apps that are available in those environments.
If Tablet device implementations include multiple users and declare the android.hardware.telephony
feature flag, they:
- [ 9.5 /T-2-1] MUST NOT support restricted profiles but MUST align with the AOSP implementation of controls to enable /disable other users from accessing the voice calls and SMS.
2.6.2. نرم افزار
- [ 3.2.3.1 /Tab-0-1] MUST preload one or more applications or service components with an intent handler, for all the public intent filter patterns defined by the following application intents listed here .
3. نرم افزار
3.1. Managed API Compatibility
The managed Dalvik bytecode execution environment is the primary vehicle for Android applications. The Android application programming interface (API) is the set of Android platform interfaces exposed to applications running in the managed runtime environment.
Device implementations:
[C-0-1] MUST provide complete implementations, including all documented behaviors, of any documented API exposed by the Android SDK or any API decorated with the “@SystemApi” marker in the upstream Android source code.
[C-0-2] MUST support/preserve all classes, methods, and associated elements marked by the TestApi annotation (@TestApi).
[C-0-3] MUST NOT omit any managed APIs, alter API interfaces or signatures, deviate from the documented behavior, or include no-ops, except where specifically allowed by this Compatibility Definition.
[C-0-4] MUST still keep the APIs present and behave in a reasonable way, even when some hardware features for which Android includes APIs are omitted. See section 7 for specific requirements for this scenario.
[C-0-5] MUST NOT allow third-party apps to use non-SDK interfaces, which are defined as methods and fields in the Java language packages that are in the boot classpath in AOSP, and that do not form part of the public SDK. This includes APIs decorated with the
@hide
annotation but not with a@SystemAPI
, as described in the SDK documents and private and package-private class members.[C-0-6] MUST ship with each and every non-SDK interface on the same restricted lists as provided via the provisional and denylist flags in
prebuilts/runtime/appcompat/hiddenapi-flags.csv
path for the appropriate API level branch in the AOSP.[C-0-7] MUST support the signed config dynamic update mechanism to remove non-SDK interfaces from a restricted list by embedding signed configuration in any APK, using the existing public keys present in AOSP.
However they:
- MAY, if a hidden API is absent or implemented differently on the device implementation, move the hidden API into the denylist or omit it from all restricted lists.
- MAY, if a hidden API does not already exist in the AOSP, add the hidden API to any of the restricted lists.
3.1.1. Android Extensions
Android supports extending the managed API surface of a particular API level by updating the extension version for that API level. The android.os.ext.SdkExtensions.getExtensionVersion(int apiLevel)
API returns the extension version of the provided apiLevel
, if there are extensions for that API level.
Android device implementations:
[C-0-1] MUST preload the AOSP implementation of both the shared library
ExtShared
and servicesExtServices
with versions greater than or equal to the minimum versions allowed per each API level. For example, Android 7.0 device implementations, running API level 24 MUST include at least version 1.[C-0-2] MUST only return valid extension version number that have been defined by the AOSP.
[C-0-3] MUST support all the APIs defined by the extension versions returned by
android.os.ext.SdkExtensions.getExtensionVersion(int apiLevel)
in the same manner as other managed APIs are supported, following the requirements in section 3.1 .
3.1.2. Android Library
Due to Apache HTTP client deprecation , device implementations:
- [C-0-1] MUST NOT place the
org.apache.http.legacy
library in the bootclasspath. - [C-0-2] MUST add the
org.apache.http.legacy
library to the application classpath only when the app satisfies one of the following conditions:- Targets API level 28 or lower.
- Declares in its manifest that it needs the library by setting the
android:name
attribute of<uses-library>
toorg.apache.http.legacy
.
The AOSP implementation meets these requirements.
3.2. Soft API Compatibility
In addition to the managed APIs from section 3.1 , Android also includes a significant runtime-only “soft” API, in the form of such things as intents, permissions, and similar aspects of Android applications that cannot be enforced at application compile time.
3.2.1. مجوزها
- [C-0-1] Device implementers MUST support and enforce all permission constants as documented by the Permission reference page . Note that section 9 lists additional requirements related to the Android security model.
3.2.2. Build Parameters
The Android APIs include a number of constants on the android.os.Build class that are intended to describe the current device.
- [C-0-1] To provide consistent, meaningful values across device implementations, the table below includes additional restrictions on the formats of these values to which device implementations MUST conform.
پارامتر | جزئیات |
---|---|
VERSION.RELEASE | The version of the currently-executing Android system, in human-readable format. This field MUST have one of the string values defined in Permitted Version Strings for Android 12 . |
VERSION.SDK | The version of the currently-executing Android system, in a format accessible to third-party application code. For Android 12, this field MUST have the integer value 12_INT. |
VERSION.SDK_INT | The version of the currently-executing Android system, in a format accessible to third-party application code. For Android 12, this field MUST have the integer value 12_INT. |
VERSION.INCREMENTAL | A value chosen by the device implementer designating the specific build of the currently-executing Android system, in human-readable format. This value MUST NOT be reused for different builds made available to end users. A typical use of this field is to indicate which build number or source-control change identifier was used to generate the build. The value of this field MUST be encodable as printable 7-bit ASCII and match the regular expression “^[^ :\/~]+$”. |
هیئت مدیره | A value chosen by the device implementer identifying the specific internal hardware used by the device, in human-readable format. A possible use of this field is to indicate the specific revision of the board powering the device. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9_-]+$”. |
برند | A value reflecting the brand name associated with the device as known to the end users. MUST be in human-readable format and SHOULD represent the manufacturer of the device or the company brand under which the device is marketed. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9_-]+$”. |
SUPPORTED_ABIS | The name of the instruction set (CPU type + ABI convention) of native code. See section 3.3. Native API Compatibility . |
SUPPORTED_32_BIT_ABIS | The name of the instruction set (CPU type + ABI convention) of native code. See section 3.3. Native API Compatibility . |
SUPPORTED_64_BIT_ABIS | The name of the second instruction set (CPU type + ABI convention) of native code. See section 3.3. Native API Compatibility . |
CPU_ABI | The name of the instruction set (CPU type + ABI convention) of native code. See section 3.3. Native API Compatibility . |
CPU_ABI2 | The name of the second instruction set (CPU type + ABI convention) of native code. See section 3.3. Native API Compatibility . |
DEVICE | A value chosen by the device implementer containing the development name or code name identifying the configuration of the hardware features and industrial design of the device. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9_-]+$”. This device name MUST NOT change during the lifetime of the product. |
FINGERPRINT | A string that uniquely identifies this build. It SHOULD be reasonably human-readable. It MUST follow this template: $(BRAND)/$(PRODUCT)/ به عنوان مثال: acme/myproduct/ The fingerprint MUST NOT include whitespace characters. The value of this field MUST be encodable as 7-bit ASCII. |
سخت افزار | The name of the hardware (from the kernel command line or /proc). It SHOULD be reasonably human-readable. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9_-]+$”. |
میزبان | A string that uniquely identifies the host the build was built on, in human-readable format. There are no requirements on the specific format of this field, except that it MUST NOT be null or the empty string (""). |
شناسه | An identifier chosen by the device implementer to refer to a specific release, in human-readable format. This field can be the same as android.os.Build.VERSION.INCREMENTAL, but SHOULD be a value sufficiently meaningful for end users to distinguish between software builds. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9._-]+$”. |
تولید کننده | The trade name of the Original Equipment Manufacturer (OEM) of the product. There are no requirements on the specific format of this field, except that it MUST NOT be null or the empty string (""). This field MUST NOT change during the lifetime of the product. |
SOC_MANUFACTURER | The trade of name of the manufacturer of the primary system on chip (SOC) used in the product. Devices with the same SOC manufacturer should use the same constant value. Please ask the SOC manufacturer for the correct constant to use. The value of this field MUST be encodable as 7-bit ASCII, MUST match the regular expression “^([0-9A-Za-z ]+)”, MUST NOT start or end with whitespace, and MUST NOT be equal to “unknown”. This field MUST NOT change during the lifetime of the product. |
SOC_MODEL | The model name of the primary system on a chip (SOC) used in the product. Devices with the same SOC model should use the same constant value. Please ask the SOC manufacturer for the correct constant to use. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^([0-9A-Za-z ._/+-]+)$”, MUST NOT start or end with whitespace, and MUST NOT be equal to “unknown”. This field MUST NOT change during the lifetime of the product. |
مدل | A value chosen by the device implementer containing the name of the device as known to the end user. This SHOULD be the same name under which the device is marketed and sold to end users. There are no requirements on the specific format of this field, except that it MUST NOT be null or the empty string (""). This field MUST NOT change during the lifetime of the product. |
محصول | A value chosen by the device implementer containing the development name or code name of the specific product (SKU) that MUST be unique within the same brand. MUST be human-readable, but is not necessarily intended for view by end users. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9_-]+$”. This product name MUST NOT change during the lifetime of the product. |
ODM_SKU | An optional value chosen by the device implementer that contains SKU (Stock Keeping Unit) used to track specific configurations of the device, for example, any peripherals included with the device when sold. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression ^([0-9A-Za-z.,_-]+)$ . |
SERIAL | MUST return "UNKNOWN". |
برچسب ها | A comma-separated list of tags chosen by the device implementer that further distinguishes the build. The tags MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9._-]+” and MUST have one of the values corresponding to the three typical Android platform signing configurations: release-keys, dev-keys, and test-keys. |
TIME | A value representing the timestamp of when the build occurred. |
تایپ کنید | A value chosen by the device implementer specifying the runtime configuration of the build. This field MUST have one of the values corresponding to the three typical Android runtime configurations: user, userdebug, or eng. |
کاربر | A name or user ID of the user (or automated user) that generated the build. There are no requirements on the specific format of this field, except that it MUST NOT be null or the empty string (""). |
SECURITY_PATCH | A value indicating the security patch level of a build. It MUST signify that the build is not in any way vulnerable to any of the issues described up through the designated Android Public Security Bulletin. It MUST be in the format [YYYY-MM-DD], matching a defined string documented in the Android Public Security Bulletin or in the Android Security Advisory , for example "2015-11-01". |
BASE_OS | A value representing the FINGERPRINT parameter of the build that is otherwise identical to this build except for the patches provided in the Android Public Security Bulletin. It MUST report the correct value and if such a build does not exist, report an empty string (""). |
بوت لودر | A value chosen by the device implementer identifying the specific internal bootloader version used in the device, in human-readable format. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9._-]+$”. |
getRadioVersion() | MUST (be or return) a value chosen by the device implementer identifying the specific internal radio/modem version used in the device, in human-readable format. If a device does not have any internal radio/modem it MUST return NULL. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9._-,]+$”. |
getSerial() | MUST (be or return) a hardware serial number, which MUST be available and unique across devices with the same MODEL and MANUFACTURER. The value of this field MUST be encodable as 7-bit ASCII and match the regular expression “^[a-zA-Z0-9._-,]+$”. |
3.2.3. Intent Compatibility
3.2.3.1. Common Application Intents
Android intents allow application components to request functionality from other Android components. The Android upstream project includes a list of applications which implement several intent patterns to perform common actions.
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to preload one or more applications or service components with an intent handler, for all the public intent filter patterns defined by the following application intents listed here and provide fulfillment ie meet with the developer expectation for these common application intents as described in the SDK.
Please refer to Section 2 for mandatory application intents for each device type.
3.2.3.2. Intent Resolution
[C-0-1] As Android is an extensible platform, device implementations MUST allow each intent pattern referenced in section 3.2.3.1 , except for Settings, to be overridden by third-party applications. The upstream Android open source implementation allows this by default.
[C-0-2] Device implementers MUST NOT attach special privileges to system applications' use of these intent patterns, or prevent third-party applications from binding to and assuming control of these patterns. This prohibition specifically includes but is not limited to disabling the “Chooser” user interface that allows the user to select between multiple applications that all handle the same intent pattern.
[C-0-3] Device implementations MUST provide a user interface for users to modify the default activity for intents.
However, device implementations MAY provide default activities for specific URI patterns (eg http://play.google.com) when the default activity provides a more specific attribute for the data URI. For example, an intent filter pattern specifying the data URI “http://www.android.com” is more specific than the browser's core intent pattern for “http://”.
Android also includes a mechanism for third-party apps to declare an authoritative default app linking behavior for certain types of web URI intents. When such authoritative declarations are defined in an app's intent filter patterns, device implementations:
- [C-0-4] MUST attempt to validate any intent filters by performing the validation steps defined in the Digital Asset Links specification as implemented by the Package Manager in the upstream Android Open Source Project.
- [C-0-5] MUST attempt validation of the intent filters during the installation of the application and set all successfully validated URI intent filters as default app handlers for their URIs.
- MAY set specific URI intent filters as default app handlers for their URIs, if they are successfully verified but other candidate URI filters fail verification. If a device implementation does this, it MUST provide the user appropriate per-URI pattern overrides in the settings menu.
- MUST provide the user with per-app App Links controls in Settings as follows:
- [C-0-6] The user MUST be able to override holistically the default app links behavior for an app to be: always open, always ask, or never open, which must apply to all candidate URI intent filters equally.
- [C-0-7] The user MUST be able to see a list of the candidate URI intent filters.
- The device implementation MAY provide the user with the ability to override specific candidate URI intent filters that were successfully verified, on a per-intent filter basis.
- [C-0-8] The device implementation MUST provide users with the ability to view and override specific candidate URI intent filters if the device implementation lets some candidate URI intent filters succeed verification while some others can fail.
3.2.3.3. Intent Namespaces
- [C-0-1] Device implementations MUST NOT include any Android component that honors any new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key string in the android.* or com.android.* namespace.
- [C-0-2] Device implementers MUST NOT include any Android components that honor any new intent or broadcast intent patterns using an ACTION, CATEGORY, or other key string in a package space belonging to another organization.
- [C-0-3] Device implementers MUST NOT alter or extend any of the intent patterns listed in section 3.2.3.1 .
- Device implementations MAY include intent patterns using namespaces clearly and obviously associated with their own organization. This prohibition is analogous to that specified for Java language classes in section 3.6 .
3.2.3.4. Broadcast Intents
Third-party applications rely on the platform to broadcast certain intents to notify them of changes in the hardware or software environment.
Device implementations:
- [C-0-1] MUST broadcast the public broadcast intents listed here in response to appropriate system events as described in the SDK documentation. Note that this requirement is not conflicting with section 3.5 as the limitation for background applications are also described in the SDK documentation. Also certain broadcast intents are conditional upon hardware support, if the device supports the necessary hardware they MUST broadcast the intents and provide the behavior inline with SDK documentation.
3.2.3.5. Conditional Application Intents
Android includes settings that provide users an easy way to select their default applications, for example for Home screen or SMS.
Where it makes sense, device implementations MUST provide a similar settings menu and be compatible with the intent filter pattern and API methods described in the SDK documentation as below.
If device implementations report android.software.home_screen
, they:
- [C-1-1] MUST honor the
android.settings.HOME_SETTINGS
intent to show a default app settings menu for Home Screen.
If device implementations report android.hardware.telephony
, they:
[C-2-1] MUST provide a settings menu that will call the
android.provider.Telephony.ACTION_CHANGE_DEFAULT
intent to show a dialog to change the default SMS application.[C-2-2] MUST honor the
android.telecom.action.CHANGE_DEFAULT_DIALER
intent to show a dialog to allow the user to change the default Phone application.- MUST use the user-selected default Phone app's UI for incoming and outgoing calls except for emergency calls, which would use the preinstalled Phone app.
[C-2-3] MUST honor the android.telecom.action.CHANGE_PHONE_ACCOUNTS intent to provide user affordance to configure the
ConnectionServices
associated with thePhoneAccounts
, as well as a default PhoneAccount that the telecommunications service provider will use to place outgoing calls. The AOSP implementation meets this requirement by including a "Calling Accounts option" menu within the "Calls" settings menu.[C-2-4] MUST allow
android.telecom.CallRedirectionService
for an app that holds theandroid.app.role.CALL_REDIRECTION
role.[C-2-5] MUST provide the user affordance to choose an app that holds the
android.app.role.CALL_REDIRECTION
role.[C-2-6] MUST honor the android.intent.action.SENDTO and android.intent.action.VIEW intents and provide an activity to send/display SMS messages.
[C-SR-1] Are STRONGLY RECOMMENDED to honor android.intent.action.ANSWER , android.intent.action.CALL , android.intent.action.CALL_BUTTON , android.intent.action.VIEW & android.intent.action.DIAL intents with a preloaded dialer application which can handle these intents and provide fulfillment as described in the SDK.
If device implementations report android.hardware.nfc.hce
, they:
- [C-3-1] MUST honor the android.settings.NFC_PAYMENT_SETTINGS intent to show a default app settings menu for Contactless payment.
- [C-3-2] MUST honor android.nfc.cardemulation.action.ACTION_CHANGE_DEFAULT intent to show an activity which opens a dialog to ask the user to change the default card emulation service for a certain category as described in the SDK.
If device implementations report android.hardware.nfc
, they:
- [C-4-1] MUST honor these intents android.nfc.action.NDEF_DISCOVERED , android.nfc.action.TAG_DISCOVERED & android.nfc.action.TECH_DISCOVERED , to show an activity which fulfils developer expectations for these intents as described in the SDK.
If device implementations report android.hardware.bluetooth
, they:
- [C-5-1] MUST honor the 'android.bluetooth.adapter.action.REQUEST_ENABLE' intent and show a system activity to allow the user to turn on Bluetooth.
- [C-5-2] MUST honor the 'android.bluetooth.adapter.action.REQUEST_DISCOVERABLE' intent and show a system activity that requests discoverable mode.
If device implementations support the DND feature, they:
- [C-6-1] MUST implement an activity that would respond to the intent
ACTION_NOTIFICATION_POLICY_ACCESS_SETTINGS
, which for implementations with UI_MODE_TYPE_NORMAL it MUST be an activity where the user can grant or deny the app access to DND policy configurations.
If device implementations allow users to use third-party input methods on the device, they:
- [C-7-1] MUST provide a user-accessible mechanism to add and configure third-party input methods in response to the
android.settings.INPUT_METHOD_SETTINGS
intent.
If device implementations support third-party accessibility services, they:
- [C-8-1] MUST honor the
android.settings.ACCESSIBILITY_SETTINGS
intent to provide a user-accessible mechanism to enable and disable the third-party accessibility services alongside the preloaded accessibility services.
If device implementations include support for Wi-Fi Easy Connect and expose the functionality to third-party apps, they:
- [C-9-1] MUST implement the Settings#ACTION_PROCESS_WIFI_EASY_CONNECT_URI Intent APIs as described in the SDK documentation.
If device implementations provide the data saver mode, they:
- [C-10-1] MUST provide a user interface in the settings, that handles the
Settings.ACTION_IGNORE_BACKGROUND_DATA_RESTRICTIONS_SETTINGS
intent, allowing users to add applications to or remove applications from the allow list.
If device implementations do not provide the data saver mode, they:
- [C-11-1] MUST have an activity that handles the
Settings.ACTION_IGNORE_BACKGROUND_DATA_RESTRICTIONS_SETTINGS
intent but MAY implement it as a no-op.
If device implementations declare the support for camera via android.hardware.camera.any
they:
- [C-12-3] MUST honor only allow preinstalled Android applications to handle the following intents
MediaStore.ACTION_IMAGE_CAPTURE
,MediaStore.ACTION_IMAGE_CAPTURE_SECURE
, andMediaStore.ACTION_VIDEO_CAPTURE
as described in the SDK document .
If device implementations report android.software.device_admin
, they:
[C-13-1] MUST honor the intent
android.app.action.ADD_DEVICE_ADMIN
to invoke a UI to bring the user through adding the device administrator to the system (or allowing them to reject it).[C-13-2] MUST honor the intents android.app.action.PROVISION_MANAGED_PROFILE , android.app.action.SET_NEW_PARENT_PROFILE_PASSWORD , android.app.action.SET_NEW_PASSWORD & android.app.action.START_ENCRYPTION and have an activity to provide fulfillment for these intents as described in SDK here .
If device implementations declare the android.software.autofill
feature flag, they:
- [C-14-1] MUST fully implement the
AutofillService
andAutofillManager
APIs and honor the android.settings.REQUEST_SET_AUTOFILL_SERVICE intent to show a default app settings menu to enable and disable autofill and change the default autofill service for the user.
If device implementations include a pre-installed app or wish to allow third-party apps to access the usage statistics, they:
- [C-SR-2] are STRONGLY RECOMMENDED provide user-accessible mechanism to grant or revoke access to the usage stats in response to the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent for apps that declare the
android.permission.PACKAGE_USAGE_STATS
permission.
If device implementations intend to disallow any apps, including pre-installed apps, from accessing the usage statistics, they:
- [C-15-1] MUST still have an activity that handles the android.settings.ACTION_USAGE_ACCESS_SETTINGS intent pattern but MUST implement it as a no-op, that is to have an equivalent behavior as when the user is declined for access.
If device implementations surface links to the activities specified by AutofillService_passwordsActivity in Settings or links to user passwords through a similar mechanism, they:
- [C-16-1] MUST surface such links for all installed autofill services.
If device implementations support the VoiceInteractionService
and have more than one application using this API installed at a time, they:
- [C-18-1] MUST honor the
android.settings.ACTION_VOICE_INPUT_SETTINGS
intent to show a default app settings menu for voice input and assist.
If device implementations report the feature android.hardware.audio.output
, they:
- [C-SR-3] Are STRONGLY RECOMMENDED to honor android.intent.action.TTS_SERVICE, android.speech.tts.engine.INSTALL_TTS_DATA & android.speech.tts.engine.GET_SAMPLE_TEXT intents have an activity to provide fulfillment for these intents as described in SDK here .
Android includes support for interactive screensavers, previously referred to as Dreams. Screen Savers allow users to interact with applications when a device connected to a power source is idle or docked in a desk dock. Device Implementations:
- SHOULD include support for screen savers and provide a settings option for users to configure screen savers in response to the
android.settings.DREAM_SETTINGS
intent.
3.2.4. Activities on secondary/multiple displays
If device implementations allow launching normal Android Activities on more than one display, they:
- [C-1-1] MUST set the
android.software.activities_on_secondary_displays
feature flag. - [C-1-2] MUST guarantee API compatibility similar to an activity running on the primary display.
- [C-1-3] MUST land the new activity on the same display as the activity that launched it, when the new activity is launched without specifying a target display via the
ActivityOptions.setLaunchDisplayId()
API. - [C-1-4] MUST destroy all activities, when a display with the
Display.FLAG_PRIVATE
flag is removed. - [C-1-5] MUST securely hide content on all screens when the device is locked with a secure lock screen, unless the app opts in to show on top of lock screen using
Activity#setShowWhenLocked()
API. - SHOULD have
android.content.res.Configuration
which corresponds to that display in order to be displayed, operate correctly, and maintain compatibility if an activity is launched on secondary display.
If device implementations allow launching normal Android Activities on secondary displays and a secondary display has the android.view.Display.FLAG_PRIVATE flag:
- [C-3-1] Only the owner of that display, system, and activities that are already on that display MUST be able to launch to it. Everyone can launch to a display that has android.view.Display.FLAG_PUBLIC flag.
3.3. Native API Compatibility
Native code compatibility is challenging. For this reason, device implementers are:
- [C-SR-1] STRONGLY RECOMMENDED to use the implementations of the libraries listed below from the upstream Android Open Source Project.
3.3.1. Application Binary Interfaces
Managed Dalvik bytecode can call into native code provided in the application .apk
file as an ELF .so
file compiled for the appropriate device hardware architecture. As native code is highly dependent on the underlying processor technology, Android defines a number of Application Binary Interfaces (ABIs) in the Android NDK.
Device implementations:
- [C-0-1] MUST be compatible with one or more defined Android NDK ABIs .
- [C-0-2] MUST include support for code running in the managed environment to call into native code, using the standard Java Native Interface (JNI) semantics.
- [C-0-3] MUST be source-compatible (ie header-compatible) and binary-compatible (for the ABI) with each required library in the list below.
- [C-0-5] MUST accurately report the native Application Binary Interface (ABI) supported by the device, via the
android.os.Build.SUPPORTED_ABIS
,android.os.Build.SUPPORTED_32_BIT_ABIS
, andandroid.os.Build.SUPPORTED_64_BIT_ABIS
parameters, each a comma separated list of ABIs ordered from the most to the least preferred one. [C-0-6] MUST report, via the above parameters, a subset of the following list of ABIs and MUST NOT report any ABI not on the list.
-
armeabi
(no longer supported as a target by the NDK) -
armeabi-v7a
-
arm64-v8a
-
x86
-
x86-64
-
[C-0-7] MUST make all the following libraries, providing native APIs, available to apps that include native code:
- libaaudio.so (AAudio native audio support)
- libamidi.so (native MIDI support, if feature
android.software.midi
is claimed as described in Section 5.9) - libandroid.so (native Android activity support)
- libc (C library)
- libcamera2ndk.so
- libdl (dynamic linker)
- libEGL.so (native OpenGL surface management)
- libGLESv1_CM.so (OpenGL ES 1.x)
- libGLESv2.so (OpenGL ES 2.0)
- libGLESv3.so (OpenGL ES 3.x)
- libicui18n.so
- libicuuc.so
- libjnigraphics.so
- liblog (Android logging)
- libmediandk.so (native media APIs support)
- libm (math library)
- libneuralnetworks.so (Neural Networks API)
- libOpenMAXAL.so (OpenMAX AL 1.0.1 support)
- libOpenSLES.so (OpenSL ES 1.0.1 audio support)
- libRS.so
- libstdc++ (Minimal support for C++)
- libvulkan.so (Vulkan)
- libz (Zlib compression)
- JNI interface
[C-0-8] MUST NOT add or remove the public functions for the native libraries listed above.
[C-0-9] MUST list additional non-AOSP libraries exposed directly to third-party apps in
/vendor/etc/public.libraries.txt
.[C-0-10] MUST NOT expose any other native libraries, implemented and provided in AOSP as system libraries, to third-party apps targeting API level 24 or higher as they are reserved.
[C-0-11] MUST export all the OpenGL ES 3.1 and Android Extension Pack function symbols, as defined in the NDK, through the
libGLESv3.so
library. Note that while all the symbols MUST be present, section 7.1.4.1 describes in more detail the requirements for when the full implementation of each corresponding functions are expected.[C-0-12] MUST export function symbols for the core Vulkan 1.0 function symbols, as well as the
VK_KHR_surface
,VK_KHR_android_surface
,VK_KHR_swapchain
,VK_KHR_maintenance1
, andVK_KHR_get_physical_device_properties2
extensions through thelibvulkan.so
library. Note that while all the symbols MUST be present, section 7.1.4.2 describes in more detail the requirements for when the full implementation of each corresponding functions are expected.SHOULD be built using the source code and header files available in the upstream Android Open Source Project
Note that future releases of Android may introduce support for additional ABIs.
3.3.2. 32-bit ARM Native Code Compatibility
If device implementations report the support of the armeabi
ABI, they:
- [C-3-1] MUST also support
armeabi-v7a
and report its support, asarmeabi
is only for backwards compatibility with older apps.
If device implementations report the support of the armeabi-v7a
ABI, for apps using this ABI, they:
[C-2-1] MUST include the following lines in
/proc/cpuinfo
, and SHOULD NOT alter the values on the same device, even when they are read by other ABIs.-
Features:
, followed by a list of any optional ARMv7 CPU features supported by the device. -
CPU architecture:
, followed by an integer describing the device's highest supported ARM architecture (eg, "8" for ARMv8 devices).
-
[C-2-2] MUST always keep the following operations available, even in the case where the ABI is implemented on an ARMv8 architecture, either through native CPU support or through software emulation:
- SWP and SWPB instructions.
- CP15ISB, CP15DSB, and CP15DMB barrier operations.
[C-2-3] MUST include support for the Advanced SIMD (aka NEON) extension.
3.4. Web Compatibility
3.4.1. WebView Compatibility
If device implementations provide a complete implementation of the android.webkit.Webview
API, they:
- [C-1-1] MUST report
android.software.webview
. - [C-1-2] MUST use the Chromium Project build from the upstream Android Open Source Project on the Android 12 branch for the implementation of the
android.webkit.WebView
API. [C-1-3] The user agent string reported by the WebView MUST be in this format:
Mozilla/5.0 (Linux; Android $(VERSION); [$(MODEL)] [Build/$(BUILD)]; wv) AppleWebKit/537.36 (KHTML, like Gecko) Version/4.0 $(CHROMIUM_VER) Mobile Safari/537.36
- The value of the $(VERSION) string MUST be the same as the value for android.os.Build.VERSION.RELEASE.
- The $(MODEL) string MAY be empty, but if it is not empty it MUST have the same value as android.os.Build.MODEL.
- "Build/$(BUILD)" MAY be omitted, but if it is present the $(BUILD) string MUST be the same as the value for android.os.Build.ID.
- The value of the $(CHROMIUM_VER) string MUST be the version of Chromium in the upstream Android Open Source Project.
- Device implementations MAY omit Mobile in the user agent string.
The WebView component SHOULD include support for as many HTML5 features as possible and if it supports the feature SHOULD conform to the HTML5 specification .
[C-1-4] MUST render the provided content or remote URL content in a process that is distinct from the application that instantiates the WebView. Specifically the separate renderer process MUST hold lower privilege, run as a separate user ID, have no access to the app's data directory, have no direct network access, and only have access to the minimum-required system services over Binder. The AOSP implementation of WebView meets this requirement.
Note that if device implementations are 32-bit or declare the feature flag android.hardware.ram.low
, they are exempted from C-1-3.
3.4.2. Browser Compatibility
If device implementations include a standalone Browser application for general web browsing, they:
- [C-1-1] MUST support each of these APIs associated with HTML5:
- [C-1-2] MUST support the HTML5/W3C webstorage API and SHOULD support the HTML5/W3C IndexedDB API . Note that as the web development standards bodies are transitioning to favor IndexedDB over webstorage, IndexedDB is expected to become a required component in a future version of Android.
- MAY ship a custom user agent string in the standalone Browser application.
- SHOULD implement support for as much of HTML5 as possible on the standalone Browser application (whether based on the upstream WebKit Browser application or a third-party replacement).
However, If device implementations do not include a standalone Browser application, they:
- [C-2-1] MUST still support the public intent patterns as described in section 3.2.3.1 .
3.5. API Behavioral Compatibility
Device implementations:
- [C-0-9] MUST ensure that API behavioral compatibility is applied for all installed apps unless they are restricted as described in Section 3.5.1 .
- [C-0-10] MUST NOT implement the allowlisting approach that ensures API behavioral compatibility only for apps that are selected by device implementers.
The behaviors of each of the API types (managed, soft, native, and web) must be consistent with the preferred implementation of the upstream Android Open Source Project . Some specific areas of compatibility are:
- [C-0-1] Devices MUST NOT change the behavior or semantics of a standard intent.
- [C-0-2] Devices MUST NOT alter the lifecycle or lifecycle semantics of a particular type of system component (such as Service, Activity, ContentProvider, etc.).
- [C-0-3] Devices MUST NOT change the semantics of a standard permission.
- Devices MUST NOT alter the limitations enforced on background applications. More specifically, for background apps:
- [C-0-4] they MUST stop executing callbacks that are registered by the app to receive outputs from the
GnssMeasurement
andGnssNavigationMessage
. - [C-0-5] they MUST rate-limit the frequency of updates that are provided to the app through the
LocationManager
API class or theWifiManager.startScan()
method. - [C-0-6] if the app is targeting API level 25 or higher, they MUST NOT allow to register broadcast receivers for the implicit broadcasts of standard Android intents in the app's manifest, unless the broadcast intent requires a
"signature"
or"signatureOrSystem"
protectionLevel
permission or are on the exemption list . - [C-0-7] if the app is targeting API level 25 or higher, they MUST stop the app's background services, just as if the app had called the services'
stopSelf()
method, unless the app is placed on a temporary allowlist to handle a task that's visible to the user. - [C-0-8] if the app is targeting API level 25 or higher, they MUST release the wakelocks the app holds.
- [C-0-4] they MUST stop executing callbacks that are registered by the app to receive outputs from the
- [C-0-11] Devices MUST return the following security providers as the first seven array values from the
Security.getProviders()
method, in the given order and with the given names (as returned byProvider.getName()
) and classes, unless the app has modified the list viainsertProviderAt()
orremoveProvider()
. Devices MAY return additional providers after the specified list of providers below.- AndroidNSSP -
android.security.net.config.NetworkSecurityConfigProvider
- AndroidOpenSSL -
com.android.org.conscrypt.OpenSSLProvider
- CertPathProvider -
sun.security.provider.CertPathProvider
- AndroidKeyStoreBCWorkaround -
android.security.keystore.AndroidKeyStoreBCWorkaroundProvider
- BC -
com.android.org.bouncycastle.jce.provider.BouncyCastleProvider
- HarmonyJSSE -
com.android.org.conscrypt.JSSEProvider
- AndroidKeyStore -
android.security.keystore.AndroidKeyStoreProvider
- AndroidNSSP -
The above list is not comprehensive. The Compatibility Test Suite (CTS) tests significant portions of the platform for behavioral compatibility, but not all. It is the responsibility of the implementer to ensure behavioral compatibility with the Android Open Source Project. For this reason, device implementers SHOULD use the source code available via the Android Open Source Project where possible, rather than re-implement significant parts of the system.
3.5.1. Application Restriction
If device implementations implement a proprietary mechanism to restrict apps and that mechanism is more restrictive than the Restricted App Standby Bucket , they:
- [C-1-1] MUST provide user affordance where the user can see the list of restricted apps.
- [C-1-2] MUST provide user affordance to turn on / off the restrictions on each app.
- [C-1-3] MUST not automatically apply restrictions without evidence of poor system health behavior, but MAY apply the restrictions on apps upon detection of poor system health behavior like stuck wakelocks, long running services, and other criteria. The criteria MAY be determined by device implementers but MUST be related to the app's impact on the system health. Other criteria that are not purely related to the system health, such as the app's lack of popularity in the market, MUST NOT be used as criteria.
- [C-1-4] MUST not automatically apply app restrictions for apps when a user has turned off app restrictions manually, and MAY suggest the user to apply app restrictions.
- [C-1-5] MUST inform users if app restrictions are applied to an app automatically. Such information MUST be provided within 24 hours of when the restrictions are applied.
- [C-1-6] MUST return
true
forActivityManager.isBackgroundRestricted()
when the restricted app calls this API. - [C-1-7] MUST NOT restrict the top foreground app that is explicitly used by the user.
- [C-1-8] MUST suspend restrictions on an app that becomes the top foreground application when the user explicitly starts to use the app that used to be restricted.
- [C-1-10] MUST NOT allow an app to be automatically placed in the RESTRICTED bucket within 2 hours of the most recent usage by a user.
If device implementations extend the app restrictions that are implemented in AOSP, they:
- [C-2-1] MUST follow the implementation described in this document .
3.5.2. Application Hibernation
If device implementations include App Hibernation that is included in AOSP or extends the feature that is included in AOSP, then they:
- [C-1-1] MUST meet all the requirements in section 3.5.1 except for [C-1-6] and [C-1-3].
- [C-1-2] MUST only apply the restriction on the app for a user when there is evidence that the user has not used the app for some period of time. This duration is STRONGLY RECOMMENDED to be one month or longer. Usage MUST be defined by either explicit user interaction via the UsageStats#getLastTimeVisible() API or anything that would cause an app to leave the force-stopped state, including service bindings, content provider bindings, explicit broadcasts, etc., which will be tracked by a new API UsageStats#getLastTimeAnyComponentUsed().
- [C-1-3] MUST only apply restrictions affecting all device users when there is evidence that the package has not been used by ANY user for some period of time. This duration is STRONGLY RECOMMENDED to be one month or longer.
- [C-1-4] MUST NOT render the app unable to respond to activity intents, service bindings, content provider requests, or explicit broadcasts.
App Hibernation in AOSP meets the above requirements.
3.6. API Namespaces
Android follows the package and class namespace conventions defined by the Java programming language. To ensure compatibility with third-party applications, device implementers MUST NOT make any prohibited modifications (see below) to these package namespaces:
-
java.*
-
javax.*
-
sun.*
-
android.*
-
androidx.*
-
com.android.*
That is, they:
- [C-0-1] MUST NOT modify the publicly exposed APIs on the Android platform by changing any method or class signatures, or by removing classes or class fields.
- [C-0-2] MUST NOT add any publicly exposed elements (such as classes or interfaces, or fields or methods to existing classes or interfaces) or Test or System APIs to the APIs in the above namespaces. A "publicly exposed element" is any construct that is not decorated with the "@hide" marker as used in the upstream Android source code.
Device implementers MAY modify the underlying implementation of the APIs, but such modifications:
- [C-0-3] MUST NOT impact the stated behavior and Java-language signature of any publicly exposed APIs.
- [C-0-4] MUST NOT be advertised or otherwise exposed to developers.
However, device implementers MAY add custom APIs outside the standard Android namespace, but the custom APIs:
- [C-0-5] MUST NOT be in a namespace owned by or referring to another organization. For instance, device implementers MUST NOT add APIs to the
com.google.*
or similar namespace: only Google may do so. Similarly, Google MUST NOT add APIs to other companies' namespaces. - [C-0-6] MUST be packaged in an Android shared library so that only apps that explicitly use them (via the <uses-library> mechanism) are affected by the increased memory usage of such APIs.
Device implementers MAY add custom APIs in native languages, outside of the NDK APIs, but the custom APIs:
- [C-1-1] MUST NOT be in a NDK library or a library owned by another organization as described here .
If a device implementer proposes to improve one of the package namespaces above (such as by adding useful new functionality to an existing API, or adding a new API), the implementer SHOULD visit source.android.com and begin the process for contributing changes and code, according to the information on that site.
Note that the restrictions above correspond to standard conventions for naming APIs in the Java programming language; this section simply aims to reinforce those conventions and make them binding through inclusion in this Compatibility Definition.
3.7. Runtime Compatibility
Device implementations:
[C-0-1] MUST support the full Dalvik Executable (DEX) format and Dalvik bytecode specification and semantics .
[C-0-2] MUST configure Dalvik runtimes to allocate memory in accordance with the upstream Android platform, and as specified by the following table. (See section 7.1.1 for screen size and screen density definitions.)
SHOULD use Android RunTime (ART), the reference upstream implementation of the Dalvik Executable Format, and the reference implementation's package management system.
SHOULD run fuzz tests under various modes of execution and target architectures to assure the stability of the runtime. Refer to JFuzz and DexFuzz in the Android Open Source Project website.
Note that memory values specified below are considered minimum values and device implementations MAY allocate more memory per application.
Screen Layout | Screen Density | Minimum Application Memory |
---|---|---|
Android Watch | 120 dpi (ldpi) | 32MB |
140 dpi (140dpi) | ||
160 dpi (mdpi) | ||
180 dpi (180dpi) | ||
200 dpi (200dpi) | ||
213 dpi (tvdpi) | ||
220 dpi (220dpi) | 36MB | |
240 dpi (hdpi) | ||
280 dpi (280dpi) | ||
320 dpi (xhdpi) | 48MB | |
360 dpi (360dpi) | ||
400 dpi (400dpi) | 56MB | |
420 dpi (420dpi) | 64MB | |
480 dpi (xxhdpi) | 88MB | |
560 dpi (560dpi) | 112MB | |
640 dpi (xxxhdpi) | 154MB | |
small/normal | 120 dpi (ldpi) | 32MB |
140 dpi (140dpi) | ||
160 dpi (mdpi) | ||
180 dpi (180dpi) | 48MB | |
200 dpi (200dpi) | ||
213 dpi (tvdpi) | ||
220 dpi (220dpi) | ||
240 dpi (hdpi) | ||
280 dpi (280dpi) | ||
320 dpi (xhdpi) | 80MB | |
360 dpi (360dpi) | ||
400 dpi (400dpi) | 96MB | |
420 dpi (420dpi) | 112MB | |
480 dpi (xxhdpi) | 128MB | |
560 dpi (560dpi) | 192MB | |
640 dpi (xxxhdpi) | 256MB | |
بزرگ | 120 dpi (ldpi) | 32MB |
140 dpi (140dpi) | 48MB | |
160 dpi (mdpi) | ||
180 dpi (180dpi) | 80MB | |
200 dpi (200dpi) | ||
213 dpi (tvdpi) | ||
220 dpi (220dpi) | ||
240 dpi (hdpi) | ||
280 dpi (280dpi) | 96MB | |
320 dpi (xhdpi) | 128MB | |
360 dpi (360dpi) | 160 مگابایت | |
400 dpi (400dpi) | 192MB | |
420 dpi (420dpi) | 228MB | |
480 dpi (xxhdpi) | 256MB | |
560 dpi (560dpi) | 384MB | |
640 dpi (xxxhdpi) | 512 مگابایت | |
xlarge | 120 dpi (ldpi) | 48MB |
140 dpi (140dpi) | 80MB | |
160 dpi (mdpi) | ||
180 dpi (180dpi) | 96MB | |
200 dpi (200dpi) | ||
213 dpi (tvdpi) | ||
220 dpi (220dpi) | ||
240 dpi (hdpi) | ||
280 dpi (280dpi) | 144MB | |
320 dpi (xhdpi) | 192MB | |
360 dpi (360dpi) | 240MB | |
400 dpi (400dpi) | 288MB | |
420 dpi (420dpi) | 336MB | |
480 dpi (xxhdpi) | 384MB | |
560 dpi (560dpi) | 576MB | |
640 dpi (xxxhdpi) | 768MB |
3.8. User Interface Compatibility
3.8.1. Launcher (Home Screen)
Android includes a launcher application (home screen) and support for third-party applications to replace the device launcher (home screen).
If device implementations allow third-party applications to replace the device home screen, they:
- [C-1-1] MUST declare the platform feature
android.software.home_screen
. - [C-1-2] MUST return the
AdaptiveIconDrawable
object when the third-party application use<adaptive-icon>
tag to provide their icon, and thePackageManager
methods to retrieve icons are called.
If device implementations include a default launcher that supports in-app pinning of shortcuts, they:
- [C-2-1] MUST report
true
forShortcutManager.isRequestPinShortcutSupported()
. - [C-2-2] MUST have user affordance asking the user before adding a shortcut requested by apps via the
ShortcutManager.requestPinShortcut()
API method. - [C-2-3] MUST support pinned shortcuts and dynamic and static shortcuts as documented on the App Shortcuts page .
Conversely, if device implementations do not support in-app pinning of shortcuts, they:
- [C-3-1] MUST report
false
forShortcutManager.isRequestPinShortcutSupported()
.
If device implementations implement a default launcher that provides quick access to the additional shortcuts provided by third-party apps through the ShortcutManager API, they:
- [C-4-1] MUST support all documented shortcut features (eg static and dynamic shortcuts, pinning shortcuts) and fully implement the APIs of the
ShortcutManager
API class.
If device implementations include a default launcher app that shows badges for the app icons, they:
- [C-5-1] MUST respect the
NotificationChannel.setShowBadge()
API method. In other words, show a visual affordance associated with the app icon if the value is set astrue
, and do not show any app icon badging scheme when all of the app's notification channels have set the value asfalse
. - MAY override the app icon badges with their proprietary badging scheme when third-party applications indicate support of the proprietary badging scheme through the use of proprietary APIs, but SHOULD use the resources and values provided through the notification badges APIs described in the SDK , such as the
Notification.Builder.setNumber()
and theNotification.Builder.setBadgeIconType()
API.
3.8.2. ابزارک ها
Android supports third-party app widgets by defining a component type and corresponding API and lifecycle that allows applications to expose an “AppWidget” to the end user.
If device implementations support third-party app widgets, they:
- [C-1-1] MUST declare support for platform feature
android.software.app_widgets
. - [C-1-2] MUST include built-in support for AppWidgets and expose user interface affordances to add, configure, view, and remove AppWidgets directly within the Launcher.
- [C-1-3] MUST be capable of rendering widgets that are 4 x 4 in the standard grid size. See the App Widget DesignGuidelines in the Android SDK documentation for details.
- MAY support application widgets on the lock screen.
If device implementations support third-party app widgets and in-app pinning of shortcuts, they:
- [C-2-1] MUST report
true
forAppWidgetManager.html.isRequestPinAppWidgetSupported()
. - [C-2-2] MUST have user affordance asking the user before adding a shortcut requested by apps via the
AppWidgetManager.requestPinAppWidget()
API method.
3.8.3. اطلاعیه ها
Android includes Notification
and NotificationManager
APIs that allow third-party app developers to notify users of notable events and attract users' attention using the hardware components (eg sound, vibration and light) and software features (eg notification shade, system bar) of the device .
3.8.3.1. Presentation of Notifications
If device implementations allow third-party apps to notify users of notable events , they:
- [C-1-1] MUST support notifications that use hardware features, as described in the SDK documentation, and to the extent possible with the device implementation hardware. For instance, if a device implementation includes a vibrator, it MUST correctly implement the vibration APIs. If a device implementation lacks hardware, the corresponding APIs MUST be implemented as no-ops. This behavior is further detailed in section 7 .
- [C-1-2] MUST correctly render all resources (icons, animation files, etc.) provided for in the APIs, or in the Status/System Bar icon style guide , although they MAY provide an alternative user experience for notifications than that provided by the reference Android Open Source implementation.
- [C-1-3] MUST honor and implement properly the behaviors described for the APIs to update, remove and group notifications.
- [C-1-4] MUST provide the full behavior of the NotificationChannel API documented in the SDK.
- [C-1-5] MUST provide a user affordance to block and modify a certain third-party app's notification per each channel and app package level.
- [C-1-6] MUST also provide a user affordance to display deleted notification channels.
- [C-1-7] MUST correctly render all resources (images, stickers, icons, etc.) provided through Notification.MessagingStyle alongside the notification text without additional user interaction. For example, MUST show all resources including icons provided through android.app.Person in a group conversation that is set through setGroupConversation .
- [C-SR-1] Are STRONGLY RECOMMENDED to automatically surface a user affordance to block a certain third-party app's notification per each channel and app package level after the user dismisses that notification multiple times.
- [C-SR-2] are STRONGLY RECOMMENDED to provide an affordance for the user to control the notifications that are exposed to apps that have been granted the Notification Listener permission. The granularity MUST be such that the user can control for each such notification listener what notification types are bridged to this listener. The types MUST include "conversations", "alerting", "silent", and "important ongoing" notifications.
- [C-SR-3] are STRONGLY RECOMMENDED to provide an affordance for users to specify apps to exclude from notifying any specific notification listener.
- SHOULD support rich notifications.
- SHOULD present some higher priority notifications as heads-up notifications.
- SHOULD have a user affordance to snooze notifications.
- MAY only manage the visibility and timing of when third-party apps can notify users of notable events to mitigate safety issues such as driver distraction.
Android 11 introduces support for conversation notifications, which are notifications that use MessagingStyle and provides a published People Shortcut ID.
Device implementations:
- [C-SR-4] Are STRONGLY RECOMMENDED to group and display
conversation notifications
ahead of non conversation notifications with the exception of ongoing foreground service notifications andimportance:high
notifications.
If device implementations support conversation notifications
and the app provides the required data for bubbles
, they:
- [C-SR-5] Are STRONGLY RECOMMENDED to display this conversation as a bubble. The AOSP implementation meets these requirements with the default System UI, Settings, and Launcher.
If device implementations support rich notifications, they:
- [C-2-1] MUST use the exact resources as provided through the
Notification.Style
API class and its subclasses for the presented resource elements. - SHOULD present each and every resource element (eg icon, title and summary text) defined in the
Notification.Style
API class and its subclasses.
If device implementations support heads-up notifications: they:
- [C-3-1] MUST use the heads-up notification view and resources as described in the
Notification.Builder
API class when heads-up notifications are presented. - [C-3-2] MUST display the actions provided through
Notification.Builder.addAction()
together with the notification content without additional user interaction as described in the SDK .
3.8.3.2. Notification Listener Service
Android includes the NotificationListenerService
APIs that allow apps (once explicitly enabled by the user) to receive a copy of all notifications as they are posted or updated.
Device implementations:
- [C-0-1] MUST correctly and promptly update notifications in their entirety to all such installed and user-enabled listener services, including any and all metadata attached to the Notification object.
- [C-0-2] MUST respect the
snoozeNotification()
API call, and dismiss the notification and make a callback after the snooze duration that is set in the API call.
If device implementations have a user affordance to snooze notifications, they:
- [C-1-1] MUST reflect the snoozed notification status properly through the standard APIs such as
NotificationListenerService.getSnoozedNotifications()
. - [C-1-2] MUST make this user affordance available to snooze notifications from each installed third-party app's, unless they are from persistent/foreground services.
3.8.3.3. DND (Do not Disturb)
If device implementations support the DND feature, they:
- [C-1-1] MUST, for when the device implementation has provided a means for the user to grant or deny third-party apps to access the DND policy configuration, display Automatic DND rules created by applications alongside the user-created and pre-defined rules.
- [C-1-3] MUST honor the
suppressedVisualEffects
values passed along theNotificationManager.Policy
and if an app has set any of the SUPPRESSED_EFFECT_SCREEN_OFF or SUPPRESSED_EFFECT_SCREEN_ON flags, it SHOULD indicate to the user that the visual effects are suppressed in the DND settings menu.
3.8.4. Assist API's
Android includes the Assist APIs to allow applications to elect how much information of the current context is shared with the assistant on the device.
If device implementations support the Assist action, they:
- [C-2-1] MUST indicate clearly to the end user when the context is shared, by either:
- Each time the assist app accesses the context, displaying a white light around the edges of the screen that meet or exceed the duration and brightness of the Android Open Source Project implementation.
- For the preinstalled assist app, providing a user affordance less than two navigations away from the default voice input and assistant app settings menu , and only sharing the context when the assist app is explicitly invoked by the user through a hotword or assist navigation key input.
- [C-2-2] The designated interaction to launch the assist app as described in section 7.2.3 MUST launch the user-selected assist app, in other words the app that implements
VoiceInteractionService
, or an activity handling theACTION_ASSIST
intent.
3.8.5. Alerts and Toasts
Applications can use the Toast
API to display short non-modal strings to the end user that disappear after a brief period of time, and use the TYPE_APPLICATION_OVERLAY
window type API to display alert windows as an overlay over other apps.
If device implementations include a screen or video output, they:
[C-1-1] MUST provide a user affordance to block an app from displaying alert windows that use the
TYPE_APPLICATION_OVERLAY
. The AOSP implementation meets this requirement by having controls in the notification shade.[C-1-2] MUST honor the Toast API and display Toasts from applications to end users in some highly visible manner.
3.8.6. تم ها
Android provides “themes” as a mechanism for applications to apply styles across an entire Activity or application.
Android includes a “Holo” and "Material" theme family as a set of defined styles for application developers to use if they want to match the Holo theme look and feel as defined by the Android SDK.
If device implementations include a screen or video output, they:
- [C-1-1] MUST NOT alter any of the Holo theme attributes exposed to applications.
- [C-1-2] MUST support the “Material” theme family and MUST NOT alter any of the Material theme attributes or their assets exposed to applications.
- [C-1-3] MUST either set the "sans-serif" font family to Roboto version 2.x for the languages that Roboto supports, or provide a user affordance to change the font used for the "sans-serif" font family to Roboto version 2.x for the languages that Roboto supports.
Android also includes a “Device Default” theme family as a set of defined styles for application developers to use if they want to match the look and feel of the device theme as defined by the device implementer.
- Device implementations MAY modify the Device Default theme attributes exposed to applications.
Android supports a variant theme with translucent system bars, which allows application developers to fill the area behind the status and navigation bar with their app content. To enable a consistent developer experience in this configuration, it is important the status bar icon style is maintained across different device implementations.
If device implementations include a system status bar, they:
- [C-2-1] MUST use white for system status icons (such as signal strength and battery level) and notifications issued by the system, unless the icon is indicating a problematic status or an app requests a light status bar using the WindowInsetsController#APPEARANCE_LIGHT_STATUS_BARS flag.
- [C-2-2] Android device implementations MUST change the color of the system status icons to black (for details, refer to R.style ) when an app requests a light status bar.
3.8.7. Live Wallpapers
Android defines a component type and corresponding API and lifecycle that allows applications to expose one or more “Live Wallpapers” to the end user. Live wallpapers are animations, patterns, or similar images with limited input capabilities that display as a wallpaper, behind other applications.
Hardware is considered capable of reliably running live wallpapers if it can run all live wallpapers, with no limitations on functionality, at a reasonable frame rate with no adverse effects on other applications. If limitations in the hardware cause wallpapers and/or applications to crash, malfunction, consume excessive CPU or battery power, or run at unacceptably low frame rates, the hardware is considered incapable of running live wallpaper. As an example, some live wallpapers may use an OpenGL 2.0 or 3.x context to render their content. Live wallpaper will not run reliably on hardware that does not support multiple OpenGL contexts because the live wallpaper use of an OpenGL context may conflict with other applications that also use an OpenGL context.
- Device implementations capable of running live wallpapers reliably as described above SHOULD implement live wallpapers.
If device implementations implement live wallpapers, they:
- [C-1-1] MUST report the platform feature flag android.software.live_wallpaper.
3.8.8. Activity Switching
The upstream Android source code includes the overview screen , a system-level user interface for task switching and displaying recently accessed activities and tasks using a thumbnail image of the application's graphical state at the moment the user last left the application.
Device implementations including the recents function navigation key as detailed in section 7.2.3 MAY alter the interface.
If device implementations including the recents function navigation key as detailed in section 7.2.3 alter the interface, they:
- [C-1-1] MUST support at least up to 7 displayed activities.
- SHOULD at least display the title of 4 activities at a time.
- [C-1-2] MUST implement the screen pinning behavior and provide the user with a settings menu to toggle the feature.
- SHOULD display highlight color, icon, screen title in recents.
- SHOULD display a closing affordance ("x") but MAY delay this until user interacts with screens.
- SHOULD implement a shortcut to switch easily to the previous activity.
- SHOULD trigger the fast-switch action between the two most recently used apps, when the recents function key is tapped twice.
- SHOULD trigger the split-screen multiwindow-mode, if supported, when the recents functions key is long pressed.
- MAY display affiliated recents as a group that moves together.
- [SR-1] Are STRONGLY RECOMMENDED to use the upstream Android user interface (or a similar thumbnail-based interface) for the overview screen.
3.8.9. Input Management
Android includes support for Input Management and support for third-party input method editors.
If device implementations allow users to use third-party input methods on the device, they:
- [C-1-1] MUST declare the platform feature android.software.input_methods and support IME APIs as defined in the Android SDK documentation.
3.8.10. Lock Screen Media Control
The Remote Control Client API is deprecated from Android 5.0 in favor of the Media Notification Template that allows media applications to integrate with playback controls that are displayed on the lock screen.
3.8.11. Screen savers (previously Dreams)
See section 3.2.3.5 for settings intent to congfigure screen savers.
3.8.12. مکان
If device implementations include a hardware sensor (eg GPS) that is capable of providing the location coordinates, they
- [C-1-2] MUST display the current status of location in the Location menu within Settings.
- [C-1-3] MUST NOT display location modes in the Location menu within Settings.
3.8.13. Unicode and Font
Android includes support for the emoji characters defined in Unicode 10.0 .
If device implementations include a screen or video output, they:
- [C-1-1] MUST be capable of rendering these emoji characters in color glyph.
- [C-1-2] MUST include support for:
- Roboto 2 font with different weights—sans-serif-thin, sans-serif-light, sans-serif-medium, sans-serif-black, sans-serif-condensed, sans-serif-condensed-light for the languages available on the دستگاه
- Full Unicode 7.0 coverage of Latin, Greek, and Cyrillic, including the Latin Extended A, B, C, and D ranges, and all glyphs in the currency symbols block of Unicode 7.0.
- [C-1-3] MUST NOT remove or modify NotoColorEmoji.tff in the system image. (It is acceptable to add a new emoji font to override emoji in NotoColorEmoji.tff)
- SHOULD support the skin tone and diverse family emojis as specified in the Unicode Technical Report #51 .
If device implementations include an IME, they:
- SHOULD provide an input method to the user for these emoji characters.
Android includes support to render Myanmar fonts. Myanmar has several non-Unicode compliant fonts, commonly known as “Zawgyi,” for rendering Myanmar languages.
If device implementations include support for Burmese, they:
- [C-2-1] MUST render text with Unicode compliant font as default; non-Unicode compliant font MUST NOT be set as default font unless the user chooses it in the language picker.
- [C-2-2] MUST support a Unicode font and a non-Unicode compliant font if a non-Unicode compliant font is supported on the device. Non-Unicode compliant font MUST NOT remove or overwrite the Unicode font.
- [C-2-3] MUST render text with non-Unicode compliant font ONLY IF a language code with script code Qaag is specified (eg my-Qaag). No other ISO language or region codes (whether assigned, unassigned, or reserved) can be used to refer to non-Unicode compliant font for Myanmar. App developers and web page authors can specify my-Qaag as the designated language code as they would for any other language.
3.8.14. Multi-windows
If device implementations have the capability to display multiple activities at the same time, they:
- [C-1-1] MUST implement such multi-window mode(s) in accordance with the application behaviors and APIs described in the Android SDK multi-window mode support documentation and meet the following requirements:
- [C-1-2] MUST honor
android:resizeableActivity
that is set by an app in theAndroidManifest.xml
file as described in this SDK . - [C-1-3] MUST NOT offer split-screen or freeform mode if the screen height is less than 440 dp and the screen width is less than 440 dp.
- [C-1-4] An activity MUST NOT be resized to a size smaller than 220dp in multi-window modes other than picture-in-picture.
- Device implementations with screen size
xlarge
SHOULD support freeform mode.
If device implementations support multi-window mode(s), and the split screen mode, they:
- [C-2-2] MUST crop the docked activity of a split-screen multi-window but SHOULD show some content of it, if the Launcher app is the focused window.
- [C-2-3] MUST honor the declared
AndroidManifestLayout_minWidth
andAndroidManifestLayout_minHeight
values of the third-party launcher application and not override these values in the course of showing some content of the docked activity.
If device implementations support multi-window mode(s) and picture-in-picture multi-window mode, they:
[C-3-1] MUST launch activities in picture-in-picture multi-window mode when the app is:
- Targeting API level 26 or higher and declares
android:supportsPictureInPicture
- Targeting API level 25 or lower and declares both
android:resizeableActivity
andandroid:supportsPictureInPicture
.
- Targeting API level 26 or higher and declares
[C-3-2] MUST expose the actions in their SystemUI as specified by the current PIP activity through the
setActions()
API.[C-3-3] MUST support aspect ratios greater than or equal to 1:2.39 and less than or equal to 2.39:1, as specified by the PIP activity through the
setAspectRatio()
API.[C-3-4] MUST use
KeyEvent.KEYCODE_WINDOW
to control the PIP window; if PIP mode is not implemented, the key MUST be available to the foreground activity.[C-3-5] MUST provide a user affordance to block an app from displaying in PIP mode; the AOSP implementation meets this requirement by having controls in the notification shade.
[C-3-6] MUST allocate the following minimum width and height for the PIP window when an application does not declare any value for
AndroidManifestLayout_minWidth
andAndroidManifestLayout_minHeight
:- Devices with the Configuration.uiMode that is set other than
UI_MODE_TYPE_TELEVISION
MUST allocate a minimum width and height of 108 dp. - Devices with the Configuration.uiMode that is set to
UI_MODE_TYPE_TELEVISION
MUST allocate a minimum width of 240 dp and a minimum height of 135 dp.
- Devices with the Configuration.uiMode that is set other than
3.8.15. Display Cutout
Android supports a Display Cutout as described in the SDK document. The DisplayCutout
API defines an area on the edge of the display that may not be functional for an application due to a display cutout or curved display on the edge(s).
If device implementations include display cutout(s), they:
- [C-1-5] MUST NOT have cutout(s) if the device's aspect ratio is 1.0(1:1).
- [C-1-2] MUST NOT have more than one cutout per edge.
- [C-1-3] MUST honor the display cutout flags set by the app through the
WindowManager.LayoutParams
API as described in the SDK. - [C-1-4] MUST report correct values for all cutout metrics defined in the
DisplayCutout
API.
3.8.16. Device Controls
Android includes ControlsProviderService
and Control
APIs to allow third-party applications to publish device controls for quick status and action for users.
See Section 2_2_3 for device-specific requirements.
3.9. Device Administration
Android includes features that allow security-aware applications to perform device administration functions at the system level, such as enforcing password policies or performing remote wipe, through the Android Device Administration API .
If device implementations implement the full range of device administration policies defined in the Android SDK documentation, they:
- [C-1-1] MUST declare
android.software.device_admin
. - [C-1-2] MUST support device owner provisioning as described in section 3.9.1 and section 3.9.1.1 .
3.9.1 Device Provisioning
3.9.1.1 Device owner provisioning
If device implementations declare android.software.device_admin
, they:
- [C-1-1] MUST support enrolling a Device Policy Client (DPC) as a Device Owner app as described below:
- When the device implementation has no user data configured yet, it:
- [C-1-5] MUST enroll the DPC application as the Device Owner app if the device declares Near-Field Communications (NFC) support via the feature flag
android.hardware.nfc
and receives an NFC message containing a record with MIME typeMIME_TYPE_PROVISIONING_NFC
. - [C-1-8] MUST send the ACTION_GET_PROVISIONING_MODE intent after device owner provisioning is triggered so that the DPC app can choose whether to become a Device Owner or a Profile Owner unless it can be determined from context that there is only one valid option (such as for NFC based provisioning where Profile Owner provisioning is not supported).
- [C-1-9] MUST send the ACTION_ADMIN_POLICY_COMPLIANCE intent to the Device Owner app if a Device Owner is established during provisioning regardless of the provisioning method used. The user must not be able to proceed in the Setup Wizard until the Device Owner app finishes.
- [C-1-5] MUST enroll the DPC application as the Device Owner app if the device declares Near-Field Communications (NFC) support via the feature flag
- When the device implementation has user data, it:
- [C-1-7] MUST not enroll any DPC application as the Device Owner App any more.
- When the device implementation has no user data configured yet, it:
- [C-1-2] MUST require some affirmative action before or during the provisioning process to consent to the app being set as Device Owner. Consent can be via user action or by some programmatic means but appropriate disclosure notice (as referenced in AOSP) MUST be shown before device owner provisioning is initiated. Also, the programmatic device owner consent mechanism used (by enterprises) for device owner provisioning MUST NOT interfere with the Out-Of-Box Experience for non-enterprise use.
- [C-1-3] MUST NOT hard code the consent or prevent the use of other device owner apps.
If device implementations declare android.software.device_admin
, but also include a proprietary Device Owner management solution and provide a mechanism to promote an application configured in their solution as a "Device Owner equivalent" to the standard "Device Owner" as recognized by the standard Android DevicePolicyManager APIs, they:
- [C-2-1] MUST have a process in place to verify that the specific app being promoted belongs to a legitimate enterprise device management solution and it has been already configured in the proprietary solution to have the rights equivalent as a "Device Owner" .
- [C-2-2] MUST show the same AOSP Device Owner consent disclosure as the flow initiated by
android.app.action.PROVISION_MANAGED_DEVICE
prior to enrolling the DPC application as "Device Owner". - MAY have user data on the device prior to enrolling the DPC application as "Device Owner".
3.9.1.2 Managed profile provisioning
If device implementations declare android.software.managed_users
, they:
[C-1-1] MUST implement the APIs allowing a Device Policy Controller (DPC) application to become the owner of a new Managed Profile .
[C-1-2] The managed profile provisioning process (the flow initiated by the DPC using the android.app.action.PROVISION_MANAGED_PROFILE ) or by the platform), consent screen and user experience MUST align with the AOSP implementation.
[C-1-3] MUST provide the following user affordances within the Settings to indicate to the user when a particular system function has been disabled by the Device Policy Controller (DPC):
- A consistent icon or other user affordance (for example the upstream AOSP info icon) to represent when a particular setting is restricted by a Device Admin.
- A short explanation message, as provided by the Device Admin via the
setShortSupportMessage
. - The DPC application's icon.
[C-1-4] MUST launch the handler for ACTION_PROVISIONING_SUCCESSFUL intent in the work profile if a Profile Owner is established when provisioning is initiated by the android.app.action.PROVISION_MANAGED_PROFILE intent and the DPC has implemented the handler.
[C-1-5] MUST send ACTION_PROFILE_PROVISIONING_COMPLETE broadcast to the work profile DPC when provisioning is initiated by the android.app.action.PROVISION_MANAGED_PROFILE intent.
[C-1-6] MUST send the ACTION_GET_PROVISIONING_MODE intent after profile owner provisioning is triggered so that the DPC app can choose whether to become a Device Owner or a Profile Owner execpt when provisioning is triggered by the intent android.app.action.PROVISION_MANAGED_PROFILE .
[C-1-7] MUST send the ACTION_ADMIN_POLICY_COMPLIANCE intent to the work profile when a Profile Owner is established during provisioning regardless of which provisioning method is used except when provisioning is triggered by the intent android.app.action.PROVISION_MANAGED_PROFILE . The user must not be able proceed in the Setup Wizard until the Profile Owner app finishes.
[C-1-8] MUST send ACTION_MANAGED_PROFILE_PROVISIONED broadcast to the personal profile DPC when a Profile Owner is established, regardless of the provisioning method used.
3.9.2 Managed Profile Support
If device implementations declare android.software.managed_users
, they:
- [C-1-1] MUST support managed profiles via the
android.app.admin.DevicePolicyManager
APIs. - [C-1-2] MUST allow one and only one managed profile to be created .
- [C-1-3] MUST use an icon badge (similar to the AOSP upstream work badge) to represent the managed applications and widgets and other badged UI elements like Recents & Notifications.
- [C-1-4] MUST display a notification icon (similar to the AOSP upstream work badge) to indicate when user is within a managed profile application.
- [C-1-6] Where a managed profile exists, MUST show a visual affordance in the Intent 'Chooser' to allow the user to forward the intent from the managed profile to the primary user or vice versa, if enabled by the Device Policy کنترل کننده.
- [C-1-7] Where a managed profile exists, MUST expose the following user affordances for both the primary user and the managed profile:
- Separate accounting for battery, location, mobile data and storage usage for the primary user and managed profile.
- Independent management of VPN Applications installed within the primary user or managed profile.
- Independent management of applications installed within the primary user or managed profile.
- Independent management of accounts within the primary user or managed profile.
- [C-1-8] MUST ensure the preinstalled dialer, contacts and messaging applications can search for and look up caller information from the managed profile (if one exists) alongside those from the primary profile, if the Device Policy Controller permits it.
- [C-1-9] MUST ensure that it satisfies all the security requirements applicable for a device with multiple users enabled (see section 9.5 ), even though the managed profile is not counted as another user in addition to the primary user.
If device implementations declare android.software.managed_users
and android.software.secure_lock_screen
, they:
- [C-2-1] MUST support the ability to specify a separate lock screen meeting the following requirements to grant access to apps running in a managed profile only.
- Device implementations MUST honor the
DevicePolicyManager.ACTION_SET_NEW_PASSWORD
intent and show an interface to configure a separate lock screen credential for the managed profile. - The lock screen credentials of the managed profile MUST use the same credential storage and management mechanisms as the parent profile, as documented on the Android Open Source Project Site .
- The DPC password policies MUST apply to only the managed profile's lock screen credentials unless called upon the
DevicePolicyManager
instance returned by getParentProfileInstance .
- Device implementations MUST honor the
- When contacts from the managed profile are displayed in the preinstalled call log, in-call UI, in-progress and missed-call notifications, contacts and messaging apps they SHOULD be badged with the same badge used to indicate managed profile applications.
3.9.3 Managed User Support
If device implementations declare android.software.managed_users
, they:
- [C-1-1] MUST provide a user affordance to logout from the current user and switch back to the primary user in multiple-user session when
isLogoutEnabled
returnstrue
. The user affordance MUST be accessible from the lockscreen without unlocking the device.
If device implementations declare android.software.device_admin
and provide an on-device user affordance to add additional secondary Users , they:
- [C-SR-1] Are STRONGLY RECOMMENDED show the same AOSP Device Owner consent disclosures that were shown in the flow initiated by android.app.action.PROVISION_MANAGED_DEVICE , prior to allowing accounts to be added in the new secondary User, so users understand that the device is managed.
3.10. دسترسی
Android provides an accessibility layer that helps users with disabilities to navigate their devices more easily. In addition, Android provides platform APIs that enable accessibility service implementations to receive callbacks for user and system events and generate alternate feedback mechanisms, such as text-to-speech, haptic feedback, and trackball/d-pad navigation.
If device implementations support third-party accessibility services, they:
- [C-1-1] MUST provide an implementation of the Android accessibility framework as described in the accessibility APIs SDK documentation.
- [C-1-2] MUST generate accessibility events and deliver the appropriate
AccessibilityEvent
to all registeredAccessibilityService
implementations as documented in the SDK. - [C-1-4] MUST provide a user affordance to control accessibility services that declare the AccessibilityServiceInfo.FLAG_REQUEST_ACCESSIBILITY_BUTTON . Note that for device implementations with a system navigation bar, they SHOULD allow the user to have the option for a button in the system's navigation bar to control these services.
If device implementations include preinstalled accessibility services, they:
- [C-2-1] MUST implement these preinstalled accessibility services as Direct Boot Aware apps when the data storage is encrypted with File Based Encryption (FBE).
- SHOULD provide a mechanism in the out-of-box setup flow for users to enable relevant accessibility services, as well as options to adjust the font size, display size and magnification gestures.
3.11. تبدیل متن به گفتار
Android includes APIs that allow applications to make use of text-to-speech (TTS) services and allows service providers to provide implementations of TTS services.
If device implementations reporting the feature android.hardware.audio.output, they:
- [C-1-1] MUST support the Android TTS framework APIs.
If device implementations support installation of third-party TTS engines, they:
- [C-2-1] MUST provide user affordance to allow the user to select a TTS engine for use at system level.
3.12. TV Input Framework
The Android Television Input Framework (TIF) simplifies the delivery of live content to Android Television devices. TIF provides a standard API to create input modules that control Android Television devices.
If device implementations support TIF, they:
- [C-1-1] MUST declare the platform feature
android.software.live_tv
. - [C-1-2] MUST support all TIF APIs such that an application which uses these APIs and the third-party TIF-based inputs service can be installed and used on the device.
3.13. Quick Settings
Android provides a Quick Settings UI component that allows quick access to frequently used or urgently needed actions.
If device implementations include a Quick Settings UI component and support third-party Quick Settings, they:
- [C-1-1] MUST allow the user to add or remove the tiles provided through the
quicksettings
APIs from a third-party app. - [C-1-2] MUST NOT automatically add a tile from a third-party app directly to the Quick Settings.
- [C-1-3] MUST display all the user-added tiles from third-party apps alongside the system-provided quick setting tiles.
3.14. Media UI
If device implementations include non-voice-activated applications (the Apps) that interact with third-party applications through MediaBrowser
or MediaSession
, the Apps:
[C-1-2] MUST clearly display icons obtained via
getIconBitmap()
orgetIconUri()
and titles obtained viagetTitle()
as described inMediaDescription
. May shorten titles to comply with safety regulations (eg driver distraction).[C-1-3] MUST show the third-party application icon whenever displaying content provided by this third-party application.
[C-1-4] MUST allow the user to interact with the entire
MediaBrowser
hierarchy. MAY restrict the access to part of the hierarchy to comply with safety regulations (eg driver distraction), but MUST NOT give preferential treatment based on content or content provider.[C-1-5] MUST consider double tap of
KEYCODE_HEADSETHOOK
orKEYCODE_MEDIA_PLAY_PAUSE
asKEYCODE_MEDIA_NEXT
forMediaSession.Callback#onMediaButtonEvent
.
3.15. برنامه های فوری
If device implementations support Instant Apps, they MUST satisfy the following requirements:
- [C-1-1] Instant Apps MUST only be granted permissions that have the
android:protectionLevel
set to"instant"
. - [C-1-2] Instant Apps MUST NOT interact with installed apps via implicit intents unless one of the following is true:
- The component's intent pattern filter is exposed and has CATEGORY_BROWSABLE
- The action is one of ACTION_SEND, ACTION_SENDTO, ACTION_SEND_MULTIPLE
- The target is explicitly exposed with android:visibleToInstantApps
- [C-1-3] Instant Apps MUST NOT interact explicitly with installed apps unless the component is exposed via android:visibleToInstantApps.
- [C-1-4] Installed Apps MUST NOT see details about Instant Apps on the device unless the Instant App explicitly connects to the installed application.
Device implementations MUST provide the following user affordances for interacting with Instant Apps. The AOSP meets the requirements with the default System UI, Settings, and Launcher. Device implementations:
- [C-1-5] MUST provide a user affordance to view and delete Instant Apps locally cached for each individual app package.
- [C-1-6] MUST provide a persistent user notification that can be collapsed while an Instant App is running in the foreground. This user notification MUST include that Instant Apps do not require installation and provide a user affordance that directs the user to the application info screen in Settings. For Instant Apps launched via web intents, as defined by using an intent with action set to
Intent.ACTION_VIEW
and with a scheme of "http" or "https", an additional user affordance SHOULD allow the user not to launch the Instant App and launch the associated link with the configured web browser, if a browser is available on the device. - [C-1-7] MUST allow running Instant Apps to be accessed from the Recents function if the Recents function is available on the device.
[C-1-8] MUST preload one or more applications or service components with an intent handler for the intents listed in the SDK here and make the intents visible for Instant Apps.
3.16. Companion Device Pairing
Android includes support for companion device pairing to more effectively manage association with companion devices and provides the CompanionDeviceManager
API for apps to access this feature.
If device implementations support the companion device pairing feature, they:
- [C-1-1] MUST declare the feature flag
FEATURE_COMPANION_DEVICE_SETUP
. - [C-1-2] MUST ensure the APIs in the
android.companion
package is fully implemented. - [C-1-3] MUST provide user affordances for the user to select/confirm a companion device is present and operational.
3.17. Heavyweight Apps
If device implementations declare the feature FEATURE_CANT_SAVE_STATE
, then they:
- [C-1-1] MUST have only one installed app that specifies
cantSaveState
running in the system at a time. If the user leaves such an app without explicitly exiting it (for example by pressing home while leaving an active activity the system, instead of pressing back with no remaining active activities in the system), then device implementations MUST prioritize that app in RAM as they do for other things that are expected to remain running, such as foreground services. While such an app is in the background, the system can still apply power management features to it, such as limiting CPU and network access. - [C-1-2] MUST provide a UI affordance to chose the app that won't participate in the normal state save/restore mechanism once the user launches a second app declared with
cantSaveState
attribute. - [C-1-3] MUST NOT apply other changes in policy to apps that specify
cantSaveState
, such as changing CPU performance or changing scheduling prioritization.
If device implementations don't declare the feature FEATURE_CANT_SAVE_STATE
, then they:
- [C-1-1] MUST ignore the
cantSaveState
attribute set by apps and MUST NOT change the app behavior based on that attribute.
3.18. مخاطبین
Android includes Contacts Provider
APIs to allow applications to manage contact information stored on the device. Contact data that is entered directly into the device is typically synchronized with a web service, but the data MAY also only reside locally on the device. Contacts that are only stored on the device are referred to as local contacts.
RawContacts are "associated with" or "stored in" an Account when the ACCOUNT_NAME
, and ACCOUNT_TYPE
, columns for the raw contacts match the corresponding Account.name and Account.type fields of the account.
Default local account : an account for raw contacts that are only stored on the device and not associated with an Account in the AccountManager , which are created with null values for the ACCOUNT_NAME
, and ACCOUNT_TYPE
, columns.
Custom local account : an account for raw contacts that are only stored on the device and not associated with an Account in the AccountManager, which are created with at least one non-null value for the ACCOUNT_NAME
, and ACCOUNT_TYPE
, columns.
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to not create custom local accounts .
If device implementations use a custom local account :
- [C-1-1] The
ACCOUNT_NAME
, of the custom local account MUST be returned byContactsContract.RawContacts.getLocalAccountName
- [C-1-2] The
ACCOUNT_TYPE
, of the custom local account MUST be returned byContactsContract.RawContacts.getLocalAccountType
- [C-1-3] Raw contacts that are inserted by third party applications with the default local account (ie by setting null values for
ACCOUNT_NAME
andACCOUNT_TYPE
) MUST be inserted to the custom local account . - [C-1-4] Raw contacts inserted into the custom local account MUST not be removed when accounts are added or removed.
- [C-1-5] Delete operations performed against the custom local account MUST result in raw contacts being purged immediately (as if the
CALLER_IS_SYNCADAPTER
param was set to true), even if theCALLER\_IS\_SYNCADAPTER
param was set to false or not مشخص شده است.
4. Application Packaging Compatibility
Devices implementations:
- [C-0-1] MUST be capable of installing and running Android “.apk” files as generated by the “aapt” tool included in the official Android SDK .
- As the above requirement may be challenging, device implementations are RECOMMENDED to use the AOSP reference implementation's package management system.
Device implementations:
- [C-0-2] MUST support verifying “.apk” files using the APK Signature Scheme v3 , APK Signature Scheme v2 and JAR signing .
- [C-0-3] MUST NOT extend either the .apk , Android Manifest , Dalvik bytecode , or RenderScript bytecode formats in such a way that would prevent those files from installing and running correctly on other compatible devices.
[C-0-4] MUST NOT allow apps other than the current "installer of record" for the package to silently uninstall the app without any user confirmation, as documented in the SDK for the
DELETE_PACKAGE
permission. The only exceptions are the system package verifier app handling PACKAGE_NEEDS_VERIFICATION intent and the storage manager app handling ACTION_MANAGE_STORAGE intent.[C-0-5] MUST have an activity that handles the
android.settings.MANAGE_UNKNOWN_APP_SOURCES
intent.[C-0-6] MUST NOT install application packages from unknown sources, unless the app that requests the installation meets all the following requirements:
- It MUST declare the
REQUEST_INSTALL_PACKAGES
permission or have theandroid:targetSdkVersion
set at 24 or lower. - It MUST have been granted permission by the user to install apps from unknown sources.
- It MUST declare the
SHOULD provide a user affordance to grant/revoke the permission to install apps from unknown sources per application, but MAY choose to implement this as a no-op and return
RESULT_CANCELED
forstartActivityForResult()
, if the device implementation does not want to allow users to have this choice. However, even in such cases, they SHOULD indicate to the user why there is no such choice presented.[C-0-7] MUST display a warning dialog with the warning string that is provided through the system API
PackageManager.setHarmfulAppWarning
to the user before launching an activity in an application that has been marked by the same system APIPackageManager.setHarmfulAppWarning
as potentially مضرSHOULD provide a user affordance to choose to uninstall or launch an application on the warning dialog.
[C-0-8] MUST implement support for Incremental File System as documented here .
[C-0-9] MUST support verifying .apk files using the APK Signature Scheme v4 .
5. Multimedia Compatibility
Device implementations:
- [C-0-1] MUST support the media formats, encoders, decoders, file types, and container formats defined in section 5.1 for each and every codec declared by
MediaCodecList
. - [C-0-2] MUST declare and report support of the encoders, decoders available to third-party applications via
MediaCodecList
. - [C-0-3] MUST be able to properly decode and make available to third-party apps all the formats it can encode. This includes all bitstreams that its encoders generate and the profiles reported in its
CamcorderProfile
.
Device implementations:
- SHOULD aim for minimum codec latency, in others words, they
- SHOULD NOT consume and store input buffers and return input buffers only once processed.
- SHOULD NOT hold onto decoded buffers for longer than as specified by the standard (eg SPS).
- SHOULD NOT hold onto encoded buffers longer than required by the GOP structure.
All of the codecs listed in the section below are provided as software implementations in the preferred Android implementation from the Android Open Source Project.
Please note that neither Google nor the Open Handset Alliance make any representation that these codecs are free from third-party patents. Those intending to use this source code in hardware or software products are advised that implementations of this code, including in open source software or shareware, may require patent licenses from the relevant patent holders.
5.1. Media Codecs
5.1.1. Audio Encoding
See more details in 5.1.3. Audio Codecs Details .
If device implementations declare android.hardware.microphone
, they MUST support encoding the following audio formats and make them available to third-party apps:
- [C-1-1] PCM/WAVE
- [C-1-2] FLAC
- [C-1-3] Opus
All audio encoders MUST support:
- [C-3-1] PCM 16-bit native byte order audio frames via the
android.media.MediaCodec
API.
5.1.2. Audio Decoding
See more details in 5.1.3. Audio Codecs Details .
If device implementations declare support for the android.hardware.audio.output
feature, they must support decoding the following audio formats:
- [C-1-1] MPEG-4 AAC Profile (AAC LC)
- [C-1-2] MPEG-4 HE AAC Profile (AAC+)
- [C-1-3] MPEG-4 HE AACv2 Profile (enhanced AAC+)
- [C-1-4] AAC ELD (enhanced low delay AAC)
- [C-1-11] xHE-AAC (ISO/IEC 23003-3 Extended HE AAC Profile, which includes the USAC Baseline Profile, and ISO/IEC 23003-4 Dynamic Range Control Profile)
- [C-1-5] FLAC
- [C-1-6] MP3
- [C-1-7] MIDI
- [C-1-8] Vorbis
- [C-1-9] PCM/WAVE including high-resolution audio formats up to 24 bits, 192 kHz sample rate, and 8 channels. Note that this requirement is for decoding only, and that a device is permitted to downsample and downmix during the playback phase.
- [C-1-10] Opus
If device implementations support the decoding of AAC input buffers of multichannel streams (ie more than two channels) to PCM through the default AAC audio decoder in the android.media.MediaCodec
API, the following MUST be supported:
- [C-2-1] Decoding MUST be performed without downmixing (eg a 5.0 AAC stream must be decoded to five channels of PCM, a 5.1 AAC stream must be decoded to six channels of PCM).
- [C-2-2] Dynamic range metadata MUST be as defined in "Dynamic Range Control (DRC)" in ISO/IEC 14496-3, and the
android.media.MediaFormat
DRC keys to configure the dynamic range-related behaviors of the audio decoder. The AAC DRC keys were introduced in API 21, and are:KEY_AAC_DRC_ATTENUATION_FACTOR
,KEY_AAC_DRC_BOOST_FACTOR
,KEY_AAC_DRC_HEAVY_COMPRESSION
,KEY_AAC_DRC_TARGET_REFERENCE_LEVEL
andKEY_AAC_ENCODED_TARGET_LEVEL
. - [SR-1] It is STRONGLY RECOMMENDED that requirements C-2-1 and C-2-2 above are satisfied by all AAC audio decoders.
When decoding USAC audio, MPEG-D (ISO/IEC 23003-4):
- [C-3-1] Loudness and DRC metadata MUST be interpreted and applied according to MPEG-D DRC Dynamic Range Control Profile Level 1.
- [C-3-2] The decoder MUST behave according to the configuration set with the following
android.media.MediaFormat
keys:KEY_AAC_DRC_TARGET_REFERENCE_LEVEL
andKEY_AAC_DRC_EFFECT_TYPE
.
MPEG-4 AAC, HE AAC, and HE AACv2 profile decoders:
- MAY support loudness and dynamic range control using ISO/IEC 23003-4 Dynamic Range Control Profile.
If ISO/IEC 23003-4 is supported and if both ISO/IEC 23003-4 and ISO/IEC 14496-3 metadata are present in a decoded bitstream, then:
- ISO/IEC 23003-4 metadata SHALL take precedence.
All audio decoders MUST support outputting:
- [C-6-1] PCM 16-bit native byte order audio frames via the
android.media.MediaCodec
API.
5.1.3. Audio Codecs Details
Format/Codec | جزئیات | File Types/Container Formats to be supported |
---|---|---|
MPEG-4 AAC Profile (AAC LC) | Support for mono/stereo/5.0/5.1 content with standard sampling rates from 8 to 48 kHz. |
|
MPEG-4 HE AAC Profile (AAC+) | Support for mono/stereo/5.0/5.1 content with standard sampling rates from 16 to 48 kHz. |
|
MPEG-4 HE AACv2 Profile (enhanced AAC+) | Support for mono/stereo/5.0/5.1 content with standard sampling rates from 16 to 48 kHz. |
|
AAC ELD (enhanced low delay AAC) | Support for mono/stereo content with standard sampling rates from 16 to 48 kHz. |
|
USAC | Support for mono/stereo content with standard sampling rates from 7.35 to 48 kHz. | MPEG-4 (.mp4, .m4a) |
AMR-NB | 4.75 to 12.2 kbps sampled @ 8 kHz | 3GPP (.3gp) |
AMR-WB | 9 rates from 6.60 kbit/s to 23.85 kbit/s sampled @ 16 kHz, as defined at AMR-WB, Adaptive Multi-Rate - Wideband Speech Codec | 3GPP (.3gp) |
FLAC | For both encoder and decoder: at least Mono and Stereo modes MUST be supported. Sample rates up to 192 kHz MUST be supported; 16-bit and 24-bit resolution MUST be supported. FLAC 24-bit audio data handling MUST be available with floating point audio configuration. |
|
MP3 | Mono/Stereo 8-320Kbps constant (CBR) or variable bitrate (VBR) |
|
MIDI | MIDI Type 0 and 1. DLS Version 1 and 2. XMF and Mobile XMF. Support for ringtone formats RTTTL/RTX, OTA, and iMelody |
|
وربیس |
| |
PCM/WAVE | PCM codec MUST support 16-bit linear PCM and 16-bit float. WAVE extractor must support 16-bit, 24-bit, 32-bit linear PCM and 32-bit float (rates up to limit of hardware). Sampling rates MUST be supported from 8 kHz to 192 kHz. | WAVE (.wav) |
اپوس | Decoding: Support for mono, stereo, 5.0 and 5.1 content with sampling rates of 8000, 12000, 16000, 24000, and 48000 Hz. Encoding: Support for mono and stereo content with sampling rates of 8000, 12000, 16000, 24000, and 48000 Hz. |
|
5.1.4. Image Encoding
See more details in 5.1.6. Image Codecs Details .
Device implementations MUST support encoding the following image encoding:
- [C-0-1] JPEG
- [C-0-2] PNG
- [C-0-3] WebP
If device implementations support HEIC encoding via android.media.MediaCodec
for media type MIMETYPE_IMAGE_ANDROID_HEIC
, they:
- [C-1-1] MUST provide a hardware-accelerated HEVC encoder codec that supports
BITRATE_MODE_CQ
bitrate control mode,HEVCProfileMainStill
profile and 512 x 512 px frame size.
5.1.5. Image Decoding
See more details in 5.1.6. Image Codecs Details .
Device implementations MUST support decoding the following image encoding:
- [C-0-1] JPEG
- [C-0-2] GIF
- [C-0-3] PNG
- [C-0-4] BMP
- [C-0-5] WebP
- [C-0-6] Raw
If device implementations support HEVC video decoding, they:
- [C-1-1] MUST support HEIF (HEIC) image decoding.
Image decoders that support a high bit-depth format (9+ bits per channel):
- [C-2-1] MUST support outputting an 8-bit equivalent format if requested by the application, for example, via the
ARGB_8888
config ofandroid.graphics.Bitmap
.
5.1.6. Image Codecs Details
Format/Codec | جزئیات | Supported File Types/Container Formats |
---|---|---|
JPEG | Base+progressive | JPEG (.jpg) |
GIF | GIF (.gif) | |
PNG | PNG (.png) | |
BMP | BMP (.bmp) | |
وب پی | WebP (.webp) | |
خام | ARW (.arw), CR2 (.cr2), DNG (.dng), NEF (.nef), NRW (.nrw), ORF (.orf), PEF (.pef), RAF (.raf), RW2 (.rw2), SRW (.srw) | |
HEIF | Image, Image collection, Image sequence | HEIF (.heif), HEIC (.heic) |
Image encoder and decoders exposed through the MediaCodec API
[C-1-1] MUST support YUV420 8:8:8 flexible color format (
COLOR_FormatYUV420Flexible
) throughCodecCapabilities
.[SR-1] STRONGLY RECOMMENDED to support RGB888 color format for input Surface mode.
[C-1-3] MUST support at least one of a planar or semiplanar YUV420 8:8:8 color format:
COLOR_FormatYUV420PackedPlanar
(equivalent toCOLOR_FormatYUV420Planar
) orCOLOR_FormatYUV420PackedSemiPlanar
(equivalent toCOLOR_FormatYUV420SemiPlanar
). They are STRONGLY RECOMMENDED to support both.
5.1.7. Video Codecs
- For acceptable quality of web video streaming and video-conference services, device implementations SHOULD use a hardware VP8 codec that meets the requirements .
If device implementations include a video decoder or encoder:
[C-1-1] Video codecs MUST support output and input bytebuffer sizes that accommodate the largest feasible compressed and uncompressed frame as dictated by the standard and configuration but also not overallocate.
[C-1-2] Video encoders and decoders MUST support YUV420 8:8:8 flexible color formats (
COLOR_FormatYUV420Flexible
) throughCodecCapabilities
.[C-1-3] Video encoders and decoders MUST support at least one of a planar or semiplanar YUV420 8:8:8 color format:
COLOR_FormatYUV420PackedPlanar
(equivalent toCOLOR_FormatYUV420Planar
) orCOLOR_FormatYUV420PackedSemiPlanar
(equivalent toCOLOR_FormatYUV420SemiPlanar
). They are STRONGLY RECOMMENDED to support both.[SR-1] Video encoders and decoders are STRONGLY RECOMMENDED to support at least one of a hardware optimized planar or semiplanar YUV420 8:8:8 color format (YV12, NV12, NV21 or equivalent vendor optimized format.)
[C-1-5] Video decoders that support a high bit-depth format (9+ bits per channel) MUST support outputting an 8-bit equivalent format if requested by the application. This MUST be reflected by supporting an YUV420 8:8:8 color format via
android.media.MediaCodecInfo
.
If device implementations advertise HDR profile support through Display.HdrCapabilities
, they:
- [C-2-1] MUST support HDR static metadata parsing and handling.
If device implementations advertise intra refresh support through FEATURE_IntraRefresh
in the MediaCodecInfo.CodecCapabilities
class, they:
- [C-3-1] MUST support the refresh periods in the range of 10 - 60 frames and accurately operate within 20% of configured refresh period.
Unless the application specifies otherwise using the KEY_COLOR_FORMAT
format key, video decoder implementations:
- [C-4-1] MUST default to the color format optimized for hardware display if configured using Surface output.
- [C-4-2] MUST default to a YUV420 8:8:8 color format optimized for CPU reading if configured to not use Surface output.
5.1.8. Video Codecs List
Format/Codec | جزئیات | File Types/Container Formats to be supported |
---|---|---|
H.263 |
| |
H.264 AVC | See section 5.2 and 5.3 for details |
|
H.265 HEVC | See section 5.3 for details |
|
MPEG-2 | Main Profile |
|
MPEG-4 SP |
| |
VP8 | See section 5.2 and 5.3 for details |
|
VP9 | See section 5.3 for details |
|
5.1.9. Media Codec Security
Device implementations MUST ensure compliance with media codec security features as described below.
Android includes support for OMX, a cross-platform multimedia acceleration API, as well as Codec 2.0, a low-overhead multimedia acceleration API.
If device implementations support multimedia, they:
- [C-1-1] MUST provide support for media codecs either via OMX or Codec 2.0 APIs (or both) as in the Android Open Source Project and not disable or circumvent the security protections. This specifically does not mean that every codec MUST use either the OMX or Codec 2.0 API, only that support for at least one of these APIs MUST be available, and support for the available APIs MUST include the security protections present.
- [C-SR-1] Are STRONGLY RECOMMENDED to include support for Codec 2.0 API.
If device implementations do not support the Codec 2.0 API, they:
- [C-2-1] MUST include the corresponding OMX software codec from the Android Open Source Project (if it is available) for each media format and type (encoder or decoder) supported by the device.
- [C-2-2] Codecs that have names starting with "OMX.google." MUST be based on their Android Open Source Project source code.
- [C-SR-2] Are STRONGLY RECOMMENDED that the OMX software codecs run in a codec process that does not have access to hardware drivers other than memory mappers.
If device implementations support Codec 2.0 API, they:
- [C-3-1] MUST include the corresponding Codec 2.0 software codec from the Android Open Source Project (if it is available) for each media format and type (encoder or decoder) supported by the device.
- [C-3-2] MUST house the Codec 2.0 software codecs in the software codec process as provided in the Android Open Source Project to make it possible to more narrowly grant access to software codecs.
- [C-3-3] Codecs that have names starting with "c2.android." MUST be based on their Android Open Source Project source code.
5.1.10. Media Codec Characterization
If device implementations support media codecs, they:
- [C-1-1] MUST return correct values of media codec characterization via the
MediaCodecInfo
API.
به طور خاص:
- [C-1-2] Codecs with names starting with "OMX." MUST use the OMX APIs and have names that conform to OMX IL naming guidelines.
- [C-1-3] Codecs with names starting with "c2." MUST use the Codec 2.0 API and have names that conform to Codec 2.0 naming guidelines for Android.
- [C-1-4] Codecs with names starting with "OMX.google." or "c2.android." MUST NOT be characterized as vendor or as hardware-accelerated.
- [C-1-5] Codecs that run in a codec process (vendor or system) that have access to hardware drivers other than memory allocators and mappers MUST NOT be characterized as software-only.
- [C-1-6] Codecs not present in the Android Open Source Project or not based on the source code in that project MUST be characterized as vendor.
- [C-1-7] Codecs that utilize hardware acceleration MUST be characterized as hardware accelerated.
- [C-1-8] Codec names MUST NOT be misleading. For example, codecs named "decoders" MUST support decoding, and those named "encoders" MUST support encoding. Codecs with names containing media formats MUST support those formats.
If device implementations support video codecs:
- [C-2-1] All video codecs MUST publish achievable frame rate data for the following sizes if supported by the codec:
SD (low quality) | SD (high quality) | HD 720p | HD 1080p | UHD | |
---|---|---|---|---|---|
وضوح تصویر |
|
|
| 1920 x 1080 px (other than MPEG4) | 3840 x 2160 px (HEVC, VP9) |
- [C-2-2] Video codecs that are characterized as hardware accelerated MUST publish performance points information. They MUST each list all supported standard performance points (listed in
PerformancePoint
API), unless they are covered by another supported standard performance point. - Additionally they SHOULD publish extended performance points if they support sustained video performance other than one of the standard ones listed.
5.2. رمزگذاری ویدیو
If device implementations support any video encoder and make it available to third-party apps, they:
- SHOULD NOT be, over two sliding windows, more than 15% over the bitrate between intraframe (I-frame) intervals.
- SHOULD NOT be more than 100% over the bitrate over a sliding window of 1 second.
If device implementations include an embedded screen display with the diagonal length of at least 2.5 inches or include a video output port or declare the support of a camera via the android.hardware.camera.any
feature flag, they:
- [C-1-1] MUST include the support of at least one of the VP8 or H.264 video encoders, and make it available for third-party applications.
- SHOULD support both VP8 and H.264 video encoders, and make it available for third-party applications.
If device implementations support any of the H.264, VP8, VP9 or HEVC video encoders and make it available to third-party applications, they:
- [C-2-1] MUST support dynamically configurable bitrates.
- SHOULD support variable frame rates, where video encoder SHOULD determine instantaneous frame duration based on the timestamps of input buffers, and allocate its bit bucket based on that frame duration.
If device implementations support the MPEG-4 SP video encoder and make it available to third-party apps, they:
- SHOULD support dynamically configurable bitrates for the supported encoder.
If device implementations provide hardware accelerated video or image encoders, and support one or more attached or pluggable hardware camera(s) exposed through the android.camera
APIs:
- [C-4-1] all hardware accelerated video and image encoders MUST support encoding frames from the hardware camera(s).
- SHOULD support encoding frames from the hardware camera(s) through all video or image encoders.
If device implementations provide HDR encoding, they:
- [C-SR-1] are STRONGLY RECOMMENDED to provide a plugin for the seamless transcoding API to convert from HDR format to SDR format.
5.2.1. H.263
If device implementations support H.263 encoders and make it available to third-party apps, they:
- [C-1-1] MUST support Baseline Profile Level 45.
- SHOULD support dynamically configurable bitrates for the supported encoder.
5.2.2. H.264
If device implementations support H.264 codec, they:
- [C-1-1] MUST support Baseline Profile Level 3. However, support for ASO (Arbitrary Slice Ordering), FMO (Flexible Macroblock Ordering) and RS (Redundant Slices) is OPTIONAL. Moreover, to maintain compatibility with other Android devices, it is RECOMMENDED that ASO, FMO and RS are not used for Baseline Profile by encoders.
- [C-1-2] MUST support the SD (Standard Definition) video encoding profiles in the following table.
- SHOULD support Main Profile Level 4.
- SHOULD support the HD (High Definition) video encoding profiles as indicated in the following table.
If device implementations report support of H.264 encoding for 720p or 1080p resolution videos through the media APIs, they:
- [C-2-1] MUST support the encoding profiles in the following table.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | |
---|---|---|---|---|
وضوح تصویر | 320 x 240 px | 720 x 480 px | 1280 x 720 px | 1920 x 1080 px |
Video frame rate | 20 فریم بر ثانیه | 30 fps | 30 fps | 30 fps |
Video bitrate | 384 Kbps | 2 Mbps | 4 Mbps | 10 Mbps |
5.2.3. VP8
If device implementations support VP8 codec, they:
- [C-1-1] MUST support the SD video encoding profiles.
- SHOULD support the following HD (High Definition) video encoding profiles.
- [C-1-2] MUST support writing Matroska WebM files.
- SHOULD provide a hardware VP8 codec that meets the WebM project RTC hardware coding requirements , to ensure acceptable quality of web video streaming and video-conference services.
If device implementations report support of VP8 encoding for 720p or 1080p resolution videos through the media APIs, they:
- [C-2-1] MUST support the encoding profiles in the following table.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | |
---|---|---|---|---|
وضوح تصویر | 320 x 180 px | 640 x 360 px | 1280 x 720 px | 1920 x 1080 px |
Video frame rate | 30 fps | 30 fps | 30 fps | 30 fps |
Video bitrate | 800 Kbps | 2 Mbps | 4 Mbps | 10 Mbps |
5.2.4. VP9
If device implementations support VP9 codec, they:
- [C-1-2] MUST support Profile 0 Level 3.
- [C-1-1] MUST support writing Matroska WebM files.
- [C-1-3] MUST generate CodecPrivate data.
- SHOULD support the HD decoding profiles as indicated in the following table.
- [C-SR-1] are STRONGLY RECOMMENDED to support the HD decoding profiles as indicated in the following table if there is a hardware encoder.
SD | HD 720p | HD 1080p | UHD | |
---|---|---|---|---|
وضوح تصویر | 720 x 480 px | 1280 x 720 px | 1920 x 1080 px | 3840 x 2160 px |
Video frame rate | 30 fps | 30 fps | 30 fps | 30 fps |
Video bitrate | 1.6 Mbps | 4 Mbps | 5 Mbps | 20 Mbps |
If device implementations claim to support Profile 2 or Profile 3 through the Media APIs:
- Support for 12-bit format is OPTIONAL.
5.2.5. H.265
If device implementations support H.265 codec, they:
- [C-1-1] MUST support Main Profile Level 3.
- SHOULD support the HD encoding profiles as indicated in the following table.
- [C-SR-1] are STRONGLY RECOMMENDED to support the HD encoding profiles as indicated in the following table if there is a hardware encoder.
SD | HD 720p | HD 1080p | UHD | |
---|---|---|---|---|
وضوح تصویر | 720 x 480 px | 1280 x 720 px | 1920 x 1080 px | 3840 x 2160 px |
Video frame rate | 30 fps | 30 fps | 30 fps | 30 fps |
Video bitrate | 1.6 Mbps | 4 Mbps | 5 Mbps | 20 Mbps |
5.3. Video Decoding
If device implementations support VP8, VP9, H.264, or H.265 codecs, they:
- [C-1-1] MUST support dynamic video resolution and frame rate switching through the standard Android APIs within the same stream for all VP8, VP9, H.264, and H.265 codecs in real time and up to the maximum resolution supported by each codec on the device.
5.3.1. MPEG-2
If device implementations support MPEG-2 decoders, they:
- [C-1-1] MUST support the Main Profile High Level.
5.3.2. H.263
If device implementations support H.263 decoders, they:
- [C-1-1] MUST support Baseline Profile Level 30 and Level 45.
5.3.3. MPEG-4
If device implementations with MPEG-4 decoders, they:
- [C-1-1] MUST support Simple Profile Level 3.
5.3.4. H.264
If device implementations support H.264 decoders, they:
- [C-1-1] MUST support Main Profile Level 3.1 and Baseline Profile. Support for ASO (Arbitrary Slice Ordering), FMO (Flexible Macroblock Ordering) and RS (Redundant Slices) is OPTIONAL.
- [C-1-2] MUST be capable of decoding videos with the SD (Standard Definition) profiles listed in the following table and encoded with the Baseline Profile and Main Profile Level 3.1 (including 720p30).
- SHOULD be capable of decoding videos with the HD (High Definition) profiles as indicated in the following table.
If the height that is reported by the Display.getSupportedModes()
method is equal or greater than the video resolution, device implementations:
- [C-2-1] MUST support the HD 720p video decoding profiles in the following table.
- [C-2-2] MUST support the HD 1080p video decoding profiles in the following table.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | |
---|---|---|---|---|
وضوح تصویر | 320 x 240 px | 720 x 480 px | 1280 x 720 px | 1920 x 1080 px |
Video frame rate | 30 fps | 30 fps | 60 فریم بر ثانیه | 30 fps (60 fps Television ) |
Video bitrate | 800 Kbps | 2 Mbps | 8 Mbps | 20 Mbps |
5.3.5. H.265 (HEVC)
If device implementations support H.265 codec, they:
- [C-1-1] MUST support the Main Profile Level 3 Main tier and the SD video decoding profiles as indicated in the following table.
- SHOULD support the HD decoding profiles as indicated in the following table.
- [C-1-2] MUST support the HD decoding profiles as indicated in the following table if there is a hardware decoder.
If the height that is reported by the Display.getSupportedModes()
method is equal to or greater than the video resolution, then:
- [C-2-1] Device implementations MUST support at least one of H.265 or VP9 decoding of 720, 1080 and UHD profiles.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | UHD | |
---|---|---|---|---|---|
وضوح تصویر | 352 x 288 px | 720 x 480 px | 1280 x 720 px | 1920 x 1080 px | 3840 x 2160 px |
Video frame rate | 30 fps | 30 fps | 30 fps | 30/60 fps (60 fps Television with H.265 hardware decoding ) | 60 فریم بر ثانیه |
Video bitrate | 600 Kbps | 1.6 Mbps | 4 Mbps | 5 Mbps | 20 Mbps |
If device implementations claim to support an HDR Profile through the Media APIs:
- [C-3-1] Device implementations MUST accept the required HDR metadata from the application, as well as support extracting and outputting the required HDR metadata from the bitstream and/or container.
- [C-3-2] Device implementations MUST properly display HDR content on the device screen or on a standard video output port (eg, HDMI).
5.3.6. VP8
If device implementations support VP8 codec, they:
- [C-1-1] MUST support the SD decoding profiles in the following table.
- SHOULD use a hardware VP8 codec that meets the requirements .
- SHOULD support the HD decoding profiles in the following table.
If the height as reported by the Display.getSupportedModes()
method is equal or greater than the video resolution, then:
- [C-2-1] Device implementations MUST support 720p profiles in the following table.
- [C-2-2] Device implementations MUST support 1080p profiles in the following table.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | |
---|---|---|---|---|
وضوح تصویر | 320 x 180 px | 640 x 360 px | 1280 x 720 px | 1920 x 1080 px |
Video frame rate | 30 fps | 30 fps | 30 fps (60 fps Television ) | 30 (60 fps Television ) |
Video bitrate | 800 Kbps | 2 Mbps | 8 Mbps | 20 Mbps |
5.3.7. VP9
If device implementations support VP9 codec, they:
- [C-1-1] MUST support the SD video decoding profiles as indicated in the following table.
- SHOULD support the HD decoding profiles as indicated in the following table.
If device implementations support VP9 codec and a hardware decoder:
- [C-2-1] MUST support the HD decoding profiles as indicated in the following table.
If the height that is reported by the Display.getSupportedModes()
method is equal to or greater than the video resolution, then:
- [C-3-1] Device implementations MUST support at least one of VP9 or H.265 decoding of the 720, 1080 and UHD profiles.
SD (Low quality) | SD (High quality) | HD 720p | HD 1080p | UHD | |
---|---|---|---|---|---|
وضوح تصویر | 320 x 180 px | 640 x 360 px | 1280 x 720 px | 1920 x 1080 px | 3840 x 2160 px |
Video frame rate | 30 fps | 30 fps | 30 fps | 30 fps (60 fps Television with VP9 hardware decoding ) | 60 فریم بر ثانیه |
Video bitrate | 600 Kbps | 1.6 Mbps | 4 Mbps | 5 Mbps | 20 Mbps |
If device implementations claim to support VP9Profile2
or VP9Profile3
through the 'CodecProfileLevel' media APIs:
- Support for 12-bit format is OPTIONAL.
If device implementations claim to support an HDR Profile ( VP9Profile2HDR
, VP9Profile2HDR10Plus
, VP9Profile3HDR
, VP9Profile3HDR10Plus
) through the media APIs:
- [C-4-1] Device implementations MUST accept the required HDR metadata (
KEY_HDR_STATIC_INFO
for all HDR profiles, as well as 'KEY_HDR10_PLUS_INFO' for HDR10Plus profiles) from the application. They also MUST support extracting and outputting the required HDR metadata from the bitstream and/or container. - [C-4-2] Device implementations MUST properly display HDR content on the device screen or on a standard video output port (eg, HDMI).
5.3.8. دالبی ویژن
If device implementations declare support for the Dolby Vision decoder through HDR_TYPE_DOLBY_VISION
, they:
- [C-1-1] MUST provide a Dolby Vision-capable extractor.
- [C-1-2] MUST properly display Dolby Vision content on the device screen or on a standard video output port (eg, HDMI).
- [C-1-3] MUST set the track index of backward-compatible base-layer(s) (if present) to be the same as the combined Dolby Vision layer's track index.
5.3.9. AV1
If device implementations support AV1 codec, they:
- [C-1-1] MUST support Profile 0 including 10-bit content.
5.4. ضبط صدا
While some of the requirements outlined in this section are listed as SHOULD since Android 4.3, the Compatibility Definition for future versions are planned to change these to MUST. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements that are listed as SHOULD, or they will not be able to attain Android compatibility when upgraded to the future version.
5.4.1. Raw Audio Capture and Microphone Information
If device implementations declare android.hardware.microphone
, they:
[C-1-1] MUST allow capture of raw audio content with the following characteristics:
- Format : Linear PCM, 16-bit
- Sampling rates : 8000, 11025, 16000, 44100, 48000 Hz
- Channels : Mono
SHOULD allow capture of raw audio content with the following characteristics:
- Format : Linear PCM, 16-bit and 24-bit
- Sampling rates : 8000, 11025, 16000, 22050, 24000, 32000, 44100, 48000 Hz
- Channels : As many channels as the number of microphones on the device
[C-1-2] MUST capture at above sample rates without up-sampling.
[C-1-3] MUST include an appropriate anti-aliasing filter when the sample rates given above are captured with down-sampling.
SHOULD allow AM radio and DVD quality capture of raw audio content, which means the following characteristics:
- Format : Linear PCM, 16-bit
- Sampling rates : 22050, 48000 Hz
- Channels : Stereo
[C-1-4] MUST honor the
MicrophoneInfo
API and properly fill in information for the available microphones on device accessible to the third-party applications via theAudioManager.getMicrophones()
API, and the currently active microphones which are accessible to the third party applications via theAudioRecord.getActiveMicrophones()
andMediaRecorder.getActiveMicrophones()
APIs. If device implementations allow AM radio and DVD quality capture of raw audio content, they:[C-2-1] MUST capture without up-sampling at any ratio higher than 16000:22050 or 44100:48000.
[C-2-2] MUST include an appropriate anti-aliasing filter for any up-sampling or down-sampling.
5.4.2. Capture for Voice Recognition
If device implementations declare android.hardware.microphone
, they:
- [C-1-1] MUST capture
android.media.MediaRecorder.AudioSource.VOICE_RECOGNITION
audio source at one of the sampling rates, 44100 and 48000. - [C-1-2] MUST, by default, disable any noise reduction audio processing when recording an audio stream from the
AudioSource.VOICE_RECOGNITION
audio source. - [C-1-3] MUST, by default, disable any automatic gain control when recording an audio stream from the
AudioSource.VOICE_RECOGNITION
audio source. - SHOULD record the voice recognition audio stream with approximately flat amplitude versus frequency characteristics: specifically, ±3 dB, from 100 Hz to 4000 Hz.
- SHOULD record the voice recognition audio stream with input sensitivity set such that a 90 dB sound power level (SPL) source at 1000 Hz yields RMS of 2500 for 16-bit samples.
- SHOULD record the voice recognition audio stream so that the PCM amplitude levels linearly track input SPL changes over at least a 30 dB range from -18 dB to +12 dB re 90 dB SPL at the microphone.
- SHOULD record the voice recognition audio stream with total harmonic distortion (THD) less than 1% for 1 kHz at 90 dB SPL input level at the microphone.
If device implementations declare android.hardware.microphone
and noise suppression (reduction) technologies tuned for speech recognition, they:
- [C-2-1] MUST allow this audio effect to be controllable with the
android.media.audiofx.NoiseSuppressor
API. - [C-2-2] MUST uniquely identify each noise suppression technology implementation via the
AudioEffect.Descriptor.uuid
field.
5.4.3. Capture for Rerouting of Playback
The android.media.MediaRecorder.AudioSource
class includes the REMOTE_SUBMIX
audio source.
If device implementations declare both android.hardware.audio.output
and android.hardware.microphone
, they:
[C-1-1] MUST properly implement the
REMOTE_SUBMIX
audio source so that when an application uses theandroid.media.AudioRecord
API to record from this audio source, it captures a mix of all audio streams except for the following:-
AudioManager.STREAM_RING
-
AudioManager.STREAM_ALARM
-
AudioManager.STREAM_NOTIFICATION
-
5.4.4. Acoustic Echo Canceler
If device implementations declare android.hardware.microphone
, they:
- SHOULD implement an Acoustic Echo Canceler (AEC) technology tuned for voice communication and applied to the capture path when capturing using
AudioSource.VOICE_COMMUNICATION
If device implementations provides an Acoustic Echo Canceler which is inserted in the capture audio path when AudioSource.VOICE_COMMUNICATION
is selected, they:
- [C-SR-1] are STRONGLY_RECOMMENDED to declare this via AcousticEchoCanceler API method AcousticEchoCanceler.isAvailable()
- [C-SR-2] are STRONGLY_RECOMMENDED to allow this audio effect to be controllable with the AcousticEchoCanceler API.
- [C-SR-3] are STRONGLY_RECOMMENDED to uniquely identify each AEC technology implementation via the AudioEffect.Descriptor.uuid field.
5.4.5. Concurrent Capture
If device implementations declare android.hardware.microphone
,they MUST implement concurrent capture as described in this document . به طور مشخص:
- [C-1-1] MUST allow concurrent access to microphone by an accessibility service capturing with
AudioSource.VOICE_RECOGNITION
and at least one application capturing with anyAudioSource
. - [C-1-2] MUST allow concurrent access to microphone by a pre-installed application that holds an Assistant role and at least one application capturing with any
AudioSource
except forAudioSource.VOICE_COMMUNICATION
orAudioSource.CAMCORDER
. - [C-1-3] MUST silence the audio capture for any other application, except for an accessibility service, while an application is capturing with
AudioSource.VOICE_COMMUNICATION
orAudioSource.CAMCORDER
. However, when an app is capturing viaAudioSource.VOICE_COMMUNICATION
then another app can capture the voice call if it is a privileged (pre-installed) app with permissionCAPTURE_AUDIO_OUTPUT
. - [C-1-4] If two or more applications are capturing concurrently and if neither app has an UI on top, the one that started capture the most recently receives audio.
5.4.6. Microphone Gain Levels
If device implementations declare android.hardware.microphone
, they:
- SHOULD exhibit approximately flat amplitude-versus-frequency characteristics in the mid-frequency range: specifically ±3dB from 100 Hz to 4000 Hz for each and every microphone used to record the voice recognition audio source.
- SHOULD set audio input sensitivity such that a 1000 Hz sinusoidal tone source played at 90 dB Sound Pressure Level (SPL) yields a response with RMS of 2500 for 16 bit-samples (or -22.35 dB Full Scale for floating point/double precision samples) for each and every microphone used to record the voice recognition audio source.
- [C-SR-1] are STRONGLY RECOMMENDED to exhibit amplitude levels in the low frequency range: specifically from ±20 dB from 5 Hz to 100 Hz compared to the mid-frequency range for each and every microphone used to record the voice recognition audio منبع
- [C-SR-2] are STRONGLY RECOMMENDED to exhibit amplitude levels in the high frequency range: specifically from ±30 dB from 4000 Hz to 22 KHz compared to the mid-frequency range for each and every microphone used to record the voice recognition audio منبع
5.5. Audio Playback
Android includes the support to allow apps to playback audio through the audio output peripheral as defined in section 7.8.2.
5.5.1. Raw Audio Playback
If device implementations declare android.hardware.audio.output
, they:
[C-1-1] MUST allow playback of raw audio content with the following characteristics:
- Source formats : Linear PCM, 16-bit, 8-bit, float
- Channels : Mono, Stereo, valid multichannel configurations with up to 8 channels
- Sampling rates (in Hz) :
- 8000, 11025, 16000, 22050, 24000, 32000, 44100, 48000 at the channel configurations listed above
- 96000 in mono and stereo
5.5.2. جلوه های صوتی
Android provides an API for audio effects for device implementations.
If device implementations declare the feature android.hardware.audio.output
, they:
- [C-1-1] MUST support the
EFFECT_TYPE_EQUALIZER
andEFFECT_TYPE_LOUDNESS_ENHANCER
implementations controllable through the AudioEffect subclassesEqualizer
andLoudnessEnhancer
. - [C-1-2] MUST support the visualizer API implementation, controllable through the
Visualizer
class. - [C-1-3] MUST support the
EFFECT_TYPE_DYNAMICS_PROCESSING
implementation controllable through the AudioEffect subclassDynamicsProcessing
. - SHOULD support the
EFFECT_TYPE_BASS_BOOST
,EFFECT_TYPE_ENV_REVERB
,EFFECT_TYPE_PRESET_REVERB
, andEFFECT_TYPE_VIRTUALIZER
implementations controllable through theAudioEffect
sub-classesBassBoost
,EnvironmentalReverb
,PresetReverb
, andVirtualizer
. - [C-SR-1] Are STRONGLY RECOMMENDED to support effects in floating-point and multichannel.
5.5.3. Audio Output Volume
Automotive device implementations:
- SHOULD allow adjusting audio volume separately per each audio stream using the content type or usage as defined by AudioAttributes and car audio usage as publicly defined in
android.car.CarAudioManager
.
5.5.4. Audio Offload
If device implementations support audio offload playback , they:
- [C-SR-1] Are STRONGLY RECOMMENDED to trim the played gapless audio content when specified by the AudioTrack gapless API and the media container for MediaPlayer.
5.6. Audio Latency
Audio latency is the time delay as an audio signal passes through a system. Many classes of applications rely on short latencies, to achieve real-time sound effects.
For the purposes of this section, use the following definitions:
- output latency . The interval between when an application writes a frame of PCM-coded data and when the corresponding sound is presented to environment at an on-device transducer or signal leaves the device via a port and can be observed externally.
- cold output latency . The time between starting an output stream and the presentation time of the first frame based on timestamps, when the audio output system has been idle and powered down prior to the request.
- continuous output latency . The output latency for subsequent frames, after the device is playing audio.
- input latency . The interval between when a sound is presented by environment to device at an on-device transducer or signal enters the device via a port and when an application reads the corresponding frame of PCM-coded data.
- lost input . The initial portion of an input signal that is unusable or unavailable.
- cold input latency . The time between starting the stream and when the first valid frame is received, when the audio input system has been idle and powered down prior to the request.
- continuous input latency . The input latency for subsequent frames, while the device is capturing audio.
- cold output jitter . The variability among separate measurements of cold output latency values.
- cold input jitter . The variability among separate measurements of cold input latency values.
- continuous round-trip latency . The sum of continuous input latency plus continuous output latency plus one buffer period. The buffer period allows time for the app to process the signal and time for the app to mitigate phase difference between input and output streams.
- OpenSL ES PCM buffer queue API . The set of PCM-related OpenSL ES APIs within Android NDK .
- AAudio native audio API . The set of AAudio APIs within Android NDK .
- Timestamp . A pair consisting of a relative frame position within a stream and the estimated time when that frame enters or leaves the audio processing pipeline on the associated endpoint. See also AudioTimestamp .
- glitch . A temporary interruption or incorrect sample value in the audio signal, typically caused by a buffer underrun for output, buffer overrun for input, or any other source of digital or analog noise.
- mean absolute deviation . The average of the absolute value of the deviations from the mean for a set of values.
- tap-to-tone latency . The time between when the screen is tapped and when a tone generated as a result of that tap is heard on the speaker.
If device implementations declare android.hardware.audio.output
, they MUST meet or exceed the following requirements:
- [C-1-1] The output timestamp returned by AudioTrack.getTimestamp and
AAudioStream_getTimestamp
is accurate to +/- 2 ms. - [C-1-2] Cold output latency of 500 milliseconds or less.
If device implementations declare android.hardware.audio.output
they are STRONGLY RECOMMENDED to meet or exceed the following requirements:
- [C-SR-1] Cold output latency of 100 milliseconds or less over the speaker data path. Existing and new devices that run this version of Android are VERY STRONGLY RECOMMENDED to meet these requirements now. In a future platform release, we will require Cold output latency of 200 ms or less as a MUST.
- [C-SR-2] Tap-to-tone latency of 80 milliseconds or less.
- [C-SR-3] Minimize the cold output jitter.
- [C-SR-4] The output timestamp returned by AudioTrack.getTimestamp and
AAudioStream_getTimestamp
is accurate to +/- 1 ms.
If device implementations meet the above requirements, after any initial calibration, when using the AAudio native audio API, for continuous output latency and cold output latency over at least one supported audio output device, they are:
- [C-SR-5] STRONGLY RECOMMENDED to report low-latency audio by declaring
android.hardware.audio.low_latency
feature flag. - [C-SR-6] STRONGLY RECOMMENDED to meet the requirements for low-latency audio via the AAudio API.
- [C-SR-7] STRONGLY RECOMMENDED to ensure that for streams that return
AAUDIO_PERFORMANCE_MODE_LOW_LATENCY
fromAAudioStream_getPerformanceMode()
, the value returned byAAudioStream_getFramesPerBurst()
is less than or equal to the value returned byandroid.media.AudioManager.getProperty(String)
for property keyAudioManager.PROPERTY_OUTPUT_FRAMES_PER_BUFFER
.
If device implementations do not meet the requirements for low-latency audio via the AAudio native audio API, they:
- [C-2-1] MUST NOT report support for low-latency audio.
If device implementations include android.hardware.microphone
, they MUST meet these input audio requirements:
- [C-3-1] Limit the error in input timestamps, as returned by AudioRecord.getTimestamp or
AAudioStream_getTimestamp
, to +/- 2 ms. "Error" here means the deviation from the correct value. - [C-3-2] Cold input latency of 500 milliseconds or less.
If device implementations include android.hardware.microphone
, they are STRONGLY RECOMMENDED to meet these input audio requirements:
- [C-SR-8] Cold input latency of 100 milliseconds or less over the microphone data path. Existing and new devices that run this version of Android are VERY STRONGLY RECOMMENDED to meet these requirements now. In a future platform release we will require Cold input latency of 200 ms or less as a MUST.
- [C-SR-9] Continuous input latency of 30 milliseconds or less.
- [C-SR-10] Minimize the cold input jitter.
- [C-SR-11] Limit the error in input timestamps, as returned by AudioRecord.getTimestamp or
AAudioStream_getTimestamp
, to +/- 1 ms.
If device implementations declare android.hardware.audio.output
and android.hardware.microphone
, they:
- [C-SR-12] Are STRONGLY RECOMMENDED to have a Mean Continuous Round-Trip Latency of 50 milliseconds or less over 5 measurements, with a Mean Absolute Deviation less than 10 msec, over at least one supported path.
5.7. پروتکل های شبکه
Device implementations MUST support the media network protocols for audio and video playback as specified in the Android SDK documentation.
For each codec and container format that a device implementation is required to support, the device implementation:
[C-1-1] MUST support that codec or container over HTTP and HTTPS.
[C-1-2] MUST support the corresponding media segment formats as shown in the media segment formats table below over HTTP Live Streaming draft protocol, Version 7 .
[C-1-3] MUST support the corresponding RTSP payload formats as shown in the RTSP table below. For exceptions please see the table footnotes in section 5.1 .
Media Segment Formats
Segment formats | مرجع(های) | Required codec support |
---|---|---|
MPEG-2 Transport Stream | ISO 13818 | Video codecs:
and MPEG-2. Audio codecs:
|
AAC with ADTS framing and ID3 tags | ISO 13818-7 | See section 5.1.1 for details on AAC and its variants |
WebVTT | WebVTT |
RTSP (RTP, SDP)
نام پروفایل | مرجع(های) | Required codec support |
---|---|---|
H264 AVC | RFC 6184 | See section 5.1.8 for details on H264 AVC |
MP4A-LATM | RFC 6416 | See section 5.1.3 for details on AAC and its variants |
H263-1998 | RFC 3551 RFC 4629 RFC 2190 | See section 5.1.8 for details on H263 |
H263-2000 | RFC 4629 | See section 5.1.8 for details on H263 |
AMR | RFC 4867 | See section 5.1.3 for details on AMR-NB |
AMR-WB | RFC 4867 | See section 5.1.3 for details on AMR-WB |
MP4V-ES | RFC 6416 | See section 5.1.8 for details on MPEG-4 SP |
mpeg4-generic | RFC 3640 | See section 5.1.3 for details on AAC and its variants |
MP2T | RFC 2250 | See MPEG-2 Transport Stream underneath HTTP Live Streaming for details |
5.8. Secure Media
If device implementations support secure video output and are capable of supporting secure surfaces, they:
- [C-1-1] MUST declare support for
Display.FLAG_SECURE
.
If device implementations declare support for Display.FLAG_SECURE
and support wireless display protocol, they:
- [C-2-1] MUST secure the link with a cryptographically strong mechanism such as HDCP 2.x or higher for the displays connected through wireless protocols such as Miracast.
If device implementations declare support for Display.FLAG_SECURE
and support wired external display, they:
- [C-3-1] MUST support HDCP 1.2 or higher for all external displays connected via a user-accessible wired port.
5.9. Musical Instrument Digital Interface (MIDI)
If device implementations report support for feature android.software.midi
via the android.content.pm.PackageManager
class, they:
[C-1-1] MUST support MIDI over all MIDI-capable hardware transports for which they provide generic non-MIDI connectivity, where such transports are:
- USB host mode, section 7.7
- MIDI over Bluetooth LE acting in central role, section 7.4.3
[C-1-2] MUST support the inter-app MIDI software transport (virtual MIDI devices)
[C-1-3] MUST include libamidi.so (native MIDI support)
SHOULD support MIDI over USB peripheral mode, section 7.7
5.10. Professional Audio
If device implementations report support for feature android.hardware.audio.pro
via the android.content.pm.PackageManager class, they:
- [C-1-1] MUST report support for feature
android.hardware.audio.low_latency
. - [C-1-2] MUST have the continuous round-trip audio latency, as defined in section 5.6 Audio Latency , MUST be 20 milliseconds or less and SHOULD be 10 milliseconds or less over at least one supported path.
- [C-1-3] MUST include a USB port(s) supporting USB host mode and USB peripheral mode.
- [C-1-4] MUST report support for feature
android.software.midi
. - [C-1-5] MUST meet latencies and USB audio requirements using the AAudio native audio API.
- [C-1-6] MUST have Cold output latency of 200 milliseconds or less.
- [C-1-7] MUST have Cold input latency of 200 milliseconds or less.
- [C-SR-1] Are STRONGLY RECOMMENDED to meet latencies as defined in section 5.6 Audio Latency , of 20 milliseconds or less, over 5 measurements with a Mean Absolute Deviation less than 5 milliseconds over the speaker to microphone path.
- [C-SR-2] Are STRONGLY RECOMMENDED to meet the Pro Audio requirements for continuous round-trip audio latency, cold input latency and cold output latency and USB audio requirements using the AAudio native audio API over the MMAP path.
- [C-SR-3] Are STRONGLY RECOMMENDED to provide a consistent level of CPU performance while audio is active and CPU load is varying. This should be tested using the Android app SynthMark . SynthMark uses a software synthesizer running on a simulated audio framework that measures system performance. The SynthMark app needs to be run using the “Automated Test” option and achieve the following results:
- voicemark.90 >= 32 voices
- latencymark.fixed.little <= 15 msec
- latencymark.dynamic.little <= 50 msec
See the SynthMark documentation for an explanation of the benchmarks.
- SHOULD minimize audio clock inaccuracy and drift relative to standard time.
- SHOULD minimize audio clock drift relative to the CPU
CLOCK_MONOTONIC
when both are active. - SHOULD minimize audio latency over on-device transducers.
- SHOULD minimize audio latency over USB digital audio.
- SHOULD document audio latency measurements over all paths.
- SHOULD minimize jitter in audio buffer completion callback entry times, as this affects usable percentage of full CPU bandwidth by the callback.
- SHOULD provide zero audio glitches under normal use at reported latency.
- SHOULD provide zero inter-channel latency difference.
- SHOULD minimize MIDI mean latency over all transports.
- SHOULD minimize MIDI latency variability under load (jitter) over all transports.
- SHOULD provide accurate MIDI timestamps over all transports.
- SHOULD minimize audio signal noise over on-device transducers, including the period immediately after cold start.
- SHOULD provide zero audio clock difference between the input and output sides of corresponding end-points, when both are active. Examples of corresponding end-points include the on-device microphone and speaker, or the audio jack input and output.
- SHOULD handle audio buffer completion callbacks for the input and output sides of corresponding end-points on the same thread when both are active, and enter the output callback immediately after the return from the input callback. Or if it is not feasible to handle the callbacks on the same thread, then enter the output callback shortly after entering the input callback to permit the application to have a consistent timing of the input and output sides.
- SHOULD minimize the phase difference between HAL audio buffering for the input and output sides of corresponding end-points.
- SHOULD minimize touch latency.
- SHOULD minimize touch latency variability under load (jitter).
- SHOULD have a latency from touch input to audio output of less than or equal to 40 ms.
If device implementations meet all of the above requirements, they:
- [C-SR-4] STRONGLY RECOMMENDED to report support for feature
android.hardware.audio.pro
via theandroid.content.pm.PackageManager
class.
If device implementations include a 4 conductor 3.5mm audio jack, they:
- [C-2-1] MUST have a mean Continuous Round-trip Audio Latency, as defined in section 5.6 Audio Latency , of 20 milliseconds or less, over 5 measurements with a Mean Absolute Deviation less than 5 milliseconds over the audio jack path.
- [C-SR-5] STRONGLY RECOMMENDED to comply with section Mobile device (jack) specifications of the Wired Audio Headset Specification (v1.1) .
If device implementations omit a 4 conductor 3.5mm audio jack and include a USB port(s) supporting USB host mode, they:
- [C-3-1] MUST implement the USB audio class.
- [C-3-2] MUST have a mean Continuous Round-trip Audio Latency of 25 milliseconds or less, over 5 measurements with a Mean Absolute Deviation less than 5 milliseconds over the USB host mode port using USB audio class. (This can be measured using a USB-3.5mm adapter and an Audio Loopback Dongle, or using a USB audio interface with patch cables connecting the inputs to outputs).
- [C-SR-6] Are STRONGLY RECOMMENDED to support simultaneous I/O up to 8 channels each direction, 96 kHz sample rate, and 24-bit or 32-bit depth, when used with USB audio peripherals that also support these requirements.
- [C-SR-7] Are STRONGLY RECOMMENDED to meet this group of requirements using the AAudio native audio API over the MMAP path.
If device implementations include an HDMI port, they:
- SHOULD support output in stereo and eight channels at 20-bit or 24-bit depth and 192 kHz without bit-depth loss or resampling, in at least one configuration.
5.11. Capture for Unprocessed
Android includes support for recording of unprocessed audio via the android.media.MediaRecorder.AudioSource.UNPROCESSED
audio source. In OpenSL ES, it can be accessed with the record preset SL_ANDROID_RECORDING_PRESET_UNPROCESSED
.
If device implementations intent to support unprocessed audio source and make it available to third-party apps, they:
[C-1-1] MUST report the support through the
android.media.AudioManager
property PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED .[C-1-2] MUST exhibit approximately flat amplitude-versus-frequency characteristics in the mid-frequency range: specifically ±10 dB from 100 Hz to 7000 Hz for each and every microphone used to record the unprocessed audio source.
[C-1-3] MUST exhibit amplitude levels in the low frequency range: specifically from ±20 dB from 5 z to 100 Hz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.
[C-1-4] MUST exhibit amplitude levels in the high frequency range: specifically from ±30 dB from 7000 Hz to 22 KHz compared to the mid-frequency range for each and every microphone used to record the unprocessed audio source.
[C-1-5] MUST set audio input sensitivity such that a 1000 Hz sinusoidal tone source played at 94 dB Sound Pressure Level (SPL) yields a response with RMS of 520 for 16 bit-samples (or -36 dB Full Scale for floating point/double precision samples) for each and every microphone used to record the unprocessed audio source.
[C-1-6] MUST have a signal-to-noise ratio (SNR) at 60 dB or higher for each and every microphone used to record the unprocessed audio source. (whereas the SNR is measured as the difference between 94 dB SPL and equivalent SPL of self noise, A-weighted).
[C-1-7] MUST have a total harmonic distortion (THD) less than be less than 1% for 1 kHZ at 90 dB SPL input level at each and every microphone used to record the unprocessed audio source.
[C-1-8] MUST not have any other signal processing (eg Automatic Gain Control, High Pass Filter, or Echo cancellation) in the path other than a level multiplier to bring the level to desired range. به عبارت دیگر:
- [C-1-9] If any signal processing is present in the architecture for any reason, it MUST be disabled and effectively introduce zero delay or extra latency to the signal path.
- [C-1-10] The level multiplier, while allowed to be on the path, MUST NOT introduce delay or latency to the signal path.
All SPL measurements are made directly next to the microphone under test. For multiple microphone configurations, these requirements apply to each microphone.
If device implementations declare android.hardware.microphone
but do not support unprocessed audio source, they:
- [C-2-1] MUST return
null
for theAudioManager.getProperty(PROPERTY_SUPPORT_AUDIO_SOURCE_UNPROCESSED)
API method, to properly indicate the lack of support. - [C-SR-1] are still STRONGLY RECOMMENDED to satisfy as many of the requirements for the signal path for the unprocessed recording source.
6. Developer Tools and Options Compatibility
6.1. ابزارهای توسعه دهنده
Device implementations:
- [C-0-1] MUST support the Android Developer Tools provided in the Android SDK.
- [C-0-2] MUST support adb as documented in the Android SDK and the shell commands provided in the AOSP, which can be used by app developers, including
dumpsys
cmd stats
- [C-0-11] MUST support the shell command
cmd testharness
. Upgrading device implementations from an earlier Android version without a persistent data block MAY be exempted from C-0-11. - [C-0-3] MUST NOT alter the format or the contents of device system events (batterystats , diskstats, fingerprint, graphicsstats, netstats, notification, procstats) logged via the dumpsys command.
- [C-0-10] MUST record, without omission, and make the following events accessible and available to the
cmd stats
shell command and theStatsManager
System API class.- ActivityForegroundStateChanged
- AnomalyDetected
- AppBreadcrumbReported
- AppCrashOccurred
- AppStartOccurred
- BatteryLevelChanged
- BatterySaverModeStateChanged
- BleScanResultReceived
- BleScanStateChanged
- ChargingStateChanged
- DeviceIdleModeStateChanged
- ForegroundServiceStateChanged
- GpsScanStateChanged
- JobStateChanged
- PluggedStateChanged
- ScheduledJobStateChanged
- ScreenStateChanged
- SyncStateChanged
- SystemElapsedRealtime
- UidProcessStateChanged
- WakelockStateChanged
- WakeupAlarmOccurred
- WifiLockStateChanged
- WifiMulticastLockStateChanged
- WifiScanStateChanged
- [C-0-4] MUST have the device-side adb daemon be inactive by default and there MUST be a user-accessible mechanism to turn on the Android Debug Bridge.
- [C-0-5] MUST support secure adb. Android includes support for secure adb. Secure adb enables adb on known authenticated hosts.
- [C-0-6] MUST provide a mechanism allowing adb to be connected from a host machine. به طور مشخص:
If device implementations without a USB port support peripheral mode, they:
- [C-3-1] MUST implement adb via local-area network (such as Ethernet or Wi-Fi).
- [C-3-2] MUST provide drivers for Windows 7, 8 and 10, allowing developers to connect to the device using the adb protocol.
If device implementations support adb connections to a host machine via Wi-Fi, they:
- [C-4-1] MUST have the
AdbManager#isAdbWifiSupported()
method returntrue
.
If device implementations support adb connections to a host machine via Wi-Fi and includes at least one camera, they:
- [C-5-1] MUST have the
AdbManager#isAdbWifiQrSupported()
method returntrue
.
- [C-0-2] MUST support adb as documented in the Android SDK and the shell commands provided in the AOSP, which can be used by app developers, including
Dalvik Debug Monitor Service (ddms)
- [C-0-7] MUST support all ddms features as documented in the Android SDK. As ddms uses adb, support for ddms SHOULD be inactive by default, but MUST be supported whenever the user has activated the Android Debug Bridge, as above.
- [C-0-8] MUST include the Monkey framework and make it available for applications to use.
- [C-0-9] MUST support the systrace tool as documented in the Android SDK. Systrace must be inactive by default and there MUST be a user-accessible mechanism to turn on Systrace.
- [C-SR-1] Are STRONGLY RECOMMENDED to expose a
/system/bin/perfetto
binary to the shell user which cmdline complies with the perfetto documentation . - [C-SR-2] The perfetto binary is STRONGLY RECOMMENDED to accept as input a protobuf config that complies with the schema defined in the perfetto documentation .
- [C-SR-3] The perfetto binary is STRONGLY RECOMMENDED to write as output a protobuf trace that complies with the schema defined in the perfetto documentation .
- [C-SR-4] Are STRONGLY RECOMMENDED to provide, through the perfetto binary, at least the data sources described in the perfetto documentation .
- [C-SR-1] Are STRONGLY RECOMMENDED to expose a
- [C-0-10] MUST write a
LMK_KILL_OCCURRED_FIELD_NUMBER
Atom to the statsd log when an app is terminated by the Low Memory Killer .
- [C-0-10] MUST write a
Test Harness Mode If device implementations support the shell command
cmd testharness
and runcmd testharness enable
, they:- [C-2-1] MUST return
true
forActivityManager.isRunningInUserTestHarness()
- [C-2-2] MUST implement Test Harness Mode as described in Test Harness Mode documentation .
- [C-2-1] MUST return
If device implementations report the support of Vulkan 1.0 or higher via the android.hardware.vulkan.version
feature flags, they:
- [C-1-1] MUST provide an affordance for the app developer to enable/disable GPU debug layers.
- [C-1-2] MUST, when the GPU debug layers are enabled, enumerate layers in libraries provided by external tools (ie not part of the platform or application package) found in debuggable applications' base directory to support vkEnumerateInstanceLayerProperties() and vkCreateInstance() API methods.
6.2. گزینه های توسعه دهنده
Android includes support for developers to configure application development-related settings.
Device implementations MUST provide a consistent experience for Developer Options, they:
- [C-0-1] MUST honor the android.settings.APPLICATION_DEVELOPMENT_SETTINGS intent to show application development-related settings. The upstream Android implementation hides the Developer Options menu by default and enables users to launch Developer Options after pressing seven (7) times on the Settings > About Device > Build Number menu item.
- [C-0-2] MUST hide Developer Options by default.
- [C-0-3] MUST provide a clear mechanism that does not give preferential treatment to one third-party app as opposed to another to enable Developer Options. MUST provide a public visible document or website that describes how to enable Developer Options. This document or website MUST be linkable from the Android SDK documents.
- SHOULD have an ongoing visual notification to the user when Developer Options is enabled and the safety of the user is of concern.
- MAY temporarily limit access to the Developer Options menu, by visually hiding or disabling the menu, to prevent distraction for scenarios where the safety of the user is of concern.
7. Hardware Compatibility
If a device includes a particular hardware component that has a corresponding API for third-party developers:
- [C-0-1] The device implementation MUST implement that API as described in the Android SDK documentation.
If an API in the SDK interacts with a hardware component that is stated to be optional and the device implementation does not possess that component:
- [C-0-2] Complete class definitions (as documented by the SDK) for the component APIs MUST still be presented.
- [C-0-3] The API's behaviors MUST be implemented as no-ops in some reasonable fashion.
- [C-0-4] API methods MUST return null values where permitted by the SDK documentation.
- [C-0-5] API methods MUST return no-op implementations of classes where null values are not permitted by the SDK documentation.
- [C-0-6] API methods MUST NOT throw exceptions not documented by the SDK documentation.
- [C-0-7] Device implementations MUST consistently report accurate hardware configuration information via the
getSystemAvailableFeatures()
andhasSystemFeature(String)
methods on the android.content.pm.PackageManager class for the same build fingerprint.
A typical example of a scenario where these requirements apply is the telephony API: Even on non-phone devices, these APIs must be implemented as reasonable no-ops.
7.1. Display and Graphics
Android includes facilities that automatically adjust application assets and UI layouts appropriately for the device to ensure that third-party applications run well on a variety of hardware configurations . On the Android-compatible display(s) where all third-party Android-compatible applications can run, device implementations MUST properly implement these APIs and behaviors, as detailed in this section.
The units referenced by the requirements in this section are defined as follows:
- physical diagonal size . The distance in inches between two opposing corners of the illuminated portion of the display.
- dots per inch (dpi) . The number of pixels encompassed by a linear horizontal or vertical span of 1”. Where dpi values are listed, both horizontal and vertical dpi must fall within the range.
- aspect ratio . The ratio of the pixels of the longer dimension to the shorter dimension of the screen. For example, a display of 480x854 pixels would be 854/480 = 1.779, or roughly “16:9”.
- density-independent pixel (dp) . The virtual pixel unit normalized to a 160 dpi screen, calculated as: pixels = dps * (density/160).
7.1.1. Screen Configuration
7.1.1.1. Screen Size and Shape
The Android UI framework supports a variety of different logical screen layout sizes, and allows applications to query the current configuration's screen layout size via Configuration.screenLayout
with the SCREENLAYOUT_SIZE_MASK
and Configuration.smallestScreenWidthDp
.
Device implementations:
[C-0-1] MUST report the correct layout size for the
Configuration.screenLayout
as defined in the Android SDK documentation. Specifically, device implementations MUST report the correct logical density-independent pixel (dp) screen dimensions as below:- Devices with the
Configuration.uiMode
set as any value other than UI_MODE_TYPE_WATCH, and reporting asmall
size for theConfiguration.screenLayout
, MUST have at least 426 dp x 320 dp. - Devices reporting a
normal
size for theConfiguration.screenLayout
, MUST have at least 480 dp x 320 dp. - Devices reporting a
large
size for theConfiguration.screenLayout
, MUST have at least 640 dp x 480 dp. - Devices reporting a
xlarge
size for theConfiguration.screenLayout
, MUST have at least 960 dp x 720 dp.
- Devices with the
[C-0-2] MUST correctly honor applications' stated support for screen sizes through the <
supports-screens
> attribute in the AndroidManifest.xml, as described in the Android SDK documentation.MAY have the Android-compatible display(s) with rounded corners.
If device implementations support UI_MODE_TYPE_NORMAL
and include Android-compatible display(s) with rounded corners, they:
[C-1-1] MUST ensure that at least one of the following requirements is met:
- The radius of the rounded corners is less than or equal to 38 dp.
- When a 15 dp by 15 dp box is anchored at each corner of the logical display, at least one pixel of each box is visible on the screen.
SHOULD include user affordance to switch to the display mode with the rectangular corners.
If device implementations include an Android-compatible display(s) that is foldable, or includes a folding hinge between multiple display panels and makes such display(s) available to render third-party apps, they:
- [C-2-1] MUST implement the latest available stable version of the extensions API or the stable version of sidecar API to be used by Window Manager Jetpack library.
If device implementations include an Android-compatible display(s) that is foldable, or includes a folding hinge between multiple display panels and if the hinge or fold crosses a fullscreen application window, they:
- [C-3-1] MUST report the position, bounds and state of hinge or fold through extensions or sidecar APIs to the application.
For details on correctly implementing the sidecar or extension APIs refer to the public documentation of Window Manager Jetpack .
7.1.1.2. Screen Aspect Ratio
While there is no restriction to the aspect ratio of the physical display for the Android-compatible display(s), the aspect ratio of the logical display where third-party apps are rendered, which can be derived from the height and width values reported through the view.Display
APIs and Configuration APIs, MUST meet the following requirements:
[C-0-1] Device implementations with
Configuration.uiMode
set toUI_MODE_TYPE_NORMAL
MUST have an aspect ratio value less than or equal to 1.86 (roughly 16:9), unless the app meets one of the following conditions:- The app has declared that it supports a larger screen aspect ratio through the
android.max_aspect
metadata value. - The app declares it is resizeable via the android:resizeableActivity attribute.
- The app targets API level 24 or higher and does not declare an
android:maxAspectRatio
that would restrict the allowed aspect ratio.
- The app has declared that it supports a larger screen aspect ratio through the
[C-0-3] Device implementations with the
Configuration.uiMode
set asUI_MODE_TYPE_WATCH
MUST have an aspect ratio value set as 1.0 (1:1).
7.1.1.3. Screen Density
The Android UI framework defines a set of standard logical densities to help application developers target application resources.
[C-0-1] By default, device implementations MUST report only one of the Android framework densities that are listed on
DisplayMetrics
through theDENSITY_DEVICE_STABLE
API and this value MUST NOT change at any time; however, the device MAY report a different arbitrary density according to the display configuration changes made by the user (for example, display size) set after initial boot.Device implementations SHOULD define the standard Android framework density that is numerically closest to the physical density of the screen, unless that logical density pushes the reported screen size below the minimum supported. If the standard Android framework density that is numerically closest to the physical density results in a screen size that is smaller than the smallest supported compatible screen size (320 dp width), device implementations SHOULD report the next lowest standard Android framework density.
If there is an affordance to change the display size of the device:
- [C-1-1] The display size MUST NOT be scaled any larger than 1.5 times the native density or produce an effective minimum screen dimension smaller than 320dp (equivalent to resource qualifier sw320dp), whichever comes first.
- [C-1-2] Display size MUST NOT be scaled any smaller than 0.85 times the native density.
- To ensure good usability and consistent font sizes, it is RECOMMENDED that the following scaling of Native Display options be provided (while complying with the limits specified above)
- Small: 0.85x
- Default: 1x (Native display scale)
- Large: 1.15x
- Larger: 1.3x
- Largest 1.45x
7.1.2. Display Metrics
If device implementations include the Android-compatible display(s) or video output to the Android-compatible display screen(s), they:
- [C-1-1] MUST report correct values for all Android-compatible display metrics defined in the
android.util.DisplayMetrics
API.
If device implementations does not include an embedded screen or video output, they:
- [C-2-1] MUST report correct values of the Android-compatible display as defined in the
android.util.DisplayMetrics
API for the emulated defaultview.Display
.
7.1.3. Screen Orientation
Device implementations:
- [C-0-1] MUST report which screen orientations they support (
android.hardware.screen.portrait
and/orandroid.hardware.screen.landscape
) and MUST report at least one supported orientation. For example, a device with a fixed orientation landscape screen, such as a television or laptop, SHOULD only reportandroid.hardware.screen.landscape
. - [C-0-2] MUST report the correct value for the device's current orientation, whenever queried via the
android.content.res.Configuration.orientation
,android.view.Display.getOrientation()
, or other APIs.
If device implementations support both screen orientations, they:
- [C-1-1] MUST support dynamic orientation by applications to either portrait or landscape screen orientation. That is, the device must respect the application's request for a specific screen orientation.
- [C-1-2] MUST NOT change the reported screen size or density when changing orientation.
- MAY select either portrait or landscape orientation as the default.
7.1.4. 2D and 3D Graphics Acceleration
7.1.4.1 OpenGL ES
Device implementations:
- [C-0-1] MUST correctly identify the supported OpenGL ES versions (1.1, 2.0, 3.0, 3.1, 3.2) through the managed APIs (such as via the
GLES10.getString()
method) and the native APIs. - [C-0-2] MUST include the support for all the corresponding managed APIs and native APIs for every OpenGL ES versions they identified to support.
If device implementations include a screen or video output, they:
- [C-1-1] MUST support both OpenGL ES 1.1 and 2.0, as embodied and detailed in the Android SDK documentation .
- [C-SR-1] Are STRONGLY RECOMMENDED to support OpenGL ES 3.1.
- SHOULD support OpenGL ES 3.2.
The OpenGL ES dEQP tests are partitioned into a number of test lists, each with an associated date/version number. These are in the Android source tree at external/deqp/android/cts/main/glesXX-master-YYYY-MM-DD.txt
. A device that supports OpenGL ES at a self-reported level indicates that it can pass the dEQP tests in all test lists from this level and earlier.
If device implementations support any of the OpenGL ES versions, they:
- [C-2-1] MUST report via the OpenGL ES managed APIs and native APIs any other OpenGL ES extensions they have implemented, and conversely MUST NOT report extension strings that they do not support.
- [C-2-2] MUST support the
EGL_KHR_image
,EGL_KHR_image_base
,EGL_ANDROID_image_native_buffer
,EGL_ANDROID_get_native_client_buffer
,EGL_KHR_wait_sync
,EGL_KHR_get_all_proc_addresses
,EGL_ANDROID_presentation_time
,EGL_KHR_swap_buffers_with_damage
,EGL_ANDROID_recordable
, andEGL_ANDROID_GLES_layers
extensions. - [C-2-3] MUST report the maximum version of the OpenGL ES dEQP tests supported via the
android.software.opengles.deqp.level
feature flag. - [C-2-4] MUST at least support version 132383489 (from Mar 1st, 2020) as reported in the
android.software.opengles.deqp.level
feature flag. - [C-2-5] MUST pass all OpenGL ES dEQP Tests in the test lists between version 132383489 and the version specified in the
android.software.opengles.deqp.level
feature flag, for each supported OpenGL ES version. - [C-SR-2] Are STRONGLY RECOMMENDED to support the
EGL_KHR_partial_update
andOES_EGL_image_external
extensions. - SHOULD accurately report via the
getString()
method, any texture compression format that they support, which is typically vendor-specific.
If device implementations declare support for OpenGL ES 3.0, 3.1, or 3.2, they:
- [C-3-1] MUST export the corresponding function symbols for these version in addition to the OpenGL ES 2.0 function symbols in the libGLESv2.so library.
- [C-SR-3] Are STRONGLY RECOMMENDED to support the
OES_EGL_image_external_essl3
extension.
If device implementations support OpenGL ES 3.2, they:
- [C-4-1] MUST support the OpenGL ES Android Extension Pack in its entirety.
If device implementations support the OpenGL ES Android Extension Pack in its entirety, they:
- [C-5-1] MUST identify the support through the
android.hardware.opengles.aep
feature flag.
If device implementations expose support for the EGL_KHR_mutable_render_buffer
extension, they:
- [C-6-1] MUST also support the
EGL_ANDROID_front_buffer_auto_refresh
extension.
7.1.4.2 Vulkan
Android includes support for Vulkan , a low-overhead, cross-platform API for high-performance 3D graphics.
If device implementations support OpenGL ES 3.1, they:
- [C-SR-1] Are STRONGLY RECOMMENDED to include support for Vulkan 1.1.
If device implementations include a screen or video output, they:
- SHOULD include support for Vulkan 1.1.
The Vulkan dEQP tests are partitioned into a number of test lists, each with an associated date/version. These are in the Android source tree at external/deqp/android/cts/main/vk-master-YYYY-MM-DD.txt
. A device that supports Vulkan at a self-reported level indicates that it can pass the dEQP tests in all test lists from this level and earlier.
If device implementations include support for Vulkan 1.0 or higher, they:
- [C-1-1] MUST report the correct integer value with the
android.hardware.vulkan.level
andandroid.hardware.vulkan.version
feature flags. - [C-1-2] MUST enumerate, at least one
VkPhysicalDevice
for the Vulkan native APIvkEnumeratePhysicalDevices()
. - [C-1-3] MUST fully implement the Vulkan 1.0 APIs for each enumerated
VkPhysicalDevice
. - [C-1-4] MUST enumerate layers, contained in native libraries named as
libVkLayer*.so
in the application package's native library directory, through the Vulkan native APIsvkEnumerateInstanceLayerProperties()
andvkEnumerateDeviceLayerProperties()
. - [C-1-5] MUST NOT enumerate layers provided by libraries outside of the application package, or provide other ways of tracing or intercepting the Vulkan API, unless the application has the
android:debuggable
attribute set astrue
. - [C-1-6] MUST report all extension strings that they do support via the Vulkan native APIs , and conversely MUST NOT report extension strings that they do not correctly support.
- [C-1-7] MUST support the VK_KHR_surface, VK_KHR_android_surface, VK_KHR_swapchain, and VK_KHR_incremental_present extensions.
- [C-1-8] MUST report the maximum version of the Vulkan dEQP Tests supported via the
android.software.vulkan.deqp.level
feature flag. - [C-1-9] MUST at least support version
132317953
(from Mar 1st, 2019) as reported in theandroid.software.vulkan.deqp.level
feature flag. - [C-1-10] MUST pass all Vulkan dEQP Tests in the test lists between version
132317953
and the version specified in theandroid.software.vulkan.deqp.level
feature flag. - [C-1-11] MUST NOT enumerate support for the VK_KHR_video_queue, VK_KHR_video_decode_queue, or VK_KHR_video_encode_queue extensions.
- [C-SR-2] Are STRONGLY RECOMMENDED to support the VK_KHR_driver_properties and VK_GOOGLE_display_timing extensions.
If device implementations do not include support for Vulkan 1.0, they:
- [C-2-1] MUST NOT declare any of the Vulkan feature flags (eg
android.hardware.vulkan.level
,android.hardware.vulkan.version
). - [C-2-2] MUST NOT enumerate any
VkPhysicalDevice
for the Vulkan native APIvkEnumeratePhysicalDevices()
.
If device implementations include support for Vulkan 1.1 and declare any of the Vulkan feature flags, they:
- [C-3-1] MUST expose support for the
SYNC_FD
external semaphore and handle types and theVK_ANDROID_external_memory_android_hardware_buffer
extension.
7.1.4.3 RenderScript
- [C-0-1] Device implementations MUST support Android RenderScript , as detailed in the Android SDK documentation.
7.1.4.4 2D Graphics Acceleration
Android includes a mechanism for applications to declare that they want to enable hardware acceleration for 2D graphics at the Application, Activity, Window, or View level through the use of a manifest tag android:hardwareAccelerated or direct API calls.
Device implementations:
- [C-0-1] MUST enable hardware acceleration by default, and MUST disable hardware acceleration if the developer so requests by setting android:hardwareAccelerated="false” or disabling hardware acceleration directly through the Android View APIs.
- [C-0-2] MUST exhibit behavior consistent with the Android SDK documentation on hardware acceleration .
Android includes a TextureView object that lets developers directly integrate hardware-accelerated OpenGL ES textures as rendering targets in a UI hierarchy.
Device implementations:
- [C-0-3] MUST support the TextureView API, and MUST exhibit consistent behavior with the upstream Android implementation.
7.1.4.5 Wide-gamut Displays
If device implementations claim support for wide-gamut displays through Configuration.isScreenWideColorGamut()
, they:
- [C-1-1] MUST have a color-calibrated display.
- [C-1-2] MUST have a display whose gamut covers the sRGB color gamut entirely in CIE 1931 xyY space.
- [C-1-3] MUST have a display whose gamut has an area of at least 90% of DCI-P3 in CIE 1931 xyY space.
- [C-1-4] MUST support OpenGL ES 3.1 or 3.2 and report it properly.
- [C-1-5] MUST advertise support for the
EGL_KHR_no_config_context
,EGL_EXT_pixel_format_float
,EGL_KHR_gl_colorspace
,EGL_EXT_gl_colorspace_scrgb
,EGL_EXT_gl_colorspace_scrgb_linear
,EGL_EXT_gl_colorspace_display_p3
,EGL_EXT_gl_colorspace_display_p3_linear
, andEGL_EXT_gl_colorspace_display_p3_passthrough
extensions. - [C-SR-1] Are STRONGLY RECOMMENDED to support
GL_EXT_sRGB
.
Conversely, if device implementations do not support wide-gamut displays, they:
- [C-2-1] SHOULD cover 100% or more of sRGB in CIE 1931 xyY space, although the screen color gamut is undefined.
7.1.5. Legacy Application Compatibility Mode
Android specifies a “compatibility mode” in which the framework operates in a 'normal' screen size equivalent (320dp width) mode for the benefit of legacy applications not developed for old versions of Android that pre-date screen-size independence.
7.1.6. Screen Technology
The Android platform includes APIs that allow applications to render rich graphics to an Android-compatible display. Devices MUST support all of these APIs as defined by the Android SDK unless specifically allowed in this document.
All of a device implementation's Android-compatible displays:
- [C-0-1] MUST be capable of rendering 16-bit color graphics.
- SHOULD support displays capable of 24-bit color graphics.
- [C-0-2] MUST be capable of rendering animations.
- [C-0-3] MUST have a pixel aspect ratio (PAR) between 0.9 and 1.15. That is, the pixel aspect ratio MUST be near square (1.0) with a 10 ~ 15% tolerance.
7.1.7. Secondary Displays
Android includes support for secondary Android-compatible displays to enable media sharing capabilities and developer APIs for accessing external displays.
If device implementations support an external display either via a wired, wireless, or an embedded additional display connection, they:
- [C-1-1] MUST implement the
DisplayManager
system service and API as described in the Android SDK documentation.
7.2. دستگاه های ورودی
Device implementations:
- [C-0-1] MUST include an input mechanism, such as a touchscreen or non-touch navigation , to navigate between the UI elements.
7.2.1. صفحه کلید
If device implementations include support for third-party Input Method Editor (IME) applications, they:
- [C-1-1] MUST declare the
android.software.input_methods
feature flag. - [C-1-2] MUST implement fully
Input Management Framework
- [C-1-3] MUST have a preinstalled software keyboard.
Device implementations:
- [C-0-1] MUST NOT include a hardware keyboard that does not match one of the formats specified in android.content.res.Configuration.keyboard (QWERTY or 12-key).
- SHOULD include additional soft keyboard implementations.
- MAY include a hardware keyboard.
7.2.2. Non-touch Navigation
Android includes support for d-pad, trackball, and wheel as mechanisms for non-touch navigation.
Device implementations:
- [C-0-1] MUST report the correct value for android.content.res.Configuration.navigation .
If device implementations lack non-touch navigations, they:
- [C-1-1] MUST provide a reasonable alternative user interface mechanism for the selection and editing of text, compatible with Input Management Engines. The upstream Android open source implementation includes a selection mechanism suitable for use with devices that lack non-touch navigation inputs.
7.2.3. Navigation Keys
The Home , Recents , and Back functions typically provided via an interaction with a dedicated physical button or a distinct portion of the touch screen, are essential to the Android navigation paradigm and therefore, device implementations:
- [C-0-1] MUST provide a user affordance to launch installed applications that have an activity with the
<intent-filter>
set withACTION=MAIN
andCATEGORY=LAUNCHER
orCATEGORY=LEANBACK_LAUNCHER
for Television device implementations. The Home function SHOULD be the mechanism for this user affordance. - SHOULD provide buttons for the Recents and Back function.
If the Home, Recents, or Back functions are provided, they:
- [C-1-1] MUST be accessible with a single action (eg tap, double-click or gesture) when any of them are accessible.
- [C-1-2] MUST provide a clear indication of which single action would trigger each function. Having a visible icon imprinted on the button, showing a software icon on the navigation bar portion of the screen, or walking the user through a guided step-by-step demo flow during the out-of-box setup experience are examples of such an indication.
Device implementations:
- [C-SR-1] are STRONGLY RECOMMENDED to not provide the input mechanism for the Menu function as it is deprecated in favor of action bar since Android 4.0.
If device implementations provide the Menu function, they:
- [C-2-1] MUST display the action overflow button whenever the action overflow menu popup is not empty and the action bar is visible.
- [C-2-2] MUST NOT modify the position of the action overflow popup displayed by selecting the overflow button in the action bar, but MAY render the action overflow popup at a modified position on the screen when it is displayed by selecting the Menu تابع
If device implementations do not provide the Menu function, for backwards compatibility, they:
- [C-3-1] MUST make the Menu function available to applications when
targetSdkVersion
is less than 10, either by a physical button, a software key, or gestures. This Menu function should be accessible unless hidden together with other navigation functions.
If device implementations provide the Assist function , they:
- [C-4-1] MUST make the Assist function accessible with a single action (eg tap, double-click or gesture) when other navigation keys are accessible.
- [C-SR-2] STRONGLY RECOMMENDED to use long press on HOME function as this designated interaction.
If device implementations use a distinct portion of the screen to display the navigation keys, they:
- [C-5-1] Navigation keys MUST use a distinct portion of the screen, not available to applications, and MUST NOT obscure or otherwise interfere with the portion of the screen available to applications.
- [C-5-2] MUST make available a portion of the display to applications that meets the requirements defined in section 7.1.1 .
- [C-5-3] MUST honor the flags set by the app through the
View.setSystemUiVisibility()
API method, so that this distinct portion of the screen (aka the navigation bar) is properly hidden away as documented in the SDK.
If the navigation function is provided as an on-screen, gesture-based action:
- [C-6-1]
WindowInsets#getMandatorySystemGestureInsets()
MUST only be used to report the Home gesture recognition area. - [C-6-2] Gestures that start within an exclusion rect as provided by the foreground application via
View#setSystemGestureExclusionRects()
, but outside ofWindowInsets#getMandatorySystemGestureInsets()
, MUST NOT be intercepted for the navigation function as long as the exclusion rect is allowed within the max exclusion limit as specified in the documentation forView#setSystemGestureExclusionRects()
. - [C-6-3] MUST send the foreground app a
MotionEvent.ACTION_CANCEL
event once touches start being intercepted for a system gesture, if the foreground app was previously sent anMotionEvent.ACTION_DOWN
event. - [C-6-4] MUST provide a user affordance to switch to an on-screen, button-based navigation (for example, in Settings).
- SHOULD provide Home function as a swipe up from the bottom edge of the current orientation of the screen.
- SHOULD provide Recents function as a swipe up and hold before release, from the same area as the Home gesture.
- Gestures that start within
WindowInsets#getMandatorySystemGestureInsets()
SHOULD NOT be affected by exclusion rects provided by the foreground application viaView#setSystemGestureExclusionRects()
.
If a navigation function is provided from anywhere on the left and right edges of the current orientation of the screen:
- [C-7-1] The navigation function MUST be Back and provided as a swipe from both left and right edges of the current orientation of the screen.
- [C-7-2] If custom swipeable system panels are provided on the left or right edges, they MUST be placed within the top 1/3rd of the screen with a clear, persistent visual indication that dragging in would invoke the aforementioned panels, and hence not Back. A system panel MAY be configured by a user such that it lands below the top 1/3rd of the screen edge(s) but the system panel MUST NOT use longer than 1/3rd of the edge(s).
- [C-7-3] When the foreground app has either the View.SYSTEM_UI_FLAG_IMMERSIVE, View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY, WindowInsetsController.BEHAVIOR_DEFAULT, or WindowInsetsController.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE flags set, swiping from the edges MUST behave as implemented in AOSP, which is documented in the SDK .
- [C-7-4] When the foreground app has either the View.SYSTEM_UI_FLAG_IMMERSIVE, View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY, WindowInsetsController.BEHAVIOR_DEFAULT, or WindowInsetsController.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE flags set, custom swipeable system panels MUST be hidden until the user brings in or un-dims the system bars (aka navigation and status bar) as implemented in AOSP.
7.2.4. Touchscreen Input
Android includes support for a variety of pointer input systems, such as touchscreens, touch pads, and fake touch input devices. Touchscreen-based device implementations are associated with a display such that the user has the impression of directly manipulating items on screen. Since the user is directly touching the screen, the system does not require any additional affordances to indicate the objects being manipulated.
Device implementations:
- SHOULD have a pointer input system of some kind (either mouse-like or touch).
- SHOULD support fully independently tracked pointers.
If device implementations include a touchscreen (single-touch or better) on a primary Android-compatible display, they:
- [C-1-1] MUST report
TOUCHSCREEN_FINGER
for theConfiguration.touchscreen
API field. - [C-1-2] MUST report the
android.hardware.touchscreen
andandroid.hardware.faketouch
feature flags.
If device implementations include a touchscreen that can track more than a single touch on a primary Android-compatible display, they:
- [C-2-1] MUST report the appropriate feature flags
android.hardware.touchscreen.multitouch
,android.hardware.touchscreen.multitouch.distinct
,android.hardware.touchscreen.multitouch.jazzhand
corresponding to the type of the specific touchscreen on the دستگاه
If device implementations rely on an external input device such as mouse or trackball (ie not directly touching the screen) for input on a primary Android-compatible display and meet the fake touch requirements in section 7.2.5 , they:
- [C-3-1] MUST NOT report any feature flag starting with
android.hardware.touchscreen
. - [C-3-2] MUST report only
android.hardware.faketouch
. - [C-3-3] MUST report
TOUCHSCREEN_NOTOUCH
for theConfiguration.touchscreen
API field.
7.2.5. Fake Touch Input
Fake touch interface provides a user input system that approximates a subset of touchscreen capabilities. For example, a mouse or remote control that drives an on-screen cursor approximates touch, but requires the user to first point or focus then click. Numerous input devices like the mouse, trackpad, gyro-based air mouse, gyro-pointer, joystick, and multi-touch trackpad can support fake touch interactions. Android includes the feature constant android.hardware.faketouch, which corresponds to a high-fidelity non-touch (pointer-based) input device such as a mouse or trackpad that can adequately emulate touch-based input (including basic gesture support), and indicates that the device supports an emulated subset of touchscreen functionality.
If device implementations do not include a touchscreen but include another pointer input system which they want to make available, they:
- SHOULD declare support for the
android.hardware.faketouch
feature flag.
If device implementations declare support for android.hardware.faketouch
, they:
- [C-1-1] MUST report the absolute X and Y screen positions of the pointer location and display a visual pointer on the screen.
- [C-1-2] MUST report touch event with the action code that specifies the state change that occurs on the pointer going down or up on the screen .
- [C-1-3] MUST support pointer down and up on an object on the screen, which allows users to emulate tap on an object on the screen.
- [C-1-4] MUST support pointer down, pointer up, pointer down then pointer up in the same place on an object on the screen within a time threshold, which allows users to emulate double tap on an object on the screen.
- [C-1-5] MUST support pointer down on an arbitrary point on the screen, pointer move to any other arbitrary point on the screen, followed by a pointer up, which allows users to emulate a touch drag.
- [C-1-6] MUST support pointer down then allow users to quickly move the object to a different position on the screen and then pointer up on the screen, which allows users to fling an object on the screen.
If device implementations declare support for android.hardware.faketouch.multitouch.distinct
, they:
- [C-2-1] MUST declare support for
android.hardware.faketouch
. - [C-2-2] MUST support distinct tracking of two or more independent pointer inputs.
If device implementations declare support for android.hardware.faketouch.multitouch.jazzhand
, they:
- [C-3-1] MUST declare support for
android.hardware.faketouch
. - [C-3-2] MUST support distinct tracking of 5 (tracking a hand of fingers) or more pointer inputs fully independently.
7.2.6. Game Controller Support
7.2.6.1. Button Mappings
Device implementations:
- [C-1-1] MUST be capable to map HID events to the corresponding
InputEvent
constants as listed in the below tables. The upstream Android implementation satisfies this requirement.
If device implementations embed a controller or ship with a separate controller in the box that would provide means to input all the events listed in the below tables, they:
- [C-2-1] MUST declare the feature flag
android.hardware.gamepad
دکمه | HID Usage 2 | Android Button |
---|---|---|
A 1 | 0x09 0x0001 | KEYCODE_BUTTON_A (96) |
ب 1 | 0x09 0x0002 | KEYCODE_BUTTON_B (97) |
X 1 | 0x09 0x0004 | KEYCODE_BUTTON_X (99) |
Y 1 | 0x09 0x0005 | KEYCODE_BUTTON_Y (100) |
D-pad up 1 D-pad down 1 | 0x01 0x0039 3 | AXIS_HAT_Y 4 |
D-pad left 1 D-pad right 1 | 0x01 0x0039 3 | AXIS_HAT_X 4 |
Left shoulder button 1 | 0x09 0x0007 | KEYCODE_BUTTON_L1 (102) |
Right shoulder button 1 | 0x09 0x0008 | KEYCODE_BUTTON_R1 (103) |
Left stick click 1 | 0x09 0x000E | KEYCODE_BUTTON_THUMBL (106) |
Right stick click 1 | 0x09 0x000F | KEYCODE_BUTTON_THUMBR (107) |
برگشت 1 | 0x0c 0x0224 | KEYCODE_BACK (4) |
1 KeyEvent
2 The above HID usages must be declared within a Game pad CA (0x01 0x0005).
3 This usage must have a Logical Minimum of 0, a Logical Maximum of 7, a Physical Minimum of 0, a Physical Maximum of 315, Units in Degrees, and a Report Size of 4. The logical value is defined to be the clockwise rotation away from the vertical axis; for example, a logical value of 0 represents no rotation and the up button being pressed, while a logical value of 1 represents a rotation of 45 degrees and both the up and left keys being pressed.
Analog Controls 1 | HID Usage | Android Button |
---|---|---|
Left Trigger | 0x02 0x00C5 | AXIS_LTRIGGER |
Right Trigger | 0x02 0x00C4 | AXIS_RTRIGGER |
Left Joystick | 0x01 0x0030 0x01 0x0031 | AXIS_X AXIS_Y |
Right Joystick | 0x01 0x0032 0x01 0x0035 | AXIS_Z AXIS_RZ |
7.2.7. کنترل از راه دور
See Section 2.3.1 for device-specific requirements.
7.3. حسگرها
If device implementations include a particular sensor type that has a corresponding API for third-party developers, the device implementation MUST implement that API as described in the Android SDK documentation and the Android Open Source documentation on sensors .
Device implementations:
- [C-0-1] MUST accurately report the presence or absence of sensors per the
android.content.pm.PackageManager
class. - [C-0-2] MUST return an accurate list of supported sensors via the
SensorManager.getSensorList()
and similar methods. - [C-0-3] MUST behave reasonably for all other sensor APIs (for example, by returning
true
orfalse
as appropriate when applications attempt to register listeners, not calling sensor listeners when the corresponding sensors are not present; etc.).
If device implementations include a particular sensor type that has a corresponding API for third-party developers, they:
- [C-1-1] MUST report all sensor measurements using the relevant International System of Units (metric) values for each sensor type as defined in the Android SDK documentation.
- [C-1-2] MUST report sensor data with a maximum latency of 100 milliseconds + 2 * sample_time for the case of a sensor stream with a maximum requested latency of 0 ms when the application processor is active. This delay does not include any filtering delays.
- [C-1-3] MUST report the first sensor sample within 400 milliseconds + 2 * sample_time of the sensor being activated. It is acceptable for this sample to have an accuracy of 0.
- [C-1-4] For any API indicated by the Android SDK documentation to be a continuous sensor , device implementations MUST continuously provide periodic data samples that SHOULD have a jitter below 3%, where jitter is defined as the standard deviation of the difference of the reported timestamp values between consecutive events.
- [C-1-5] MUST ensure that the sensor event stream MUST NOT prevent the device CPU from entering a suspend state or waking up from a suspend state.
- [C-1-6] MUST report the event time in nanoseconds as defined in the Android SDK documentation, representing the time the event happened and synchronized with the SystemClock.elapsedRealtimeNano() clock.
- [C-SR-1] Are STRONGLY RECOMMENDED to have timestamp synchronization error below 100 milliseconds, and SHOULD have timestamp synchronization error below 1 millisecond.
- When several sensors are activated, the power consumption SHOULD NOT exceed the sum of the individual sensor's reported power consumption.
The list above is not comprehensive; the documented behavior of the Android SDK and the Android Open Source Documentations on sensors is to be considered authoritative.
If device implementations include a particular sensor type that has a corresponding API for third-party developers, they:
- [C-1-6] MUST set a non-zero resolution for all sensors, and report the value via the
Sensor.getResolution()
API method.
Some sensor types are composite, meaning they can be derived from data provided by one or more other sensors. (Examples include the orientation sensor and the linear acceleration sensor.)
Device implementations:
- SHOULD implement these sensor types, when they include the prerequisite physical sensors as described in sensor types .
If device implementations include a composite sensor, they:
- [C-2-1] MUST implement the sensor as described in the Android Open Source documentation on composite sensors .
If device implementations include a particular sensor type that has a corresponding API for third-party developers and the sensor only reports one value, then device implementations:
- [C-3-1] MUST set the resolution to 1 for the sensor and report the value via the
Sensor.getResolution()
API method.
If device implementations include a particular sensor type which supports SensorAdditionalInfo#TYPE_VEC3_CALIBRATION and the sensor is exposed to third-party developers, they:
- [C-4-1] MUST NOT include any fixed, factory-determined calibration parameters in the data provided.
If device implementations include a combination of 3-axis accelerometer, a 3-axis gyroscope sensor, or a magnetometer sensor, they are:
- [C-SR-2] STRONGLY RECOMMENDED to ensure the accelerometer, gyroscope and magnetometer have a fixed relative position, such that if the device is transformable (eg foldable), the sensor axes remain aligned and consistent with the sensor coordinate system throughout all possible device transformation states.
7.3.1. شتاب سنج
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to include a 3-axis accelerometer.
If device implementations include a 3-axis accelerometer, they:
- [C-1-1] MUST be able to report events up to a frequency of at least 50 Hz.
- [C-1-2] MUST implement and report
TYPE_ACCELEROMETER
sensor. - [C-1-3] MUST comply with the Android sensor coordinate system as detailed in the Android APIs.
- [C-1-4] MUST be capable of measuring from freefall up to four times the gravity(4g) or more on any axis.
- [C-1-5] MUST have a resolution of at least 12-bits.
- [C-1-6] MUST have a standard deviation no greater than 0.05 m/s^, where the standard deviation should be calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate.
- [C-SR-2] are STRONGLY RECOMMENDED to implement the
TYPE_SIGNIFICANT_MOTION
composite sensor. - [C-SR-3] are STRONGLY RECOMMENDED to implement and report
TYPE_ACCELEROMETER_UNCALIBRATED
sensor. Android devices are STRONGLY RECOMMENDED to meet this requirement so they will be able to upgrade to the future platform release where this might become REQUIRED. - SHOULD implement the
TYPE_SIGNIFICANT_MOTION
,TYPE_TILT_DETECTOR
,TYPE_STEP_DETECTOR
,TYPE_STEP_COUNTER
composite sensors as described in the Android SDK document. - SHOULD report events up to at least 200 Hz.
- SHOULD have a resolution of at least 16-bits.
- SHOULD be calibrated while in use if the characteristics changes over the life cycle and compensated, and preserve the compensation parameters between device reboots.
- SHOULD be temperature compensated.
If device implementations include a 3-axis accelerometer and any of the TYPE_SIGNIFICANT_MOTION
, TYPE_TILT_DETECTOR
, TYPE_STEP_DETECTOR
, TYPE_STEP_COUNTER
composite sensors are implemented:
- [C-2-1] The sum of their power consumption MUST always be less than 4 mW.
- SHOULD each be below 2 mW and 0.5 mW for when the device is in a dynamic or static condition.
If device implementations include a 3-axis accelerometer and a 3-axis gyroscope sensor, they:
- [C-3-1] MUST implement the
TYPE_GRAVITY
andTYPE_LINEAR_ACCELERATION
composite sensors. - [C-SR-4] Are STRONGLY RECOMMENDED to implement the
TYPE_GAME_ROTATION_VECTOR
composite sensor.
If device implementations include a 3-axis accelerometer, a 3-axis gyroscope sensor, and a magnetometer sensor, they:
- [C-4-1] MUST implement a
TYPE_ROTATION_VECTOR
composite sensor.
7.3.2. مغناطیس سنج
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to include a 3-axis magnetometer (compass).
If device implementations include a 3-axis magnetometer, they:
- [C-1-1] MUST implement the
TYPE_MAGNETIC_FIELD
sensor. - [C-1-2] MUST be able to report events up to a frequency of at least 10 Hz and SHOULD report events up to at least 50 Hz.
- [C-1-3] MUST comply with the Android sensor coordinate system as detailed in the Android APIs.
- [C-1-4] MUST be capable of measuring between -900 µT and +900 µT on each axis before saturating.
- [C-1-5] MUST have a hard iron offset value less than 700 µT and SHOULD have a value below 200 µT, by placing the magnetometer far from dynamic (current-induced) and static (magnet-induced) magnetic fields.
- [C-1-6] MUST have a resolution equal or denser than 0.6 µT.
- [C-1-7] MUST support online calibration and compensation of the hard iron bias, and preserve the compensation parameters between device reboots.
- [C-1-8] MUST have the soft iron compensation applied—the calibration can be done either while in use or during the production of the device.
- [C-1-9] MUST have a standard deviation, calculated on a per axis basis on samples collected over a period of at least 3 seconds at the fastest sampling rate, no greater than 1.5 µT; SHOULD have a standard deviation no greater than 0.5 µT.
- [C-1-10] MUST implement the
TYPE_MAGNETIC_FIELD_UNCALIBRATED
sensor.
If device implementations include a 3-axis magnetometer, an accelerometer sensor, and a 3-axis gyroscope sensor, they:
- [C-2-1] MUST implement a
TYPE_ROTATION_VECTOR
composite sensor.
If device implementations include a 3-axis magnetometer, an accelerometer, they:
- MAY implement the
TYPE_GEOMAGNETIC_ROTATION_VECTOR
sensor.
If device implementations include a 3-axis magnetometer, an accelerometer and TYPE_GEOMAGNETIC_ROTATION_VECTOR
sensor, they:
- [C-3-1] MUST consume less than 10 mW.
- SHOULD consume less than 3 mW when the sensor is registered for batch mode at 10 Hz.
7.3.3. جی پی اس
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to include a GPS/GNSS receiver.
If device implementations include a GPS/GNSS receiver and report the capability to applications through the android.hardware.location.gps
feature flag, they:
- [C-1-1] MUST support location outputs at a rate of at least 1 Hz when requested via
LocationManager#requestLocationUpdate
. - [C-1-2] MUST be able to determine the location in open-sky conditions (strong signals, negligible multipath, HDOP < 2) within 10 seconds (fast time to first fix), when connected to a 0.5 Mbps or faster data speed internet connection. This requirement is typically met by the use of some form of Assisted or Predicted GPS/GNSS technique to minimize GPS/GNSS lock-on time (Assistance data includes Reference Time, Reference Location and Satellite Ephemeris/Clock).
- [C-1-6] After making such a location calculation, device implementations MUST determine its location, in open sky, within 5 seconds, when location requests are restarted, up to an hour after the initial location calculation, even when the subsequent request is made without a data connection, and/or after a power cycle.
In open sky conditions after determining the location, while stationary or moving with less than 1 meter per second squared of acceleration:
- [C-1-3] MUST be able to determine location within 20 meters, and speed within 0.5 meters per second, at least 95% of the time.
- [C-1-4] MUST simultaneously track and report via
GnssStatus.Callback
at least 8 satellites from one constellation. - SHOULD be able to simultaneously track at least 24 satellites, from multiple constellations (eg GPS + at least one of Glonass, Beidou, Galileo).
[C-SR-2] Are STRONGLY RECOMMENDED to continue to deliver normal GPS/GNSS location outputs through GNSS Location Provider API's during an emergency phone call.
[C-SR-3] Are STRONGLY RECOMMENDED to report GNSS measurements from all constellations tracked (as reported in GnssStatus messages), with the exception of SBAS.
[C-SR-4] Are STRONGLY RECOMMENDED to report AGC, and Frequency of GNSS measurement.
[C-SR-5] Are STRONGLY RECOMMENDED to report all accuracy estimates (including Bearing, Speed, and Vertical) as part of each GPS/GNSS location.
[C-SR-6] Are STRONGLY RECOMMENDED to report GNSS measurements, as soon as they are found, even if a location calculated from GPS/GNSS is not yet reported.
[C-SR-7] Are STRONGLY RECOMMENDED to report GNSS pseudoranges and pseudorange rates, that, in open-sky conditions after determining the location, while stationary or moving with less than 0.2 meter per second squared of acceleration, are sufficient to calculate position within 20 meters, and speed within 0.2 meters per second, at least 95% of the time.
7.3.4. ژیروسکوپ
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to include a gyroscope sensor.
If device implementations include a 3-axis gyroscope, they:
- [C-1-1] MUST be able to report events up to a frequency of at least 50 Hz.
- [C-1-2] MUST implement the
TYPE_GYROSCOPE
sensor. - [C-1-4] MUST have a resolution of 12-bits or more.
- [C-1-5] MUST be temperature compensated.
- [C-1-6] MUST be calibrated and compensated while in use, and preserve the compensation parameters between device reboots.
- [C-1-7] MUST have a variance no greater than 1e-7 rad^2 / s^2 per Hz (variance per Hz, or rad^2 / s). The variance is allowed to vary with the sampling rate, but MUST be constrained by this value. In other words, if you measure the variance of the gyro at 1 Hz sampling rate it SHOULD be no greater than 1e-7 rad^2/s^2.
- [C-SR-2] Calibration error is STRONGLY RECOMMENDED to be less than 0.01 rad/s when device is stationary at room temperature.
- [C-SR-3] Are STRONGLY RECOMMENDED to implement
TYPE_GYROSCOPE_UNCALIBRATED
sensor. - [C-SR-4] Are STRONGLY RECOMMENDED to have a resolution of 16-bits or more.
- SHOULD report events up to at least 200 Hz.
If device implementations include a 3-axis gyroscope, an accelerometer sensor and a magnetometer sensor, they:
- [C-2-1] MUST implement a
TYPE_ROTATION_VECTOR
composite sensor.
If device implementations include a 3-axis accelerometer and a 3-axis gyroscope sensor, they:
- [C-3-1] MUST implement the
TYPE_GRAVITY
andTYPE_LINEAR_ACCELERATION
composite sensors. - [C-SR-5] Are STRONGLY RECOMMENDED to implement the
TYPE_GAME_ROTATION_VECTOR
composite sensor.
7.3.5. فشارسنج
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to include a barometer (ambient air pressure sensor).
If device implementations include a barometer, they:
- [C-1-1] MUST implement and report
TYPE_PRESSURE
sensor. - [C-1-2] MUST be able to deliver events at 5 Hz or greater.
- [C-1-3] MUST be temperature compensated.
- [C-SR-2] STRONGLY RECOMMENDED to be able to report pressure measurements in the range 300hPa to 1100hPa.
- SHOULD have an absolute accuracy of 1hPa.
- SHOULD have a relative accuracy of 0.12hPa over 20hPa range (equivalent to ~1m accuracy over ~200m change at sea level).
7.3.6. دماسنج
If device implementations include an ambient thermometer (temperature sensor), they:
- [C-1-1] MUST define
SENSOR_TYPE_AMBIENT_TEMPERATURE
for the ambient temperature sensor and the sensor MUST measure the ambient (room/vehicle cabin) temperature from where the user is interacting with the device in degrees Celsius.
If device implementations include a thermometer sensor that measures a temperature other than ambient temperature, such as CPU temperature, they:
- [C-2-1] MUST NOT define
SENSOR_TYPE_AMBIENT_TEMPERATURE
for the temperature sensor.
If device implementations include a sensor for monitoring skin temperature, then they:
- [C-SR-1] Are STRONGLY RECOMMENDED to support the PowerManager.getThermalHeadroom API.
7.3.7. فتومتر
- Device implementations MAY include a photometer (ambient light sensor).
7.3.8. Proximity Sensor
- Device implementations MAY include a proximity sensor.
If device implementations include a proximity sensor and they report only a binary “near” or “far” reading, they:
- [C-1-1] MUST measure the proximity of an object in the same direction as the screen. That is, the proximity sensor MUST be oriented to detect objects close to the screen, as the primary intent of this sensor type is to detect a phone in use by the user. If device implementations include a proximity sensor with any other orientation, it MUST NOT be accessible through this API.
- [C-1-2] MUST have 1-bit of accuracy or more.
- [C-1-3] MUST use 0 centimeters as the near reading and 5 centimeters as the far reading.
- [C-1-4] MUST report a maximum range and resolution of 5.
7.3.9. High Fidelity Sensors
If device implementations include a set of higher quality sensors as defined in this section, and make available them to third-party apps, they:
- [C-1-1] MUST identify the capability through the
android.hardware.sensor.hifi_sensors
feature flag.
If device implementations declare android.hardware.sensor.hifi_sensors
, they:
[C-2-1] MUST have a
TYPE_ACCELEROMETER
sensor which:- MUST have a measurement range between at least -8g and +8g, and is STRONGLY RECOMMENDED to have a measurement range between at least -16g and +16g.
- MUST have a measurement resolution of at least 2048 LSB/g.
- MUST have a minimum measurement frequency of 12.5 Hz or lower.
- MUST have a maximum measurement frequency of 400 Hz or higher; SHOULD support the SensorDirectChannel
RATE_VERY_FAST
. - MUST have a measurement noise not above 400 μg/√Hz.
- MUST implement a non-wake-up form of this sensor with a buffering capability of at least 3000 sensor events.
- MUST have a batching power consumption not worse than 3 mW.
- [C-SR-1] Is STRONGLY RECOMMENDED to have 3dB measurement bandwidth of at least 80% of Nyquist frequency, and white noise spectrum within this bandwidth.
- SHOULD have an acceleration random walk less than 30 μg √Hz tested at room temperature.
- SHOULD have a bias change vs. temperature of ≤ +/- 1 mg/°C.
- SHOULD have a best-fit line non-linearity of ≤ 0.5%, and sensitivity change vs. temperature of ≤ 0.03%/C°.
- SHOULD have cross-axis sensitivity of < 2.5 % and variation of cross-axis sensitivity < 0.2% in device operation temperature range.
[C-2-2] MUST have a
TYPE_ACCELEROMETER_UNCALIBRATED
with the same quality requirements asTYPE_ACCELEROMETER
.[C-2-3] MUST have a
TYPE_GYROSCOPE
sensor which:- MUST have a measurement range between at least -1000 and +1000 dps.
- MUST have a measurement resolution of at least 16 LSB/dps.
- MUST have a minimum measurement frequency of 12.5 Hz or lower.
- MUST have a maximum measurement frequency of 400 Hz or higher; SHOULD support the SensorDirectChannel
RATE_VERY_FAST
. - MUST have a measurement noise not above 0.014°/s/√Hz.
- [C-SR-2] Is STRONGLY RECOMMENDED to have 3dB measurement bandwidth of at least 80% of Nyquist frequency, and white noise spectrum within this bandwidth.
- SHOULD have a rate random walk less than 0.001 °/s √Hz tested at room temperature.
- SHOULD have a bias change vs. temperature of ≤ +/- 0.05 °/ s / °C.
- SHOULD have a sensitivity change vs. temperature of ≤ 0.02% / °C.
- SHOULD have a best-fit line non-linearity of ≤ 0.2%.
- SHOULD have a noise density of ≤ 0.007 °/s/√Hz.
- SHOULD have calibration error less than 0.002 rad/s in temperature range 10 ~ 40 ℃ when device is stationary.
- SHOULD have g-sensitivity less than 0.1°/s/g.
- SHOULD have cross-axis sensitivity of < 4.0 % and cross-axis sensitivity variation < 0.3% in device operation temperature range.
[C-2-4] MUST have a
TYPE_GYROSCOPE_UNCALIBRATED
with the same quality requirements asTYPE_GYROSCOPE
.[C-2-5] MUST have a
TYPE_GEOMAGNETIC_FIELD
sensor which:- MUST have a measurement range between at least -900 and +900 μT.
- MUST have a measurement resolution of at least 5 LSB/uT.
- MUST have a minimum measurement frequency of 5 Hz or lower.
- MUST have a maximum measurement frequency of 50 Hz or higher.
- MUST have a measurement noise not above 0.5 uT.
[C-2-6] MUST have a
TYPE_MAGNETIC_FIELD_UNCALIBRATED
with the same quality requirements asTYPE_GEOMAGNETIC_FIELD
and in addition:- MUST implement a non-wake-up form of this sensor with a buffering capability of at least 600 sensor events.
- [C-SR-3] Is STRONGLY RECOMMENDED to have white noise spectrum from 1 Hz to at least 10 Hz when the report rate is 50 Hz or higher.
[C-2-7] MUST have a
TYPE_PRESSURE
sensor which:- MUST have a measurement range between at least 300 and 1100 hPa.
- MUST have a measurement resolution of at least 80 LSB/hPa.
- MUST have a minimum measurement frequency of 1 Hz or lower.
- MUST have a maximum measurement frequency of 10 Hz or higher.
- MUST have a measurement noise not above 2 Pa/√Hz.
- MUST implement a non-wake-up form of this sensor with a buffering capability of at least 300 sensor events.
- MUST have a batching power consumption not worse than 2 mW.
[C-2-8] MUST have a
TYPE_GAME_ROTATION_VECTOR
sensor.[C-2-9] MUST have a
TYPE_SIGNIFICANT_MOTION
sensor which:- MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
[C-2-10] MUST have a
TYPE_STEP_DETECTOR
sensor which:- MUST implement a non-wake-up form of this sensor with a buffering capability of at least 100 sensor events.
- MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
- MUST have a batching power consumption not worse than 4 mW.
[C-2-11] MUST have a
TYPE_STEP_COUNTER
sensor which:- MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
[C-2-12] MUST have a
TILT_DETECTOR
sensor which:- MUST have a power consumption not worse than 0.5 mW when device is static and 1.5 mW when device is moving.
[C-2-13] The event timestamp of the same physical event reported by the Accelerometer, Gyroscope, and Magnetometer MUST be within 2.5 milliseconds of each other. The event timestamp of the same physical event reported by the Accelerometer and Gyroscope SHOULD be within 0.25 milliseconds of each other.
[C-2-14] MUST have Gyroscope sensor event timestamps on the same time base as the camera subsystem and within 1 milliseconds of error.
[C-2-15] MUST deliver samples to applications within 5 milliseconds from the time when the data is available on any of the above physical sensors to the application.
[C-2-16] MUST NOT have a power consumption higher than 0.5 mW when device is static and 2.0 mW when device is moving when any combination of the following sensors are enabled:
-
SENSOR_TYPE_SIGNIFICANT_MOTION
-
SENSOR_TYPE_STEP_DETECTOR
-
SENSOR_TYPE_STEP_COUNTER
-
SENSOR_TILT_DETECTORS
-
[C-2-17] MAY have a
TYPE_PROXIMITY
sensor, but if present MUST have a minimum buffer capability of 100 sensor events.
Note that all power consumption requirements in this section do not include the power consumption of the Application Processor. It is inclusive of the power drawn by the entire sensor chain—the sensor, any supporting circuitry, any dedicated sensor processing system, etc.
If device implementations include direct sensor support, they:
- [C-3-1] MUST correctly declare support of direct channel types and direct report rates level through the
isDirectChannelTypeSupported
andgetHighestDirectReportRateLevel
API. - [C-3-2] MUST support at least one of the two sensor direct channel types for all sensors that declare support for sensor direct channel.
- SHOULD support event reporting through sensor direct channel for primary sensor (non-wakeup variant) of the following types:
-
TYPE_ACCELEROMETER
-
TYPE_ACCELEROMETER_UNCALIBRATED
-
TYPE_GYROSCOPE
-
TYPE_GYROSCOPE_UNCALIBRATED
-
TYPE_MAGNETIC_FIELD
-
TYPE_MAGNETIC_FIELD_UNCALIBRATED
-
7.3.10. Biometric Sensors
For additional background on Measuring Biometric Unlock Security, please see Measuring Biometric Security documentation .
If device implementations include a secure lock screen, they:
- SHOULD include a biometric sensor
Biometric sensors can be classified as Class 3 (formerly Strong ), Class 2 (formerly Weak ), or Class 1 (formerly Convenience ) based on their spoof and imposter acceptance rates, and on the security of the biometric pipeline. This classification determines the capabilities the biometric sensor has to interface with the platform and with third-party applications. Sensors are classified as Class 1 by default, and need to meet additional requirements as detailed below if they wish to be classified as either Class 2 or Class 3 . Both Class 2 and Class 3 biometrics get additional capabilities as detailed below.
If device implementations make a biometric sensor available to third-party applications via android.hardware.biometrics.BiometricManager , android.hardware.biometrics.BiometricPrompt , and android.provider.Settings.ACTION_BIOMETRIC_ENROLL , they:
- [C-4-1] MUST meet the requirements for Class 3 or Class 2 biometric as defined in this document.
- [C-4-2] MUST recognize and honor each parameter name defined as a constant in the Authenticators class and any combinations thereof. Conversely, MUST NOT honor or recognize integer constants passed to the canAuthenticate(int) and setAllowedAuthenticators(int) methods other than those documented as public constants in Authenticators and any combinations thereof.
- [C-4-3] MUST implement the ACTION_BIOMETRIC_ENROLL action on devices that have either Class 3 or Class 2 biometrics. This action MUST only present the enrollment entry points for Class 3 or Class 2 biometrics.
If device implementations support passive biometrics, they:
- [C-5-1] MUST by default require an additional confirmation step (eg a button press).
- [C-SR-1] Are STRONGLY RECOMMENDED to have a setting to allow users to override application preference and always require accompanying confirmation step.
- [C-SR-2] Are STRONGLY RECOMMENDED to have the confirm action be secured such that an operating system or kernel compromise cannot spoof it. For example, this means that the confirm action based on a physical button is routed through an input-only general-purpose input/output (GPIO) pin of a secure element (SE) that cannot be driven by any other means than a physical button را فشار دهید.
- [C-5-2] MUST additionally implement an implicit authentication flow (without confirmation step) corresponding to setConfirmationRequired(boolean) , which applications can set to utilize for sign-in flows.
If device implementations have multiple biometric sensors, they:
- [C-SR-3] Are STRONGLY RECOMMENDED to require only one biometric be confirmed per authentication (eg if both fingerprint and face sensors are available on the device, onAuthenticationSucceeded should be sent after any one of them is confirmed).
In order for device implementations to allow access to keystore keys to third-party applications, they:
- [C-6-1] MUST meet the requirements for Class 3 as defined in this section below.
- [C-6-2] MUST present only Class 3 biometrics when the authentication requires BIOMETRIC_STRONG , or the authentication is invoked with a CryptoObject .
If device implementations wish to treat a biometric sensor as Class 1 (formerly Convenience ), they:
- [C-1-1] MUST have a false acceptance rate less than 0.002%.
- [C-1-2] MUST disclose that this mode may be less secure than a strong PIN, pattern, or password and clearly enumerate the risks of enabling it, if the spoof and imposter acceptance rates are higher than 7% as measured by the Android Biometrics Test Protocols .
- [C-1-9] MUST challenge the user for the recommended primary authentication (eg PIN, pattern, password) after no more than twenty false trials and no less than ninety-second backoff time for biometric verification - where a false trial is one with an adequate capture quality (BIOMETRIC_ACQUIRED_GOOD) that does not match an enrolled biometric.
- [C-SR-4] Are STRONGLY RECOMMENDED to lower the total number of false trials for biometric verification specified in [C-1-9] if the spoof and imposter acceptance rates are higher than 7% as measure by the Android Biometrics Test Protocols .
- [C-1-3] MUST rate limit attempts for biometric verification - where a false trial is one with an adequate capture quality (
BIOMETRIC_ACQUIRED_GOOD
) that does not match an enrolled biometric. - [C-SR-5] Are STRONGLY RECOMMENDED to rate limit attempts for at least 30 seconds after five false trials for biometric verification for the maximum number of false trials per [C-1-9] - where a false trial is one with an adequate capture quality (BIOMETRIC_ACQUIRED_GOOD) that does not match an enrolled biometric.
- [C-SR-6] Are STRONGLY RECOMMENDED to have all rate limiting logic in TEE.
- [C-1-10] MUST disable biometrics once primary authentication backoff has first triggered as described in [C-0-2] of section 9.11.
- [C-1-4] MUST prevent adding new biometrics without first establishing a chain of trust by having the user confirm existing or add a new device credential (PIN/pattern/password) that's secured by TEE; the Android Open Source Project implementation provides the mechanism in the framework to do so.
- [C-1-5] MUST completely remove all identifiable biometric data for a user when the user's account is removed (including via a factory reset).
- [C-1-6] MUST honor the individual flag for that biometric (ie
DevicePolicyManager.KEYGUARD_DISABLE_FINGERPRINT
,DevicePolicymanager.KEYGUARD_DISABLE_FACE
, orDevicePolicymanager.KEYGUARD_DISABLE_IRIS
). - [C-1-7] MUST challenge the user for the recommended primary authentication (eg PIN, pattern, password): a) once every 24 hours or less for devices launching with Android version 9 or later, or b) once every 72 hours or less for devices upgrading from Android 8 or earlier.
[C-1-8] MUST challenge the user for the recommended primary authentication (eg: PIN, pattern, password) or Class 3 (STRONG) biometric after one of the following:
- a 4-hour idle timeout period, OR
3 failed biometric authentication attempts.
[C-SR-7] Are STRONGLY RECOMMENDED to use the logic in the framework provided by the Android Open Source Project to enforce constraints specified in [C-1-7] and [C-1-8] for new devices.
[C-SR-8] Are STRONGLY RECOMMENDED to have a false rejection rate of less than 10%, as measured on the device.
[C-SR-9] Are STRONGLY RECOMMENDED to have a latency below 1 second, measured from when the biometric is detected, until the screen is unlocked, for each enrolled biometric.
If device implementations wish to treat a biometric sensor as Class 2 (formerly Weak ), they:
- [C-2-1] MUST meet all requirements for Class 1 above.
- [C-2-2] MUST have a spoof and imposter acceptance rate not higher than 20% as measured by the Android Biometrics Test Protocols .
- [C-2-3] MUST perform the biometric matching in an isolated execution environment outside Android user or kernel space, such as the Trusted Execution Environment (TEE), or on a chip with a secure channel to the isolated execution environment.
- [C-2-4] MUST have all identifiable data encrypted and cryptographically authenticated such that they cannot be acquired, read or altered outside of the isolated execution environment or a chip with a secure channel to the isolated execution environment as documented in the implementation guidelines on the Android Open Source Project site.
- [C-2-5] For camera based biometrics, while biometric based authentication or enrollment is happening:
- MUST operate the camera in a mode that prevents camera frames from being read or altered outside the isolated execution environment or a chip with a secure channel to the isolated execution environment.
- For RGB single-camera solutions, the camera frames CAN be readable outside the isolated execution environment to support operations such as preview for enrollment, but MUST still NOT be alterable.
- [C-2-6] MUST NOT enable third-party applications to distinguish between individual biometric enrollments.
- [C-2-7] MUST NOT allow unencrypted access to identifiable biometric data or any data derived from it (such as embeddings) to the Application Processor outside the context of the TEE. Upgrading devices launched on Android version 9 or earlier are not exempted from C-2-7.
[C-2-8] MUST have a secure processing pipeline such that an operating system or kernel compromise cannot allow data to be directly injected to falsely authenticate as the user.
[C-SR-10] Are STRONGLY RECOMMENDED to include liveness detection for all biometric modalities and attention detection for Face biometrics.
[C-2-9] MUST make the biometric sensor available to third-party applications.
If device implementations wish to treat a biometric sensor as Class 3 (formerly Strong ), they:
- [C-3-1] MUST meet all the requirements of Class 2 above, except for [C-1-7] and [C-1-8].
- [C-3-2] MUST have a hardware-backed keystore implementation.
- [C-3-3] MUST have a spoof and imposter acceptance rate not higher than 7% as measured by the Android Biometrics Test Protocols .
- [C-3-4] MUST challenge the user for the recommended primary authentication (eg PIN, pattern, password) once every 72 hours or less.
- [C-3-5] MUST re-generate Authenticator ID for all Class 3 biometrics supported on device if any of them is re-enrolled.
- [C-3-6] Must enable biometric-backed keystore keys to third-party applications.
If device implementations contain an under-display fingerprint sensor (UDFPS), they:
- [C-SR-11] Are STRONGLY RECOMMENDED to prevent the touchable area of the UDFPS from interfering with 3-button navigation( which some users might require for accessibility purposes).
7.3.12. Pose Sensor
Device implementations:
- MAY support pose sensor with 6 degrees of freedom.
If device implementations support pose sensor with 6 degrees of freedom, they:
- [C-1-1] MUST implement and report
TYPE_POSE_6DOF
sensor. - [C-1-2] MUST be more accurate than the rotation vector alone.
7.3.13. Hinge Angle Sensor
If device implementations support a hinge angle sensor, they:
- [C-1-1] MUST implement and report
TYPE_HINGLE_ANGLE
. - [C-1-2] MUST support at least two readings between 0 and 360 degrees (inclusive ie including 0 and 360 degrees).
- [C-1-3] MUST return a wakeup sensor for
getDefaultSensor(SENSOR_TYPE_HINGE_ANGLE)
.
7.4. Data Connectivity
7.4.1. تلفن
“Telephony” as used by the Android APIs and this document refers specifically to hardware related to placing voice calls and sending SMS messages via a GSM or CDMA network. While these voice calls may or may not be packet-switched, they are for the purposes of Android considered independent of any data connectivity that may be implemented using the same network. In other words, the Android “telephony” functionality and APIs refer specifically to voice calls and SMS. For instance, device implementations that cannot place calls or send/receive SMS messages are not considered a telephony device, regardless of whether they use a cellular network for data connectivity.
- Android MAY be used on devices that do not include telephony hardware. That is, Android is compatible with devices that are not phones.
If device implementations include GSM or CDMA telephony, they:
- [C-1-1] MUST declare the
android.hardware.telephony
feature flag and other sub-feature flags according to the technology. - [C-1-2] MUST implement full support for the API for that technology.
- SHOULD allow all available cellular service types (2G, 3G, 4G, 5G, etc.) during emergency calls (regardless of the network types set by
SetAllowedNetworkTypeBitmap()
).
If device implementations do not include telephony hardware, they:
- [C-2-1] MUST implement the full APIs as no-ops.
If device implementations support eUICCs or eSIMs/embedded SIMs and include a proprietary mechanism to make eSIM functionality available for third-party developers, they:
- [C-3-1] MUST provide a complete implementation of the
EuiccManager API
.
If device implementations don't set the system property ro.telephony.iwlan\_operation\_mode
to 'legacy', then they:
- [C-4-1] MUST NOT report ' NETWORK_TYPE_IWLAN ' via NetworkRegistrationInfo#getAccessNetworkTechnology() when NetworkRegistrationInfo#getTransportType() is reported as ' TRANSPORT_TYPE_WWAN ' for the same NetworkRegistrationInfo instance.
If device implementations support a single IP Multimedia Subsystem (IMS) registration for both multimedia telephony service (MMTEL) and rich communication service (RCS) features and are expected to comply with cellular carrier requirements regarding using a single IMS registration for all IMS signalling traffic, آنها:
- [C-5-1] MUST declare the
android.hardware.telephony.ims
feature flag and provide a complete implementation of the ImsService API for both MMTEL and RCS User Capability Exchange API . - [C-5-2] MUST declare the
android.hardware.telephony.ims.singlereg
feature flag and provide a complete implementation of the SipTransport API , the GbaService API , dedicated bearer indications using the IRadio 1.6 HAL, and provisioning via Auto Configuration Server (ACS) or other proprietary provisioning mechanism using the IMS Configuration API .
7.4.1.1. Number Blocking Compatibility
If device implementations report the android.hardware.telephony feature
, they:
- [C-1-1] MUST include number blocking support
- [C-1-2] MUST fully implement
BlockedNumberContract
and the corresponding API as described in the SDK documentation. - [C-1-3] MUST block all calls and messages from a phone number in 'BlockedNumberProvider' without any interaction with apps. The only exception is when number blocking is temporarily lifted as described in the SDK documentation.
- [C-1-4] MUST NOT write to the platform call log provider for a blocked call.
- [C-1-5] MUST NOT write to the Telephony provider for a blocked message.
- [C-1-6] MUST implement a blocked numbers management UI, which is opened with the intent returned by
TelecomManager.createManageBlockedNumbersIntent()
method. - [C-1-7] MUST NOT allow secondary users to view or edit the blocked numbers on the device as the Android platform assumes the primary user to have full control of the telephony services, a single instance, on the device. All blocking related UI MUST be hidden for secondary users and the blocked list MUST still be respected.
- SHOULD migrate the blocked numbers into the provider when a device updates to Android 7.0.
7.4.1.2. Telecom API
If device implementations report android.hardware.telephony
, they:
- [C-1-1] MUST support the
ConnectionService
APIs described in the SDK . - [C-1-2] MUST display a new incoming call and provide user affordance to accept or reject the incoming call when the user is on an ongoing call that is made by a third-party app that does not support the hold feature specified via
CAPABILITY_SUPPORT_HOLD
. - [C-1-3] MUST have an application that implements InCallService .
[C-SR-1] Are STRONGLY RECOMMENDED to notify the user that answering an incoming call will drop an ongoing call.
The AOSP implementation meets these requirements by a heads-up notification which indicates to the user that answering an incoming call will cause the other call to be dropped.
[C-SR-1] Are STRONGLY RECOMMENDED to preload the default dialer app that shows a call log entry and the name of a third-party app in its call log when the third-party app sets the
EXTRA_LOG_SELF_MANAGED_CALLS
extras key on itsPhoneAccount
totrue
.[C-SR-2] Are STRONGLY RECOMMENDED to handle the audio headset's
KEYCODE_MEDIA_PLAY_PAUSE
andKEYCODE_HEADSETHOOK
events for theandroid.telecom
APIs as below:- Call
Connection.onDisconnect()
when a short press of the key event is detected during an ongoing call. - Call
Connection.onAnswer()
when a short press of the key event is detected during an incoming call. - Call
Connection.onReject()
when a long press of the key event is detected during an incoming call. - Toggle the mute status of the
CallAudioState
.
- Call
7.4.2. IEEE 802.11 (Wi-Fi)
Device implementations:
- SHOULD include support for one or more forms of 802.11.
If device implementations include support for 802.11 and expose the functionality to a third-party application, they:
- [C-1-1] MUST implement the corresponding Android API.
- [C-1-2] MUST report the hardware feature flag
android.hardware.wifi
. - [C-1-3] MUST implement the multicast API as described in the SDK documentation.
- [C-1-4] MUST support multicast DNS (mDNS) and MUST NOT filter mDNS packets (224.0.0.251) at any time of operation including:
- Even when the screen is not in an active state.
- For Android Television device implementations, even when in standby power states.
- [C-1-5] MUST NOT treat the
WifiManager.enableNetwork()
API method call as a sufficient indication to switch the currently activeNetwork
that is used by default for application traffic and is returned byConnectivityManager
API methods such asgetActiveNetwork
andregisterDefaultNetworkCallback
. In other words, they MAY only disable the Internet access provided by any other network provider (eg mobile data) if they successfully validate that the Wi-Fi network is providing Internet access. - [C-1-6] Are STRONGLY RECOMMENDED to, when the
ConnectivityManager.reportNetworkConnectivity()
API method is called, re-evaluate the Internet access on theNetwork
and, once the evaluation determines that the currentNetwork
no longer provides Internet access, switch to any other available network (eg mobile data) that provides Internet access. - [C-1-7] MUST randomize the source MAC address and sequence number of probe request frames, once at the beginning of each scan, while STA is disconnected.
- [C-1-8] MUST use one consistent MAC address (SHOULD NOT randomize MAC address halfway through a scan).
- [C-1-9] MUST iterate probe request sequence number as normal (sequentially) between the probe requests in a scan.
- [C-1-10] MUST randomize Probe request sequence number between the last probe request of a scan and the first probe request of the next scan.
- [C-SR-1] Are STRONGLY RECOMMENDED to randomize the source MAC address used for all STA communication to an Access Point (AP) while associating and associated.
- The device MUST use a different randomized MAC address for each SSID (FQDN for Passpoint) it communicates with.
- The device MUST provide the user with an option to control the randomization per SSID (FQDN for Passpoint) with non randomized and randomized options, and MUST set the default mode for new Wi-Fi configurations to be randomized.
- [C-SR-2] Are STRONGLY RECOMMENDED to use a random BSSID for any AP that they create.
- The MAC address MUST be randomized and persisted per SSID used by the AP.
- The DEVICE MAY provide the user with an option to disable this feature. If such an option is provided, randomization MUST be enabled by default.
If device implementations include support for Wi-Fi power save mode as defined in IEEE 802.11 standard, they:
- SHOULD turn off Wi-Fi power save mode whenever an app acquires
WIFI_MODE_FULL_HIGH_PERF
lock orWIFI_MODE_FULL_LOW_LATENCY
lock viaWifiManager.createWifiLock()
andWifiManager.WifiLock.acquire()
APIs and the lock is active. - [C-3-2] The average round trip latency between the device and an access point while the device is in a Wi-Fi Low Latency Lock (
WIFI_MODE_FULL_LOW_LATENCY
) mode MUST be smaller than the latency during a Wi-Fi High Perf Lock (WIFI_MODE_FULL_HIGH_PERF
) mode. - [C-SR-3] Are STRONGLY RECOMMENDED to minimize Wi-Fi round trip latency whenever a Low Latency Lock (
WIFI_MODE_FULL_LOW_LATENCY
) is acquired and takes effect.
If device implementations support Wi-Fi and use Wi-Fi for location scanning, they:
- [C-2-1] MUST provide a user affordance to enable/disable the value read through the
WifiManager.isScanAlwaysAvailable
API method.
7.4.2.1. وای فای دایرکت
Device implementations:
- SHOULD include support for Wi-Fi Direct (Wi-Fi peer-to-peer).
If device implementations include support for Wi-Fi Direct, they:
- [C-1-1] MUST implement the corresponding Android API as described in the SDK documentation.
- [C-1-2] MUST report the hardware feature
android.hardware.wifi.direct
. - [C-1-3] MUST support regular Wi-Fi operation.
- [C-1-4] MUST support Wi-Fi and Wi-Fi Direct operations concurrently.
- [C-SR-1] Are STRONGLY RECOMMENDED to randomize the source MAC address for all newly formed Wi-Fi Direct connections.
7.4.2.2. Wi-Fi Tunneled Direct Link Setup
Device implementations:
- SHOULD include support for Wi-Fi Tunneled Direct Link Setup (TDLS) as described in the Android SDK Documentation.
If device implementations include support for TDLS and TDLS is enabled by the WiFiManager API, they:
- [C-1-1] MUST declare support for TDLS through
WifiManager.isTdlsSupported
. - SHOULD use TDLS only when it is possible AND beneficial.
- SHOULD have some heuristic and NOT use TDLS when its performance might be worse than going through the Wi-Fi access point.
7.4.2.3. Wi-Fi Aware
Device implementations:
- SHOULD include support for Wi-Fi Aware .
If device implementations include support for Wi-Fi Aware and expose the functionality to third-party apps, then they:
- [C-1-1] MUST implement the
WifiAwareManager
APIs as described in the SDK documentation . - [C-1-2] MUST declare the
android.hardware.wifi.aware
feature flag. - [C-1-3] MUST support Wi-Fi and Wi-Fi Aware operations concurrently.
- [C-1-4] MUST randomize the Wi-Fi Aware management interface address at intervals no longer than 30 minutes and whenever Wi-Fi Aware is enabled unless an Aware ranging operation is ongoing or an Aware data-path is active (randomization is not expected for as long as the data-path is active).
If device implementations include support for Wi-Fi Aware and Wi-Fi Location as described in Section 7.4.2.5 and exposes these functionalities to third-party apps, then they:
- [C-2-1] MUST implement the location-aware discovery APIs: setRangingEnabled , setMinDistanceMm , setMaxDistanceMm , and onServiceDiscoveredWithinRange .
7.4.2.4. Wi-Fi Passpoint
If device implementations include support for 802.11 (Wi-Fi) they:
- [C-1-1] MUST include support for Wi-Fi Passpoint .
- [C-1-2] MUST implement the Passpoint related
WifiManager
APIs as described in the SDK documentation . - [C-1-3] MUST support IEEE 802.11u standard, specifically related to Network Discovery and Selection, such as Generic Advertisement Service (GAS) and Access Network Query Protocol (ANQP).
- [C-1-4] MUST declare
android.hardware.wifi.passpoint
feature flag. - [C-1-5] MUST follow the AOSP implementation to discover, match and associate to Passpoint networks.
- [C-1-6] MUST support at least the following subset of device provisioning protocols as defined in the Wi-Fi Alliance Passpoint R2: EAP-TTLS authentication and SOAP-XML.
- [C-1-7] MUST process the AAA server certificate as described in Hotspot 2.0 R3 specification.
- [C-1-8] MUST support user control of provisioning through the Wi-Fi picker.
- [C-1-9] MUST keep Passpoint configurations persistent across reboots.
- [C-SR-1] Are STRONGLY RECOMMENDED to support the terms and conditions acceptance feature.
- [C-SR-2] Are STRONGLY RECOMMENDED to support the Venue information feature.
Conversely if device implementations do not include support for Wi-Fi Passpoint:
- [C-2-1] The implementation of the Passpoint related
WifiManager
APIs MUST throw anUnsupportedOperationException
.
If a global Passpoint disable user control switch is provided, implementations:
- [C-3-1] MUST enable Passpoint by default.
7.4.2.5. Wi-Fi Location (Wi-Fi Round Trip Time - RTT)
Device implementations:
- SHOULD include support for Wi-Fi Location .
If device implementations include support for Wi-Fi Location and expose the functionality to third-party apps, then they:
- [C-1-1] MUST implement the
WifiRttManager
APIs as described in the SDK documentation . - [C-1-2] MUST declare the
android.hardware.wifi.rtt
feature flag. - [C-1-3] MUST randomize the source MAC address for each RTT burst which is executed while the Wi-Fi interface on which the RTT is being executed is not associated to an Access Point.
- [C-1-4] MUST be accurate to within 2 meters at 80 MHz bandwidth at the 68th percentile (as calculated with the Cumulative Distribution Function).
7.4.2.6. Wi-Fi Keepalive Offload
Device implementations:
- SHOULD include support for Wi-Fi keepalive offload.
If device implementations include support for Wi-Fi keepalive offload and expose the functionality to third-party apps, they:
[C-1-1] MUST support the SocketKeepAlive API.
[C-1-2] MUST support at least three concurrent keepalive slots over Wi-Fi and at least one keepalive slot over cellular.
If device implementations do not include support for Wi-Fi keepalive offload, they:
- [C-2-1] MUST return
ERROR_UNSUPPORTED
.
7.4.2.7. Wi-Fi Easy Connect (Device Provisioning Protocol)
Device implementations:
- SHOULD include support for Wi-Fi Easy Connect (DPP) .
If device implementations include support for Wi-Fi Easy Connect and expose the functionality to third-party apps, they:
- [C-1-1] MUST have the WifiManager#isEasyConnectSupported() method return
true
.
7.4.2.8. Enterprise Wi-Fi Server Certificate Validation
If the Wi-Fi server certificate is not validated or the Wi-Fi server domain name is not set, device implementations:
- [C-SR-1] are STRONGLY RECOMMENDED not to provide the user an option to manually add Enterprise Wi-Fi network in the Settings app.
7.4.3. بلوتوث
If device implementations support Bluetooth Audio profile, they:
- SHOULD support Advanced Audio Codecs and Bluetooth Audio Codecs (eg LDAC).
If device implementations support HFP, A2DP and AVRCP, they:
- SHOULD support at least 5 total connected devices.
If device implementations declare android.hardware.vr.high_performance
feature, they:
- [C-1-1] MUST support Bluetooth 4.2 and Bluetooth LE Data Length Extension.
Android includes support for Bluetooth and Bluetooth Low Energy .
If device implementations include support for Bluetooth and Bluetooth Low Energy, they:
- [C-2-1] MUST declare the relevant platform features (
android.hardware.bluetooth
andandroid.hardware.bluetooth_le
respectively) and implement the platform APIs. - SHOULD implement relevant Bluetooth profiles such as A2DP, AVRCP, OBEX, HFP, etc. as appropriate for the device.
If device implementations include support for Bluetooth Low Energy (BLE), they:
- [C-3-1] MUST declare the hardware feature
android.hardware.bluetooth_le
. - [C-3-2] MUST enable the GATT (generic attribute profile) based Bluetooth APIs as described in the SDK documentation and android.bluetooth .
- [C-3-3] MUST report the correct value for
BluetoothAdapter.isOffloadedFilteringSupported()
to indicate whether the filtering logic for the ScanFilter API classes is implemented. - [C-3-4] MUST report the correct value for
BluetoothAdapter.isMultipleAdvertisementSupported()
to indicate whether Low Energy Advertising is supported. - [C-3-5] MUST implement a Resolvable Private Address (RPA) timeout no longer than 15 minutes and rotate the address at timeout to protect user privacy when device is actively using BLE for scanning or advertising. To prevent timing attacks, timeout intervals MUST also be randomized between 5 and 15 minutes.
- SHOULD support offloading of the filtering logic to the bluetooth chipset when implementing the ScanFilter API .
- SHOULD support offloading of the batched scanning to the bluetooth chipset.
- SHOULD support multi advertisement with at least 4 slots.
If device implementations support Bluetooth LE and use Bluetooth LE for location scanning, they:
- [C-4-1] MUST provide a user affordance to enable/disable the value read through the System API
BluetoothAdapter.isBleScanAlwaysAvailable()
.
If device implementations include support for Bluetooth LE and Hearing Aids Profile, as described in Hearing Aid Audio Support Using Bluetooth LE , they:
- [C-5-1] MUST return
true
for BluetoothAdapter.getProfileProxy(context, listener, BluetoothProfile.HEARING_AID) .
If device implementations include support for Bluetooth or Bluetooth Low Energy, they:
- [C-6-1] MUST restrict access to any Bluetooth metadata (such as scan results) which could be used to derive the location of the device, unless the requesting app successfully passes an
android.permission.ACCESS_FINE_LOCATION
permission check based on its current foreground/background state.
If device implementations include support for Bluetooth or Bluetooth Low Energy and the app manifest does not include a declaration from the developer stating that they are not deriving location from Bluetooth, then, they:
- [C-6-2] MUST gate Bluetooth access behind the
android.permission.ACCESS_FINE_LOCATION
.
7.4.4. Near-Field Communications
Device implementations:
- SHOULD include a transceiver and related hardware for Near-Field Communications (NFC).
- [C-0-1] MUST implement
android.nfc.NdefMessage
andandroid.nfc.NdefRecord
APIs even if they do not include support for NFC or declare theandroid.hardware.nfc
feature as the classes represent a protocol-independent data representation format .
If device implementations include NFC hardware and plan to make it available to third-party apps, they:
- [C-1-1] MUST report the
android.hardware.nfc
feature from theandroid.content.pm.PackageManager.hasSystemFeature()
method . - MUST be capable of reading and writing NDEF messages via the following NFC standards as below:
- [C-1-2] MUST be capable of acting as an NFC Forum reader/writer (as defined by the NFC Forum technical specification NFCForum-TS-DigitalProtocol-1.0) via the following NFC standards:
- NfcA (ISO14443-3A)
- NfcB (ISO14443-3B)
- NfcF (JIS X 6319-4)
- IsoDep (ISO 14443-4)
- NFC Forum Tag Types 1, 2, 3, 4, 5 (defined by the NFC Forum)
[C-SR-1] STRONGLY RECOMMENDED to be capable of reading and writing NDEF messages as well as raw data via the following NFC standards. Note that while the NFC standards are stated as STRONGLY RECOMMENDED, the Compatibility Definition for a future version is planned to change these to MUST. These standards are optional in this version but will be required in future versions. Existing and new devices that run this version of Android are very strongly encouraged to meet these requirements now so they will be able to upgrade to the future platform releases.
[C-1-13] MUST poll for all supported technologies while in NFC discovery mode.
SHOULD be in NFC discovery mode while the device is awake with the screen active and the lock-screen unlocked.
SHOULD be capable of reading the barcode and URL (if encoded) of Thinfilm NFC Barcode products.
Note that publicly available links are not available for the JIS, ISO, and NFC Forum specifications cited above.
Android includes support for NFC Host Card Emulation (HCE) mode.
If device implementations include an NFC controller chipset capable of HCE (for NfcA and/or NfcB) and support Application ID (AID) routing, they:
- [C-2-1] MUST report the
android.hardware.nfc.hce
feature constant. - [C-2-2] MUST support NFC HCE APIs as defined in the Android SDK.
If device implementations include an NFC controller chipset capable of HCE for NfcF, and implement the feature for third-party applications, they:
- [C-3-1] MUST report the
android.hardware.nfc.hcef
feature constant. - [C-3-2] MUST implement the NfcF Card Emulation APIs as defined in the Android SDK.
If device implementations include general NFC support as described in this section and support MIFARE technologies (MIFARE Classic, MIFARE Ultralight, NDEF on MIFARE Classic) in the reader/writer role, they:
- [C-4-1] MUST implement the corresponding Android APIs as documented by the Android SDK.
- [C-4-2] MUST report the feature
com.nxp.mifare
from theandroid.content.pm.PackageManager.hasSystemFeature
() method. Note that this is not a standard Android feature and as such does not appear as a constant in theandroid.content.pm.PackageManager
class.
7.4.5. Networking protocols and APIs
7.4.5.1. Minimum Network Capability
Device implementations:
- [C-0-1] MUST include support for one or more forms of data networking. Specifically, device implementations MUST include support for at least one data standard capable of 200 Kbit/sec or greater. Examples of technologies that satisfy this requirement include EDGE, HSPA, EV-DO, 802.11g, Ethernet and Bluetooth PAN.
- SHOULD also include support for at least one common wireless data standard, such as 802.11 (Wi-Fi), when a physical networking standard (such as Ethernet) is the primary data connection.
- MAY implement more than one form of data connectivity.
7.4.5.2. IPv6
Device implementations:
- [C-0-2] MUST include an IPv6 networking stack and support IPv6 communication using the managed APIs, such as
java.net.Socket
andjava.net.URLConnection
, as well as the native APIs, such asAF_INET6
sockets. - [C-0-3] MUST enable IPv6 by default.
- MUST ensure that IPv6 communication is as reliable as IPv4, for example:
- [C-0-4] MUST maintain IPv6 connectivity in doze mode.
- [C-0-5] Rate-limiting MUST NOT cause the device to lose IPv6 connectivity on any IPv6-compliant network that uses RA lifetimes of at least 180 seconds.
- MUST ensure that IPv6 communication is as reliable as IPv4, for example:
- [C-0-6] MUST provide third-party applications with direct IPv6 connectivity to the network when connected to an IPv6 network, without any form of address or port translation happening locally on the device. Both managed APIs such as
Socket#getLocalAddress
orSocket#getLocalPort
) and NDK APIs such asgetsockname()
orIPV6_PKTINFO
MUST return the IP address and port that is actually used to send and receive packets on the network and is visible as the source ip and port to internet (web) servers.
The required level of IPv6 support depends on the network type, as shown in the following requirements.
If device implementations support Wi-Fi, they:
- [C-1-1] MUST support dual-stack and IPv6-only operation on Wi-Fi.
If device implementations support Ethernet, they:
- [C-2-1] MUST support dual-stack and IPv6-only operation on Ethernet.
If device implementations support Cellular data, they:
- [C-3-1] MUST support IPv6 operation (IPv6-only and possibly dual-stack) on cellular.
If device implementations support more than one network type (eg, Wi-Fi and cellular data), they:
- [C-4-1] MUST simultaneously meet the above requirements on each network when the device is simultaneously connected to more than one network type.
7.4.5.3. Captive Portals
A captive portal refers to a network that requires sign-in in order to obtain internet access.
If device implementations provide a complete implementation of the android.webkit.Webview API
, they:
- [C-1-1] MUST provide a captive portal application to handle the intent
ACTION_CAPTIVE_PORTAL_SIGN_IN
and display the captive portal login page, by sending that intent, on call to the System APIConnectivityManager#startCaptivePortalApp(Network, Bundle)
. - [C-1-2] MUST perform detection of captive portals and support login through the captive portal application when the device is connected to any network type, including cellular/mobile network, WiFi, Ethernet or Bluetooth.
- [C-1-3] MUST support logging in to captive portals using cleartext DNS when the device is configured to use private DNS strict mode.
- [C-1-4] MUST use encrypted DNS as per the SDK documentation for
android.net.LinkProperties.getPrivateDnsServerName
andandroid.net.LinkProperties.isPrivateDnsActive
for all network traffic that is not explicitly communicating with the captive portal. - [C-1-5] MUST ensure that, while the user is logging in to a captive portal, the default network used by applications (as returned by
ConnectivityManager.getActiveNetwork
,ConnectivityManager.registerDefaultNetworkCallback
, and used by default by Java networking APIs such as java.net.Socket, and native APIs such as connect()) is any other available network that provides internet access, if available.
7.4.6. تنظیمات همگام سازی
Device implementations:
- [C-0-1] MUST have the master auto-sync setting on by default so that the method
getMasterSyncAutomatically()
returns “true”.
7.4.7. ذخیره داده
If device implementations include a metered connection, they are:
- [C-SR-1] STRONGLY RECOMMENDED to provide the data saver mode.
If device implementations provide the data saver mode, they:
- [C-1-1] MUST support all the APIs in the
ConnectivityManager
class as described in the SDK documentation
If device implementations do not provide the data saver mode, they:
- [C-2-1] MUST return the value
RESTRICT_BACKGROUND_STATUS_DISABLED
forConnectivityManager.getRestrictBackgroundStatus()
- [C-2-2] MUST NOT broadcast
ConnectivityManager.ACTION_RESTRICT_BACKGROUND_CHANGED
.
7.4.8. Secure Elements
If device implementations support Open Mobile API -capable secure elements and make them available to third-party apps, they:
[C-1-1] MUST enumerate the available secure elements readers via
android.se.omapi.SEService.getReaders()
API.[C-1-2] MUST declare the correct feature flags via
android.hardware.se.omapi.uicc
for the device with UICC-based secure elements,android.hardware.se.omapi.ese
for the device with eSE-based secure elements andandroid.hardware.se.omapi.sd
for the device with SD-based secure elements.
7.5. دوربین ها
If device implementations include at least one camera, they:
- [C-1-1] MUST declare the
android.hardware.camera.any
feature flag. - [C-1-2] MUST be possible for an application to simultaneously allocate 3 RGBA_8888 bitmaps equal to the size of the images produced by the largest-resolution camera sensor on the device, while camera is open for the purpose of basic preview and still گرفتن
- [C-1-3] MUST ensure that the preinstalled default camera application handling intents
MediaStore.ACTION_IMAGE_CAPTURE
,MediaStore.ACTION_IMAGE_CAPTURE_SECURE
, orMediaStore.ACTION_VIDEO_CAPTURE
, is responsible for removing the user location in the image metadata before sending it to the receiving application when the receiving application does not haveACCESS_FINE_LOCATION
.
7.5.1. Rear-Facing Camera
A rear-facing camera is a camera located on the side of the device opposite the display; that is, it images scenes on the far side of the device, like a traditional camera.
Device implementations:
- SHOULD include a rear-facing camera.
If device implementations include at least one rear-facing camera, they:
- [C-1-1] MUST report the feature flag
android.hardware.camera
andandroid.hardware.camera.any
. - [C-1-2] MUST have a resolution of at least 2 megapixels.
- SHOULD have either hardware auto-focus or software auto-focus implemented in the camera driver (transparent to application software).
- MAY have fixed-focus or EDOF (extended depth of field) hardware.
- MAY include a flash.
If the camera includes a flash:
- [C-2-1] the flash lamp MUST NOT be lit while an
android.hardware.Camera.PreviewCallback
instance has been registered on a Camera preview surface, unless the application has explicitly enabled the flash by enabling theFLASH_MODE_AUTO
orFLASH_MODE_ON
attributes of aCamera.Parameters
object. Note that this constraint does not apply to the device's built-in system camera application, but only to third-party applications usingCamera.PreviewCallback
.
7.5.2. Front-Facing Camera
A front-facing camera is a camera located on the same side of the device as the display; that is, a camera typically used to image the user, such as for video conferencing and similar applications.
Device implementations:
- MAY include a front-facing camera.
If device implementations include at least one front-facing camera, they:
- [C-1-1] MUST report the feature flag
android.hardware.camera.any
andandroid.hardware.camera.front
. - [C-1-2] MUST have a resolution of at least VGA (640x480 pixels).
- [C-1-3] MUST NOT use a front-facing camera as the default for the Camera API and MUST NOT configure the API to treat a front-facing camera as the default rear-facing camera, even if it is the only camera روی دستگاه
- [C-1-4] The camera preview MUST be mirrored horizontally relative to the orientation specified by the application when the current application has explicitly requested that the Camera display be rotated via a call to the
android.hardware.Camera.setDisplayOrientation()
method . Conversely, the preview MUST be mirrored along the device's default horizontal axis when the current application does not explicitly request that the Camera display be rotated via a call to theandroid.hardware.Camera.setDisplayOrientation()
method. - [C-1-5] MUST NOT mirror the final captured still image or video streams returned to application callbacks or committed to media storage.
- [C-1-6] MUST mirror the image displayed by the postview in the same manner as the camera preview image stream.
- MAY include features (such as auto-focus, flash, etc.) available to rear-facing cameras as described in section 7.5.1 .
If device implementations are capable of being rotated by user (such as automatically via an accelerometer or manually via user input):
- [C-2-1] The camera preview MUST be mirrored horizontally relative to the device's current orientation.
7.5.3. External Camera
Device implementations:
- MAY include support for an external camera that is not necessarily always connected.
If device implementations include support for an external camera, they:
- [C-1-1] MUST declare the platform feature flag
android.hardware.camera.external
andandroid.hardware camera.any
. - [C-1-2] MUST support USB Video Class (UVC 1.0 or higher) if the external camera connects through the USB host port.
- [C-1-3] MUST pass camera CTS tests with a physical external camera device connected. Details of camera CTS testing are available at source.android.com .
- SHOULD support video compressions such as MJPEG to enable transfer of high-quality unencoded streams (ie raw or independently compressed picture streams).
- MAY support multiple cameras.
- MAY support camera-based video encoding.
If camera-based video encoding is supported:
- [C-2-1] A simultaneous unencoded / MJPEG stream (QVGA or greater resolution) MUST be accessible to the device implementation.
7.5.4. Camera API Behavior
Android includes two API packages to access the camera, the newer android.hardware.camera2 API expose lower-level camera control to the app, including efficient zero-copy burst/streaming flows and per-frame controls of exposure, gain, white balance gains, color conversion, denoising, sharpening, and more.
The older API package, android.hardware.Camera
, is marked as deprecated in Android 5.0 but as it should still be available for apps to use. Android device implementations MUST ensure the continued support of the API as described in this section and in the Android SDK.
All features that are common between the deprecated android.hardware.Camera class and the newer android.hardware.camera2 package MUST have equivalent performance and quality in both APIs. For example, with equivalent settings, autofocus speed and accuracy must be identical, and the quality of captured images must be the same. Features that depend on the different semantics of the two APIs are not required to have matching speed or quality, but SHOULD match as closely as possible.
Device implementations MUST implement the following behaviors for the camera-related APIs, for all available cameras. Device implementations:
- [C-0-1] MUST use
android.hardware.PixelFormat.YCbCr_420_SP
for preview data provided to application callbacks when an application has never calledandroid.hardware.Camera.Parameters.setPreviewFormat(int)
. - [C-0-2] MUST further be in the NV21 encoding format when an application registers an
android.hardware.Camera.PreviewCallback
instance and the system calls theonPreviewFrame()
method and the preview format is YCbCr_420_SP, the data in the byte[] passed intoonPreviewFrame()
. That is, NV21 MUST be the default. - [C-0-3] MUST support the YV12 format (as denoted by the
android.graphics.ImageFormat.YV12
constant) for camera previews for both front- and rear-facing cameras forandroid.hardware.Camera
. (The hardware video encoder and camera may use any native pixel format, but the device implementation MUST support conversion to YV12.) - [C-0-4] MUST support the
android.hardware.ImageFormat.YUV_420_888
andandroid.hardware.ImageFormat.JPEG
formats as outputs through theandroid.media.ImageReader
API forandroid.hardware.camera2
devices that advertiseREQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE
capability inandroid.request.availableCapabilities
. - [C-0-5] MUST still implement the full Camera API included in the Android SDK documentation, regardless of whether the device includes hardware autofocus or other capabilities. For instance, cameras that lack autofocus MUST still call any registered
android.hardware.Camera.AutoFocusCallback
instances (even though this has no relevance to a non-autofocus camera.) Note that this does apply to front-facing cameras; for instance, even though most front-facing cameras do not support autofocus, the API callbacks must still be “faked” as described. - [C-0-6] MUST recognize and honor each parameter name defined as a constant in the
android.hardware.Camera.Parameters
class and theandroid.hardware.camera2.CaptureRequest
class. Conversely, device implementations MUST NOT honor or recognize string constants passed to theandroid.hardware.Camera.setParameters()
method other than those documented as constants on theandroid.hardware.Camera.Parameters
. That is, device implementations MUST support all standard Camera parameters if the hardware allows, and MUST NOT support custom Camera parameter types. For instance, device implementations that support image capture using high dynamic range (HDR) imaging techniques MUST support camera parameterCamera.SCENE_MODE_HDR
. - [C-0-7] MUST report the proper level of support with the
android.info.supportedHardwareLevel
property as described in the Android SDK and report the appropriate framework feature flags . - [C-0-8] MUST also declare its individual camera capabilities of
android.hardware.camera2
via theandroid.request.availableCapabilities
property and declare the appropriate feature flags ; MUST define the feature flag if any of its attached camera devices supports the feature. - [C-0-9] MUST broadcast the
Camera.ACTION_NEW_PICTURE
intent whenever a new picture is taken by the camera and the entry of the picture has been added to the media store. - [C-0-10] MUST broadcast the
Camera.ACTION_NEW_VIDEO
intent whenever a new video is recorded by the camera and the entry of the picture has been added to the media store. - [C-0-11] MUST have all cameras accessible via the deprecated
android.hardware.Camera
API also accessible via theandroid.hardware.camera2
API. - [C-0-12] MUST ensure that the facial appearance is NOT altered, including but not limited to altering facial geometry, facial skin tone, or facial skin smoothening for any
android.hardware.camera2
orandroid.hardware.Camera
API. - [C-SR-1] For devices with multiple RGB cameras facing in the same direction, are STRONGLY RECOMMENDED to support a logical camera device that lists capability
CameraMetadata.REQUEST_AVAILABLE_CAPABILITIES_LOGICAL_MULTI_CAMERA
, consisting of all of the RGB cameras facing that direction as physical sub-devices .
If device implementations provide a proprietary camera API to 3rd-party apps, they:
- [C-1-1] MUST implement such a camera API using
android.hardware.camera2
API. - MAY provide vendor tags and/or extensions to
android.hardware.camera2
API.
7.5.5. Camera Orientation
If device implementations have a front- or a rear-facing camera, such camera(s):
- [C-1-1] MUST be oriented so that the long dimension of the camera aligns with the screen's long dimension. That is, when the device is held in the landscape orientation, cameras MUST capture images in the landscape orientation. This applies regardless of the device's natural orientation; that is, it applies to landscape-primary devices as well as portrait-primary devices.
Devices that fulfill all of the following criteria are exempt from the requirement above:
- The device implements variable-geometry screens, such as foldable or hinged displays.
- When the device's fold or hinge state changes, the device switches between portrait-primary to landscape-primary (or vice-versa) orientations.
7.6. حافظه و ذخیره سازی
7.6.1. Minimum Memory and Storage
Device implementations:
- [C-0-1] MUST include a Download Manager that applications MAY use to download data files and they MUST be capable of downloading individual files of at least 100MB in size to the default "cache" location.
7.6.2. Application Shared Storage
Device implementations:
- [C-0-1] MUST offer storage to be shared by applications, also often referred as "shared external storage", "application shared storage" or by the Linux path "/sdcard" it is mounted on.
- [C-0-2] MUST be configured with shared storage mounted by default, in other words "out of the box", regardless of whether the storage is implemented on an internal storage component or a removable storage medium (eg Secure Digital card slot ).
- [C-0-3] MUST mount the application shared storage directly on the Linux path
sdcard
or include a Linux symbolic link fromsdcard
to the actual mount point. - [C-0-4] MUST enable scoped storage by default for all apps targeting API level 29 or above, except in the following situation:
- When the app has requested
android:requestLegacyExternalStorage="true"
in their manifest.
- When the app has requested
- [C-0-5] MUST redact location metadata, such as GPS Exif tags, stored in media files when those files are accessed through
MediaStore
, except when the calling app holds theACCESS_MEDIA_LOCATION
permission.
Device implementations MAY meet the above requirements using either of the following:
- User-accessible removable storage, such as a Secure Digital (SD) card slot.
- A portion of the internal (non-removable) storage as implemented in the Android Open Source Project (AOSP).
If device implementations use removable storage to satisfy the above requirements, they:
- [C-1-1] MUST implement a toast or pop-up user interface warning the user when there is no storage medium inserted in the slot.
- [C-1-2] MUST include a FAT-formatted storage medium (eg SD card) or show on the box and other material available at time of purchase that the storage medium has to be purchased separately.
If device implementations use a portion of the non-removable storage to satisfy the above requirements, they:
- SHOULD use the AOSP implementation of the internal application shared storage.
- MAY share the storage space with the application private data.
If device implementations have a USB port with USB peripheral mode support, they:
- [C-3-1] MUST provide a mechanism to access the data on the application shared storage from a host computer.
- SHOULD expose content from both storage paths transparently through Android's media scanner service and
android.provider.MediaStore
. - MAY use USB mass storage, but SHOULD use Media Transfer Protocol to satisfy this requirement.
If device implementations have a USB port with USB peripheral mode and support Media Transfer Protocol, they:
- SHOULD be compatible with the reference Android MTP host, Android File Transfer .
- SHOULD report a USB device class of 0x00.
- SHOULD report a USB interface name of 'MTP'.
7.6.3. Adoptable Storage
If the device is expected to be mobile in nature unlike Television, device implementations are:
- [C-SR-1] STRONGLY RECOMMENDED to implement the adoptable storage in a long-term stable location, since accidentally disconnecting them can cause data loss/corruption.
If the removable storage device port is in a long-term stable location, such as within the battery compartment or other protective cover, device implementations are:
- [C-SR-2] STRONGLY RECOMMENDED to implement adoptable storage .
7.7. USB
If device implementations have a USB port, they:
- SHOULD support USB peripheral mode and SHOULD support USB host mode.
- SHOULD support disabling data signaling over USB.
7.7.1. USB peripheral mode
If device implementations include a USB port supporting peripheral mode:
- [C-1-1] The port MUST be connectable to a USB host that has a standard type-A or type-C USB port.
- [C-1-2] MUST report the correct value of
iSerialNumber
in USB standard device descriptor throughandroid.os.Build.SERIAL
. - [C-1-3] MUST detect 1.5A and 3.0A chargers per the Type-C resistor standard and MUST detect changes in the advertisement if they support Type-C USB.
- [C-SR-1] The port SHOULD use micro-B, micro-AB or Type-C USB form factor. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases.
- [C-SR-2] The port SHOULD be located on the bottom of the device (according to natural orientation) or enable software screen rotation for all apps (including home screen), so that the display draws correctly when the device is oriented with the port at bottom. Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to future platform releases.
- [C-SR-3] SHOULD implement support to draw 1.5 A current during HS chirp and traffic as specified in the USB Battery Charging specification, revision 1.2 . Existing and new Android devices are STRONGLY RECOMMENDED to meet these requirements so they will be able to upgrade to the future platform releases.
- [C-SR-4] STRONGLY RECOMMENDED to not support proprietary charging methods that modify Vbus voltage beyond default levels, or alter sink/source roles as such may result in interoperability issues with the chargers or devices that support the standard USB Power Delivery methods. While this is called out as "STRONGLY RECOMMENDED", in future Android versions we might REQUIRE all type-C devices to support full interoperability with standard type-C chargers.
- [C-SR-5] STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping when they support Type-C USB and USB host mode.
- SHOULD support Power Delivery for high-voltage charging and support for Alternate Modes such as display out.
- SHOULD implement the Android Open Accessory (AOA) API and specification as documented in the Android SDK documentation.
If device implementations include a USB port and implement the AOA specification, they:
- [C-2-1] MUST declare support for the hardware feature
android.hardware.usb.accessory
. - [C-2-2] The USB mass storage class MUST include the string "android" at the end of the interface description
iInterface
string of the USB mass storage
7.7.2. USB host mode
If device implementations include a USB port supporting host mode, they:
- [C-1-1] MUST implement the Android USB host API as documented in the Android SDK and MUST declare support for the hardware feature
android.hardware.usb.host
. - [C-1-2] MUST implement support to connect standard USB peripherals, in other words, they MUST either:
- Have an on-device type C port or ship with cable(s) adapting an on-device proprietary port to a standard USB type-C port (USB Type-C device).
- Have an on-device type A or ship with cable(s) adapting an on-device proprietary port to a standard USB type-A port.
- Have an on-device micro-AB port, which SHOULD ship with a cable adapting to a standard type-A port.
- [C-1-3] MUST NOT ship with an adapter converting from USB type A or micro-AB ports to a type-C port (receptacle).
- [C-SR-1] Are STRONGLY RECOMMENDED to implement the USB audio class as documented in the Android SDK documentation.
- SHOULD support charging the connected USB peripheral device while in host mode; advertising a source current of at least 1.5A as specified in the Termination Parameters section of the USB Type-C Cable and Connector Specification Revision 1.2 for USB Type-C connectors or using Charging Downstream Port(CDP) output current range as specified in the USB Battery Charging specifications, revision 1.2 for Micro-AB connectors.
- SHOULD implement and support USB Type-C standards.
If device implementations include a USB port supporting host mode and the USB audio class, they:
- [C-2-1] MUST support the USB HID class .
- [C-2-2] MUST support the detection and mapping of the following HID data fields specified in the USB HID Usage Tables and the Voice Command Usage Request to the
KeyEvent
constants as below:- Usage Page (0xC) Usage ID (0x0CD):
KEYCODE_MEDIA_PLAY_PAUSE
- Usage Page (0xC) Usage ID (0x0E9):
KEYCODE_VOLUME_UP
- Usage Page (0xC) Usage ID (0x0EA):
KEYCODE_VOLUME_DOWN
- Usage Page (0xC) Usage ID (0x0CF):
KEYCODE_VOICE_ASSIST
- Usage Page (0xC) Usage ID (0x0CD):
If device implementations include a USB port supporting host mode and the Storage Access Framework (SAF), they:
- [C-3-1] MUST recognize any remotely connected MTP (Media Transfer Protocol) devices and make their contents accessible through the
ACTION_GET_CONTENT
,ACTION_OPEN_DOCUMENT
, andACTION_CREATE_DOCUMENT
intents. .
If device implementations include a USB port supporting host mode and USB Type-C, they:
- [C-4-1] MUST implement Dual Role Port functionality as defined by the USB Type-C specification (section 4.5.1.3.3).
- [C-SR-2] STRONGLY RECOMMENDED to support DisplayPort, SHOULD support USB SuperSpeed Data Rates, and are STRONGLY RECOMMENDED to support Power Delivery for data and power role swapping.
- [C-SR-3] STRONGLY RECOMMENDED to NOT support Audio Adapter Accessory Mode as described in the Appendix A of the USB Type-C Cable and Connector Specification Revision 1.2 .
- SHOULD implement the Try.* model that is most appropriate for the device form factor. For example a handheld device SHOULD implement the Try.SNK model.
7.8. صوتی
7.8.1. میکروفون
If device implementations include a microphone, they:
- [C-1-1] MUST report the
android.hardware.microphone
feature constant. - [C-1-2] MUST meet the audio recording requirements in section 5.4 .
- [C-1-3] MUST meet the audio latency requirements in section 5.6 .
- [C-SR-1] Are STRONGLY RECOMMENDED to support near-ultrasound recording as described in section 7.8.3 .
If device implementations omit a microphone, they:
- [C-2-1] MUST NOT report the
android.hardware.microphone
feature constant. - [C-2-2] MUST implement the audio recording API at least as no-ops, per section 7 .
7.8.2. خروجی صدا
If device implementations include a speaker or an audio/multimedia output port for an audio output peripheral such as a 4 conductor 3.5mm audio jack or USB host mode port using USB audio class , they:
- [C-1-1] MUST report the
android.hardware.audio.output
feature constant. - [C-1-2] MUST meet the audio playback requirements in section 5.5 .
- [C-1-3] MUST meet the audio latency requirements in section 5.6 .
- [C-SR-1] STRONGLY RECOMMENDED to support near-ultrasound playback as described in section 7.8.3 .
If device implementations do not include a speaker or audio output port, they:
- [C-2-1] MUST NOT report the
android.hardware.audio.output
feature. - [C-2-2] MUST implement the Audio Output related APIs as no-ops at least.
For the purposes of this section, an "output port" is a physical interface such as a 3.5mm audio jack, HDMI, or USB host mode port with USB audio class. Support for audio output over radio-based protocols such as Bluetooth, WiFi, or cellular network does not qualify as including an "output port".
7.8.2.1. Analog Audio Ports
In order to be compatible with the headsets and other audio accessories using the 3.5mm audio plug across the Android ecosystem, if device implementations include one or more analog audio ports, they:
- [C-SR-1] Are STRONGLY RECOMMENDED to include at least one of the audio port(s) to be a 4 conductor 3.5mm audio jack.
If device implementations have a 4 conductor 3.5mm audio jack, they:
- [C-1-1] MUST support audio playback to stereo headphones and stereo headsets with a microphone.
- [C-1-2] MUST support TRRS audio plugs with the CTIA pin-out order.
- [C-1-3] MUST support the detection and mapping to the keycodes for the following 3 ranges of equivalent impedance between the microphone and ground conductors on the audio plug:
- 70 ohm or less :
KEYCODE_HEADSETHOOK
- 210-290 ohm :
KEYCODE_VOLUME_UP
- 360-680 ohm :
KEYCODE_VOLUME_DOWN
- 70 ohm or less :
- [C-1-4] MUST trigger
ACTION_HEADSET_PLUG
upon a plug insert, but only after all contacts on plug are touching their relevant segments on the jack. - [C-1-5] MUST be capable of driving at least 150mV ± 10% of output voltage on a 32 ohm speaker impedance.
- [C-1-6] MUST have a microphone bias voltage between 1.8V ~ 2.9V.
- [C-1-7] MUST detect and map to the keycode for the following range of equivalent impedance between the microphone and ground conductors on the audio plug:
- 110-180 ohm:
KEYCODE_VOICE_ASSIST
- 110-180 ohm:
- [C-SR-2] Are STRONGLY RECOMMENDED to support audio plugs with the OMTP pin-out order.
- [C-SR-3] Are STRONGLY RECOMMENDED to support audio recording from stereo headsets with a microphone.
If device implementations have a 4 conductor 3.5mm audio jack and support a microphone, and broadcast the android.intent.action.HEADSET_PLUG
with the extra value microphone set as 1, they:
- [C-2-1] MUST support the detection of microphone on the plugged in audio accessory.
7.8.2.2. Digital Audio Ports
In order to be compatible with the headsets and other audio accessories using USB-C connectors and implementing (USB audio class) across the Android ecosystem as defined in Android USB headset specification .
See Section 2.2.1 for device-specific requirements.
7.8.3. Near-Ultrasound
Near-Ultrasound audio is the 18.5 kHz to 20 kHz band.
Device implementations:
- MUST correctly report the support of near-ultrasound audio capability via the AudioManager.getProperty API as follows:
If PROPERTY_SUPPORT_MIC_NEAR_ULTRASOUND
is "true", the following requirements MUST be met by the VOICE_RECOGNITION
and UNPROCESSED
audio sources:
- [C-1-1] The microphone's mean power response in the 18.5 kHz to 20 kHz band MUST be no more than 15 dB below the response at 2 kHz.
- [C-1-2] The microphone's unweighted signal to noise ratio over 18.5 kHz to 20 kHz for a 19 kHz tone at -26 dBFS MUST be no lower than 50 dB.
If PROPERTY_SUPPORT_SPEAKER_NEAR_ULTRASOUND
is "true":
- [C-2-1] The speaker's mean response in 18.5 kHz - 20 kHz MUST be no lower than 40 dB below the response at 2 kHz.
7.8.4. Signal Integrity
Device implementations:
- SHOULD provide a glitch-free audio signal path for both input and output streams on handheld devices, as defined by zero glitches measured during a test of one minute per path. Test using OboeTester “Automated Glitch Test”.
The test requires an audio loopback dongle , used directly in a 3.5mm jack, and/or in combination with a USB-C to 3.5mm adapter. All audio output ports SHOULD be tested.
OboeTester currently supports AAudio paths, so the following combinations SHOULD be tested for glitches using AAudio:
Perf Mode | اشتراک گذاری | Out Sample Rate | In Chans | Out Chans |
---|---|---|---|---|
LOW_LATENCY | انحصاری | UNSPECIFIED | 1 | 2 |
LOW_LATENCY | انحصاری | UNSPECIFIED | 2 | 1 |
LOW_LATENCY | به اشتراک گذاشته شده | UNSPECIFIED | 1 | 2 |
LOW_LATENCY | به اشتراک گذاشته شده | UNSPECIFIED | 2 | 1 |
هیچ کدام | به اشتراک گذاشته شده | 48000 | 1 | 2 |
هیچ کدام | به اشتراک گذاشته شده | 48000 | 2 | 1 |
هیچ کدام | به اشتراک گذاشته شده | 44100 | 1 | 2 |
هیچ کدام | به اشتراک گذاشته شده | 44100 | 2 | 1 |
هیچ کدام | به اشتراک گذاشته شده | 16000 | 1 | 2 |
هیچ کدام | به اشتراک گذاشته شده | 16000 | 2 | 1 |
A reliable stream SHOULD meet the following criteria for Signal to Noise Ratio (SNR) and Total Harmonic Distortion (THD) for 2000 Hz sine.
مبدل | THD | SNR |
---|---|---|
primary built-in speaker, measured using an external reference microphone | < 3.0% | >= 50 dB |
primary built-in microphone, measured using an external reference speaker | < 3.0% | >= 50 dB |
built-in analog 3.5 mm jacks, tested using loopback adapter | < 1% | >= 60 dB |
USB adapters supplied with the phone, tested using loopback adapter | < 1.0٪ | >= 60 dB |
7.9. واقعیت مجازی
Android includes APIs and facilities to build "Virtual Reality" (VR) applications including high quality mobile VR experiences. Device implementations MUST properly implement these APIs and behaviors, as detailed in this section.
7.9.1. Virtual Reality Mode
Android includes support for VR Mode , a feature which handles stereoscopic rendering of notifications and disables monocular system UI components while a VR application has user focus.
7.9.2. Virtual Reality Mode - High Performance
If device implementations support VR mode, they:
- [C-1-1] MUST have at least 2 physical cores.
- [C-1-2] MUST declare the
android.hardware.vr.high_performance
feature. - [C-1-3] MUST support sustained performance mode.
- [C-1-4] MUST support OpenGL ES 3.2.
- [C-1-5] MUST support
android.hardware.vulkan.level
0. - SHOULD support
android.hardware.vulkan.level
1 or higher. - [C-1-6] MUST implement
EGL_KHR_mutable_render_buffer
,EGL_ANDROID_front_buffer_auto_refresh
,EGL_ANDROID_get_native_client_buffer
,EGL_KHR_fence_sync
,EGL_KHR_wait_sync
,EGL_IMG_context_priority
,EGL_EXT_protected_content
,EGL_EXT_image_gl_colorspace
, and expose the extensions in the list of available EGL extensions. - [C-1-8] MUST implement
GL_EXT_multisampled_render_to_texture2
,GL_OVR_multiview
,GL_OVR_multiview2
,GL_EXT_protected_textures
, and expose the extensions in the list of available GL extensions. - [C-SR-1] Are STRONGLY RECOMMENDED to implement
GL_EXT_external_buffer
,GL_EXT_EGL_image_array
,GL_OVR_multiview_multisampled_render_to_texture
, and expose the extensions in the list of available GL extensions. - [C-SR-2] Are STRONGLY RECOMMENDED to support Vulkan 1.1.
- [C-SR-3] Are STRONGLY RECOMMENDED to implement
VK_ANDROID_external_memory_android_hardware_buffer
,VK_GOOGLE_display_timing
,VK_KHR_shared_presentable_image
, and expose it in the list of available Vulkan extensions. - [C-SR-4] Are STRONGLY RECOMMENDED to expose at least one Vulkan queue family where
flags
contain bothVK_QUEUE_GRAPHICS_BIT
andVK_QUEUE_COMPUTE_BIT
, andqueueCount
is at least 2. - [C-1-7] The GPU and display MUST be able to synchronize access to the shared front buffer such that alternating-eye rendering of VR content at 60fps with two render contexts will be displayed with no visible tearing artifacts.
- [C-1-9] MUST implement support for
AHardwareBuffer
flagsAHARDWAREBUFFER_USAGE_GPU_DATA_BUFFER
,AHARDWAREBUFFER_USAGE_SENSOR_DIRECT_DATA
andAHARDWAREBUFFER_USAGE_PROTECTED_CONTENT
as described in the NDK. - [C-1-10] MUST implement support for
AHardwareBuffer
s with any combination of the usage flagsAHARDWAREBUFFER_USAGE_GPU_COLOR_OUTPUT
,AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE
,AHARDWAREBUFFER_USAGE_PROTECTED_CONTENT
for at least the following formats:AHARDWAREBUFFER_FORMAT_R5G6B5_UNORM
,AHARDWAREBUFFER_FORMAT_R8G8B8A8_UNORM
,AHARDWAREBUFFER_FORMAT_R10G10B10A2_UNORM
,AHARDWAREBUFFER_FORMAT_R16G16B16A16_FLOAT
. - [C-SR-5] Are STRONGLY RECOMMENDED to support the allocation of
AHardwareBuffer
s with more than one layer and flags and formats specified in C-1-10. - [C-1-11] MUST support H.264 decoding at least 3840 x 2160 at 30fps, compressed to an average of 40Mbps (equivalent to 4 instances of 1920 x1080 at 30 fps-10 Mbps or 2 instances of 1920 x 1080 at 60 fps-20 Mbps).
- [C-1-12] MUST support HEVC and VP9, MUST be capable of decoding at least 1920 x 1080 at 30 fps compressed to an average of 10 Mbps and SHOULD be capable of decoding 3840 x 2160 at 30 fps-20 Mbps (equivalent to 4 instances of 1920 x 1080 at 30 fps-5 Mbps).
- [C-1-13] MUST support
HardwarePropertiesManager.getDeviceTemperatures
API and return accurate values for skin temperature. - [C-1-14] MUST have an embedded screen, and its resolution MUST be at least 1920 x 1080.
- [C-SR-6] Are STRONGLY RECOMMENDED to have a display resolution of at least 2560 x 1440.
- [C-1-15] The display MUST update at least 60 Hz while in VR Mode.
- [C-1-17] The display MUST support a low-persistence mode with ≤ 5 milliseconds persistence, persistence being defined as the amount of time for which a pixel is emitting light.
- [C-1-18] MUST support Bluetooth 4.2 and Bluetooth LE Data Length Extension section 7.4.3 .
- [C-1-19] MUST support and properly report Direct Channel Type for all of the following default sensor types:
-
TYPE_ACCELEROMETER
-
TYPE_ACCELEROMETER_UNCALIBRATED
-
TYPE_GYROSCOPE
-
TYPE_GYROSCOPE_UNCALIBRATED
-
TYPE_MAGNETIC_FIELD
-
TYPE_MAGNETIC_FIELD_UNCALIBRATED
-
- [C-SR-7] Are STRONGLY RECOMMENDED to support the
TYPE_HARDWARE_BUFFER
direct channel type for all Direct Channel Types listed above. - [C-1-21] MUST meet the gyroscope, accelerometer, and magnetometer related requirements for
android.hardware.hifi_sensors
, as specified in section 7.3.9 . - [C-SR-8] Are STRONGLY RECOMMENDED to support the
android.hardware.sensor.hifi_sensors
feature. - [C-1-22] MUST have end-to-end motion to photon latency not higher than 28 milliseconds.
- [C-SR-9] Are STRONGLY RECOMMENDED to have end-to-end motion to photon latency not higher than 20 milliseconds.
- [C-1-23] MUST have first-frame ratio, which is the ratio between the brightness of pixels on the first frame after a transition from black to white and the brightness of white pixels in steady state, of at least 85%.
- [C-SR-10] Are STRONGLY RECOMMENDED to have first-frame ratio of at least 90%.
- MAY provide an exclusive core to the foreground application and MAY support the
Process.getExclusiveCores
API to return the numbers of the cpu cores that are exclusive to the top foreground application.
If exclusive core is supported, then the core:
- [C-2-1] MUST not allow any other userspace processes to run on it (except device drivers used by the application), but MAY allow some kernel processes to run as necessary.
7.10. هپتیک
See Section 2.2.1 for device-specific requirements.
7.11. Media Performance Class
The media performance class of the device implementation can be obtained from the android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
. Requirements for media performance class are defined for each Android version starting with R (version 30). The special value of 0 designates that the device is not of a media performance class.
If device implementations return non-zero value for android.os.Build.VERSION.MEDIA_PERFORMANCE_CLASS
, they:
[C-1-1] MUST return at least a value of
android.os.Build.VERSION_CODES.R
.[C-1-2] MUST be a handheld device implementation.
[C-1-3] MUST meet all requirements for "Media Performance Class" described in section 2.2.7 .
See section 2.2.7 for device-specific requirements.
8. Performance and Power
Some minimum performance and power criteria are critical to the user experience and impact the baseline assumptions developers would have when developing an app.
8.1. User Experience Consistency
A smooth user interface can be provided to the end user if there are certain minimum requirements to ensure a consistent frame rate and response times for applications and games. Device implementations, depending on the device type, MAY have measurable requirements for the user interface latency and task switching as described in section 2 .
8.2. File I/O Access Performance
Providing a common baseline for a consistent file access performance on the application private data storage ( /data
partition) allows app developers to set a proper expectation that would help their software design. Device implementations, depending on the device type, MAY have certain requirements described in section 2 for the following read and write operations:
- Sequential write performance . Measured by writing a 256MB file using 10MB write buffer.
- Random write performance . Measured by writing a 256MB file using 4KB write buffer.
- Sequential read performance . Measured by reading a 256MB file using 10MB write buffer.
- Random read performance . Measured by reading a 256MB file using 4KB write buffer.
8.3. Power-Saving Modes
If device implementations include features to improve device power management that are included in AOSP (eg App Standby Bucket, Doze) or extend the features to apply stronger restrictions than the RESTRICTED App Standby Bucket , they:
- [C-1-1] MUST NOT deviate from the AOSP implementation for the triggering, maintenance, wakeup algorithms and the use of global system settings or DeviceConfig of App Standby and Doze power-saving modes.
- [C-1-2] MUST NOT deviate from the AOSP implementation for the use of global settings or DeviceConfig to manage the throttling of jobs, alarm and network for apps in each bucket for App standby.
- [C-1-3] MUST NOT deviate from the AOSP implementation for the number of the App Standby Buckets used for App Standby.
- [C-1-4] MUST implement App Standby Buckets and Doze as described in Power Management .
- [C-1-5] MUST return
true
forPowerManager.isPowerSaveMode()
when the device is on power save mode. - [C-1-6] MUST provide user affordance to display all apps that are exempted from App Standby and Doze power-saving modes or any battery optimizations and MUST implement the ACTION_REQUEST_IGNORE_BATTERY_OPTIMIZATIONS intent to ask the user to allow an app to ignore battery optimizations.
- [C-SR-1] Are STRONGLY RECOMMENDED to provide user affordance to enable and disable the battery saver feature.
- [C-SR-2] Are STRONGLY RECOMMENDED to provide user affordance to display all apps that are exempted from App Standby and Doze power-saving modes.
If device implementations extend power management features that are included in AOSP and that extension applies more stringent restrictions than the Rare App Standby Bucket , refer to section 3.5.1 .
In addition to the power-saving modes, Android device implementations MAY implement any or all of the 4 sleeping power states as defined by the Advanced Configuration and Power Interface (ACPI).
If device implementations implement S4 power states as defined by the ACPI, they:
- [C-1-1] MUST enter this state only after the user has taken an explicit action to put the device in an inactive state (eg by closing a lid that is physically part of the device or turning off a vehicle or television) and before the user re-activates the device (eg by opening the lid or turning the vehicle or television back on).
If device implementations implement S3 power states as defined by the ACPI, they:
[C-2-1] MUST meet C-1-1 above, or, MUST enter S3 state only when third-party applications do not need the system resources (eg the screen, CPU).
Conversely, MUST exit from S3 state when third-party applications need the system resources, as described on this SDK.
For example, while the third-party applications request to keep the screen on through
FLAG_KEEP_SCREEN_ON
or keep CPU running throughPARTIAL_WAKE_LOCK
, the device MUST NOT enter S3 state unless, as described in C-1-1, the user has taken explicit action to put the device in an inactive state. Conversely, at a time when a task that third-party apps implement through JobScheduler is triggered or Firebase Cloud Messaging is delivered to third-party apps, the device MUST exit the S3 state unless the user has put the device in an inactive state. These are not comprehensive examples and AOSP implements extensive wake-up signals that trigger a wakeup from this state.
8.4. Power Consumption Accounting
A more accurate accounting and reporting of the power consumption provides the app developer both the incentives and the tools to optimize the power usage pattern of the application.
Device implementations:
- [C-SR-1] STRONGLY RECOMMENDED to provide a per-component power profile that defines the current consumption value for each hardware component and the approximate battery drain caused by the components over time as documented in the Android Open Source Project site.
- [C-SR-2] STRONGLY RECOMMENDED to report all power consumption values in milliampere hours (mAh).
- [C-SR-3] STRONGLY RECOMMENDED to report CPU power consumption per each process's UID. The Android Open Source Project meets the requirement through the
uid_cputime
kernel module implementation. - [C-SR-4] STRONGLY RECOMMENDED to make this power usage available via the
adb shell dumpsys batterystats
shell command to the app developer. - SHOULD be attributed to the hardware component itself if unable to attribute hardware component power usage to an application.
8.5. Consistent Performance
Performance can fluctuate dramatically for high-performance long-running apps, either because of the other apps running in the background or the CPU throttling due to temperature limits. Android includes programmatic interfaces so that when the device is capable, the top foreground application can request that the system optimize the allocation of the resources to address such fluctuations.
Device implementations:
[C-0-1] MUST report the support of Sustained Performance Mode accurately through the
PowerManager.isSustainedPerformanceModeSupported()
API method.SHOULD support Sustained Performance Mode.
If device implementations report support of Sustained Performance Mode, they:
- [C-1-1] MUST provide the top foreground application a consistent level of performance for at least 30 minutes, when the app requests it.
- [C-1-2] MUST honor the
Window.setSustainedPerformanceMode()
API and other related APIs.
If device implementations include two or more CPU cores, they:
- SHOULD provide at least one exclusive core that can be reserved by the top foreground application.
If device implementations support reserving one exclusive core for the top foreground application, they:
- [C-2-1] MUST report through the
Process.getExclusiveCores()
API method the ID numbers of the exclusive cores that can be reserved by the top foreground application. - [C-2-2] MUST not allow any user space processes except the device drivers used by the application to run on the exclusive cores, but MAY allow some kernel processes to run as necessary.
If device implementations do not support an exclusive core, they:
- [C-3-1] MUST return an empty list through the
Process.getExclusiveCores()
API method.
9. Security Model Compatibility
Device implementations:
[C-0-1] MUST implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs in the Android developer documentation.
[C-0-2] MUST support installation of self-signed applications without requiring any additional permissions/certificates from any third parties/authorities.
If device implementations declare the android.hardware.security.model.compatible
feature, they:
- [C-1-1] MUST support the requirements listed in the following subsections.
9.1. مجوزها
Device implementations:
[C-0-1] MUST support the Android permissions model and the Android Roles Model as defined in the Android developer documentation. Specifically, they MUST enforce each permission and role defined as described in the SDK documentation; no permissions and no roles may be omitted, altered, or ignored.
MAY add additional permissions, provided the new permission ID strings are not in the
android.\*
namespace.[C-0-2] Permissions with a
protectionLevel
ofPROTECTION_FLAG_PRIVILEGED
MUST only be granted to apps preinstalled in the privileged path(s) of the system image and within the subset of the explicitly allowlisted permissions for each app. The AOSP implementation meets this requirement by reading and honoring the allowlisted permissions for each app from the files in theetc/permissions/
path and using thesystem/priv-app
path as the privileged path.
Permissions with a protection level of dangerous are runtime permissions. Applications with targetSdkVersion
> 22 request them at runtime.
Device implementations:
- [C-0-3] MUST show a dedicated interface for the user to decide whether to grant the requested runtime permissions and also provide an interface for the user to manage runtime permissions.
- [C-0-4] MUST have one and only one implementation of both user interfaces.
- [C-0-5] MUST NOT grant any runtime permissions to preinstalled apps unless:
- The user's consent can be obtained before the application uses it.
- The runtime permissions are associated with an intent pattern for which the preinstalled application is set as the default handler.
- [C-0-6] MUST grant the
android.permission.RECOVER_KEYSTORE
permission only to system apps that register a properly secured Recovery Agent. A properly secured Recovery Agent is defined as an on-device software agent that synchronizes with an off-device remote storage, that is equipped with secure hardware with protection equivalent or stronger than what is described in Google Cloud Key Vault Service to prevent brute-force attacks on the lockscreen knowledge factor.
Device implementations:
[C-0-7] MUST adhere to Android location permission properties when an app requests the location or physical activity data through standard Android API or proprietary mechanism. Such data includes but not limited to:
- Device's location (eg latitude and longitude) as described in section 9.8.8 .
- Information that can be used to determine or estimate the device's location (eg SSID, BSSID, Cell ID, or location of the network that the device is connected to).
- User's physical activity or classification of the physical activity.
More specifically, device implementations:
- [C-0-8] MUST obtain user consent to allow an app to access the location or physical activity data.
- [C-0-9] MUST grant a runtime permission ONLY to the app that holds sufficient permission as described on SDK. For example, TelephonyManager#getServiceState requires
android.permission.ACCESS_FINE_LOCATION
.
The only exceptions to the Android location permission properties above are for apps not accessing Location to derive or identify user location; به طور خاص:
- When apps hold the
RADIO_SCAN_WITHOUT_LOCATION
permission. - For device configuration and setup purposes, where system apps hold the
NETWORK_SETTINGS
orNETWORK_SETUP_WIZARD
permission.
Permissions can be marked as restricted altering their behavior.
[C-0-10] Permissions marked with the flag
hardRestricted
MUST NOT be granted to an app unless:- An app APK file is in the system partition.
- The user assigns a role that is associated with the
hardRestricted
permissions to an app. - The installer grants the
hardRestricted
to an app. - An app is granted the
hardRestricted
on an earlier Android version.
[C-0-11] Apps holding a
softRestricted
permission MUST get only limited access and MUST NOT gain full access until allowlisted as described in the SDK, where full and limited access is defined for eachsoftRestricted
permission (for example,READ_EXTERNAL_STORAGE
).[C-0-12] MUST NOT provide any custom functions or APIs to bypass the permission restrictions defined in setPermissionPolicy and setPermissionGrantState APIs.
[C-0-13] MUST use the AppOpsManager APIs to record and track each and every programmatic access of data protected by dangerous permissions from Android activities and services.
[C-0-14] MUST only assign roles to applications with functionalities that meet the role requirements.
[C-0-15] MUST not define roles that are duplicates or superset functionality of roles defined by the platform.
If devices report android.software.managed_users
, they:
- [C-1-1] MUST NOT have the following permissions silently granted by the admin:
- Location (ACCESS_BACKGROUND_LOCATION, ACCESS_COARSE_LOCATION, ACCESS_FINE_LOCATION).
- Camera (CAMERA)
- Microphone (RECORD_AUDIO)
- Body sensor (BODY_SENSORS)
- Physical activity (ACTIVITY_RECOGNITION)
If device implementations provide a user affordance to choose which apps can draw on top of other apps with an activity that handles the ACTION_MANAGE_OVERLAY_PERMISSION
intent, they:
- [C-2-1] MUST ensure that all activities with intent filters for the
ACTION_MANAGE_OVERLAY_PERMISSION
intent have the same UI screen, regardless of the initiating app or any information it provides.
If device implementations report android.software.device_admin, they:
- [C-3-1] MUST show a disclaimer during fully managed device setup (device owner setup) stating that the IT admin will have the ability to allow apps to control settings on the phone including microphone, camera and location, with options for user to continue setup or exit setup UNLESS the admin has opted out of control of permissions on the device.
If device implementations pre-install any packages that hold any of the System UI Intelligence , System Ambient Audio Intelligence , System Audio Intelligence , System Notification Intelligence , System Text Intelligence , or System Visual Intelligence roles, the packages:
- [C-4-1] MUST fulfill all requirements outlined for device implementations in section "9.8.6 Content Capture".
- [C-4-2] MUST NOT have android.permission.INTERNET permission. This is stricter than the STRONGLY RECOMMENDED listed in section 9.8.6.
- [C-4-3] MUST NOT bind to other apps, except for the following system apps: Bluetooth, Contacts, Media, Telephony, SystemUI, and components providing Internet APIs.This is stricter than the STRONGLY RECOMMENDED listed in section 9.8.6 .
9.2. UID and Process Isolation
Device implementations:
- [C-0-1] MUST support the Android application sandbox model, in which each application runs as a unique Unixstyle UID and in a separate process.
- [C-0-2] MUST support running multiple applications as the same Linux user ID, provided that the applications are properly signed and constructed, as defined in the Security and Permissions reference .
9.3. Filesystem Permissions
Device implementations:
- [C-0-1] MUST support the Android file access permissions model as defined in the Security and Permissions reference .
9.4. Alternate Execution Environments
Device implementations MUST keep consistency of the Android security and permission model, even if they include runtime environments that execute applications using some other software or technology than the Dalvik Executable Format or native code. به عبارت دیگر:
[C-0-1] Alternate runtimes MUST themselves be Android applications, and abide by the standard Android security model, as described elsewhere in section 9 .
[C-0-2] Alternate runtimes MUST NOT be granted access to resources protected by permissions not requested in the runtime's
AndroidManifest.xml
file via the <uses-permission
> mechanism.[C-0-3] Alternate runtimes MUST NOT permit applications to make use of features protected by Android permissions restricted to system applications.
[C-0-4] Alternate runtimes MUST abide by the Android sandbox model and installed applications using an alternate runtime MUST NOT reuse the sandbox of any other app installed on the device, except through the standard Android mechanisms of shared user ID and signing certificate .
[C-0-5] Alternate runtimes MUST NOT launch with, grant, or be granted access to the sandboxes corresponding to other Android applications.
[C-0-6] Alternate runtimes MUST NOT be launched with, be granted, or grant to other applications any privileges of the superuser (root), or of any other user ID.
[C-0-7] When the
.apk
files of alternate runtimes are included in the system image of device implementations, it MUST be signed with a key distinct from the key used to sign other applications included with the device implementations.[C-0-8] When installing applications, alternate runtimes MUST obtain user consent for the Android permissions used by the application.
[C-0-9] When an application needs to make use of a device resource for which there is a corresponding Android permission (such as Camera, GPS, etc.), the alternate runtime MUST inform the user that the application will be able to access that resource.
[C-0-10] When the runtime environment does not record application capabilities in this manner, the runtime environment MUST list all permissions held by the runtime itself when installing any application using that runtime.
Alternate runtimes SHOULD install apps via the
PackageManager
into separate Android sandboxes (Linux user IDs, etc.).Alternate runtimes MAY provide a single Android sandbox shared by all applications using the alternate runtime.
9.5. Multi-User Support
Android includes support for multiple users and provides support for full user isolation and clone user profiles with partial isolation(ie single additional user profile of type android.os.usertype.profile.CLONE
).
- Device implementations MAY but SHOULD NOT enable multi-user if they use removable media for primary external storage.
If device implementations include support for multiple users, they:
- [C-1-2] MUST, for each user, implement a security model consistent with the Android platform security model as defined in Security and Permissions reference document in the APIs.
- [C-1-3] MUST have separate and isolated shared application storage (aka
/sdcard
) directories for each user instance. - [C-1-4] MUST ensure that applications owned by and running on behalf a given user cannot list, read, or write to the files owned by any other user, even if the data of both users are stored on the same volume or filesystem.
- [C-1-5] MUST encrypt the contents of the SD card when multiuser is enabled using a key stored only on non-removable media accessible only to the system if device implementations use removable media for the external storage APIs. As this will make the media unreadable by a host PC, device implementations will be required to switch to MTP or a similar system to provide host PCs with access to the current user's data.
If device implementations include support for multiple users, then for all users except users specifically created for running dual instances of the same app, they:
- [C-2-1] MUST have separate and isolated shared application storage (aka /sdcard) directories for each user instance.
- [C-2-2] MUST ensure that applications owned by and running on behalf of a given user cannot list, read, or write to the files owned by any other user, even if the data of both users are stored on the same volume or filesystem.
Device implementations MAY create a single additional user profile of type android.os.usertype.profile.CLONE
against the primary user (and only against the primary user) for the purpose of running dual instances of the same app. These dual instances share partially isolated storage, are presented to the end user in the launcher at the same time and appear in the same recents view. For example, this could be used to support the user installing two separate instances of a single app on a dual-SIM device.
If device implementations create the additional user profile discussed above, then they:
- [C-3-1] MUST only provide access to storage or data that is either already accessible to the parent user profile or is directly owned by this additional user profile.
- [C-3-2] MUST NOT have this as a work profile.
- [C-3-3] MUST have isolated private app data directories from the parent user account.
- [C-3-4] MUST NOT allow the additional user profile to be created if there is a Device Owner provisioned (see section 3.9.1) or allow a Device Owner to be provisioned without removing the additional user profile first.
9.6. Premium SMS Warning
Android includes support for warning users of any outgoing premium SMS message . Premium SMS messages are text messages sent to a service registered with a carrier that may incur a charge to the user.
If device implementations declare support for android.hardware.telephony
, they:
- [C-1-1] MUST warn users before sending a SMS message to numbers identified by regular expressions defined in
/data/misc/sms/codes.xml
file in the device. The upstream Android Open Source Project provides an implementation that satisfies this requirement.
9.7. ویژگی های امنیتی
Device implementations MUST ensure compliance with security features in both the kernel and platform as described below.
The Android Sandbox includes features that use the Security-Enhanced Linux (SELinux) mandatory access control (MAC) system, seccomp sandboxing, and other security features in the Linux kernel. Device implementations:
- [C-0-1] MUST maintain compatibility with existing applications, even when SELinux or any other security features are implemented below the Android framework.
- [C-0-2] MUST NOT have a visible user interface when a security violation is detected and successfully blocked by the security feature implemented below the Android framework, but MAY have a visible user interface when an unblocked security violation occurs resulting in a successful بهره برداری کند.
- [C-0-3] MUST NOT make SELinux or any other security features implemented below the Android framework configurable to the user or app developer.
- [C-0-4] MUST NOT allow an application that can affect another application through an API (such as a Device Administration API) to configure a policy that breaks compatibility.
- [C-0-5] MUST split the media framework into multiple processes so that it is possible to more narrowly grant access for each process as described in the Android Open Source Project site.
- [C-0-6] MUST implement a kernel application sandboxing mechanism which allows filtering of system calls using a configurable policy from multithreaded programs. The upstream Android Open Source Project meets this requirement through enabling the seccomp-BPF with threadgroup synchronization (TSYNC) as described in the Kernel Configuration section of source.android.com .
Kernel integrity and self-protection features are integral to Android security. Device implementations:
- [C-0-7] MUST implement kernel stack buffer overflow protection mechanisms. Examples of such mechanisms are
CC_STACKPROTECTOR_REGULAR
andCONFIG_CC_STACKPROTECTOR_STRONG
. - [C-0-8] MUST implement strict kernel memory protections where executable code is read-only, read-only data is non-executable and non-writable, and writable data is non-executable (eg
CONFIG_DEBUG_RODATA
orCONFIG_STRICT_KERNEL_RWX
). - [C-0-9] MUST implement static and dynamic object size bounds checking of copies between user-space and kernel-space (eg
CONFIG_HARDENED_USERCOPY
) on devices originally shipping with API level 28 or higher. - [C-0-10] MUST NOT execute user-space memory when executing in the kernel mode (eg hardware PXN, or emulated via
CONFIG_CPU_SW_DOMAIN_PAN
orCONFIG_ARM64_SW_TTBR0_PAN
) on devices originally shipping with API level 28 or higher. - [C-0-11] MUST NOT read or write user-space memory in the kernel outside of normal usercopy access APIs (eg hardware PAN, or emulated via
CONFIG_CPU_SW_DOMAIN_PAN
orCONFIG_ARM64_SW_TTBR0_PAN
) on devices originally shipping with API level 28 or higher. - [C-0-12] MUST implement kernel page table isolation if the hardware is vulnerable to CVE-2017-5754 on all devices originally shipping with API level 28 or higher (eg
CONFIG_PAGE_TABLE_ISOLATION
orCONFIG_UNMAP_KERNEL_AT_EL0
). - [C-0-13] MUST implement branch prediction hardening if the hardware is vulnerable to CVE-2017-5715 on all devices originally shipping with API level 28 or higher (eg
CONFIG_HARDEN_BRANCH_PREDICTOR
). - [C-SR-1] STRONGLY RECOMMENDED to keep kernel data which is written only during initialization marked read-only after initialization (eg
__ro_after_init
). [C-SR-2] Are STRONGLY RECOMMENDED to randomize the layout of the kernel code and memory, and to avoid exposures that would compromise the randomization (eg
CONFIG_RANDOMIZE_BASE
with bootloader entropy via the/chosen/kaslr-seed Device Tree node
orEFI_RNG_PROTOCOL
) .[C-SR-3] Are STRONGLY RECOMMENDED to enable control flow integrity (CFI) in the kernel to provide additional protection against code-reuse attacks (eg
CONFIG_CFI_CLANG
andCONFIG_SHADOW_CALL_STACK
).[C-SR-4] Are STRONGLY RECOMMENDED not to disable Control-Flow Integrity (CFI), Shadow Call Stack (SCS) or Integer Overflow Sanitization (IntSan) on components that have it enabled.
[C-SR-5] Are STRONGLY RECOMMENDED to enable CFI, SCS, and IntSan for any additional security-sensitive userspace components as explained in CFI and IntSan .
[C-SR-6] Are STRONGLY RECOMMENDED to enable stack initialization in the kernel to prevent uses of uninitialized local variables (
CONFIG_INIT_STACK_ALL
orCONFIG_INIT_STACK_ALL_ZERO
). Also, device implementations SHOULD NOT assume the value used by the compiler to initialize the locals.[C-SR-7] Are STRONGLY RECOMMENDED to enable heap initialization in the kernel to prevent uses of uninitialized heap allocations (
CONFIG_INIT_ON_ALLOC_DEFAULT_ON
) and they SHOULD NOT assume the value used by the kernel to initialize those allocations.
If device implementations use a Linux kernel that is capable of supporting SELinux, they:
- [C-1-1] MUST implement SELinux.
- [C-1-2] MUST set SELinux to global enforcing mode.
- [C-1-3] MUST configure all domains in enforcing mode. No permissive mode domains are allowed, including domains specific to a device/vendor.
- [C-1-4] MUST NOT modify, omit, or replace the neverallow rules present within the system/sepolicy folder provided in the upstream Android Open Source Project (AOSP) and the policy MUST compile with all neverallow rules present, for both AOSP SELinux domains as well as device/vendor specific domains.
- [C-1-5] MUST run third-party applications targeting API level 28 or higher in per-application SELinux sandboxes with per-app SELinux restrictions on each application's private data directory.
- SHOULD retain the default SELinux policy provided in the system/sepolicy folder of the upstream Android Open Source Project and only further add to this policy for their own device-specific configuration.
If device implementations use kernel other than Linux or Linux without SELinux, they:
- [C-2-1] MUST use a mandatory access control system that is equivalent to SELinux.
If device implementations use I/O devices capable of DMA, they:
- [C-SR-8] Are STRONGLY RECOMMENDED to isolate each I/O device capable of DMA, using an IOMMU (egthe ARM SMMU).
Android contains multiple defense-in-depth features that are integral to device security. In addition, Android focuses on reducing key classes of common bugs that contribute to poor quality and security.
In order to reduce memory bugs, device implementations:
- [C-SR-9] Are STRONGLY RECOMMENDED to be tested using userspace memory error detection tools like MTE for ARMv9 devices, HWASan for ARMv8+ devices or ASan for other device types.
- [C-SR-10] Are STRONGLY RECOMMENDED to be tested using kernel memory error detection tools like KASAN (CONFIG_KASAN, CONFIG_KASAN_HW_TAGS for ARMv9 devices, CONFIG_KASAN_SW_TAGS for ARMv8 devices or CONFIG_KASAN_GENERIC for other device types).
- [C-SR-11] Are STRONGLY RECOMMENDED to be using memory error detection tools in production like MTE, GWP-ASan and KFENCE.
If device implementations use an Arm TrustZone-based TEE, they:
- [C-SR-12] Are STRONGLY RECOMMENDED to use a standard protocol for memory sharing, between Android and the TEE, like Arm Firmware Framework for Armv8-A (FF-A).
- [C-SR-13] Are STRONGLY RECOMMENDED to restrict trusted applications to only accessing memory which has been explicitly shared with them via the above protocol. If the device has support for the Arm S-EL2 exception level, this should be enforced by the secure partition manager. Otherwise, this should be enforced by the TEE OS.
9.8. حریم خصوصی
9.8.1. تاریخچه استفاده
Android stores the history of the user's choices and manages such history by UsageStatsManager .
Device implementations:
- [C-0-1] MUST keep a reasonable retention period of such user history.
- [C-SR-1] Are STRONGLY RECOMMENDED to keep the 14 days retention period as configured by default in the AOSP implementation.
Android stores the system events using the StatsLog
identifiers, and manages such history via the StatsManager
and the IncidentManager
System API.
Device implementations:
- [C-0-2] MUST only include the fields marked with
DEST_AUTOMATIC
in the incident report created by the System API classIncidentManager
. - [C-0-3] MUST not use the system event identifiers to log any other event than what is described in the
StatsLog
SDK documents. If additional system events are logged, they MAY use a different atom identifier in the range between 100,000 and 200,000.
9.8.2. در حال ضبط
Device implementations:
- [C-0-1] MUST NOT preload or distribute software components out-of-box that send the user's private information (eg keystrokes, text displayed on the screen, bugreport) off the device without the user's consent or clear ongoing notifications.
- [C-0-2] MUST display and obtain explicit user consent allowing any sensitive information that is displayed on the user's screen to be captured whenever screen casting or screen recording is enabled via
MediaProjection
or proprietary APIs. MUST NOT provide users an affordance to disable future display of the user consent. - [C-0-3] MUST have an ongoing notification to the user while screen casting or screen recording is enabled. AOSP meets this requirement by showing an ongoing notification icon in the status bar.
If device implementations include functionality in the system that either captures the contents displayed on the screen and/or records the audio stream played on the device other than via the System API ContentCaptureService
, or other proprietary means described in Section 9.8.6 Content Capture , they :
- [C-1-1] MUST have an ongoing notification to the user whenever this functionality is enabled and actively capturing/recording.
If device implementations include a component enabled out-of-box, capable of recording ambient audio and/or record the audio played on the device to infer useful information about user's context, they:
- [C-2-1] MUST NOT store in persistent on-device storage or transmit off the device the recorded raw audio or any format that can be converted back into the original audio or a near facsimile, except with explicit user consent.
A “microphone indicator” refers to a view on screen, which is constantly visible to the user and cannot be obscured, which users understand as a microphone is in use(through unique text, color, icon, or some combination).
A “camera indicator” refers to a view on screen, which is constantly visible to the user and cannot be obscured, which users understand as a camera is in use (through unique text, color, icon, or some combination).
After the first one second displayed, an indicator can change visually, such as becoming smaller, and is not required to show as originally presented and understood.
The microphone indicator may be merged with an actively displayed camera indicator, provided that text, icons, or colors indicate to the user that microphone use has begun.
The camera indicator may be merged with an actively displayed microphone indicator, provided that text, icons, or colors indicate to the user that the camera use has begun.
If device implementations declare android.hardware.microphone
, they:
- [C-SR-1] Are STRONGLY RECOMMENDED to display microphone indicator when an app is accessing audio data from the microphone, but not when the microphone is only accessed by
HotwordDetectionService
,SOURCE_HOTWORD
,ContentCaptureService
, or app(s) holding the roles called out in Section 9.1 Permissions with CDD identifier [C-3-X]. . - [C-SR-2] Are STRONGLY RECOMMENDED to display the list of Recent and Active apps using microphone as returned from
PermissionManager.getIndicatorAppOpUsageData()
, along with any attribution messages associated with them. - [C-SR-3] Are STRONGLY RECOMMENDED to not hide the microphone indicator for system apps that have visible user interfaces or direct user interaction.
If device implementations declare android.hardware.camera.any
, they:
- [C-SR-4] Are STRONGLY RECOMMENDED to display camera indicator when an app is accessing live camera data, but not when the camera is only being accessed by app(s) holding the roles called out in Section 9.1 Permissions with CDD identifier [C-3-X].
- [C-SR-5] Are STRONGLY RECOMMENDED to display Recent and Active apps using camera as returned from
PermissionManager.getIndicatorAppOpUsageData()
, along with any attribution messages associated with them. - [C-SR-6] Are STRONGLY RECOMMENDED to not hide the camera indicator for system apps that have visible user interfaces or direct user interaction.
9.8.3. قابلیت اتصال
If device implementations have a USB port with USB peripheral mode support, they:
- [C-1-1] MUST present a user interface asking for the user's consent before allowing access to the contents of the shared storage over the USB port.
9.8.4. Network Traffic
Device implementations:
- [C-0-1] MUST preinstall the same root certificates for the system-trusted Certificate Authority (CA) store as provided in the upstream Android Open Source Project.
- [C-0-2] MUST ship with an empty user root CA store.
- [C-0-3] MUST display a warning to the user indicating the network traffic may be monitored, when a user root CA is added.
If device traffic is routed through a VPN, device implementations:
- [C-1-1] MUST display a warning to the user indicating either:
- That network traffic may be monitored.
- That network traffic is being routed through the specific VPN application providing the VPN.
If device implementations have a mechanism, enabled out-of-box by default, that routes network data traffic through a proxy server or VPN gateway (for example, preloading a VPN service with android.permission.CONTROL_VPN
granted), they:
- [C-2-1] MUST ask for the user's consent before enabling that mechanism, unless that VPN is enabled by the Device Policy Controller via the
DevicePolicyManager.setAlwaysOnVpnPackage()
, in which case the user does not need to provide a separate consent, but MUST only be notified.
If device implementations implement a user affordance to toggle on the "always-on VPN" function of a 3rd-party VPN app, they:
- [C-3-1] MUST disable this user affordance for apps that do not support always-on VPN service in the
AndroidManifest.xml
file via setting theSERVICE_META_DATA_SUPPORTS_ALWAYS_ON
attribute tofalse
.
9.8.5. Device Identifiers
Device implementations:
- [C-0-1] MUST prevent access to the device serial number and, where applicable, IMEI/MEID, SIM serial number, and International Mobile Subscriber Identity (IMSI) from an app, unless it meets one of the following requirements:
- is a signed carrier app that is verified by device manufacturers.
- has been granted the
READ_PRIVILEGED_PHONE_STATE
permission. - has carrier privileges as defined in UICC Carrier Privileges .
- is a device owner or profile owner that has been granted the
READ_PHONE_STATE
permission. - (For SIM serial number/ICCID only) has the local regulations requirement that the app detect changes in the subscriber's identity.
9.8.6. Content Capture and App Search
Android, through the System API ContentCaptureService
, AugmentedAutofillService
, AppSearchGlobalManager.query
, or by other proprietary means, supports a mechanism for device implementations to capture the following application data interactions between the applications and the user:
- Text and graphics rendered on-screen, including but not limited to, notifications and assist data via
AssistStructure
API. - Media data, such as audio or video, recorded or played by the device.
- Input events (eg key, mouse, gesture, voice, video, and accessibility).
- Any other events that an application provides to the system via the
Content Capture
API or orAppSearchManager
API a similarly capable Android and proprietary API. - Any text or other data sent via the
TextClassifier API
to the System TextClassifier ie to the system service to understand the meaning of text, as well as generating predicted next actions based on the text. - Data indexed by the platform AppSearch implementation, including but not limited to text, graphics, media data or other similar data.
If device implementations capture the data above, they:
- [C-1-1] MUST encrypt all such data when stored in the device. This encryption MAY be carried out using Android File Based Encryption, or any of the ciphers listed as API version 26+ described in Cipher SDK .
- [C-1-2] MUST NOT back up either raw or encrypted data using Android backup methods or any other back up methods.
- [C-1-3] MUST only send all such data and the log of the device using a privacy-preserving mechanism. The privacy-preserving mechanism is defined as “those which allow only analysis in aggregate and prevent matching of logged events or derived outcomes to individual users”, to prevent any per-user data being introspectable (eg, implemented using a differential privacy technology such as
RAPPOR
). - [C-1-4] MUST NOT associate such data with any user identity (such as
Account
) on the device, except with explicit user consent each time the data is associated. - [C-1-5] MUST NOT share such data with other OS components that don't follow requirements outlined in the current section (9.8.6 Content Capture), except with explicit user consent every time it is shared.
- [C-1-6] MUST provide user affordance to erase such data that the
ContentCaptureService
or the proprietary means collects if the data is stored in any form on the device. - [C-1-7] MUST provide a user affordance to opt-out of the data, collected via AppSearch or proprietary means from being shown in android platform eg launcher.
- [C-SR-1] Are STRONGLY RECOMMENDED NOT to request the INTERNET permission.
- [C-SR-2] Are STRONGLY RECOMMENDED to only access the internet through structured APIs backed by publicly available open-source implementations.
If device implementations include a service that implements the System API ContentCaptureService
, AppSearchManager.index
, or any proprietary service that captures the data as described as above, they:
- [C-2-1] MUST NOT allow users to replace the services with a user-installable application or service and MUST only allow the preinstalled services to capture such data.
- [C-2-2] MUST NOT allow any apps other than the preinstalled services mechanism to be able to capture such data.
- [C-2-3] MUST provide user affordance to disable the services.
- [C-2-4] MUST NOT omit user affordance to manage Android permissions that are held by the services and follow Android permissions model as described in Section 9.1. Permission .
[C-SR-3] Are STRONGLY RECOMMENDED to keep the services separate from other system components(eg not binding the service or sharing process IDs) except for the following:
- Telephony, Contacts, System UI, and Media
Android, through SpeechRecognizer#onDeviceSpeechRecognizer()
provides ability to perform speech recognition on the device, without involving the network. Any implementation of on-device SpeechRecognizer MUST follow the policies outlined in this section.
9.8.7. Clipboard Access
Device implementations:
- [C-0-1] MUST NOT return a clipped data on the clipboard (eg via the
ClipboardManager
API) unless the app is the default IME or is the app that currently has focus.
9.8.8. مکان
Location includes information in the Android Location class( such as Latitude, Longitude, Altitude), as well as identifiers that can be converted to Location. Location can be as fine as DGPS (Differential Global Positioning System) or as coarse as country level locations (like the country code location - MCC - Mobile Country Code).
The following is a list of location types that either directly derive a user's location or can be converted to a user's location. This is not a comprehensive list, but should be used as an example on what Location can directly or indirectly be derived from:
- GPS/GNSS/DGPS/PPP
- Global Positioning Solution or Global Navigation Satellite System or Differential Global Positioning Solution
- This also includes Raw GNSS Measurements and GNSS Status
- Fine Location can be derived from the Raw GNSS Measurements
- Wireless Technologies with unique identifiers such as:
- WiFi access points (MAC, BSSID, Name, or SSID)
- Bluetooth/BLE (MAC, BSSID, Name, or SSID)
- UWB (MAC, BSSID, Name, or SSID)
- Cell Tower ID (3G, 4G, 5G… Iincluding all future Cellular Modem technologies that have unique identifiers)
As a primary point of reference, see the Android APIs which require ACCESS_FINE_Location or ACCESS_COARSE_Location permissions.
Device implementations:
- [C-0-1] MUST NOT turn on/off device location setting and Wi-Fi/Bluetooth scanning settings without explicit user consent or user initiation.
- [C-0-2] MUST provide the user affordance to access location related information including recent location requests, app level permissions and usage of Wi-Fi/Bluetooth scanning for determining location.
- [C-0-3] MUST ensure that the application using Emergency Location Bypass API [LocationRequest.setLocationSettingsIgnored()] is a user initiated emergency session (eg dial 911 or text to 911). For Automotive however, a vehicle MAY initiate an emergency session without active user interaction in the case a crash/accident is detected (eg to satisfy eCall requirements).
- [C-0-4] MUST preserve the Emergency Location Bypass API's ability to bypass device location settings without changing the settings.
- [C-0-5] MUST schedule a notification that reminds the user after an app in the background has accessed their location using the [
ACCESS_BACKGROUND_LOCATION
] permission.
9.8.9. Installed apps
Android apps targeting API level 30 or above cannot see details about other installed apps by default (see Package visibility in the Android SDK documentation).
Device implementations:
- [C-0-1] MUST NOT expose to any app targeting API level 30 or above details about any other installed app, unless the app is already able to see details about the other installed app through the managed APIs. This includes but is not limited to details exposed by any custom APIs added by the device implementer, or accessible via the filesystem.
- [C-0-2] MUST NOT give to any app, read or write access to files in any other app's dedicated, app-specific directory within external storage. The only exceptions are as follows:
- The external storage provider authority (eg apps like DocumentsUI).
- Download Provider which uses the “downloads” provider authority for downloading files to app storage.
- Platform-signed media transfer protocol (MTP) apps which use the privileged permission ACCESS_MTP to enable transferring files to another device.
- Apps which install other apps and have the permission INSTALL_PACKAGES can access only “obb” directories for the purpose of managing APK expansion files .
9.8.10. Connectivity Bug Report
If device implementations declare the android.hardware.telephony
feature flag, they:
- [C-1-1] MUST support generating connectivity bug reports via
BUGREPORT_MODE_TELEPHONY
with BugreportManager. - [C-1-2] MUST obtain user consent every time
BUGREPORT_MODE_TELEPHONY
is used to generate a report and MUST NOT prompt the user to consent to all future requests from the application. - [C-1-3] MUST NOT return the generated report to the requesting app without explicit user consent.
- [C-1-4] Reports generated using
BUGREPORT_MODE_TELEPHONY
MUST contain at least the following information:-
TelephonyDebugService
dump -
TelephonyRegistry
dump -
WifiService
dump -
ConnectivityService
dump - A dump of the calling package's
CarrierService
instance (if bound) - Radio log buffer
-
- [C-1-5] MUST NOT include the following in the generated reports:
- Any kind of information that isn't directly related to connectivity debugging.
- Any kind of user-installed application traffic logs or detailed profiles of user-installed applications/packages (UIDs are okay, package names are not).
- MAY include additional information that is not associated with any user identity. (eg vendor logs).
If device implementations include additional information (eg vendor logs) in bug reports and that information has privacy/security/battery/storage/memory impact, they:
- [C-SR-1] Are STRONGLY RECOMMENDED to have a developer setting defaulted to disabled. The AOSP reference implementation meets this by providing the
Enable verbose vendor logging
option in developer settings to include additional device-specific vendor logs in the bug reports.
9.8.11. Data blobs sharing
Android, through BlobStoreManager allows apps to contribute data blobs to the System to be shared with a selected set of apps.
If device implementations support shared data blobs as described in the SDK documentation , they:
- [C-1-1] MUST NOT share data blobs belonging to apps beyond what they intended to allow (ie the scope of default access and the other access modes that can be specified using BlobStoreManager.session#allowPackageAccess() , BlobStoreManager.session#allowSameSignatureAccess() , or BlobStoreManager.session#allowPublicAccess() MUST NOT be modified). The AOSP reference implementation meets these requirements.
- [C-1-2] MUST NOT send off device or share with other apps the secure hashes of data blobs (which are used to control access).
9.8.12. Music Recognition
Android, through the System API MusicRecognitionManager, supports a mechanism for device implementations to request music recognition, given an audio record, and delegate the music recognition to a privileged app implementing the MusicRecognitionService API.
If device implementations include a service that implements the System API MusicRecognitionManager or any proprietary service that streams audio data as described as above, they:
- [C-1-1] MUST enforce that the caller of MusicRecognitionManager holds the
MANAGE_MUSIC_RECOGNITION
permission - [C-1-2] MUST enforce that a single, pre-installed, music recognition application implements MusicRecognitionService.
- [C-1-3] MUST NOT allow users to replace the MusicRecognitionManagerService or MusicRecognitionService with a user-installable application or service.
- [C-1-4] MUST ensure that when MusicRecognitionManagerService accesses the audio record and forwards it to the application implementing the MusicRecognitionService, the audio access is tracked via invocations of AppOpsManager.noteOp / startOp .
If device implementations of MusicRecognitionManagerService or MusicRecognitionService store any audio data captured, they:
- [C-2-1] MUST NOT store any raw audio or audio fingerprints on disk at all, or in memory for longer than 14 days.
- [C-2-2] MUST NOT share such data beyond the MusicRecognitionService, except with explicit user consent every time it is shared.
9.8.13. SensorPrivacyManager
If device implementations provide the user a software affordance to turn off the camera and/or microphone input for the device implementation, they:
- [C-1-1] MUST accurately return 'true' for the relevant supportsSensorToggle() API method.
- [C-1-2] MUST, when an app tries to access a blocked microphone or camera, present the user with a non-dismissable user affordance that clearly indicates that the sensor is blocked and requires a choice to continue blocking or unblock as per the AOSP implementation which meets this requirement.
- [C-1-3] MUST only pass blank (or fake) camera and audio data to apps and not report an error code due to the user not turning on the camera nor microphone via the user affordance presented per [C-1-2] above.
9.9. Data Storage Encryption
All devices MUST meet the requirements of section 9.9.1. Devices which launched on an API level earlier than that of this document are exempted from the requirements of sections 9.9.2 and 9.9.3; instead they MUST meet the requirements in section 9.9 of the Android Compatibility Definition document corresponding to the API level on which the device launched.
9.9.1. Direct Boot
Device implementations:
[C-0-1] MUST implement the Direct Boot mode APIs even if they do not support Storage Encryption.
[C-0-2] The
ACTION_LOCKED_BOOT_COMPLETED
andACTION_USER_UNLOCKED
Intents MUST still be broadcast to signal Direct Boot aware applications that Device Encrypted (DE) and Credential Encrypted (CE) storage locations are available for user.
9.9.2. Encryption requirements
Device implementations:
- [C-0-1] MUST encrypt the application private data (
/data
partition), as well as the application shared storage partition (/sdcard
partition) if it is a permanent, non-removable part of the device. - [C-0-2] MUST enable the data storage encryption by default at the time the user has completed the out-of-box setup experience.
[C-0-3] MUST meet the above data storage encryption requirement by implementing one of the following two encryption methods:
- File Based Encryption (FBE) and Metadata Encryption as described in section 9.9.3.1.
- Per-User Block-Level Encryption as described in section 9.9.3.2.
9.9.3. روش های رمزگذاری
If device implementations are encrypted, they:
- [C-1-1] MUST boot up without challenging the user for credentials and allow Direct Boot aware apps to access to the Device Encrypted (DE) storage after the
ACTION_LOCKED_BOOT_COMPLETED
message is broadcasted. - [C-1-2] MUST only allow access to Credential Encrypted (CE) storage after the user has unlocked the device by supplying their credentials (eg. passcode, pin, pattern or fingerprint) and the
ACTION_USER_UNLOCKED
message is broadcasted. - [C-1-13] MUST NOT offer any method to unlock the CE protected storage without either the user-supplied credentials, a registered escrow key or a resume on reboot implementation meeting the requirements in section 9.9.4 .
- [C-1-4] MUST use Verified Boot.
9.9.3.1. File Based Encryption with Metadata Encryption
If device implementations use File Based Encryption with Metadata Encryption, they:
- [C-1-5] MUST encrypt file contents and filesystem metadata using AES-256-XTS or Adiantum. AES-256-XTS refers to the Advanced Encryption Standard with a 256-bit cipher key length, operated in XTS mode; the full length of the key is 512 bits. Adiantum refers to Adiantum-XChaCha12-AES, as specified at https://github.com/google/adiantum. Filesystem metadata is data such as file sizes, ownership, modes, and extended attributes (xattrs).
- [C-1-6] MUST encrypt file names using AES-256-CBC-CTS or Adiantum.
- [C-1-12] If the device has Advanced Encryption Standard (AES) instructions (such as ARMv8 Cryptography Extensions on ARM-based devices, or AES-NI on x86-based devices) then the AES-based options above for file name, file contents, and filesystem metadata encryption MUST be used, not Adiantum.
- [C-1-13] MUST use a cryptographically strong and non-reversible key derivation function (eg HKDF-SHA512) to derive any needed subkeys (eg per-file keys) from the CE and DE keys. "Cryptographically strong and non-reversible" means that the key derivation function has a security strength of at least 256 bits and behaves as a pseudorandom function family over its inputs.
- [C-1-14] MUST NOT use the same File Based Encryption (FBE) keys or subkeys for different cryptographic purposes (eg for both encryption and key derivation, or for two different encryption algorithms).
- [C-1-15] MUST ensure that all non-deleted blocks of encrypted file contents on persistent storage were encrypted using combinations of encryption key and initialization vector (IV) that depend on both the file and the offset within the file. In addition, all such combinations MUST be distinct, except where the encryption is done using inline encryption hardware that only supports an IV length of 32 bits.
- [C-1-16] MUST ensure that all non-deleted encrypted filenames on persistent storage in distinct directories were encrypted using distinct combinations of encryption key and initialization vector (IV).
[C-1-17] MUST ensure that all encrypted filesystem metadata blocks on persistent storage were encrypted using distinct combinations of encryption key and initialization vector (IV).
Keys protecting CE and DE storage areas and filesystem metadata:
- [C-1-7] MUST be cryptographically bound to a hardware-backed Keystore. This keystore MUST be bound to Verified Boot and the device's hardware root of trust.
- [C-1-8] CE keys MUST be bound to a user's lock screen credentials.
- [C-1-9] CE keys MUST be bound to a default passcode when the user has not specified lock screen credentials.
- [C-1-10] MUST be unique and distinct, in other words no user's CE or DE key matches any other user's CE or DE keys.
- [C-1-11] MUST use the mandatorily supported ciphers, key lengths and modes.
- [C-1-12] MUST be securely erased during bootloader unlock and lock as described here .
SHOULD make preinstalled essential apps (eg Alarm, Phone, Messenger) Direct Boot aware.
The upstream Android Open Source project provides a preferred implementation of File Based Encryption based on the Linux kernel "fscrypt" encryption feature, and of Metadata Encryption based on the Linux kernel "dm-default-key" feature.
9.9.3.2. Per-User Block-Level Encryption
If device implementations use per-user block-level encryption, they:
- [C-1-1] MUST enable multi-user support as described in section 9.5.
- [C-1-2] MUST provide per-user partitions, either using raw partitions or logical volumes.
- [C-1-3] MUST use unique and distinct encryption keys per-user for encryption of the underlying block devices.
[C-1-4] MUST use AES-256-XTS for block-level encryption of the user partitions.
The keys protecting the per-user block-level encrypted devices:
- [C-1-5] MUST be cryptographically bound to a hardware-backed Keystore. This keystore MUST be bound to Verified Boot and the device's hardware root of trust.
- [C-1-6] MUST be bound to the corresponding user's lock screen credentials.
Per-user block-level encryption can be implemented using the Linux kernel "dm-crypt" feature over per-user partitions.
9.9.4. Resume on Reboot
Resume on Reboot allows unlocking the CE storage of all apps, including those that do not yet support Direct Boot, after a reboot initiated by an OTA. This feature enables users to receive notifications from installed apps after the reboot.
An implementation of Resume-on-Reboot must continue to ensure that when a device falls into an attacker's hands, it is extremely difficult for that attacker to recover the user's CE-encrypted data, even if the device is powered on, CE storage is unlocked, and the user has unlocked the device after receiving an OTA. For insider attack resistance, we also assume the attacker gains access to broadcast cryptographic signing keys.
به طور مشخص:
[C-0-1] CE storage MUST NOT be readable even for the attacker who physically has the device and then has these capabilities and limitations:
- Can use the signing key of any vendor or company to sign arbitrary messages.
- Can cause an OTA to be received by the device.
- Can modify the operation of any hardware (AP, flash etc) except as detailed below, but such modification involves a delay of at least an hour and a power cycle that destroys RAM contents.
- Cannot modify the operation of tamper-resistant hardware (eg Titan M).
- Cannot read the RAM of the live device.
- Cannot obtain the user's credential (PIN, pattern, password) or otherwise cause it to be entered.
By way of example, a device implementation that implements and complies with all of the descriptions found here will be compliant with [C-0-1].
9.10. Device Integrity
The following requirements ensure there is transparency to the status of the device integrity. Device implementations:
[C-0-1] MUST correctly report through the System API method
PersistentDataBlockManager.getFlashLockState()
whether their bootloader state permits flashing of the system image.[C-0-2] MUST support Verified Boot for device integrity.
If device implementations are already launched without supporting Verified Boot on an earlier version of Android and can not add support for this feature with a system software update, they MAY be exempted from the requirement.
Verified Boot is a feature that guarantees the integrity of the device software. If device implementations support the feature, they:
- [C-1-1] MUST declare the platform feature flag
android.software.verified_boot
. - [C-1-2] MUST perform verification on every boot sequence.
- [C-1-3] MUST start verification from an immutable hardware key that is the root of trust and go all the way up to the system partition.
- [C-1-4] MUST implement each stage of verification to check the integrity and authenticity of all the bytes in the next stage before executing the code in the next stage.
- [C-1-5] MUST use verification algorithms as strong as current recommendations from NIST for hashing algorithms (SHA-256) and public key sizes (RSA-2048).
- [C-1-6] MUST NOT allow boot to complete when system verification fails, unless the user consents to attempt booting anyway, in which case the data from any non-verified storage blocks MUST not be used.
- [C-1-7] MUST NOT allow verified partitions on the device to be modified unless the user has explicitly unlocked the bootloader.
- [C-SR-1] If there are multiple discrete chips in the device (eg radio, specialized image processor), the boot process of each of those chips is STRONGLY RECOMMENDED to verify every stage upon booting.
- [C-1-8] MUST use tamper-evident storage: for storing whether the bootloader is unlocked. Tamper-evident storage means that the bootloader can detect if the storage has been tampered with from inside Android.
- [C-1-9] MUST prompt the user, while using the device, and require physical confirmation before allowing a transition from bootloader locked mode to bootloader unlocked mode.
- [C-1-10] MUST implement rollback protection for partitions used by Android (eg boot, system partitions) and use tamper-evident storage for storing the metadata used for determining the minimum allowable OS version.
- [C-1-11] MUST securely erase all user data during bootloader unlock and lock, as per '9.12. Data Deletion' (including the userdata partition and any NVRAM spaces).
- [C-SR-2] Are STRONGLY RECOMMENDED to verify all privileged app APK files with a chain of trust rooted in partitions protected by Verified Boot.
- [C-SR-3] Are STRONGLY RECOMMENDED to verify any executable artifacts loaded by a privileged app from outside its APK file (such as dynamically loaded code or compiled code) before executing them or STRONGLY RECOMMENDED not to execute them at all.
- SHOULD implement rollback protection for any component with persistent firmware (eg modem, camera) and SHOULD use tamper-evident storage for storing the metadata used for determining the minimum allowable version.
If device implementations are already launched without supporting C-1-8 through C-1-11 on an earlier version of Android and can not add support for these requirements with a system software update, they MAY be exempted from the requirements.
The upstream Android Open Source Project provides a preferred implementation of this feature in the external/avb/
repository, which can be integrated into the bootloader used for loading Android.
Device implementations:
- [C-0-3] MUST support cryptographically verifying file content against a trusted key without reading the whole file.
- [C-0-4] MUST NOT allow the read requests on a protected file to succeed when the read content do not verify against a trusted key.
If device implementations are already launched without the ability to verify file content against a trusted key on an earlier Android version and can not add support for this feature with a system software update, they MAY be exempted from the requirement. The upstream Android Open Source project provides a preferred implementation of this feature based on the Linux kernel fs-verity feature.
Device implementations:
- [C-SR-4] Are STRONGLY RECOMMENDED to support the Android Protected Confirmation API .
If device implementations support the Android Protected Confirmation API they:
[C-3-1] MUST report
true
for theConfirmationPrompt.isSupported()
API.[C-3-2] MUST ensure that code running in the Android OS including its kernel, malicious or otherwise, cannot generate a positive response without user interaction.
[C-3-3] MUST ensure that the user has been able to review and approve the prompted message even in the event that the Android OS, including its kernel, is compromised.
9.11. Keys and Credentials
The Android Keystore System allows app developers to store cryptographic keys in a container and use them in cryptographic operations through the KeyChain API or the Keystore API . Device implementations:
- [C-0-1] MUST allow at least 8,192 keys to be imported or generated.
- [C-0-2] The lock screen authentication MUST implement a time interval between failed attempts. With n as the failed attempt count, the time interval MUST be at least 30 seconds for 9 < n < 30. For n > 29, the time interval value MUST be at least 30*2^floor((n-30)/10)) seconds or at least 24 hours, whichever is smaller.
- SHOULD not limit the number of keys that can be generated
When the device implementation supports a secure lock screen, it:
- [C-1-1] MUST back up the keystore implementation with an isolated execution environment.
- [C-1-2] MUST have implementations of RSA, AES, ECDSA and HMAC cryptographic algorithms and MD5, SHA1, and SHA-2 family hash functions to properly support the Android Keystore system's supported algorithms in an area that is securely isolated from the code running on the kernel and above. Secure isolation MUST block all potential mechanisms by which kernel or userspace code might access the internal state of the isolated environment, including DMA. The upstream Android Open Source Project (AOSP) meets this requirement by using the Trusty implementation, but another ARM TrustZone-based solution or a third-party reviewed secure implementation of a proper hypervisor-based isolation are alternative options.
- [C-1-3] MUST perform the lock screen authentication in the isolated execution environment and allow the authentication-bound keys to be used only after successful authentication. Lock screen credentials MUST be stored in a way that allows only the isolated execution environment to perform lock screen authentication. The upstream Android Open Source Project provides the Gatekeeper Hardware Abstraction Layer (HAL) and Trusty, which can be used to satisfy this requirement.
- [C-1-4] MUST support key attestation where the attestation signing key is protected by secure hardware and signing is performed in secure hardware. The attestation signing keys MUST be shared across large enough number of devices to prevent the keys from being used as device identifiers. One way of meeting this requirement is to share the same attestation key unless at least 100,000 units of a given SKU are produced. If more than 100,000 units of an SKU are produced, a different key MAY be used for each 100,000 units.
Note that if a device implementation is already launched on an earlier Android version, such a device is exempted from the requirement to have a keystore backed by an isolated execution environment and support the key attestation, unless it declares the android.hardware.fingerprint
feature which requires a keystore backed by an isolated execution environment.
- [C-1-5] MUST allow the user to choose the Sleep timeout for transition from the unlocked to the locked state, with a minimum allowable timeout up to 15 seconds. Automotive devices, that lock the screen whenever the head unit is turned off or the user is switched, MAY NOT have the Sleep timeout configuration.
- [C-1-6] MUST support one of the following:
- IKeymasterDevice 3.0,
- IKeymasterDevice 4.0,
- IKeymasterDevice 4.1, or
- IKeyMintDevice version 1.
- [C-SR-1] Is STRONGLY RECOMMENDED to support IKeyMintDevice version 1.
9.11.1. Secure Lock Screen and Authentication
The AOSP implementation follows a tiered authentication model where a knowledge-factory based primary authentication can be backed by either a secondary strong biometric, or by weaker tertiary modalities.
Device implementations:
- [C-SR-1] Are STRONGLY RECOMMENDED to set only one of the following as the primary authentication method:
- A numerical PIN
- An alphanumerical password
- A swipe pattern on a grid of exactly 3x3 dots
Note that the above authentication methods are referred as the recommended primary authentication methods in this document.
If device implementations add or modify the recommended primary authentication methods and use a new authentication method as a secure way to lock the s