自 2025 年 3 月 27 日起，我們建議您使用 android-latest-release 而非 aosp-main 建構及貢獻 AOSP。詳情請參閱「Android 開放原始碼計畫變更」。
音訊回送連接器
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
下圖和相片顯示耳機連接器的音訊迴路 連接器。Chrome 硬體團隊設計這個電路和插頭，用於功能測試；不過，它還有許多其他用途。Android 音訊團隊會透過這項功能，透過輸出端傳送已編碼的訊號，然後在輸入端尋找相符的訊號，以便測量往返音訊延遲時間。這兩者之間的時間就是輸入加上輸出延遲的總和。這種方法會用於 OboeTester 和 CTS Verifier。
您可以向 PassMark Software 索取以下電路為基礎的迴送式 Dongle。這並非推薦或認可。Google 與 PassMark 之間沒有任何商業關係。
電路
圖 1.電路圖
為確保輸出訊號不會造成麥克風輸入過載，我們將其降低約 20dB。電阻負載會告知麥克風極性開關，音訊迴路 dongle 是 US/CTIA 針腳排列的 Tip Ring Ring Shield (TRRS) 插頭。
已組裝
圖 2. 已組裝
這個頁面中的內容和程式碼範例均受《內容授權》中的授權所規範。Java 與 OpenJDK 是 Oracle 和/或其關係企業的商標或註冊商標。
上次更新時間：2025-02-27 (世界標準時間)。
[[["容易理解","easyToUnderstand","thumb-up"],["確實解決了我的問題","solvedMyProblem","thumb-up"],["其他","otherUp","thumb-up"]],[["缺少我需要的資訊","missingTheInformationINeed","thumb-down"],["過於複雜/步驟過多","tooComplicatedTooManySteps","thumb-down"],["過時","outOfDate","thumb-down"],["翻譯問題","translationIssue","thumb-down"],["示例/程式碼問題","samplesCodeIssue","thumb-down"],["其他","otherDown","thumb-down"]],["上次更新時間：2025-02-27 (世界標準時間)。"],[],[],null,["# Audio loopback dongle\n\nThe diagram and photo below show an audio loopback\n[dongle](http://en.wikipedia.org/wiki/Dongle)\nfor the\n[headset connector](http://en.wikipedia.org/wiki/Phone_connector_(audio)).\nThe Chrome hardware team designed this circuit and plug for functional testing;\nhowever it has many other uses too. The Android audio team uses it to measure\n[round-trip audio latency](/docs/core/audio/latency/measure#measuringRoundTrip),\nby sending an encoded signal through the output and then looking for that matching signal on the input.\nThe time between the two is the combined input plus output latency.\nThis technique is used in [OboeTester](https://github.com/google/oboe/tree/main/apps/OboeTester/docs) and in CTS Verifier.\n\nA Loopback Dongle based on the circuit below is available from\n[PassMark Software](https://www.passmark.com/products/audio-loopback-plug/index.php).\nThis isn't a recommendation or an endorsement. Google does not have a business relationship with PassMark.\n\nCircuit\n-------\n\n\n**Figure 1.** circuit diagram\n\n\nTo ensure that the output signal will not overload the microphone input,\nwe cut it down by about 20dB.\nThe resistor loads tell the microphone polarity switch that\nthe audio loopback dongle is a US/CTIA pinout Tip Ring Ring Shield (TRRS) plug.\n\nAssembled\n---------\n\n\n**Figure 2.** Assembled"]]
