Sample app for Android 10's AudioPlaybackCapture API, which allows applications to capture the audio of other applications.
This app serves as a showcase for how to request the proper permissions and architect an application by using a foreground service that wraps the audio sample data capturing. You can also use it to ensure your application behaves properly when targetting API level 29 and above.
Check the official API release blog post for more information on how to allow/disallow apps from recording your apps' media output.
Tapping the "Capture audio" button on the UI will present two permission requests:
Once both are granted, a foreground service (with an attached status bar notification) will be started, spawning a thread that performs the audio sample capturing. For the sake of the example, these samples have hardcoded characteristics in the configuration object:
- Sample rate of 8000 Hz
- Mono channel
- No encoding: PCM 16-bit (byte-order: little endian)
Until the "Stop capture" button is tapped, the samples are written to a file in disk under the /data directory of the showcase application. The path to the written file will be outputted to LogCat, like so
D/AudioCaptureService: Audio capture finished for /storage/emulated/0/Android/data/com.zynger.audiocapturesample/files/AudioCaptures/Capture-01-10-2019-05-21-22.pcm. File size is 395264 bytes.
You can then pull the file from the device and play the media back. Make sure you use a player that is capable of rendering raw PCM data (for example, on Audacity, you can File > Import > Raw Data).
