1. Public void startAudioCapture()
2.  
3. {
4.  
5.     val config = AudioPlaybackCaptureConfiguration.Builder(mediaProjection!!)
6.  
7.             .addMatchingUsage(AudioAttributes.USAGE_MEDIA) // TODO provide UI options for inclusion/exclusion
8.  
9.             .build()
10.  
11.  
12.         /**
13.  
14.          * Using hardcoded values for the audio format, Mono PCM samples with a sample rate of 8000Hz
15.  
16.          * These can be changed according to your application's needs
17.  
18.          */
19.  
20.         val audioFormat = AudioFormat.Builder()
21.  
22.             .setEncoding(AudioFormat.ENCODING_PCM_FLOAT)
23.  
24.             .setSampleRate(8000)
25.  
26.             .setChannelMask(AudioFormat.CHANNEL_IN_MONO)
27.  
28.             .build()
29.  
30.  
31.         audioRecord = AudioRecord.Builder()
32.  
33.             .setAudioFormat(audioFormat)
34.  
35.             // For optimal performance, the buffer size
36.  
37.             // can be optionally specified to store audio samples.
38.  
39.             // If the value is not specified,
40.  
41.             // uses a single frame and lets the
42.  
43.             // native code figure out the minimum buffer size.
44.  
45.             .setBufferSizeInBytes(BUFFER_SIZE_IN_BYTES)
46.  
47.             .setAudioPlaybackCaptureConfig(config)
48.  
49.             .build()
50.  
51.  
52.         audioRecord!!.startRecording()
53.  
54.         audioCaptureThread = thread(start = true) {
55.  
56.             val outputFile = createAudioFile()
57.  
58.             Log.d(LOG_TAG, "Created file for capture target: ${outputFile.absolutePath}")
59.  
60.             writeAudioToFile(outputFile)
61.  
62.         }
63.  
64. }
65.  
66.