private void initPlayer()
{
Encoding encoding = Encoding.Pcm16bit;
bufferSize = AudioTrack.GetMinBufferSize(sampleRate, ChannelOut.Mono, encoding);
Logging.info("Min. buffer size " + bufferSize);
int new_buffer_size = CodecTools.getPcmFrameByteSize(sampleRate, bitRate, channels) * 100;
if (bufferSize < new_buffer_size)
{
bufferSize = (int)(Math.Ceiling((decimal)new_buffer_size / bufferSize) * bufferSize);
}
Logging.info("Final buffer size " + bufferSize);
// Prepare player
AudioAttributes aa = new AudioAttributes.Builder()
.SetContentType(AudioContentType.Speech)
.SetFlags(AudioFlags.LowLatency)
.SetUsage(AudioUsageKind.VoiceCommunication)
.Build();
AudioFormat af = new AudioFormat.Builder()
.SetSampleRate(sampleRate)
.SetChannelMask(ChannelOut.Mono)
.SetEncoding(encoding)
.Build();
audioPlayer = new AudioTrack(aa, af, bufferSize, AudioTrackMode.Stream, 0);
MainActivity.Instance.VolumeControlStream = Stream.VoiceCall;
audioPlayer.Play();
}
private void initRecorder()
{
audioRecorder = new AVAudioEngine();
NSError error = new NSError();
if (!AVAudioSession.SharedInstance().SetPreferredSampleRate(sampleRate, out error))
{
throw new Exception("Error setting preffered sample rate for recorder: " + error);
}
AVAudioSession.SharedInstance().SetCategory(AVAudioSessionCategory.PlayAndRecord, AVAudioSessionCategoryOptions.InterruptSpokenAudioAndMixWithOthers);
AVAudioSession.SharedInstance().SetActive(true);
AVAudioFormat recording_format = new AVAudioFormat(AVAudioCommonFormat.PCMInt16, sampleRate, (uint)channels, false);
uint buffer_size = (uint)CodecTools.getPcmFrameByteSize(sampleRate, bitRate, channels) * 1000;
audioRecorder.InputNode.InstallTapOnBus(0, buffer_size, recording_format, onDataAvailable);
audioRecorder.Prepare();
if (!audioRecorder.StartAndReturnError(out error))
{
throw new Exception("Error starting recording audio engine: " + error);
}
}