/// <summary>
/// Starts buffering the audio data from the remote track in an <see cref="AudioTrackReadBuffer"/>.
/// </summary>
/// <remarks>
/// WebRTC audio tracks produce an audio frame every 10 ms.
/// If you want the audio frames to be buffered (and optionally resampled) automatically,
/// and you want the application to control when new audio data is read, create an
/// <see cref="AudioTrackReadBuffer"/> using <see cref="CreateReadBuffer"/>.
/// If you want to process the audio frames as soon as they are received, without conversions,
/// subscribe to <see cref="AudioFrameReady"/> instead.
/// </remarks>
public AudioTrackReadBuffer CreateReadBuffer()
{
uint res = RemoteAudioTrackInterop.RemoteAudioTrack_CreateReadBuffer(_nativeHandle,
out RemoteAudioTrackInterop.ReadBufferHandle readBufferHandle);
Utils.ThrowOnErrorCode(res);
return(new AudioTrackReadBuffer(readBufferHandle));
}
/// <summary>
/// Fill <paramref name="samplesOut"/> with samples from the internal buffer.
/// </summary>
/// <remarks>
/// This method reads the internal buffer starting from the oldest data.
/// If the internal buffer is exhausted (underrun), <paramref name="samplesOut"/>
/// is padded according to the value of <paramref name="padBehavior"/>.
///
/// This method should be called regularly to consume the audio data as it is
/// received. Note that the internal buffer can overrun (and some frames can be
/// dropped) if this is not called frequently enough.
/// </remarks>
/// <param name="sampleRate">
/// Desired sample rate. Data in the buffer is resampled if this is different from
/// the native track rate.
/// </param>
/// <param name="numChannels">
/// Desired number of channels. Should be 1 or 2. Data in the buffer is split/averaged
/// if this is different from the native track channels number.
/// </param>
/// <param name="samplesOut">
/// Will be filled with the samples read from the internal buffer. The function will
/// try to fill the entire length of the array.
/// </param>
/// <param name="numSamplesRead">
/// Set to the effective number of samples read.
/// This will be generally equal to the length of <paramref name="samplesOut"/>, but can be less in
/// case of underrun.
/// </param>
/// <param name="hasOverrun">
/// Set to <c>true</c> if frames have been dropped from the internal
/// buffer between the previous call to <c>Read</c> and this.
/// </param>
/// <param name="padBehavior">Controls how <paramref name="samplesOut"/> is padded in case of underrun.</param>
public void Read(int sampleRate, int numChannels,
float[] samplesOut, out int numSamplesRead, out bool hasOverrun,
PadBehavior padBehavior = PadBehavior.PadWithZero)
{
RemoteAudioTrackInterop.AudioTrackReadBuffer_Read(_nativeHandle,
sampleRate, numChannels, padBehavior, samplesOut, samplesOut.Length, out numSamplesRead, out mrsBool has_overrun_res);
hasOverrun = (bool)has_overrun_res;
}
private void UnregisterInteropCallbacks()
{
if (_selfHandle != IntPtr.Zero)
{
RemoteAudioTrackInterop.RemoteAudioTrack_RegisterFrameCallback(_nativeHandle, null, IntPtr.Zero);
Utils.ReleaseWrapperRef(_selfHandle);
_selfHandle = IntPtr.Zero;
_interopCallbackArgs = null;
}
}
private void RegisterInteropCallbacks()
{
_interopCallbackArgs = new RemoteAudioTrackInterop.InteropCallbackArgs()
{
Track = this,
FrameCallback = RemoteAudioTrackInterop.FrameCallback,
};
_selfHandle = Utils.MakeWrapperRef(this);
RemoteAudioTrackInterop.RemoteAudioTrack_RegisterFrameCallback(
_nativeHandle, _interopCallbackArgs.FrameCallback, _selfHandle);
}
/// <summary>
/// Returns whether the track is output directly to the system audio device.
/// </summary>
public bool IsOutputToDevice()
{
return((bool)RemoteAudioTrackInterop.RemoteAudioTrack_IsOutputToDevice(_nativeHandle));
}
/// <summary>
/// Output the audio track to the WebRTC audio device.
/// </summary>
/// <remarks>
/// The default behavior is for every remote audio frame to be passed to
/// remote audio frame callbacks, as well as output automatically to the
/// audio device used by WebRTC. If |false| is passed to this function, remote
/// audio frames will still be received and passed to callbacks, but won't be
/// output to the audio device.
///
/// NOTE: Changing the default behavior is not supported on UWP.
/// </remarks>
public void OutputToDevice(bool output)
{
RemoteAudioTrackInterop.RemoteAudioTrack_OutputToDevice(_nativeHandle, (mrsBool)output);
}