private async Task Activate()
{
var icbh = new ActivateAudioInterfaceCompletionHandler(
ac2 =>
{
if (this.audioClientProperties != null)
{
IntPtr p = Marshal.AllocHGlobal(Marshal.SizeOf(this.audioClientProperties.Value));
Marshal.StructureToPtr(this.audioClientProperties.Value, p, false);
ac2.SetClientProperties(p);
Marshal.FreeHGlobal(p);
// TODO: consider whether we can marshal this without the need for AllocHGlobal
}
/*var wfx = new WaveFormat(44100, 16, 2);
* int hr = ac2.Initialize(AudioClientShareMode.Shared,
* AudioClientStreamFlags.EventCallback | AudioClientStreamFlags.NoPersist,
* 10000000, 0, wfx, IntPtr.Zero);*/
});
var IID_IAudioClient2 = new Guid("726778CD-F60A-4eda-82DE-E47610CD78AA");
IActivateAudioInterfaceAsyncOperation activationOperation;
NativeMethodsRT.ActivateAudioInterfaceAsync(device, IID_IAudioClient2, IntPtr.Zero, icbh, out activationOperation);
var audioClient2 = await icbh;
audioClient = new AudioClient((IAudioClient)audioClient2);
}
/// <summary>
/// Initialize for playing the specified wave stream
/// </summary>
private IWaveProvider Init()
{
var waveProvider = waveProviderFunc();
long latencyRefTimes = latencyMilliseconds * 10000;
outputFormat = waveProvider.WaveFormat;
// first attempt uses the WaveFormat from the WaveStream
WaveFormatExtensible closestSampleRateFormat;
if (!audioClient.IsFormatSupported(shareMode, outputFormat, out closestSampleRateFormat))
{
// Use closesSampleRateFormat (in sharedMode, it equals usualy to the audioClient.MixFormat)
// See documentation : http://msdn.microsoft.com/en-us/library/ms678737(VS.85).aspx
// They say : "In shared mode, the audio engine always supports the mix format"
// The MixFormat is more likely to be a WaveFormatExtensible.
if (closestSampleRateFormat == null)
{
WaveFormat correctSampleRateFormat = audioClient.MixFormat;
/*WaveFormat.CreateIeeeFloatWaveFormat(
* audioClient.MixFormat.SampleRate,
* audioClient.MixFormat.Channels);*/
if (!audioClient.IsFormatSupported(shareMode, correctSampleRateFormat))
{
// Iterate from Worst to Best Format
WaveFormatExtensible[] bestToWorstFormats =
{
new WaveFormatExtensible(
outputFormat.SampleRate, 32,
outputFormat.Channels),
new WaveFormatExtensible(
outputFormat.SampleRate, 24,
outputFormat.Channels),
new WaveFormatExtensible(
outputFormat.SampleRate, 16,
outputFormat.Channels),
};
// Check from best Format to worst format ( Float32, Int24, Int16 )
for (int i = 0; i < bestToWorstFormats.Length; i++)
{
correctSampleRateFormat = bestToWorstFormats[i];
if (audioClient.IsFormatSupported(shareMode, correctSampleRateFormat))
{
break;
}
correctSampleRateFormat = null;
}
// If still null, then test on the PCM16, 2 channels
if (correctSampleRateFormat == null)
{
// Last Last Last Chance (Thanks WASAPI)
correctSampleRateFormat = new WaveFormatExtensible(outputFormat.SampleRate, 16, 2);
if (!audioClient.IsFormatSupported(shareMode, correctSampleRateFormat))
{
throw new NotSupportedException("Can't find a supported format to use");
}
}
}
outputFormat = correctSampleRateFormat;
}
else
{
outputFormat = closestSampleRateFormat;
}
// just check that we can make it.
//using (new MediaFoundationResampler(waveProvider, outputFormat))
{
}
this.resamplerNeeded = true;
}
else
{
resamplerNeeded = false;
}
// Init Shared or Exclusive
if (shareMode == AudioClientShareMode.Shared)
{
// With EventCallBack and Shared,
audioClient.Initialize(shareMode, AudioClientStreamFlags.EventCallback, latencyRefTimes, 0,
outputFormat, Guid.Empty);
// Get back the effective latency from AudioClient. On Windows 10 it can be 0
if (audioClient.StreamLatency > 0)
{
latencyMilliseconds = (int)(audioClient.StreamLatency / 10000);
}
}
else
{
// With EventCallBack and Exclusive, both latencies must equals
audioClient.Initialize(shareMode, AudioClientStreamFlags.EventCallback, latencyRefTimes, latencyRefTimes,
outputFormat, Guid.Empty);
}
// Create the Wait Event Handle
frameEventWaitHandle = NativeMethodsRT.CreateEventExW(IntPtr.Zero, IntPtr.Zero, 0, EventAccess.EVENT_ALL_ACCESS);
audioClient.SetEventHandle(frameEventWaitHandle);
// Get the RenderClient
renderClient = audioClient.AudioRenderClient;
return(waveProvider);
}
private async void PlayThread()
{
await Activate();
var playbackProvider = Init();
bool isClientRunning = false;
try
{
if (this.resamplerNeeded)
{
var resampler = new WdlResamplingSampleProvider(playbackProvider.ToSampleProvider(), outputFormat.SampleRate);
playbackProvider = new SampleToWaveProvider(resampler);
}
// fill a whole buffer
bufferFrameCount = audioClient.BufferSize;
bytesPerFrame = outputFormat.Channels * outputFormat.BitsPerSample / 8;
readBuffer = new byte[bufferFrameCount * bytesPerFrame];
FillBuffer(playbackProvider, bufferFrameCount);
int timeout = 3 * latencyMilliseconds;
while (playbackState != WasapiOutState.Disposed)
{
if (playbackState != WasapiOutState.Playing)
{
playThreadEvent.WaitOne(500);
}
// If still playing and notification is ok
if (playbackState == WasapiOutState.Playing)
{
if (!isClientRunning)
{
audioClient.Start();
isClientRunning = true;
}
// If using Event Sync, Wait for notification from AudioClient or Sleep half latency
var r = NativeMethodsRT.WaitForSingleObjectEx(frameEventWaitHandle, timeout, true);
if (r != 0)
{
throw new InvalidOperationException("Timed out waiting for event");
}
// See how much buffer space is available.
int numFramesPadding = 0;
// In exclusive mode, always ask the max = bufferFrameCount = audioClient.BufferSize
numFramesPadding = (shareMode == AudioClientShareMode.Shared) ? audioClient.CurrentPadding : 0;
int numFramesAvailable = bufferFrameCount - numFramesPadding;
if (numFramesAvailable > 0)
{
FillBuffer(playbackProvider, numFramesAvailable);
}
}
if (playbackState == WasapiOutState.Stopping)
{
// play the buffer out
while (audioClient.CurrentPadding > 0)
{
await Task.Delay(latencyMilliseconds / 2);
}
audioClient.Stop();
isClientRunning = false;
audioClient.Reset();
playbackState = WasapiOutState.Stopped;
RaisePlaybackStopped(null);
}
if (playbackState == WasapiOutState.Disposing)
{
audioClient.Stop();
isClientRunning = false;
audioClient.Reset();
playbackState = WasapiOutState.Disposed;
var disposablePlaybackProvider = playbackProvider as IDisposable;
if (disposablePlaybackProvider != null)
{
disposablePlaybackProvider.Dispose(); // do everything on this thread, even dispose in case it is Media Foundation
}
RaisePlaybackStopped(null);
}
}
}
catch (Exception e)
{
RaisePlaybackStopped(e);
}
finally
{
audioClient.Dispose();
audioClient = null;
renderClient = null;
NativeMethodsRT.CloseHandle(frameEventWaitHandle);
}
}