From 5dff50ada9773c8bd61099b21370cd7dfec33341 Mon Sep 17 00:00:00 2001 From: Marcus Tomlinson Date: Fri, 26 Oct 2018 20:10:11 +0100 Subject: [PATCH] Add loopback support to WASAPI --- RtAudio.cpp | 94 +++++++++++++++++++++++++++++++++-------------------- 1 file changed, 59 insertions(+), 35 deletions(-) diff --git a/RtAudio.cpp b/RtAudio.cpp index d23524d..34472d8 100644 --- a/RtAudio.cpp +++ b/RtAudio.cpp @@ -4727,7 +4727,7 @@ bool RtApiWasapi::probeDeviceOpen( unsigned int device, StreamMode mode, unsigne goto Exit; } - // determine whether index falls within capture or render devices + // if device index falls within capture devices if ( device >= renderDeviceCount ) { if ( mode != INPUT ) { errorType = RtAudioError::INVALID_USE; @@ -4747,26 +4747,52 @@ bool RtApiWasapi::probeDeviceOpen( unsigned int device, StreamMode mode, unsigne hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL, NULL, ( void** ) &captureAudioClient ); if ( FAILED( hr ) ) { - errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device audio client."; + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve capture device audio client."; goto Exit; } hr = captureAudioClient->GetMixFormat( &deviceFormat ); if ( FAILED( hr ) ) { - errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device mix format."; + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve capture device mix format."; goto Exit; } stream_.nDeviceChannels[mode] = deviceFormat->nChannels; captureAudioClient->GetStreamLatency( ( long long* ) &stream_.latency[mode] ); } - else { - if ( mode != OUTPUT ) { - errorType = RtAudioError::INVALID_USE; - errorText_ = "RtApiWasapi::probeDeviceOpen: Render device selected as input device."; + + // if device index falls within render devices and is configured for loopback + if ( device < renderDeviceCount && mode == INPUT ) + { + // retrieve captureAudioClient from devicePtr + IAudioClient*& captureAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->captureAudioClient; + + hr = renderDevices->Item( device, &devicePtr ); + if ( FAILED( hr ) ) { + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device handle."; goto Exit; } + hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL, + NULL, ( void** ) &captureAudioClient ); + if ( FAILED( hr ) ) { + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device audio client."; + goto Exit; + } + + hr = captureAudioClient->GetMixFormat( &deviceFormat ); + if ( FAILED( hr ) ) { + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device mix format."; + goto Exit; + } + + stream_.nDeviceChannels[mode] = deviceFormat->nChannels; + captureAudioClient->GetStreamLatency( ( long long* ) &stream_.latency[mode] ); + } + + // if device index falls within render devices and is configured for output + if ( device < renderDeviceCount && mode == OUTPUT ) + { // retrieve renderAudioClient from devicePtr IAudioClient*& renderAudioClient = ( ( WasapiHandle* ) stream_.apiHandle )->renderAudioClient; @@ -4779,13 +4805,13 @@ bool RtApiWasapi::probeDeviceOpen( unsigned int device, StreamMode mode, unsigne hr = devicePtr->Activate( __uuidof( IAudioClient ), CLSCTX_ALL, NULL, ( void** ) &renderAudioClient ); if ( FAILED( hr ) ) { - errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device audio client."; + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device audio client."; goto Exit; } hr = renderAudioClient->GetMixFormat( &deviceFormat ); if ( FAILED( hr ) ) { - errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve device mix format."; + errorText_ = "RtApiWasapi::probeDeviceOpen: Unable to retrieve render device mix format."; goto Exit; } @@ -4925,6 +4951,7 @@ void RtApiWasapi::wasapiThread() unsigned int bufferFrameCount = 0; unsigned int numFramesPadding = 0; unsigned int convBufferSize = 0; + bool loopbackEnabled = stream_.device[INPUT] == stream_.device[OUTPUT]; bool callbackPushed = true; bool callbackPulled = false; bool callbackStopped = false; @@ -4962,15 +4989,11 @@ void RtApiWasapi::wasapiThread() captureSrRatio = ( ( float ) captureFormat->nSamplesPerSec / stream_.sampleRate ); - // initialize capture stream according to desire buffer size - float desiredBufferSize = stream_.bufferSize * captureSrRatio; - REFERENCE_TIME desiredBufferPeriod = ( REFERENCE_TIME ) ( ( float ) desiredBufferSize * 10000000 / captureFormat->nSamplesPerSec ); - if ( !captureClient ) { hr = captureAudioClient->Initialize( AUDCLNT_SHAREMODE_SHARED, - AUDCLNT_STREAMFLAGS_EVENTCALLBACK, - desiredBufferPeriod, - desiredBufferPeriod, + loopbackEnabled ? AUDCLNT_STREAMFLAGS_LOOPBACK : AUDCLNT_STREAMFLAGS_EVENTCALLBACK, + 0, + 0, captureFormat, NULL ); if ( FAILED( hr ) ) { @@ -4985,22 +5008,27 @@ void RtApiWasapi::wasapiThread() goto Exit; } - // configure captureEvent to trigger on every available capture buffer - captureEvent = CreateEvent( NULL, FALSE, FALSE, NULL ); - if ( !captureEvent ) { - errorType = RtAudioError::SYSTEM_ERROR; - errorText_ = "RtApiWasapi::wasapiThread: Unable to create capture event."; - goto Exit; - } + // don't configure captureEvent if in loopback mode + if ( !loopbackEnabled ) + { + // configure captureEvent to trigger on every available capture buffer + captureEvent = CreateEvent( NULL, FALSE, FALSE, NULL ); + if ( !captureEvent ) { + errorType = RtAudioError::SYSTEM_ERROR; + errorText_ = "RtApiWasapi::wasapiThread: Unable to create capture event."; + goto Exit; + } - hr = captureAudioClient->SetEventHandle( captureEvent ); - if ( FAILED( hr ) ) { - errorText_ = "RtApiWasapi::wasapiThread: Unable to set capture event handle."; - goto Exit; + hr = captureAudioClient->SetEventHandle( captureEvent ); + if ( FAILED( hr ) ) { + errorText_ = "RtApiWasapi::wasapiThread: Unable to set capture event handle."; + goto Exit; + } + + ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent = captureEvent; } ( ( WasapiHandle* ) stream_.apiHandle )->captureClient = captureClient; - ( ( WasapiHandle* ) stream_.apiHandle )->captureEvent = captureEvent; } unsigned int inBufferSize = 0; @@ -5047,15 +5075,11 @@ void RtApiWasapi::wasapiThread() renderSrRatio = ( ( float ) renderFormat->nSamplesPerSec / stream_.sampleRate ); - // initialize render stream according to desire buffer size - float desiredBufferSize = stream_.bufferSize * renderSrRatio; - REFERENCE_TIME desiredBufferPeriod = ( REFERENCE_TIME ) ( ( float ) desiredBufferSize * 10000000 / renderFormat->nSamplesPerSec ); - if ( !renderClient ) { hr = renderAudioClient->Initialize( AUDCLNT_SHAREMODE_SHARED, AUDCLNT_STREAMFLAGS_EVENTCALLBACK, - desiredBufferPeriod, - desiredBufferPeriod, + 0, + 0, renderFormat, NULL ); if ( FAILED( hr ) ) { @@ -5308,7 +5332,7 @@ void RtApiWasapi::wasapiThread() if ( captureAudioClient ) { // if the callback input buffer was not pulled from captureBuffer, wait for next capture event if ( !callbackPulled ) { - WaitForSingleObject( captureEvent, INFINITE ); + WaitForSingleObject( loopbackEnabled ? renderEvent : captureEvent, INFINITE ); } // Get capture buffer from stream -- 2.30.2