Support mono audio for PcmFormat::Int16Planes.

OtherCrashOverride · Oct 8, 2016 · 71af462 · 71af462
1 parent f090597
commit 71af462
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Showing 2 changed files with 76 additions and 23 deletions.
diff --git a/src/Media/AlsaAudioSink.cpp b/src/Media/AlsaAudioSink.cpp
@@ -89,6 +89,15 @@ void AlsaAudioSinkElement::ProcessBuffer(PcmDataBufferSPTR pcmBuffer)
 
 	if (pcmData->Format == PcmFormat::Int16)
 	{
+		if (alsa_channels != 2)
+		{
+			throw InvalidOperationException();
+		}
+
+		if (pcmData->Channels < 2)
+			throw NotSupportedException();
+
+
 		int stride = pcmData->Channels * sizeof(short);
 		unsigned char* source = (unsigned char*)pcmData->Channel[0];
 
@@ -112,11 +121,32 @@ void AlsaAudioSinkElement::ProcessBuffer(PcmDataBufferSPTR pcmBuffer)
 	}
 	else if (pcmData->Format == PcmFormat::Int16Planes)
 	{
+		if (alsa_channels != 2)
+		{
+			throw InvalidOperationException();
+		}
+
+
 		short* channels[alsa_channels] = { 0 };
 
-		channels[0] = (short*)pcmData->Channel[0];
-		channels[1] = (short*)pcmData->Channel[1];
+		int channelCount = pcmData->Channels;
 
+		switch (channelCount)
+		{
+			case 0:
+				throw InvalidOperationException("Unexpected zero channel count.");
+
+			case 1:
+				// Output the mono channel over both stereo channels
+				channels[0] = (short*)pcmData->Channel[0];
+				channels[1] = (short*)pcmData->Channel[0];
+				break;
+
+			default:
+				channels[0] = (short*)pcmData->Channel[0];
+				channels[1] = (short*)pcmData->Channel[1];
+				break;
+		}
 
 		int index = 0;
 		for (int i = 0; i < pcmData->Samples; ++i)
@@ -135,6 +165,9 @@ void AlsaAudioSinkElement::ProcessBuffer(PcmDataBufferSPTR pcmBuffer)
 			throw InvalidOperationException();
 		}
 
+		if (pcmData->Channels < 2)
+			throw NotSupportedException();
+
 
 		float* channels[alsa_channels] = { 0 };
 
@@ -184,9 +217,15 @@ void AlsaAudioSinkElement::ProcessBuffer(PcmDataBufferSPTR pcmBuffer)
 	}
 	else if (pcmData->Format == PcmFormat::Int32)
 	{
+		if (alsa_channels != 2)
+		{
+			throw InvalidOperationException();
+		}
+
 		if (pcmData->Channels < 2)
 			throw NotSupportedException();
 
+
 		// Signed 32 bit, interleaved
 		int srcIndex = 0;
 		int dstIndex = 0;

diff --git a/src/Media/AudioCodec.cpp b/src/Media/AudioCodec.cpp
@@ -218,34 +218,48 @@ void AudioCodecElement::ProcessBuffer(AVPacketBufferSPTR buffer, AVFrameBufferSP
 			}
 			else
 			{
-				int leftChannelIndex = av_get_channel_layout_channel_index(
-					decoded_frame->channel_layout,
-					AV_CH_FRONT_LEFT);
-
-				int rightChannelIndex = av_get_channel_layout_channel_index(
-					decoded_frame->channel_layout,
-					AV_CH_FRONT_RIGHT);
-
-				int centerChannelIndex = av_get_channel_layout_channel_index(
-					decoded_frame->channel_layout,
-					AV_CH_FRONT_CENTER);
-
-
 				// left, right, center
 				const int DOWNMIX_MAX_CHANNELS = 3;
 
 				void* channels[DOWNMIX_MAX_CHANNELS] = { 0 };
-				channels[0] = (void*)decoded_frame->data[leftChannelIndex];
-				channels[1] = (void*)decoded_frame->data[rightChannelIndex];
 
-				if (decoded_frame->channels > 2)
+				if (decoded_frame->channels == 1)
+				{
+					// Mono
+					int monoChannelIndex = av_get_channel_layout_channel_index(
+						decoded_frame->channel_layout,
+						AV_CH_FRONT_CENTER);
+
+
+					channels[0] = (void*)decoded_frame->data[monoChannelIndex];
+				}
+				else
 				{
-					channels[2] = (void*)decoded_frame->data[centerChannelIndex];
+					int leftChannelIndex = av_get_channel_layout_channel_index(
+						decoded_frame->channel_layout,
+						AV_CH_FRONT_LEFT);
+
+					int rightChannelIndex = av_get_channel_layout_channel_index(
+						decoded_frame->channel_layout,
+						AV_CH_FRONT_RIGHT);
+
+					int centerChannelIndex = av_get_channel_layout_channel_index(
+						decoded_frame->channel_layout,
+						AV_CH_FRONT_CENTER);
+
+
+					channels[0] = (void*)decoded_frame->data[leftChannelIndex];
+					channels[1] = (void*)decoded_frame->data[rightChannelIndex];
+
+					if (decoded_frame->channels > 2)
+					{
+						channels[2] = (void*)decoded_frame->data[centerChannelIndex];
+					}
+					//else
+					//{
+					//	channels[2] = nullptr;
+					//}
 				}
-				//else
-				//{
-				//	channels[2] = nullptr;
-				//}
 
 				int channelCount = std::min(DOWNMIX_MAX_CHANNELS, decoded_frame->channels);
 				for (int i = 0; i < channelCount; ++i)