private void NegotiateStream(uint streamIndex, Guid majorType, Guid[] possibleSubtypes)
{
IMFMediaType outputMediaType = null;
Exception lastException = null;
bool foundValidType = false;
foreach (Guid subType in possibleSubtypes)
{
try
{
// Create a partial media type
MFHelper.MFCreateMediaType(out outputMediaType);
outputMediaType.SetGUID(new Guid(Consts.MF_MT_MAJOR_TYPE), majorType);
outputMediaType.SetGUID(new Guid(Consts.MF_MT_SUBTYPE), subType);
// Set it as the current media type in source reader
this.sourceReader.SetCurrentMediaType(streamIndex, IntPtr.Zero, outputMediaType);
// Get the full media type from Source Reader
this.sourceReader.GetCurrentMediaType(streamIndex, out outputMediaType);
// Set it as the input media type in Sink Writer
this.sinkWriter.SetInputMediaType(this.streamsInfo[streamIndex].OutputStreamIndex, outputMediaType, null);
// If no exceptions were thrown a suitable media type was found
foundValidType = true;
// Break from the loop so no more media types are tried
break;
}
catch (Exception ex)
{
// Something went wrong, the loop will continue and the next type will be tried
lastException = ex;
}
}
// If FormatFound is false no suitable type was found and the operation can't continue
if (foundValidType == false)
{
if (lastException != null)
{
throw new Exception(lastException.Message, lastException);
}
else
{
throw new Exception("Unknown error occurred");
}
}
}
private IMFMediaType CreateTargetVideoMediaType()
{
IMFMediaType mediaType = null;
MFHelper.MFCreateMediaType(out mediaType);
mediaType.SetGUID(new Guid(Consts.MF_MT_MAJOR_TYPE), new Guid(Consts.MFMediaType_Video));
mediaType.SetGUID(new Guid(Consts.MF_MT_SUBTYPE), this.videoOutput.Subtype);
mediaType.SetUINT64(new Guid(Consts.MF_MT_FRAME_SIZE), this.videoOutput.FrameSize.Packed);
mediaType.SetUINT64(new Guid(Consts.MF_MT_FRAME_RATE), this.videoOutput.FrameRate.Packed);
mediaType.SetUINT64(new Guid(Consts.MF_MT_PIXEL_ASPECT_RATIO), this.videoOutput.PixelAspectRatio.Packed);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AVG_BITRATE), this.videoOutput.AvgBitRate);
mediaType.SetUINT32(new Guid(Consts.MF_MT_INTERLACE_MODE), this.videoOutput.InterlaceMode);
return(mediaType);
}
private IMFMediaType CreateTargetAudioMediaType()
{
IMFMediaType mediaType = null;
if (audioOutput.Subtype.Equals(new Guid(Consts.MFAudioFormat_AAC)))
{
// Create the AAC media type
MFHelper.MFCreateMediaType(out mediaType);
mediaType.SetGUID(new Guid(Consts.MF_MT_MAJOR_TYPE), new Guid(Consts.MFMediaType_Audio));
mediaType.SetGUID(new Guid(Consts.MF_MT_SUBTYPE), this.audioOutput.Subtype);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AUDIO_AVG_BYTES_PER_SECOND), this.audioOutput.AvgBytePerSecond);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AUDIO_NUM_CHANNELS), this.audioOutput.NumOfChannels);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AUDIO_SAMPLES_PER_SECOND), this.audioOutput.SamplesPerSecond);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AUDIO_BLOCK_ALIGNMENT), this.audioOutput.BlockAlignment);
mediaType.SetUINT32(new Guid(Consts.MF_MT_AUDIO_BITS_PER_SAMPLE), this.audioOutput.BitsPerSample);
}
else
{
// Create the WMA media type
uint codecConfig = 0;
uint elementsNumber = 0;
uint selectedType = 0;
int avgBitrateDiff = int.MaxValue;
uint avgBytePerSecond = uint.MaxValue;
object supportedAttributes = null;
// Get the available audio ouput types for the required sub type
IMFCollection availableTypes = null;
MFHelper.MFTranscodeGetAudioOutputAvailableTypes(audioOutput.Subtype, (uint)Enums.MFT_ENUM_FLAG.MFT_ENUM_FLAG_ALL, codecConfig, out availableTypes);
// Get the number of types
availableTypes.GetElementCount(out elementsNumber);
for (uint elementIndex = 0; elementIndex < elementsNumber; elementIndex++)
{
// Get the next element
availableTypes.GetElement(elementIndex, out supportedAttributes);
mediaType = (IMFMediaType)supportedAttributes;
// Get the byte per second
mediaType.GetUINT32(new Guid(Consts.MF_MT_AUDIO_AVG_BYTES_PER_SECOND), out avgBytePerSecond);
// If this is better than the last one found remember the index
if (Math.Abs((int)avgBytePerSecond - (int)audioOutput.AvgBytePerSecond) < avgBitrateDiff)
{
selectedType = elementIndex;
avgBitrateDiff = Math.Abs((int)avgBytePerSecond - (int)audioOutput.AvgBytePerSecond);
}
mediaType = null;
}
// Get the best audio type found
availableTypes.GetElement(selectedType, out supportedAttributes);
mediaType = (IMFMediaType)supportedAttributes;
}
return(mediaType);
}