/// <summary>
/// Use Source Reader to allocate a sample
/// </summary>
/// <param name="sourceReader">The Source Reader</param>
/// <param name="dwStreamIndex">The stream to pull data from</param>
/// <param name="dwControlFlags">A bitwise OR of zero or more flags from the MF_SOURCE_READER_CONTROL_FLAG enumeration</param>
/// <param name="pdwActualStreamIndex">Receives the zero-based index of the stream</param>
/// <param name="pdwStreamFlags">Receives a bitwise OR of zero or more flags from the MF_SOURCE_READER_FLAG enumeration</param>
/// <param name="pllTimestamp">Receives the time stamp of the sample, or the time of the stream event indicated in pdwStreamFlags. The time is given in 100-nanosecond units</param>
public void ReadSampleFrom(
IMFSourceReader sourceReader,
uint dwStreamIndex,
uint dwControlFlags,
out uint pdwActualStreamIndex,
out uint pdwStreamFlags,
out ulong pllTimestamp)
{
// Once a sample is read avoid reading more samples
if (this.read)
{
throw new InvalidOperationException("Already holding a sample");
}
sourceReader.ReadSample(dwStreamIndex, dwControlFlags, out pdwActualStreamIndex, out pdwStreamFlags, out pllTimestamp, out this.sample);
if (this.sample != null)
{
// Get the size of the media sample in bytes
IMFMediaBuffer buffer = null;
this.sample.GetBufferByIndex(0, out buffer);
buffer.GetCurrentLength(out this.bufferSize);
// Add the memory pressure of unmanaged memory to improve the garbage collector performance
GC.AddMemoryPressure(this.bufferSize);
}
this.read = true;
}
private void invokeDecodeComplete(IMFMediaBuffer buffer, int bufferLen)
{
if (buffer == null)
{
return;
}
int len = 0;
buffer.GetCurrentLength(out len);
if (bufferLen != len)
{
//todo: throw invalid data exception.
return;
}
invokeDecodeCompleteEvent(buffer);
}