private long GetLength(IMFSourceReader reader)
{
var variantPtr = Marshal.AllocHGlobal(MarshalHelpers.SizeOf <PropVariant>());
try
{
// http://msdn.microsoft.com/en-gb/library/windows/desktop/dd389281%28v=vs.85%29.aspx#getting_file_duration
int hResult = reader.GetPresentationAttribute(MediaFoundationInterop.MF_SOURCE_READER_MEDIASOURCE,
MediaFoundationAttributes.MF_PD_DURATION, variantPtr);
if (hResult == MediaFoundationErrors.MF_E_ATTRIBUTENOTFOUND)
{
// this doesn't support telling us its duration (might be streaming)
return(0);
}
if (hResult != 0)
{
Marshal.ThrowExceptionForHR(hResult);
}
var variant = MarshalHelpers.PtrToStructure <PropVariant>(variantPtr);
var lengthInBytes = (((long)variant.Value) * waveFormat.AverageBytesPerSecond) / 10000000L;
return(lengthInBytes);
}
finally
{
PropVariant.Clear(variantPtr);
Marshal.FreeHGlobal(variantPtr);
}
}
private static long GetDuration(IMFSourceReader reader)
{
var variantPtr = Marshal.AllocHGlobal(MarshalHelpers.SizeOf <PropVariant>());
try
{
int hResult = reader.GetPresentationAttribute(MediaFoundationInterop.MF_SOURCE_READER_MEDIASOURCE,
MediaFoundationAttributes.MF_PD_DURATION, variantPtr);
if (hResult == MediaFoundationErrors.MF_E_ATTRIBUTENOTFOUND)
{
return(0);
}
if (hResult != 0)
{
Marshal.ThrowExceptionForHR(hResult);
}
var variant = MarshalHelpers.PtrToStructure <PropVariant> (variantPtr);
return((long)variant.Value);
}
finally
{
PropVariant.Clear(variantPtr);
Marshal.FreeHGlobal(variantPtr);
}
}
private long GetLength(IMFSourceReader reader)
{
IntPtr intPtr = Marshal.AllocHGlobal(MarshalHelpers.SizeOf <PropVariant>());
long result;
try
{
int presentationAttribute = reader.GetPresentationAttribute(-1, MediaFoundationAttributes.MF_PD_DURATION, intPtr);
if (presentationAttribute == -1072875802)
{
result = 0L;
}
else
{
if (presentationAttribute != 0)
{
Marshal.ThrowExceptionForHR(presentationAttribute);
}
result = (long)MarshalHelpers.PtrToStructure <PropVariant>(intPtr).Value *(long)this.waveFormat.AverageBytesPerSecond / 10000000L;
}
}
finally
{
PropVariant.Clear(intPtr);
Marshal.FreeHGlobal(intPtr);
}
return(result);
}
/// <summary>
/// Gets an attribute from the underlying media source.
/// </summary>
/// <param name="sourceReader">A valid IMFSourceReader instance.</param></param>
/// <param name="streamIndex">The streamIndex to query.</param>
/// <param name="mediaTypeIndex">The zero-based index of the media type to retrieve.</param>
/// <param name="mediaType">Receives an instance of the IMFMediaType interface.</param>
/// <returns>If this function succeeds, it returns the S_OK member. Otherwise, it returns another HResult's member that describe the error.</returns>
public static HResult GetPresentationAttribute(this IMFSourceReader sourceReader, SourceReaderFirstStreamOrMediaSource streamIndex, Guid guidAttribute, PropVariant attribute)
{
if (sourceReader == null)
{
throw new ArgumentNullException("sourceReader");
}
return(sourceReader.GetPresentationAttribute((int)streamIndex, guidAttribute, attribute));
}
private long GetLength(IMFSourceReader reader)
{
PropVariant propVariant;
int presentationAttribute = reader.GetPresentationAttribute(-1, MediaFoundationAttributes.MF_PD_DURATION, out propVariant);
if (presentationAttribute == -1072875802)
{
return(0L);
}
if (presentationAttribute != 0)
{
Marshal.ThrowExceptionForHR(presentationAttribute);
}
long result = (long)propVariant.Value * (long)this.waveFormat.AverageBytesPerSecond / 10000000L;
propVariant.Clear();
return(result);
}
private long GetLength(IMFSourceReader reader)
{
PropVariant variant;
// http://msdn.microsoft.com/en-gb/library/windows/desktop/dd389281%28v=vs.85%29.aspx#getting_file_duration
int hResult = reader.GetPresentationAttribute(MediaFoundationInterop.MF_SOURCE_READER_MEDIASOURCE,
MediaFoundationAttributes.MF_PD_DURATION, out variant);
if (hResult == MediaFoundationErrors.MF_E_ATTRIBUTENOTFOUND)
{
// this doesn't support telling us its duration (might be streaming)
return 0;
}
if (hResult != 0)
{
Marshal.ThrowExceptionForHR(hResult);
}
var lengthInBytes = (((long)variant.Value) * waveFormat.AverageBytesPerSecond) / 10000000L;
variant.Clear();
return lengthInBytes;
}
