private void InitAudioGrabber(IBaseFilter sourceF)
{
audioGrabberFilter = new SampleGrabber() as IBaseFilter;
if (audioGrabberFilter == null)
{
throw new COMException("Cannot create SampleGrabber");
}
int hr = graph.AddFilter(audioGrabberFilter, "Audio Sample Grabber");
DsError.ThrowExceptionForHR(hr);
audioGrabber = audioGrabberFilter as ISampleGrabber;
if (audioGrabber == null)
{
throw new COMException("Cannot obtain ISampleGrabber");
}
{
AMMediaType mt = new AMMediaType();
mt.majorType = DirectShowLib.MediaType.Audio;
mt.subType = DirectShowLib.MediaSubType.PCM;
hr = audioGrabber.SetMediaType(mt);
DsError.ThrowExceptionForHR(hr);
DsUtils.FreeAMMediaType(mt);
}
hr = ConnectSampleGrabber(graph, sourceF, audioGrabberFilter);
if (0 != hr)
{
// Cannot connect the audio grabber. Remove the filter from the graph.
hr = graph.RemoveFilter(audioGrabberFilter);
DsError.ThrowExceptionForHR(hr);
Util.ReleaseComObject(ref audioGrabberFilter);
audioGrabber = null;
return;
}
audioNullFilter = new NullRenderer() as IBaseFilter;
if (audioNullFilter == null)
{
throw new COMException("Cannot create NullRenderer");
}
hr = graph.AddFilter(audioNullFilter, "Null Filter");
DsError.ThrowExceptionForHR(hr);
hr = Util.ConnectFilters(graph, audioGrabberFilter, audioNullFilter);
DsError.ThrowExceptionForHR(hr);
audioGrabberCB = new SampleGrabberCB();
hr = audioGrabber.SetCallback(audioGrabberCB, (int)CBMethod.Sample);
DsError.ThrowExceptionForHR(hr);
}
public void Reset()
{
mediaControl = null;
mediaEvent = null;
Util.ReleaseComObject(ref graph);
Util.ReleaseComObject(ref videoGrabberFilter);
videoGrabber = null;
Util.ReleaseComObject(ref videoNullFilter);
videoGrabberCB = null;
Util.ReleaseComObject(ref audioGrabberFilter);
audioGrabber = null;
Util.ReleaseComObject(ref audioNullFilter);
audioGrabberCB = null;
}