private WebcamFormat[] GetWebcamFormats(string webcamId, bool filter, bool exact, int minWidth, int minHeight, float minFrameRate)
{
List <WebcamFormat> list = null;
HResult result = GetMediaSource(webcamId, out IMFMediaSource source);
if (result == Player.NO_ERROR)
{
result = MFExtern.MFCreateSourceReaderFromMediaSource(source, null, out IMFSourceReader reader);
if (result == Player.NO_ERROR)
{
HResult readResult = Player.NO_ERROR;
int streamIndex = 0;
int typeIndex = 0;
float frameRate = 0;
bool match;
list = new List <WebcamFormat>(250);
while (readResult == Player.NO_ERROR)
{
readResult = reader.GetNativeMediaType(streamIndex, typeIndex, out IMFMediaType type);
if (readResult == Player.NO_ERROR)
{
MFExtern.MFGetAttributeRatio(type, MFAttributesClsid.MF_MT_FRAME_RATE, out int num, out int denum);
if (denum > 0)
{
frameRate = (float)num / denum;
}
MFExtern.MFGetAttributeRatio(type, MFAttributesClsid.MF_MT_FRAME_SIZE, out int width, out int height);
match = true;
if (filter)
{
if (exact)
{
if ((minWidth != -1 && width != minWidth) || (minHeight != -1 && height != minHeight) || (minFrameRate != -1 && frameRate != minFrameRate))
{
match = false;
}
}
else if ((minWidth != -1 && width < minWidth) || (minHeight != -1 && height < minHeight) || (minFrameRate != -1 && frameRate < minFrameRate))
{
match = false;
}
}
if (match && !FormatExists(list, width, height, frameRate))
{
list.Add(new WebcamFormat(streamIndex, typeIndex, width, height, frameRate));
}
typeIndex++;
Marshal.ReleaseComObject(type);
}
// read formats of 1 track (stream) only - can't switch tracks (?)
//else if (readResult == HResult.MF_E_NO_MORE_TYPES)
//{
// readResult = Player.NO_ERROR;
// streamIndex++;
// typeIndex = 0;
//}
}
if (reader != null)
{
Marshal.ReleaseComObject(reader);
}
}
if (source != null)
{
Marshal.ReleaseComObject(source);
}
}
_base._lastError = result;
return((list == null || list.Count == 0) ? null : list.ToArray());
}
