/// <summary>Initialize a VideoStream for an existing stream</summary>
/// <param name="aviFile">The file that contains the stream</param>
/// <param name="aviStream">An IAVISTREAM from [aviFile]</param>
public VideoStream(int aviFile, IntPtr aviStream)
{
this.aviFile = aviFile;
this.aviStream = aviStream;
Avi.AVISTREAMINFO streamInfo = GetStreamInfo(aviStream);
//Avi.BITMAPINFOHEADER bih = new Avi.BITMAPINFOHEADER();
//int size = Marshal.SizeOf(bih);
Avi.BITMAPINFO bih = new Avi.BITMAPINFO();
int size = Marshal.SizeOf(bih.bmiHeader);
Avi.AVIStreamReadFormat(aviStream, 0, ref bih, ref size);
if (bih.bmiHeader.biBitCount < 24)
{
size = Marshal.SizeOf(bih.bmiHeader) + Avi.PALETTE_SIZE;
Avi.AVIStreamReadFormat(aviStream, 0, ref bih, ref size);
CopyPalette(bih.bmiColors);
}
this.frameRate = (float)streamInfo.dwRate / (float)streamInfo.dwScale;
this.width = (int)streamInfo.rcFrame.right;
this.height = (int)streamInfo.rcFrame.bottom;
this.frameSize = bih.bmiHeader.biSizeImage;
this.countBitsPerPixel = bih.bmiHeader.biBitCount;
this.firstFrame = Avi.AVIStreamStart(aviStream.ToInt32());
this.countFrames = Avi.AVIStreamLength(aviStream.ToInt32());
}
/// <summary>Returns all data needed to copy the stream</summary>
/// <remarks>Do not forget to call Marshal.FreeHGlobal and release the raw data pointer</remarks>
/// <param name="streamInfo">Receives the header information</param>
/// <param name="format">Receives the format</param>
/// <param name="streamLength">Receives the length of the stream</param>
/// <returns>Pointer to the wave data</returns>
public IntPtr GetStreamData(ref Avi.AVISTREAMINFO streamInfo, ref Avi.PCMWAVEFORMAT format, ref int streamLength)
{
streamInfo = GetStreamInfo();
format = GetFormat();
//length in bytes = length in samples * length of a sample
streamLength = Avi.AVIStreamLength(aviStream.ToInt32()) * streamInfo.dwSampleSize;
IntPtr waveData = Marshal.AllocHGlobal(streamLength);
int result = Avi.AVIStreamRead(aviStream, 0, streamLength, waveData, streamLength, 0, 0);
if (result != 0)
{
throw new Exception("Exception in AVIStreamRead: " + result.ToString());
}
return(waveData);
}