/// <summary>
/// Create new FrameGrabber from GetFrame object.
/// </summary>
/// <param name="getFrameObj">
/// GetFrame object to create FrameGrabber.
/// </param>
/// <param name="streamInfo">
/// Information about stream in <see cref="SARA.Avi.AviMarshal.AVISTREAMINFO"/> structure
/// </param>
internal FrameGrabber(IntPtr getFrameObj, AVISTREAMINFO streamInfo)
{
if (getFrameObj == IntPtr.Zero)
throw new AviException("Can not create FrameGrabber from null GetFrame object.");
_getFrameObj = getFrameObj;
_streamInfo = streamInfo;
AviFil32.AVIFileInit();
}
/// <summary>
/// Avi stream constructor.
/// </summary>
/// <param name="aviStream">
/// Handle to AviFil32 avi stream.
/// </param>
/// <param name="streamInfo">
/// Stream info header.
/// </param>
internal AviStream(IntPtr aviStream, AVISTREAMINFO streamInfo)
{
if (aviStream == IntPtr.Zero)
throw new AviException("Can not create avi stream from null stream");
_aviStream = aviStream;
_streamInfo = streamInfo;
AviFil32.AVIFileInit();
}
/// <summary>
/// AudioStream constructor.
/// </summary>
/// <param name="aviStream">
/// Handle to AviFil32 avi stream.
/// </param>
/// <param name="streamInfo">
/// Stream info header.
/// </param>
internal AudioStream(IntPtr aviStream, AVISTREAMINFO streamInfo)
: base(aviStream, streamInfo)
{
if (streamInfo.fccType != AviFil32.StreamType.AUDIO)
{
AviFil32.AVIStreamRelease(_aviStream);
AviFil32.AVIFileExit();
_aviStream = IntPtr.Zero;
throw new AviException("Can not create audio stream from not audio stream.");
}
}
/// <summary>
/// Get avi stream from AviFile.
/// </summary>
/// <param name="id">
/// Stream id.
/// </param>
/// <returns>
/// Avi stream or null when stream does not exist.
/// </returns>
public AviStream GetStream(int id)
{
IntPtr aviStream = new IntPtr();
AVISTREAMINFO streamInfo = new AVISTREAMINFO();
AviFil32.AVIError error = AviFil32.AVIFileGetStream(_aviFile, ref aviStream, AviFil32.StreamType.ANY, id);
if (error != AviFil32.AVIError.AVIERR_OK)
{
switch (error)
{
case AviFil32.AVIError.AVIERR_NODATA:
throw new AviException("The file does not contain a stream corresponding to specified values.");
case AviFil32.AVIError.AVIERR_MEMORY:
throw new AviException("Not enough memory.");
default:
throw new AviException("Unrecognised AVI exception (0x" + Convert.ToString((int)error, 16) + ").");
}
}
if (aviStream == IntPtr.Zero)
return null;
error = AviFil32.AVIStreamInfo(aviStream, ref streamInfo, Marshal.SizeOf(streamInfo));
if (error != AviFil32.AVIError.AVIERR_OK)
throw new AviException("Unrecognised AVI exception (0x" + Convert.ToString((int)error, 16) + ").");
switch (streamInfo.fccType)
{
case AviFil32.StreamType.AUDIO:
return new AudioStream(aviStream, streamInfo);
case AviFil32.StreamType.MIDI:
return new MidiStream(aviStream, streamInfo);
case AviFil32.StreamType.TEXT:
return new TextStream(aviStream, streamInfo);
case AviFil32.StreamType.VIDEO:
return new VideoStream(aviStream, streamInfo);
default:
throw new AviException("Unknown stream type (0x" + Convert.ToString((int)streamInfo.fccType, 16) + ").");
}
}
public static extern AVIError AVIStreamInfo(IntPtr pavi, ref AVISTREAMINFO psi, int lSize);
