private void WriteHeaders()
{
const uint AVIF_HASINDEX = 0x00000010;
const uint AVIF_ISINTERLEAVED = 0x00000100;
AVIMAINHEADER aviH = new AVIMAINHEADER();
AVIStream vidStr = _streamList[_videoStreamID];
AVISTREAMHEADER vidStrH = vidStr.Header;
BITMAPINFOHEADER vidStrF = vidStr.VideoFormat;
if (vidStrH.dwRate != 0)
{
aviH.dwMicroSecPerFrame = Convert.ToUInt32(((double)vidStrH.dwScale / vidStrH.dwRate) * 1000000.0);
}
aviH.dwFlags = AVIF_HASINDEX | AVIF_ISINTERLEAVED;
aviH.dwTotalFrames = (uint)vidStr.ChunksInFirstMOVI;
aviH.dwStreams = (uint)_streamList.Count;
aviH.dwWidth = (uint)vidStrF.biWidth;
aviH.dwHeight = (uint)Math.Abs(vidStrF.biHeight);
Seek(_avihOffset);
WriteChunk("avih", StructHelper <AVIMAINHEADER> .ToBytes(aviH, false));
for (int i = 0; i < _streamList.Count; i++)
{
AVIStream s = _streamList[i];
AVISTREAMHEADER sHeader = s.Header;
sHeader.dwLength = (s.Type == AVIStreamType.Video) ? (uint)s.ChunkList.Count :
CalculateDuration(s.ChunkList, 0, s.ChunkList.Count);
sHeader.dwSuggestedBufferSize = FindLargestChunk(s.ChunkList);
Seek(s.STRHOffset);
WriteChunk("strh", StructHelper <AVISTREAMHEADER> .ToBytes(sHeader, false));
Seek(s.STRFOffset);
WriteChunk("strf", s.MakeSTRFChunk());
if (s.OpenDMLSuperIndex != null)
{
Seek(s.INDXOffset);
WriteChunk("indx", s.OpenDMLSuperIndex);
}
}
Seek(_dmlhOffset);
WriteChunk("dmlh", MakeDMLHChunk((uint)vidStr.ChunkList.Count));
}
private void StartFile()
{
if (_videoStreamID == -1)
{
throw new Exception("AVI must have a video stream.");
}
_isFileStarted = true;
_riffOffset = StartList("RIFF", "AVI ");
StartList("LIST", "hdrl");
_avihOffset = WriteChunk("avih", (uint)StructHelper <AVIMAINHEADER> .SizeOf);
for (int i = 0; i < _streamList.Count; i++)
{
AVIStream s = _streamList[i];
StartList("LIST", "strl");
s.STRHOffset = WriteChunk("strh", (uint)StructHelper <AVISTREAMHEADER> .SizeOf);
s.STRFOffset = WriteChunk("strf", s.MakeSTRFChunk());
if (s.STRNData != null)
{
WriteChunk("strn", s.STRNData);
}
s.INDXOffset = WriteChunk("JUNK", OpenDMLSuperIndexSize(MaxOpenDMLSuperIndexEntries));
EndList();
}
StartList("LIST", "odml");
_dmlhOffset = WriteChunk("dmlh", MakeDMLHChunk(0));
EndList();
EndList(); // 'hdrl'
// Pad to a multiple of 2K (8K at least)
if ((_fileOffset < 8192) || ((_fileOffset % 2048) != 0))
{
int paddingStart = (int)_fileOffset + 8;
int toNext2K = (2048 - (paddingStart % 2048)) % 2048;
int to8K = 8192 - paddingStart;
WriteChunk("JUNK", (uint)Math.Max(to8K, toNext2K));
}
_moviOffset = StartList("LIST", "movi");
}