ICDecompressBegin

The ICDecompressBegin macro notifies a video decompression driver to prepare to decompress data. You can use this macro or explicitly call the ICM_DECOMPRESS_BEGIN message.

DWORD ICDecompressBegin(
  hic,        
  lpbiInput,  
  lpbiOutput  
);
 

Parameters

hic

Handle of a decompressor.

lpbiInput

Address of a BITMAPINFO structure containing the input format.

lpbiOutput

Address of a BITMAPINFO structure containing the output format.

Return Values

Returns ICERR_OK if the specified decompression is supported or ICERR_BADFORMAT otherwise.

Remarks

When the driver receives this message, it should allocate buffers and do any time-consuming operations so that it can process ICM_DECOMPRESS messages efficiently.

The ICDecompressBegin and ICDecompressEnd macros do not nest. If your driver receives ICM_DECOMPRESS_BEGIN before decompression is stopped with ICM_DECOMPRESS_END, it should restart decompression with new parameters.

QuickInfo

  Windows NT: Requires version 3.1 or later.
  Windows: Requires Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in vfw.h.

See Also

Video Compression Manager Overview, Video Compression Macros, BITMAPINFO, ICDecompressEnd, ICM_DECOMPRESS, ICM_DECOMPRESS_BEGIN, ICM_DECOMPRESS_END