ICM_DRAW_BEGIN

The ICM_DRAW_BEGIN message notifies a rendering driver to prepare to draw data. 

ICM_DRAW_BEGIN 
wParam = (DWORD) (LPVOID) &icdrwBgn; 
lParam = sizeof(ICDRAW);

Parameters

icdrwBgn
Address of an ICDRAWBEGIN structure containing the input format.
lParam
Size, in bytes, of ICDRAWBEGIN.

Return Values

Returns ICERR_OK if the driver supports drawing the data to the screen in the specified manner and format, or an error code otherwise. Possible error values include the following:

ICERR_BADFORMAT Input or output format is not supported.
ICERR_NOTSUPPORTED Driver does not draw directly to the screen or does not support this message.

Remarks

If you want the driver to decompress data into a buffer, send the ICM_DECOMPRESS_BEGIN message.

The ICM_DRAW_BEGIN and ICM_DRAW_END messages do not nest. If your driver receives ICM_DRAW_BEGIN before decompression is stopped with ICM_DRAW_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 Messages, ICDRAWBEGIN, ICM_DECOMPRESS_BEGIN, ICM_DRAW_END