Edit

ICM_DRAW_BEGIN message

  • Article

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

Pointer to an ICDRAWBEGIN structure containing the input format.

lParam

Size, in bytes, of ICDRAWBEGIN.

Return Value

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.

Value Meaning
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.

Requirements

Requirement Value
Minimum supported client
 Windows 2000 Professional [desktop apps only]
Minimum supported server
 Windows 2000 Server [desktop apps only]
Header
Vfw.h

See also

Video Compression Manager

Video Compression Messages