ICM_DRAW_SUGGESTFORMAT

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The ICM_DRAW_SUGGESTFORMAT message queries a rendering driver to suggest a decompressed format that it can draw.

ICM_DRAW_SUGGESTFORMAT 
wParam = (DWORD) (LPVOID) &icdrwSuggest; 
lParam = sizeof(ICDRAWSUGGEST);

Parameters

icdrwSuggest

Pointer to an ICDRAWSUGGEST structure.

lParam

Size, in bytes, of ICDRAWSUGGEST.

Return Values

Returns ICERR_OK if successful. If the lpbiSuggest member of the ICDRAWSUGGEST structure is NULL, this message returns the amount of memory required to contain the suggested format.

Remarks

The driver should examine the format specified in the lpbiIn member of the ICDRAWSUGGEST structure and use the lpbiSuggest member to return a format it can draw. The output format should preserve as much data as possible from the input format.

Optionally, the driver can use the installable compressor handle passed in the hicDecompressor member of ICDRAWSUGGEST to make more complex selections. For example, if the input format is 24-bit JPEG data, a renderer could query the decompressor to find out if it can decompress to a YUV format (which might be drawn more efficiently) before selecting the format to suggest.

Requirements

**  Windows NT/2000/XP:** Included in Windows NT 3.1 and later.
**  Windows 95/98/Me:** Included in Windows 95 and later.
**  Header:** Declared in Vfw.h.

See Also

Video Compression Manager, Video Compression Messages, ICDRAWSUGGEST