ICM_GETBUFFERSWANTED
The
ICM_GETBUFFERSWANTED message queries a driver for the number of buffers to
allocate. You can send this message explicitly or by using the ICGetBuffersWanted macro.
ICM_GETBUFFERSWANTED
wParam = (DWORD) (LPVOID) lpdwBuffers;
lParam = 0;
Parameters
lpdwBuffers
Address to
contain the number of samples the driver needs to efficiently render the data.
Return Values
Returns
ICERR_OK if successful or ICERR_UNSUPPORTED otherwise.
Remarks
This message
is used by drivers that use hardware to render data and want to ensure a
minimal time lag caused by waiting for buffers to arrive. For example, if a
driver controls a video decompression board that can hold 10 frames of video,
it could return 10 for this message. This instructs applications to try to stay
10 frames ahead of the frame it currently needs.
See Also