ICM_COMPRESS_GET_SIZE

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The ICM_COMPRESS_GET_SIZE message requests that the video compression driver supply the maximum size of one frame of data when compressed into the specified output format. You can send this message explicitly or by using the ICCompressGetSize macro.

ICM_COMPRESS_GET_SIZE 
wParam = (DWORD) (LPVOID) lpbiInput; 
lParam = (DWORD) (LPVOID) lpbiOutput;

Parameters

lpbiInput

Pointer to a BITMAPINFO structure containing the input format.

lpbiOutput

Pointer to a BITMAPINFO structure containing the output format.

Return Values

Returns the maximum number of bytes a single compressed frame can occupy.

Remarks

Typically, applications send this message to determine how large a buffer to allocate for the compressed frame.

The driver should calculate the size of the largest possible frame based on the input and output formats.

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, BITMAPINFO, ICCompressGetSize