ICM_DECOMPRESS_GET_PALETTE

The ICM_DECOMPRESS_GET_PALETTE message is sent to a video decompression driver to obtain the color table of the output BITMAPINFOHEADER structure.

Parameters

dwParam1

Specifies a pointer to a BITMAPINFOHEADER data structure indicating the input format.

dwParam2

Specifies zero or a pointer to a BITMAPINFOHEADER data structure used to return the color table. The space reserved for the color table is always at least 256 colors.

Return Value

Returns the size of the output format or an error code.

Comments

If dwParam2 is zero, the driver returns only the size of the output format. Applications specify zero to determine the size of the output format.

If dwParam2 is nonzero, the driver sets the biClrUsed member of the BITMAPINFOHEADER data structure to the number of colors in the color table. The driver fills the bmiColors members of the BITMAPINFO data structure with the actual colors.

The driver should support this message only if it uses a palette other than the one specified in the input format.