BOOL
VC_SetKeyColourPalIdx(
VCUSER_HANDLE vh,
WORD PaletteIndex
);
The VC_SetKeyColourPalIdx function requests a kernel-mode video capture driver to set the overlay destination image’s key color to a specified palette index.
Returns TRUE if the operation succeeds. Otherwise returns FALSE.
Before setting the key color, the driver should call VC_GetOverlayMode and test the VCO_KEYCOLOUR_FIXED flag to determine if the key color can be set. If the color can be set, the driver should test the VCO_KEYCOLOUR_RGB flag to determine if, based on the current data format, the kernel-mode driver stores the key color as an RGB color or as a palette index number. If the key color is stored as an RGB color, the driver should call VC_SetKeyColourRGB to set it. If the key color is stored as a palette index, the driver should call VC_SetKeyColourPalIdx to set it.
The VC_SetKeyColourPalIdx function calls DeviceIoControl (described in the Win32 SDK) to send an IOCTL_VIDC_SET_KEY_PALIDX control code to the specified kernel-mode driver. When a kernel-mode driver using VCKernel.lib receives this control code, its SetKeyPalIdxFunc function is called.