IOverlay::SetColorKey method (strmif.h)

The SetColorKey method changes the color key.


HRESULT SetColorKey(
  COLORKEY *pColorKey



Pointer to the color key value to be set. If successful, the actual color key value selected is copied to this parameter.

Return value

Returns S_OK if successful, E_POINTER if pColorKey is NULL, or E_INVALIDARG if the value of pColorKey is invalid for the current palette or pixel format.


If you change the color key using the SetColorKey method, all the advise links will receive an IOverlayNotify::OnColorKeyChange callback method with the new color.

When using IOverlay::Advise on a palettized display, a filter can either install a color key (using SetColorKey) or install a palette (using IOverlay::SetPalette), but not both. This is because color keys in this mode require a palette to be realized that would conflict with SetPalette. Color keys can be uninstalled by requesting a color key with the CK_NOCOLORKEY flag. Likewise, any palette installed through SetPalette can be uninstalled by calling SetPalette and passing in NULL parameters (that is, SetPalette(0,NULL)).

Trying to set a palette when a color key is installed returns a VFW_E_PALETTE_SET error. Trying to set a color key when a palette is installed returns VFW_E_COLOR_KEY_SET.


Minimum supported client Windows 2000 Professional [desktop apps only]
Minimum supported server Windows 2000 Server [desktop apps only]
Target Platform Windows
Header strmif.h (include Dshow.h)
Library Strmiids.lib

See also

Error and Success Codes

IOverlay Interface