This topic documents a feature of Visual Filters and Transitions, which is deprecated as of Windows Internet Explorer 9 and obsolete as of Internet Explorer 10.
Retrieves the native pixel format of the surface.
virtual DXSAMPLEFORMATENUM SampleFormatEnum(VOID) = 0;
Procedural surfaces should return DXPF_NONSTANDARD. This indicates that users cannot get direct access to the samples because they are procedurally generated when read. This is all that is needed if the output samples will always have an alpha value of 255. If the output samples can have alpha values of 0 or 255, then the DXPF_TRANSPARENCY flag should be set for the return value. If the output samples can have alpha values ranging from 0 through 255, then the DXPF_TRANSLUCENCY flag should be set as well. This information is used to optimize sample processing in other routines.