Requirements for a GFX Filter Factory
Register its device interface in both the KSCATEGORY_AUDIO and KSCATEGORY_DATATRANSFORM device classes.
Have only one input pin and one output pin.
Add a Gfx subkey to the filter's KSCATEGORY_AUDIO device interface registry key. The device setup information file for the filter factory typically uses an INF AddReg directive to add the Gfx subkey to the registry path during driver installation.
Build date: 11/16/2013