Override Pin Member Functions (Windows CE 5.0)
If you derived your filter class from the transform classes and want more than one input or output pin, you must override the pin class (for example, CTransformInputPin or CTransformOutputPin).
If you override the pin class, you must also override the GetPin member function of CTransformFilter or CTransInPlaceFilter, so that you can create pin objects from your derived classes.
If you override one of the pin classes (for example, CTransformInputPin) and override GetPin to create the pin object, you must also override GetPin to create the other pin object of the same base class (for example, CTransformOutputPin).
If you want more than one input or output pin, it is often simpler to derive your filter from CBaseFilter rather than from one of the transform classes.
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