Guliverkli2

I'm trying to find the best way to do combination AR and crops on really badly encoded videos. For example, I have been finding clips that have two sets of "black bars". so the source needs to be custom-cropped, then AR-corrected to 16:9. I have been playing with pan&scan zoom presets, and it works great, but somehow the AR correction only addresses the original resolution of the clip. So It still doesn't look right

So, is it possible to do this kind of thing using shader filters, or am i stuck having to whip up an AVIsynth each time? Is there a convenient way to do that?