I've been given the task of making dvds from 50 avi's.
These have been previously compressed (no problem) but also have been letterboxed.
They're all 352x240, but of various AR's as seen in these 3 examples:



I'm used to using virtualdub for all my editing, but now I'm at a loss.
How do I crop/resize, whatever all these different videos, to get the right AR during encoding?
I can encode to whatever mpeg AR I need, half D1, or even 352x240/288.
Please give me some hints on removing the black bars, and getting the correct AR input (via frameserving) to an encoder.