More fooling with video last night. Virtualdub-MPEG2 can convert mpeg to divx, but in my hands the converted files are five times bigger than with Dr. DivX. Dr. DivX doesn’t have a command-line interface, but can be automated using a class a tools that record and replay mouse actions. I experimented a bit with Phantom Test Driver, which is inexpensive ($40) and works pretty well.