I've been pouring over the forums for answers to get the kind of background subtraction I'm talking about, but to no avail. Photobooth does a pretty great job of subtracting the background from your video once taking a clean sample, and I'd like to replicate that same functionality in Max.
I'm building a live installation that'll comp people that are in front of a green screen into historical footage at a party. Now, of course chromakey seems like the best choice here, but it's not going to be a perfect green screen, so a difference matte seemed like a good compromise in imperfect conditions. It will be shadowless and the lighting will be controlled, and the camera firmly mounted, but I'm sure it won't be a perfect clean green. Any ideas? The jit.op @op absdiff thing doesn't really do what I want, because it's still sort of compositing over the background rather than just replacing it with an alpha channel.