I need a free or open source software that could edit AVIs by painting on to them. or by taking a jpeg or png sequence and painting on it.
GIMP Animation Package
Cinepaint
- OR -
I haven’t tried it, but if you’re able to get your avi into a video editor and export it as a filmstrip file, you might be able to load that into the GIMP or something similar.
i got gimp animation package but how do u install/run it 
i got GAP installed waht now
Um… load an image from your sequence (pngs or jpgs or whatever) into the GIMP. Do what you want to it. Then go to “Video” in your menu (it’s either top-most, or in your plugins or filters… I’d be more clear, but I’m at work and I don’t have a copy of GIMP readily available). There should be an option that says “Next Frame”. Click it and your current changes will be saved as the next frame is brought into the window.
To the best of my memory, that’s how it’s done. With some clever scripting, you can even get some pretty good post-processed effects on your animation. I did.
filmgimp is pretty hit and miss if you’re on windows. it won’t work on my machine. if you can’t get it to run, just use irfanview to “extract all frames”, and when you’re finished painting, load the sequence into blender sequence editor ( shift A ), set frames number in render buttons, press ‘do sequence’, and select the desired format ( one of the .avi codecs i assume is what you would want ) , then hit animate. irfanview also does batch processing.
JAHSHAKA! I think that wil l work very nicely for ya. Still in development, but worth a look. GAP aughta work well too.