Python: Converting GIF frames to PNG

I don't think you're doing anything wrong. See a similar issue here: animated GIF problem. It appears as if the palette information isn't correctly treated for later frames. The following works for me:

def iter_frames(im):
    try:
        i= 0
        while 1:
            im.seek(i)
            imframe = im.copy()
            if i == 0: 
                palette = imframe.getpalette()
            else:
                imframe.putpalette(palette)
            yield imframe
            i += 1
    except EOFError:
        pass

for i, frame in enumerate(iter_frames(im)):
    frame.save('test%d.png' % i,**frame.info)

I've fixed this bug here https://code.launchpad.net/~asdfghjkl-deactivatedaccount1/python-imaging/gif-fix.

DSM's answer won't work if the GIF uses local color tables.