Yeah, my thinking is that you'd import one large image (PNG, I guess) and then from that create frames of animation, and then for each frame, outputs something in XML which has the source XY from the large image, and the destination XY on the screen.
That way you can make quite complicated animations reasonably easily, and you just have the 1 image to load.
From doing some googling, I've found one program called Sprite Vortex but it's not finished, let's say.
Thanks