Bad Apple, but only the difference to the previous frame

You can only see the difference to the previous frame. Gray means that the color didn't change between the frames, black means it changed from white to black, and white means it changed from black to white. Things that don't move (e.g. the orb at 1:38) become invisible because of this. This should in theory work with any video, but I think Bad Apple shows this effect best. The effect was made in Blender using compositor nodes. And no, I did not see Posy's video until after I made mine, but both use the same effect. Posy's video:    • Motion Extraction   Music: "Bad Apple!!" by Alstroemeria Records