Hi!
Nothing about "video motion"... but I've wanted to play with this idea of "cartoons blocks"
But not a complex algorithm here! Nor a simple one. Just the great Snap! primitives 
The great "paste on" block
Over a moving shape with some effects
And more animation
Yes! Just five minutes of fun (not hard here 
) tinkering. With more "thinkering" you can do whatever you want (maybe with more "hard" fun).
Joan
Joan, your ingenuity left us all speechless.
I guess.
Because we all were probably thinking, ok, I won't speak for others, but I know I did: "Why didn't I think of this?!, Wow!"
I like how you put to use the more or less 'useless' "fisheye effect" block I wouldn't think of in million years to use, and combining it with "paste on" is beautiful.
I'm curious is there any particular reason why you set the "whirl" effect to 100?
Thanks @kinestheticlearning,
It's not so much innovation 
! I guess Jens created "paste on" block thinking on effects like this.
I remember a year ago, in Olot, creating the "video snap on sprite" block with Jens and Josep... and wow! Just this brilliant idea to snap/paste on other sprite (and not only over stage) that allows us to create effects in a part (a mobile part, with any shape we want) of a picture (first of a video snap and later of any costume).
And with this last block, paste on, as both images are mobile, the possibilities can be multiplied. This is clearly shown in Jens's examples.
This year we will miss Olot ... but for sure we will continue to do great (and fun) things.
Joan
Ya need HYPerbLOCks
Yeah, now that we have them, you can use them instead of MAP block. Will you do it?
Woah. That is cool.
ok
It doesnt mark errors in red,it marks correct colors in white!
The 2 costumes should have the same size,or you will see noise.
ok ;~P