Earlier quoted context omitted.
Would also be interesting to see if they could recreate the effect of the original video in JS also.
Isn't the algorithm just, filter out the greenscreen, for each remaining pixel draw it to the buffer, draw the buffer to the screen? That doesn't seem more complicated than the examples they showed.
"Would also be interesting" and "fun to compare" give no implication of relative difficulty. I would like to see the algorithm though so please post the code if you get it working in JS! That would be awesome!