How to Transcribe Color of Certain Pixels onto a Form? (Mosaic Animation)

Hi Community,

i could really use your Help.

for an exhibition next wednesday i'm working on a distortion method for videos which should end up with something like a 12:9 pixel mosaic whose colors have their equivalent in certain pixels of an original video. SO they should change color just like the chosen pixel of the original. Animated color Palettes if you like.

I know there are filters for mosaic, but i'd like to control the primal color area for each square.

Is it possible to Zoom that far and then align as much copies of the video?

or are expressions the key?

unfortunately i'm not used to work with AE, so i'd appreciate easy help :)