Well, I think it’s one of two things:
1. The BG (cork) IS a high res image, or it’s a bunch of normal res images arranged and parented to each other. Then all the other elements are just pictures or matted video clips and thumnail tack images all parented to a master null which is animated around and everything follows it. The camera never moves, but kind of bobs up and down while everything moves below it.
2. It’s a simple magic trick. You assume that the cork board is full when it’s really a small space and as we see one group of shots, the other area of the cork board is switched to something else. And so on.
Chris Smith
https://www.sugarfilmproduction.com