But how??

They took the image from the moment the frame was over the can and transplanted it onto the frame via photoshop afterwards. It's an empty frame.

You just destroyed the illusion, thus destroying my question for the night

Here's another one. How'd they get the cat to stand still for them to put the frame around it? It obviously waited until the far edge hit the ground before stepping over it. How did they get it to do that?

Look at the cat and the frame's shadow.