Can I make an image adjust in size to fit a power window?

Hi all!
I'm currently doing a video project for uni, and it's the first one I've ever worked on. What I can't wrap my head around is how to get still images to fit to a power window.
We have these empty picture frames (with green cardboard in them for good measure) and we'd like to show an image as if it were part of the frame (which of course also means having it move with the frame).
I can get the power window to track perfectly, but the image inside is always a part of the image I want to show. Is there any way to fix this?
Thanks in advance!
I'm currently doing a video project for uni, and it's the first one I've ever worked on. What I can't wrap my head around is how to get still images to fit to a power window.
We have these empty picture frames (with green cardboard in them for good measure) and we'd like to show an image as if it were part of the frame (which of course also means having it move with the frame).
I can get the power window to track perfectly, but the image inside is always a part of the image I want to show. Is there any way to fix this?
Thanks in advance!