@trich1
yes side of the frame works. just needs to be possible to move the finger into the Infrared light grid it creates ;)
However when you really want a photobooth with basically only the feature make a photo a small gesture sensor or a distance sensor (depending on how you want to trigger) would be a lot cheaper since touch foils are damn expensive in that size (never used one with a mirror but some producers state that some touch foils work with their mirror). And even a IR Frame will probably cost at least around 100$ I guess. Although I am no big fan of the touch + mirror combo anyways because you have fingerprints all over the mirror ^^ which you do not have with gesture control (maybe voice control would be cool aswell :) )
Well but back to your question I never used a IR Frame so far but in general mapping should be quite possible. But you need to check what options are out there for your distro. It appears to be pretty common that you need to map for example with multiple monitors since linux often sees them as one so mapping needs to be done here aswell.
Just search for touchscreen calibration and you should find explanations