I just downloaded Image Comparer, and it's working wonderfully!
The only problem I've been having, however, makes the software not quite up to par with what I need it for
The software seems to have minimum dimensions. It doesn't mention anything, but a lot of my smaller images just aren't being added to the galleries along with the rest.
If I scale them to be large enough, then they return 0% for the rest of the images (even if I know there should be a 100% match).
What are the actual minimum dimensions, and is there a way around that?