Comment by Imnimo

It's tough to judge without seeing examples of the targets and the user photos, but I'm curious if this could be done with just old-school SIFT. If it really is exactly the same image in the in the corpus and on the wall, does a neural embedding model really buy you a lot? A small number of high confidence tie points seems like it'd be all you need, but it probably depends a lot on just how challenging the user photos are.