Ask HN: App to locate the position of a book on shelf?

My son has 100s of books on his shelves. I want to locate a particular book. I'm certain of the name, and certain that the name is on the spine. It seems feasible to have an app where you can: 1. Enter some text you want to search for. 2. Scan some shelves by waving your phone around. 3. See a still photo with the matching book(s) highlighted. Do you know of such an app? I know I could take some photos of the shelves, transfer them to my computer, use OCR and save them as a searchable PDF, but it seems like more effort than it should be.