Comment by HanClinto

I built one of these several years ago for MtG cards. Trained a neural network with a binary classifier on a cheap $20 USB microscope looking at examples of the backs of real cards vs. fake cards.

https://youtu.be/6_kKR7YgPF4

Sadly never got around to shipping it, because it worked really well. Ported it to the web, but never figured out the billing issue, and so it died during the delivery phase. From time-to-time, I still wonder if I should resurrect this project, because I think it could help a lot of people.