I worked with perceptual hashes. The false positive rate makes it unusable. Even when combined with AI it does not work well. It can get you a list of possible

I worked with perceptual hashes. The false positive rate makes it unusable. Even when combined with AI it does not work well. It can get you a list of possible matches, but only a human can really tell if the image is the image. Then you have a problem of images not making to the list. That was in 2016. Maybe things changed.