Re: codejunky Erm
Even easier just to make a facial recog map of the face from the banned pic and use that to stop an future repostings, especially as miscreants will try to edit the original pic to get round the first check.
Sorry, but no, facial recognition cannot be used for this. It is a very unreliable technology and despite the rubbish and lies from those who sell such systems, and the likes of Gartner who repeat them, it is not very much a solution to anything. Even in limited datasets, where you have the identities and profiles of a small number of individuals, match accuracy is low. As soon as you extend it out to hundreds, let alone thousands of profiles the error rate will be so high as to make the system almost useless.