I developed the first version of the screening system for a corporation about 10 years ago, when UGC was still in its infancy. We had the help of a Microsoft to

I developed the first version of the screening system for a corporation about 10 years ago, when UGC was still in its infancy. We had the help of a Microsoft tool that would match the visual fingerprint of a photo against a known-images database that prevented human operators from re-seeing an already tagged image in a different cloud, hoping to reduce the psychological scarring of the human workers that screened the content. We also evaluated automatic classification of images, but it's very hard to detect soft core porn from shock images even with today's algos, never mind 10 years ago. One advice from a legal counsel that I received at that time still stands in my memory; she said: "Never look at the images, nevermind how curious you are. It's not just illegal and can land you in prison, but it's permanent. You cannot un-see something you've seen."