> You'd think they would move to a better hash function by now MD5 is (relatively) fast, and a (relatively) small datapoint to store. You're definitely wanting

> You'd think they would move to a better hash function by now MD5 is (relatively) fast, and a (relatively) small datapoint to store. You're definitely wanting to store a lot of data points too; it's so so much easier to scan and de-scope OK images..... The MD5 catalogue's intent is to allow quick identification of suspect material to drop to manual review (little bit of inference there from what I have read about Google, but I'd be shocked if that wasn't true - false positives in this context are not as bad as true positives [of course] but accusing an innocent person of having child porn is damaging). From the GP: >That has to be the worst job ever. It is. I did it for a while working for a computer forensics firm. Not even slightly pleasant. We used to go through millions of images - to be honest, 99.999999999% of it was "normal" (if often slightly wierd) porn. You do become detached from it after a while. To be honest; the chats/emails grooming young people were the worst.