How can program know if a photo was edited or not? My question stems from the experience that one website (World Cup Fan ID) automatically rejects any photo that was edited but accepts not edited photo. How does it work?

closed as off-topic by flolilolilo, Tetsujin, Hueco, inkista, Michael C Jun 13 '18 at 0:58

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  • What site (URI) exactly is World Cup Fan ID? As to the question: They probably just see if the metadata contain any software-tags - that's the only way I can think of how this would work, but still, it offers more loopholes than safety and/or precision. – flolilolilo Jun 12 '18 at 17:57
  • Presumably fan-id.ru – mattdm Jun 12 '18 at 17:58
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    I'm voting to close this question as off-topic because the algorithm that distinguishes between edited and non-edited photos has no relevance to still photography as such. – flolilolilo Jun 12 '18 at 18:08
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    & what would class as 'edited'? 2 different jpg saves from the same RAW would be 'edited' but I doubt anything could determine which was the 'real' one. – Tetsujin Jun 12 '18 at 18:15
  • @Tetsujin Also, a simple crop (or rotation) basically is editing, yet I wouldn't count it as such. That makes an algorithm for "edited" images even more ridiculous. – flolilolilo Jun 12 '18 at 21:53