[judge2020]

> What do you think they were going to do once the scanning turned up a hit? Access the photos? Well that negates the first statement.

In the whitepaper, the cryptography required that Apple have multiple different photodna (or whatever the name was for the on-device one) matches before they could unwrap the user's message containing these suspected CSAM photos and to then send them to NCMEC.

[barsonme]

Also, IIRC, it wasn’t the raw photos. It was small thumbnails of them.

[theshrike79]

"reduced-quality copy" was the wording in the whitepaper IIRC.

So the resolution most likely would've been the same, but the detail blurred so that the poor human agent wouldn't have to see actual CSAM, just enough to make a call whether it is or isn't a likely match.

[FabHK]

It was called a “visual derivative”.

https://www.apple.com/child-safety/pdf/CSAM_Detection_Techni...