As a test, I ran this on a very early backup of lemm.ee images from when we had very little federation and very little uploads, and unfortunately it is finding a whole bunch of false positives. Just some examples it flagged as CSAM:

• Calvin and Hobbes comic
• The default Lemmy logo
• Some random user’s avatar, which is just a digital drawing of a person’s face
• a Pikachu image

Do you think the parameters of the script should be tuned? I’m happy to test it further on my backup, as I am reasonably certain that it doesn’t contain any actual CSAM

Any thoughts about using this as a middleware between nginx and Lemmy for all image uploads?

Edit: I guess that wouldn’t work for external images - unless it also ran for all outgoing requests from pict-rs… I think the easiest way to integrate this with pict-rs would be through some upstream changes that would allow pict-rs itself to call this code on every image.