Earlier quoted context omitted.
Yes it does, it uses fuzzy perceptual hashes not crypto hashes. So if your innocent baby pic looks similar enough to a previously tagged child abuse image then YES, it will flag you and send a copy to the feds. And before you correct me, the Apple employee will see a picture of your naked baby and hit “forward to NCMEC”, which… upon investigation is actually just the feds
Perceptual hashes are extremly accurate. You might need a twin and top of that somehow identical environment almost in pixel level. Are news filled with false-positive accusations by PhotoDNA, flagging wrong images in Google, Facebook, Instagram etc.?
No, they are not. Ask anyone who has worked in this space[1][2], including myself. They are incredibly common.
Two images that kind of look like one another will have similar or the same hashes. That is the point of perceptual hashing.