Ideally you'd run something like thispersondoesnotexist to generate random faces to paste overtop people before blurring it. That way if you somehow manage to r

Ideally you'd run something like thispersondoesnotexist to generate random faces to paste overtop people before blurring it. That way if you somehow manage to revert the blur there's still no chance of revealing the original person. Of course humans are pretty good at filling in detail, so with a sufficient blur you can get away with surprisingly poor approximations of a human face.