This question got me thinking about another project I've got on my 'to do' list. It's a 'multimedia' (blarg) piece with dynamically-generated video projection. I've run an early version of it, but I'd like the video to be partially generated by files on the performer's computer— the idea being that it's going to find your NSFW pics and show them (in mangled, blurred, BGRA-shifted form) buried within the piece. Blah blah, art, edgy, whatever.
Can anyone think of attributes those files would have that, say, vacation snapshots wouldn't? So far it's just image size: super-small images are probably internal support for applications, clip-art or icons. Super-big images probably came straight off a camera. (although maybe not!) But I think there's a way to get smarter than this-- I guess I'm thinking batches of files with non-identical but within-a-short-span creation dates (indicating download) and a "last opened" later than "last modified".
Surely there are some others, or reasons why the ones I list wouldn't work?
This will be a C++ binary but can call a shell script if that's a better way of doing what I need.