[quasiresearcher]

But those algorithms would be very limited in usefulness. Systems such as imageidentify.com should be at least trying an ensemble of algorithms, many of which I suppose should be invariant under translation and rotation.

Edit: There's a comment about invariance in this thread [1] and apparently CNNs are not invariant under rotation.

[1] https://news.ycombinator.com/item?id=9750133