Comments for The Cutest Human-Test: KittenAuth

In effect, this is a 3 letter password, using an alphabet consisting of perhaps several hundred letters. While a PC might have a hard time identifying an image as say, kitten vs puppy, consider that the spammer can identify these pictures themself much faster than you can make these pictures. (Then again, maybe with panning zooming video cameras and using every frame of high fps video as a picture...)

While the filename might be random, unless (and probably even it) you use literally gigs of pictures spammers can just store them, organized by an index calculated from the 1st 2-300 bytes. This would give fast recall for matching and with software designed for image comparison, if a newly introduced frame was similar enough to a previous, perhaps cause a match without the exact picture already stored. With proper techniques (condensing pictures, averaging every 4 pixels into a single pixel to make a 1/4 size image, or greatly magnifying this the people breaking the system could really cut down on their space requirements. You don't want to cut down on file size in that the larger the size the more time consuming it is to match images.

Kitten discovery could also be made easier by above-mentioned image matching software, grouping pictures for similarity, perhaps 100 to a page with a human 1st choosing "overall kitten" or "overall not a kitten" and then clicking exceptions.

On the other hand... this could lead to the creation of powerful image recognition software, which were the spammers to offer, might make for a legitimate product for them. So, what else would be good challenge, currently seen as "impossible" that a little greed-driven R&D might help out?