CAPTCHAs. In the absence of a Voigt-Kampff apparatus, they're what separate the humans from the only-posing-to-be-human. And now three Stanford researchers have further blurred that line with Decaptcha, a program that uses image processing, anti-segmentation and a spell-checker to defeat text-based CAPTCHAs. Elie Bursztien, Matthieu Martin and John Mitchell pitted Decaptcha against a number of sites: it passed 66% of the challenges on Visa's Authorize.net and 70% at Blizzard Entertainment. At the high end, the program beat 93% of MegaUpload's tests; at other end, it only bested 2% of those
