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Building a Better CAPTCHA

Posted by Soulskill on from the we-have-the-technology dept.

jcatcw writes "Steven J. Vaughan-Nichols reports that CAPTCHA cracking isn't that difficult these days. It has even become a business. For example, DeCaptcher.com will solve CAPTCHAs for your spamming needs at a rate of $2 per 1,000 successfully cracked CAPTCHAs. In response, newer systems are in development. Both Carnegie Mellon and Penn State (is there something about the water in PA?) are working on image-based systems. ESP-PIX and SQ-PIX both require the viewer to interpret pictures. Imagination CAPTCHA from Penn has the user find the center of an image. The idea is that humans are better at image recognition that computers, but humans can legitimately disagree on their interpretations and some humans are color blind. Problems remain. For now, sites would be well advised to look at reCAPTCHA — the system that works with Google Books and the Internet Archive to digitize printed texts — which comes with a wide variety of application and programming plug-ins and an open API."

2 of 197 comments (clear)

  1. Indecipherable by Bordgious · · Score: 5, Insightful

    I know _I_ often have trouble seeing those... Maybe some sort of an animated .gif would be better?

  2. Dying Technology by EdIII · · Score: 5, Insightful

    The idea is that humans are better at image recognition that computers

    C.A.P.T.C.H.A - Completely Automated Public Turing test to tell Computers and Humans Apart.

    This is a dying technology.

    1) Computers and synthetic systems in general are ONLY going to get better at doing anything a human can do. I mean anything.

    2) Humans are a substitute for our lack of a synthetic system to solve a CAPTCHA.

    A CAPTCHA has two answers to it's owner. This is a Human and this is a Computer. Humans can be hired to solve CAPTCHA at economically viable rates to meet the demand with a supply. Computers are catching up at being able to solve various CAPTCHAs creating an "arms race" between developers and those that need to crack CAPTCHA automatically with high throughput.

    The window for this technology to be effective in its use is shrinking rapidly and it will only be a matter of time before it is nearly impossible to tell without phsyical inspection what is a synthetic human reponse and an actual one.