Creating good CAPTCHAs is harder than one might think (see Defeating CAPTCHAs under External links at end of the article). One example is a research group at UC Berkeley Computer Vision Group claim that their Shape Contexts based approach has a 92% success rate in solving Yahoo's gimpy CAPTCHA.

Of course, it all depends on what is considered to be secure enough for the given application in question.

--
Andreas

In reply to Re^2: Perl Captcha Solution by andreas1234567
in thread Perl Captcha Solution by Anonymous Monk

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