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Re: Visual Captchas AKA Word Verification Systems


From: Valdis.Kletnieks () vt edu
Date: Sun, 13 Jun 2004 20:44:44 -0400

On Sun, 13 Jun 2004 18:27:22 -0000, Tom K <keetch_tw () hotmail com>  said:

Secondly, would it be possible if anyone could kindly supply me with a few 
links to practical information on Optical Character Recognition, since I am 
still trying to improve my character recognition rate which is currently at 
20-50% depending on the obfuscations applied. i.e. Grids, lines and fuzzing 
are easily removed, skewing is less so.

If you want close to 100%, just take the image you get passed, and drop it
as the "secret leet key" to get access to a free porn site, and let the users
decrypt it for you.  This is currently reported as a technique in active use
by spammers to work around those captchas.....

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