This paper describes two distortion estimation techniques for object recognition that solve EZ-Gimpy and Gimpy-r, two of the visual CAPTCHAs ("completely automated public turing test to tell computers and humans apart") with high degrees of success. A CAPTCHA is a program that generates and grades tests that most humans can pass but current computer programs cannot pass. We have developed a correlation algorithm that correctly identifies the word in an EZ-Gimpy challenge image 99% of the time and a direct distortion estimation algorithm that correctly identifies the four letters in a Gimpy-r challenge image 78% of the time.


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    Title :

    Distortion estimation techniques in solving visual CAPTCHAs


    Contributors:
    Moy, G. (author) / Jones, N. (author) / Harkless, C. (author) / Potter, R. (author)


    Publication date :

    2004-01-01


    Size :

    561200 byte





    Type of media :

    Conference paper


    Type of material :

    Electronic Resource


    Language :

    English



    Distortion Estimation Techniques in Solving Visual CAPTCHAs

    Moy, G. / Jones, N. / Harkless, C. et al. | British Library Conference Proceedings | 2004





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