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Google Algorithm Busts Captcha With 99.8 Percent Accuracy

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Street View images that can be solved by the algorithm.

While the algorithm used by Google Street View to improve Google Maps can beat CAPTCHAs with 99.8-percent accuracy, Google insists its own CAPTCHA service is effective.

Credit: Google

The algorithm used by Google's Street View team to improve Google Maps also can beat CAPTCHAs (Completely Automated Public Turing test to tell Computers and Humans Apart) with 99.8 percent accuracy.

Google says the algorithm can accurately recognize 90 percent of street numbers in natural or blurry images. Google says reading characters from photographs is a hard problem to solve, but its researchers have overcome the challenge with the use of a "deep convolutional neural network that operates directly on the image pixels."

Nonetheless, Google says its own CAPTCHA service, reCAPTCHA, is effective. Last year, Google added advanced risk analysis techniques that enable the system to consider user engagement before, during, and after interaction with the service. The system uses this analysis to help determine whether a potential user is human or not, before deciding how difficult a puzzle present.

From ZDNet
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Abstracts Copyright © 2014 Information Inc., Bethesda, Maryland, USA


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