Image Recognition CAPTCHAs

نویسندگان

  • Monica Chew
  • J. Doug Tygar
چکیده

CAPTCHAs are tests that distinguish humans from software robots in an online environment [3, 14, 7]. We propose and implement three CAPTCHAs based on naming images, distinguishing images, and identifying an anomalous image out of a set. Novel contributions include proposals for two new CAPTCHAs, the first user study on image recognition CAPTCHAs, and a new metric for evaluating CAPTCHAs.

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تاریخ انتشار 2004