IMAGINATION: A Robust Image-based CAPTCHA
Ritendra Datta, Jia Li, James Z. Wang
The Pennsylvania State University, University Park, PA 16802
We propose IMAGINATION (IMAge Generation for
INternet AuthenticaTION), a system for the generation of
attack-resistant, user-friendly, image-based CAPTCHAs. In
our system, we produce controlled distortions on randomly
chosen images and present them to the user for annotation
from a given list of words. The distortions are performed
in a way that satisfies the incongruous requirements of low
perceptual degradation and high resistance to attack by
content-based image retrieval systems. Word choices are
carefully generated to avoid ambiguity as well as to avoid
attacks based on the choices themselves. Preliminary results
demonstrate the attack-resistance and user-friendliness of
our system compared to text-based CAPTCHAs.
Full Paper in Color
Ritendra Datta, Jia Li and James Z. Wang, ``IMAGINATION: A Robust
Image-based CAPTCHA Generation System,'' Proceedings of the ACM
Multimedia Conference, pp. 331-334, Singapore, ACM, November 2005.
Copyright 2005 ACM.
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Wed Nov 2 11:38:12 EST 2005