IMAGINATION: a robust image-based CAPTCHA generation system

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. Categories and Subject Descriptors K.6.5 [Management of Computing and Information Systems]: Security and Protection. General Terms Verification, Security. Keywords Automated Turing test, CAPTCHA, image retrieval.

• Type: Conference
• Year: 2005
• Where: MM
• Authors: Ritendra Datta, Jia Li, James Ze Wang
• Keywords: Content-based Image Retrieval, Image Retrieval, Image-based Captchas, MM 2005