Eighth International Conference on Document Analysis and Recognition (ICDAR'05) ScatterType: A Legible but Hard-to-Segment CAPTCHA Seoul, Korea August 31-September 01 ISBN: 0-7695-2420-6
The ScatterType CAPTCHA, designed to resist character? segmentation attacks and shown to be highly legible to human readers, is analyzed for vulnerabilities and is offered for experiments in automatic attack. As introduced in [BR05], ?ScatterType? challenges are images of machine-print text whose characters are cut into pieces which then drift apart, in an attempt to frustrate segment-then-recognize computer vision attacks. Analysis of experimental human legibility data has shown that better than 95% correct legibility can be achieved through judicious choice of the pseudorandom generating parameters [BMW05]. That analysis is summarized and discussed here as motivation for a discussion of potential vulnerabilities. An invitation to attack ScatterType is offered.
Index Terms:
CAPTCHAs, human interactive proofs, document image analysis, abuse of web sites and services, human/machine discrimination, Turing tests, legibility of text, segmentation, fragmentation, Gestalt perception, automatic attacks on CAPTCHAs
Citation:
Henry S. Baird, Michael A. Moll, Sui-Yu Wang, "ScatterType: A Legible but Hard-to-Segment CAPTCHA," icdar, pp.935-939, Eighth International Conference on Document Analysis and Recognition (ICDAR'05), 2005 Usage of this product signifies your acceptance of the Terms of Use. | |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||