Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Reverse-Engineering a Watermark Detector Using an Oracle | Hindawi Publishing Corporation EURASIP Journal on Information Security Volume 2007 Article ID 43034 7 pages doi 2007 43034 Research Article Reverse-Engineering a Watermark Detector Using an Oracle Scott Craver Idris Atakli and Jun Yu Department of Electrical and Computer Engineering Binghamton University Binghamton NY 13902 USA Correspondence should be addressed to Jun Yu jyu7@ Received 7 May 2007 Accepted 22 October 2007 Recommended by A. Piva The Break Our Watermarking System BOWS contest gave researchers three months to defeat an unknown watermark given three marked images and online access to a watermark detector. The authors participated in the first phase of the contest defeating the mark while retaining the highest average quality among attacked images. The techniques developed in this contest led to general methods for reverse-engineering a watermark algorithm via experimental images fed to its detector. The techniques exploit the tendency of watermark algorithms to admit characteristic false positives which can be used to identify an algorithm or estimate certain parameters. Copyright 2007 Scott Craver et al. This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited. 1. INTRODUCTION The Break Our Watermarking System BOWS contest gave researchers a unique opportunity to test existing techniques for breaking a watermarking algorithm 1 . The contest also posed the researcher with a separate problem given an unknown watermark detector can one deduce the underlying algorithm from its output This can also be attacked using adaptive inputs to a detector except in this case the inputs are not used to find a better image but to leak information about a detector structure s components. We used this approach to reverse-engineer the BOWS watermark by posing carefully designed images to the .
