EURASIP Journal on Information Security 
Volume 2007 (2007), Article ID 43034, 7 pages
doi:10.1155/2007/43034
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 13902, NY, USA

Received 7 May 2007; Accepted 22 October 2007

Recommended by A. Piva

Abstract

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.