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 Anonymous Fingerprinting with Robust QIM Watermarking Techniques | Hindawi Publishing Corporation EURASIP Journal on Information Security Volume 2007 Article ID 31340 13 pages doi 2007 31340 Research Article Anonymous Fingerprinting with Robust QIM Watermarking Techniques J. P Prins Z. Erkin and R. L. Lagendijk Information and Communication Theory Group Faculty of Electrical Engineering Mathematics and Computer Science Delft University of Technology 2628 Delft The Netherlands Correspondence should be addressed to Z. Erkin Received 20 March 2007 Revised 4 July 2007 Accepted 8 October 2007 Recommended by A. Piva Fingerprinting is an essential tool to shun legal buyers of digital content from illegal redistribution. In fingerprinting schemes the merchant embeds the buyer s identity as a watermark into the content so that the merchant can retrieve the buyer s identity when he encounters a redistributed copy. To prevent the merchant from dishonestly embedding the buyer s identity multiple times it is essential for the fingerprinting scheme to be anonymous. Kuribayashi and Tanaka 2005 proposed an anonymous fingerprinting scheme based on a homomorphic additive encryption scheme which uses basic quantization index modulation QIM for embedding. In order for this scheme to provide sufficient security to the merchant the buyer must be unable to remove the fingerprint without significantly degrading the purchased digital content. Unfortunately QIM watermarks can be removed by simple attacks like amplitude scaling. Furthermore the embedding positions can be retrieved by a single buyer allowing for a locally targeted attack. In this paper we use robust watermarking techniques within the anonymous fingerprinting approach proposed by Kuribayashi and Tanaka. We show that the properties of an additive homomorphic cryptosystem allow for creating anonymous fingerprinting schemes based on distortion compensated QIM DC-QIM and rational dither modulation RDM improving the robustness of the embedded fingerprints. We evaluate .
