关键词: 奇异值分解, 图像水印, 伪验证

Abstract: A fatal bug of a kind of Singular Value Decomposition (SVD)-based image watermarking was discovered in this paper. That is, using the same secret key which is produced in the embedding procedure, highly correlative watermark information can be extracted from other different images, even including non-watermarked images. This newly discovered bug was named as fake verification of watermark algorithm. At the same time, the definition and judging condition of fake verification were also presented. Then, the experimental results reveal that the watermark information is involved in the orthogonal matrix U,V after SVD. And the extracted watermark information is mainly involved in U,V, and the distribution of single value instead of exact single value. That is the reason why the SVD-based watermark algorithm has the bug of fake verification.

Key words: Single Value Decomposition (SVD), image watermarking, fake verification