Abstract: The algorithm resilient geometric distortion is an important research direction in copyright protection. This paper proposes an image watermark algorithm based on discrete Fourier transform (DFT) and singular value decomposition (SVD) because of the good property of DFT amplitude matrix and the characteristic of SVD that it is stabilization to geometric distortion such as rotation, scale and translation. Experimental results show that the algorithm has more embedding capacity and robust to common attacks and geometric distortion.

Key words: Watermark, Discrete Fourier transform (DFT), Singular value decomposition (SVD), Geometric distortion

摘要： 抗几何攻击水印算法是版权保护领域的一个重要的研究方向。根据离散傅立叶变换幅度谱矩阵的性质，以及矩阵奇异值分解对旋转、缩放和平移等几何攻击具有稳定性的特点，提出了一种基于离散傅立叶变换和奇异值分解的抗几何攻击图像水印算法。实验结果表明该算法有较大的嵌入容量，对常规攻击和几何攻击都具有较强的鲁棒性。

关键词: 水印, 离散傅立叶变换, 奇异值分解, 几何攻击