一种抗几何攻击的数字图像零水印算法

摘要

In order to improve the zero-watermarking method against geometric attack ability,this paper proposes a zero-watermarking algorithm based on edge detection and log-polar mapping（LPM）.First,using the SUSAN edge detector to extract the important edge information of image,then making use of LPM to process the edge graph,and using scrambling watermark to get the secret figure.When extracting watermarking,it only needs secret figure and scrambling watermark,without the original image.The experiment results demonstrate the proposed method is robust enough to various geometric attacks such as rotation,cropping,scaling,meanwhile,it is also robust enough to adding noise,filtering and JPEG compression.%为加强零水印抗几何攻击的能力,该文提出一种边缘检测与对数极坐标映射相结合的零水印算法。首先利用SUSAN边缘检测法获取图像的重要边缘信息,然后将边缘图进行对数极坐标映射,再与置乱水印异或获取密图。提取水印时只需密图和置乱密钥,无需原始图像。实验结果表明该算法对于旋转、剪贴、缩放等各类几何攻击具有较好的鲁棒性,同时对于加噪、滤波以及JPEG压缩等攻击也具有良好的鲁棒性。