【摘要】 目前,大多数鲁棒图像水印所面临的最大问题就是几何攻击,而现有水印技术大都难以抵抗几何变换类攻击,如旋转、尺度变换等,由于几何攻击破坏了水印分量的同步,即使微小幅度的图像旋转或尺度变换都可能导致水印检测过程失败。提出了一种新颖的基于傅立叶变换的方法来估计图像经历的几何变换。实验证明,提出的方案对几何变换攻击的水印同步具有很高的精确度。更多还原

【Abstract】 Geometric attacks are the challenging problems that most robust image watermarking systems face today.And most present watermarking technology is difficult to resist geometrical attacks such as rotation and scaling.Even the most slight rotation and scaling will lead to the failing of watermark detecting because the geometric attacks destroy the synchronization of watermarks.In this paper we report a novel method to estimate geometrical attacks the image has undergone based on Fourier Transformation.Experiments indicate that the scheme proposed in this paper has high precision of geometrically attacked watermark’s synchronization.更多还原