基于离散切比雪夫变换的数字水印

摘要

着重分析了常见图像置乱算法的基本特征，给出了一种基于Knight，s tour矩阵和Arnold变换对数字图像进行置乱的算法，分析了图像的离散切比雪夫变换，提出了先对水印进行置乱，然后嵌入原始图像数字水印算法，并用MATLAB R2014B对二维灰度图像进行基于离散切比雪夫变换的数字水印仿真。从仿真结果可以看出，文章提出的数字水印算法提取的水印的PSNR值更高。%The essential features of the normal image scrambling are analyzed and a new digital image scrambling approach based on Knight,s tour matrix and Arnold transform is put forward and the discrete tchebichef transform is analyzed. The process includes watermarking scrambling, embedding original image digital watermarking and digital watermarking realization of two-dimensional grey image with MATLAB R2014B on the basis of discrete orthogonal tchebichef transform. Realization results indicate that the approach based on discrete tchebichef transform for digital watermarking can extract digital water-mark with higher PSNR.