一种基于边信息的数字水印算法

借鉴边信息通信模型的思路,本文提出了一种小波域的数字水印的嵌入和提取算法,且提取时无需原始图像。该方法对原始图像小波变换后的系数,根据其对人类视觉影响的特性,选择出可嵌入信息的系数位置,并以边信息的方式记录下来,然后采取类似扩频的思想进行水印信息的嵌入。算法中为增强安全性,还对系数进行了随机抽取。实验结果表明该算法具有强不可察觉性、高容量性和抗击常见方法干扰的顽健性。

A digital watermark algorithm based on side-information

Based on communication model with side information, a wavelet domain watermarking embedding and extracting algorithm is proposed in this paper, which does not need original image when extracting watermark from watermarked image. The embedding places are located and recorded by side information according the statistical characteristics of wavelet coefficients and visual characteristics of human vision, then the principle of spread spectrum communications is used to embed watermark bits. In order to improve safety, low-frequency coefficients are selected pseudo-random. It has been proved by experiments that this approach is high imperceptibility, large volume, and robustness against attacks such as compression, histogram transformation, smoothing, sharpening, scaling etc.