一种基于DWT的双密钥盲水印设计方案

为了更好地保护互联网上的数字图像的版权,给出了一种基于小波变换域的数字水印设计方案,水印信息是代表作品和作者特征的二值图像,实现了水印的盲提取。针对不断出现的各种各样的水印攻击,尤其是解释攻击。通过对攻击原理的分析,提出了由认证中心分密钥和作者分密钥组成的双密钥水印嵌入与提取方案,较好地解决了水印在抗解释攻击方面存在的问题,提高了水印信息的安全性。实验结果表明:该方案不仅具有良好的不可见性,而且对JPEG压缩、高斯噪声、图像剪切和中值滤波等攻击有理想的鲁棒性。如何有效地提取作品特征值以及解决水印嵌入强度与图像降质之间的矛盾,将是本课题进一步要研究的方向。

A Design Scheme for Blind Watermark of Double Keys Based on DWT

An digital watermark scheme based on DWT is proposed to protect the copyright of internet digital image.This digital watermark is a binary image with feature of works and the author,and doesn't need the original image when extracting the watermark data.Due to more and more attacks on it,especially interpretation attack,in this paper,a kind of embedding and recovery method of watermark is presented after analysing the principle of attack.It includes two keys from attestation centre and author.This method can solve the interpretation attack and improve the watermark security.The experiment results show that the embedded digital watermark by the scheme is invisible and robust enough to watermark attack,such as JPEG compression,noise,image cropping and median filter.How to extract the characteristic value effectively and how to solve the problem of embedding strength and image degradation will be the directions for future research.