一种基于公钥认证可恢复的半脆弱水印算法  

A Resumable Semi-fragile Watermarking Algorithm based on Public-Key Authentication

作　　者：薛锋[1] 汪定[1] 王立萍[1] 

机构地区：[1]解放军汽车管理学院训练部,安徽蚌埠233011

出　　处：《计算机安全》2011年第4期25-28,共4页Network & Computer Security

摘　　要：给出了一种基于公钥认证可恢复的半脆弱性水印新算法:首先对原始图像进行信息提取,得到水印图像;然后对原始图像和水印图像分块,并将经公钥加密后的各原始图像块的Hash值填充到相应水印图像块的最低位;接着对水印块进行置乱和嵌入。在图像检测时,能够对图像的篡改区域进行精确的检测与定位,并有效恢复出篡改区域图像。实验结果表明了算法的可行性与有效性。A resumable semi-fragile watermarking algorithm based on public-key authentication was proposed.Firstly,each pixel of the original image was extracted,then the extracted image comes to be the watermarking image.In the following,the original image and the watermarking image was blocked,and the public-key encrypted Hash value of each block of the original image is put into the lowest bit of the corresponding pixel of the corresponding watermarking image block.After the watermarking image blocks were scrambled,the watermarking was embedded by replacing the lowest two bits of each corresponding-position pixel of the original image.When coming to the authentication,we can detect and indicate the exact position of tampered part of image according to the previously saved Hash value and the image can be roughly rebuilt based on the previously saved message.Experiment results show the feasibility and efficiency of this algorithm.

关 键 词：半脆弱水印 公钥认证 HASH函数 恢复 

分 类 号：TP391.4[自动化与计算机技术—计算机应用技术]