基于公钥和脆弱水印的图像认证算法

An Image Authentication Scheme Based on Public Key and Fragile Watermarking

本文提出一种基于公钥和小波域脆弱水印的图像完整性认证的算法。该算法不但能够检测和定位窜改,而且能同时验证图像的所有权。该水印方案为盲水印,检测过程不需要原始图像和附加信息。由于该认证算法建立在密码学方法的基础上,因此它是单向、不可逆的,未授权者很难伪造或修改原有的水印。文中分析了针对逐块独立的一类水印算法的"矢量量化攻击",提出了认证链等对抗措施。理论分析和实验结果表明,本文算法具有较好的性质和较高的安全性。

In this paper, we propose an image authentication scheme based on public key and fragile watermarking in wavelet domain for ownership verification and authentication on integrity of image. The scheme is not only able to detect minus modification made to the image and meanwhile indicate the specific location that have been modified, but also can check for the owner of the image according to the user key used in the verification process. The scheme is a blind watermark, and the original image or any other information is not necessary in the process of verification. Since the algorithm is based on the security of the cryptographic function,and requires a user key during both the insertion and the extraction procedures ,it is not possible for an unauthorized user to forge a watermark or alter the existing watermark so that the resulting will pass the test.