基于JPEG2000的半脆弱水印算法研究

提出了一种基于JPEG2000图像压缩标准的半脆弱水印的算法.该算法直接从原始图像中提取特征,经过编码作为数字水印嵌入到该图像中去,而不增加其他额外的信息.为了提高算法的安全性,引入了个人私钥对水印信号进行加密.试验结果显示,在图像没有受到任何改变的情况下,可以顺利的通过此认证系统;即使图像经过了一些常用的图像处理如JPEG压缩等,仍然可以通过认证;而当图像受到恶意的攻击后,则检测不到水印信号,被恶意攻击的部分可以被认证系统检测出来.

A Semi-fragile and Weak Watermark Algorithm Based on JPEG 2000

A semi-fragile and weak watermark algorithm is proposed based on JPEG 2000 image compression standard.In the algorithm the character is directly extracted from original image,and encoding as a digital watermark is embedded into the image without adding the other information.For the purpose of improving the safety of algorithm,a personal key is used to encrypt the watermark signals.Test result shows that under the condition of unchanged image,the image can pass the authentification system smoothly,though JPEG compression is made for the image,it can also pass the authentification,when the image is viciously attacked,the watermark signal can not be checked,the attacked part can still be detected by the authentification system.