基于混沌的DCT域图像水印算法  

Digital watermarking Scheme based on chaotic encryption and DCT

作　　者：殷柯[1,2] 刘光杰[2] 王执铨[2] 

机构地区：[1]南京理工大学自动化学院,南京210094 [2]南京工程学院电力仿真与控制工程中心,南京211167

出　　处：《微计算机信息》2010年第29期23-24,29,共3页Control & Automation

基　　金：基金申请人:刘光杰;项目名称:图像感知哈希理论及方法研究;基金颁发部门:江苏省博士后基金课题(0801044B)

摘　　要：提出了一种基于混沌序列和RSA公钥密码体制的二值水印图像加密方案,利用混沌序列的随机性打乱水印图像像素值和位置,再运用RSA公钥加密算法对置乱后的水印图像进行二次加密。经过RSA二次加密变换后成为一幅新的"平滑"图像,其高频成分和低频成分都变成了中低频成分。结合小波变换和离散余弦变换的特点,将该"平滑"的水印图像嵌入到载体图像的中低频成分中,很好地解决了水印不可见性与鲁棒性之间的矛盾。仿真结果表明,利用该方法使嵌入的二值水印图像具有较强的鲁棒性,能够抵抗各种噪声、滤波、压缩和几何变换等攻击。By introducing chaotic sequence and RSA public key cryptography,a novel binary image watermark algorithm is presented.The pixel positions as well as pixel values of original watermark image are confused by employing chaotic sequence.This scrambledimage then passed through RSA algorithm to be encrypted.The final watermarked image is smooth and its low and high-frequencycomponents become the middle and low-frequency components.With wavelet transform and discrete cosine transform,this smooth image is embedded in the middle and low-frequency components of the carrier image,which solve the contradiction between robustnessand imperceptibility.The simulation results show that this watermarking algorithm has strong invisibility and has robustness to different kinds of watermarking attacks such as noise,compression,cropping and geometric transformations etc.

关 键 词：图像水印 混沌映射 RSA公钥加密 离散余弦变换 

分 类 号：TP391[自动化与计算机技术—计算机应用技术] TP309.2[自动化与计算机技术—计算机科学与技术]