基于非抽样Contourlet变换的彩色图像数字水印算法  

An Algorithm for Color Image Digital Watermarking Using the Nonsubsampled Contourlet Transform

作　　者：梁栋[1] 殷兵[1] 于梅[1] 李新华[2] 王年[1] 

机构地区：[1]安徽大学计算智能与信号处理教育部重点实验室,安徽合肥230039 [2]安徽大学电子科学与技术学院,安徽合肥230039

出　　处：《光学学报》2008年第8期1469-1474,共6页Acta Optica Sinica

基　　金：国家自然科学基金(60772121);安徽省自然科学基金(070412065);安徽省高等学校自然科学研究项目(2005KJ005ZD);安徽大学211工程学术创新团队资助课题

摘　　要：研究了小波变换和Contourlet变换的不足,利用非抽样Contourlet变换的多尺度性、多方向性以及平移不变性特征进行彩色图像数字水印。先对图像进行非抽样Contourlet变换得到不同尺度不同方向上的系数,然后为了满足水印的不可见性和稳健性,在低频系数和高频系数中采用不同的嵌入强度,并依据人类视觉的彩色感知特性,在蓝色分量中嵌入较多水印,在其他颜色分量选取变换系数能量最大的区域嵌入水印。与同样嵌入规则的Contourlet变换算法和平稳小波变换算法相比,该算法具有更好的稳健性,利用该算法得到的水印相似度更高,最高可提高约0.5。The disadvantages of wavelet transform and contourlet transform are studied. Color image digital watermarking is implemented based on the multi-scale, multi-direction, and shift-invariance of the nonsubsampled transform. The coefficients in different scales and directions are obtained by image decomposition using the nonsubsampled contourlet transform. Embedding intensities of the low and high frequency coefficients are different invisibility and robustness of watermark requirements for according to the color perception characteristics of human visual system, watermark embedded in blue channel is more than the others, which only choose the local of maximal energy to embed. Compared with the algorithms of stationary wavelet transform and contourlet transform under the same embedding rule, this algorithm is more robust, with higher similarity which can be improved by O. 5 at most.

关 键 词：信息安全 数字水印 非抽样CONTOURLET变换 彩色图像 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]