基于小波系数块相似鲁棒育水印水印技术  

Robust Public Watermarking Technique in Wavelet Domain Based on Wavelet Factor

作　　者：刘泽平[1] 徐向阳[1] 贺文华[1] 

机构地区：[1]湖南大学计算机与通信学院

出　　处：《科学技术与工程》2008年第15期4142-4147,共6页Science Technology and Engineering

摘　　要：在充分考虑图像相关性的基础上,提出一种基于欧氏距离和DWT域的鲁棒公开水印技术算法。首先对原始图像做三级小波变换,然后将三级小波变换低频系数子带分为N个2×2子块,利用欧几里德距离作为相似性度量,建立最相似环模型,最后根据环中相邻两块的信息熵的大小关系,控制低频子带系数嵌入水印信号的强度,并通过修改块间的相似度,来嵌入水印信息。算法以环模型中块顺序作为密钥无须借助原图像实现对水印的正确提取。实验结果表明,该算法是有效的,较好地解决了水印不可见性与鲁棒性之间的矛盾,对通常的图像处理操作和裁剪、挤压、像素移位等几何攻击有较强的鲁棒性。By taking full advantage of the relativity of image, in Euclidean distance and DWT domain is presented. Firstly, the a robust public watermarking technique operating original image is made 3-level wavelet transform. Then the 3-level wavelet low frequency sub-band is dispersed in N 2 x 2 blocks, and furthest resemble annulus model is built by making use of Euclidean distance as comparability measurement. Finally, according the relation between two contiguous blocks of information entropy in annulus, the intensity of embedding watermark signal is controlled in the low frequency sub-band, and watermark information is embedded by modifying the blocks compa- rability. The algorithm keeps the blocks sequence in annulus model as cryptogrammic key, and realizes valid distil- ling watermark without original image. The experiment results show that the proposed algorithm is effective to the conflict between the invisibility and robust of watermark, and robust to common image processing operations and some geometric distortions such as cropping, pinching, pixel-shift, and so on.

关 键 词：DWT 公开水印技术 环模型 相似性 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]