基于DC和AC分量的二维数字水印算法  

A Watermark of Two Dimensions Based on DC and AC Components

作　　者：余燕忠[1] 王新伟[2] 刘建华[3] 

机构地区：[1]福建泉州师范学院物理系,福建泉州362000 [2]华东师范大学计算机科学系,上海200062 [3]桂林航天工业高等专科学校计算机系,广西桂林541004

出　　处：《微机发展》2003年第4期49-52,共4页Microcomputer Development

基　　金：国家973项目资助(G19980304192-2)

摘　　要：提出一种新的二维数字水印算法,该算法先把原始图像分块DCT,再对水印图像分块DCT,取每一图像块的直流系数和前12个DCT低频交流系数,分别构成水印信号的直流分量和交流分量。利用能量比确定各个子块的直流拉伸因子和交流拉伸因子。水印信号的直、交流分量以不同的能量分别嵌入到原始图像块DCT域的DC分量和AC分量中。实验结果表明,该算法具有良好的不可见性和稳健性。A new algorithm of two dimensions watermark is proposed in this paper. The algorithm splits the original image into some blocks and transformed them by DCT. The watermark image is dealt with same process. DC components and AC components of watermark are composed of DC coefficients and twelve low-frequency AC coefficients of every watermark image block respectively. Applying energy ratio, the scaling parameters of DC and AC are calculated for every original image block. DC components and AC components of watermark with different strength are embedded into DC components and low-frequency AC components of original image blocks in DCT. Experimental results show that the proposed algorithm has good imperceptibility and robustness. 

关 键 词：二维数字水印算法 DC分量 AC分量 信号处理 图像分块 图像处理 空域技术 

分 类 号：TN911.73[电子电信—通信与信息系统] TP391.41[电子电信—信息与通信工程]