基于多尺度小波分解的自适应图象水印算法  

A Level-Adaptive Digital Watermarking Algorithm Base d on the Wavelet Transform

作　　者：强英[1] 王颖[1] 

机构地区：[1]中国科学技术大学研究生院,北京100039

出　　处：《计算机工程与应用》2004年第7期42-45,共4页Computer Engineering and Applications

基　　金：国家863高技术研究发展计划项目(编号:2003AA144081)

摘　　要：该文提出了一种多尺度小波域的自适应水印算法,水印采用有意义二值图。自适应地确定嵌入系数的阈值,根据0/1水印值对3级小波系数,由高尺度层向低尺度层,有选择地进行细节图象系数的量化。恢复不需原图,只需相关参考序列,恢复水印亦是二值图,效果直观。经攻击实验证明,对图象噪声、剪切和压缩具有一定的鲁棒性,是一种可行的水印算法。This paper presents an approach for still image watermarking which is based on multiresolution wavelet decomposition.The watermark is2-bit image.People adaptively set the coefficients of each detail subband,select significant coefficients and quantize them from high scale level to low scale level.It need s no an original image but reference sequence to extract the watermark.The extracted watermark is also2-bit image and it's visually effective.Through the attack experiments,the algorithm is robust against the attacks of noise,crop and compression.

关 键 词：数字水印 小波变换 尺度 量化 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]