摘要
通过对多种空域水印算法优缺点的分析,提出了一种新的图像空域盲水印算法。利用广义猫映射将各水印比特的嵌入位置随机置乱到整个载体图像的像素空间;再用Logistic混沌映射随机产生各水印比特嵌入载体像素的比特位置;各水印比特被随机嵌入到像素点的某一中间比特位,并采用最小化像素改变量的优化策略;提取水印只需要密钥,且密钥空间大。实验结果表明:嵌入水印隐蔽性好,同时具有很强的抵抗剪切攻击、LSB(最不重要比特位)攻击、多低位破坏攻击和椒盐噪声攻击的鲁棒性;合法用户能方便快捷地提取水印,而非法用户则不能提取正确水印。因此,这种基于双混沌映射的水印算法,不仅使嵌入水印具有良好的隐蔽性、鲁棒性和安全性,而且使算法具有很好的现实可操作性。
Through the analysis of many representative spatial domain watermarking algorithm, a novel image spatial domain blind watermarking algorithm was presented. The proposed scheme (utilized) general cat map to scramble watermark embedding positions randomly throughout the whole pixels space of image. Then Logistic chaotic map is utilized to generate watermarks embedding bit positions in the host image pixels. All the watermarking bits are embedded in one of the middle bits of host image pixels. And the strategy of minimizing changes of host image pixels is adopted. To extract watermark, only security keys are required, and the space of security keys is very large. The experimental results show that the difference between the watermarked and original image is perceptually invisible, and the watermark is robust against cut attack, LSB(least significant bit) attack, many of low bits damage attack and salt-pepper noise attack. It is convenient for the owner of keys to extract watermark and impossible for the unaccredited to do so. Therefore, the embedded watermarks with this double chaotic map based watermarking algorithm are not only invisible, robust and safe, but the algorithm is also very exercisable.
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2005年第2期272-276,共5页
Journal of Central South University:Science and Technology
基金
教育部博士点基金资助项目(20040533036)
湖南省自然科学基金资助项目(03JJY4054)
关键词
混沌映射
信息隐藏
空域水印
chaotic map
information hiding
spatial domain watermarking
