图像插值空间大容量可逆数字水印算法  

High capacity reversible watermarking for image interpolation space

作　　者：王继军[1] 

机构地区：[1]广西财经学院信息与统计学院,南宁530003

出　　处：《中国图象图形学报》2014年第4期527-533,共7页Journal of Image and Graphics

基　　金：国家自然科学基金项目(61262002);广西自然科学基金项目(2013GXNSFBA019274);广西财经学院科研项目(2013B050);国家哲学社会科学基金重大项目(12&ZD041)

摘　　要：目的可逆数字水印技术在遥感、医学、军事等众多领域有着广泛应用,而现有大数可逆水印算法需要依赖于附加信息,严重影响了嵌入容量,为此提出一种无附加信息的大容量可逆水印算法。方法首先设计了一种类似双线性插值原理的图像放大方法,并利用该方法将载体图像放大为原来的4倍,放大图中有1/4的插值点保留了原始图像信息,其余插值点均可嵌入水印。为了在插值的同时同步嵌入水印,先利用随机函数选取水印嵌入位置,再由嵌入水印信息决定理论插值的最终取值,实现水印嵌入。结果该方法保证了水印的均匀分布,而且最大限度地降低了嵌入水印对插值的影响,同时还提高了算法效率和水印安全性。与经典插值算法相比,生成的含水印图像质量较好,且对任何载体图像嵌入率均能达到0.75 bit/pixel。结论大量实验结果表明,算法隐蔽性好、安全性高、嵌人率高、实用性强。Objective Reversible digital watermarking technology has been widely applied in many fields. Concerning most of the existing reversible watermarking algorithms need a lot of additional information; this paper presents a high capacity reversible watermarking algorithm, which does not need any additional information. This algorithm depends on the image in- terpolation space. Method First, we design a similar bilinear interpolation image amplification method, and enlarge the cover image by four times its original size. 1/4 pixels of the magnification image retain the original image information, and the other pixels can be embed the watermarking. During the interpolation process. We use a random function to select water- mark-embedding position first and then determine the rounding mode and achieve watermark embedding by the watermarking information and the theoretical value. Result This method ensures a uniform distribution of the watermarking and it also min- imizes the effect of the interpolation, while improving the security. Compared with the classical interpolation algorithms, the last image is better, and embedding rate can reach around 0. 75 bit/pixel. Conclusion Theoretical analysis and experimen- tal results show that the algorithm is reversible and effective and secure.

关 键 词：可逆水印 插值 双线性插值 图像放大 信息隐藏 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]