医学图像可逆数字水印防溢出处理研究.pdf

162 2013 ，49（23） Computer Engineering and Applications 计算机工程与应用 医学图像可逆数字水印防溢出处理研究 1，2 1 3 1 邓小鸿 ，陈志刚 ，刘惠文 ，翦 鹏 1 ，2 1 3 1 DENG Xiaohong , CHEN Zhigang , LIU Huiwen , JIAN Peng 1.中南大学 信息科学与工程学院，长沙 410083 2.江西理工大学 应用科学学院，江西 赣州 341000 3.中南大学 软件学院，长沙 410083 1.School of Information Science and Engineering, Central South University, Changsha 410083, China 2.College of Applied Science, Jiangxi University of Science and Technology, Ganzhou, Jiangxi 341000, China 3.School of Software, Central South University, Changsha 410083, China DENG Xiaohong, CHEN Zhigang, LIU Huiwen, et al. Study on preventing overflow and underflow of reversible digital watermarking for medical images. Computer Engineering and Applications, 2013, 49（23）：162-165. Abstract ：In order to effectively solve the overflow and underflow problems during watermark embedding for medical images, three common methods of preventing overflow and underflow mentioned in literatures, including module-256, location map and histogram narrowing have been tested. The experimental results give the effects brought by different three methods to reversible watermarking with respect to several aspects including embedding capacity and image quality and demonstrate the priority of histogram narrowing method. Analyses show the preventing overflow and underflow algorithm is the key step to ensure the per- formance of lossless watermarking, and its choice depends not only on the specific reversible watermarking approach but also on image ’s different modality specificities. Key words ：medical image; reversible watermarking; overflow; underflow; histogram 摘 要：针对医学图像数字水印嵌入过程中出现的大量溢出现象，对文献中提及的几种常见防溢出算法——module-256、 位置映射和直方图压缩方法进行了对比实验。实验结果给出了三种方法对可逆水印算法的容量和图像质量造成的影响， 证明了直方图压缩方法的优越性。分析指出防溢出算法是医学图像可逆数字水印性能的关键，其算法选择取决于具体的 可逆水印算法和医学载体图像的不同形态。 关键词：医学图像；可逆水印；上溢；下溢；直方图 文献标志码：A 中图分类号：TP309