基于变换域的Patchwork水印改进算法  

An Improved Patchwork Watermarking Algorithm based on Image

作　　者：甘霖 杨榆[1] 

机构地区：[1]北京邮电大学信息安全中心,北京100876

出　　处：《成都信息工程大学学报》2017年第6期623-627,共5页Journal of Chengdu University of Information Technology

基　　金：国家重点研发计划课题资助项目(2016YFF0204001);国家自然科学基金资助项目(61121061)

摘　　要：Patchwork水印算法是一种经典的水印算法,具有鲁棒性强、易于实现等优点。然而该算法的缺陷也比较明显,即算法直接在空域进行水印的嵌入容易引起图像视觉上的变化。针对经典Patchwork算法在空域嵌入导致算法透明性较差这一缺陷,提出一种在变换域嵌入水印的Patchwork水印改进算法,以期提高Patchwork算法的透明性。提出的算法使用DCT变换将水印的嵌入空间由空域改为变换域,并且结合人类视觉系统的特点进一步抵消水印嵌入带来的视觉影响。实验结果表明,提出的Patchwork水印改进算法在大幅度提高算法透明性的同时,并不降低算法的鲁棒性。Patchwork watermarking algorithm is a classic watermarking algorithm which is robust and easy to implement.However,the defect of the algorithm isobvious,that is,the algorithm directly embeds watermark in the space domain,which leads to visual changes of the image.In view of the weakness of the poor transparency of the classical Patchwork algorithm,this paper propose an improved Patchwork watermarking algorithm based on image to improve the transparency of Patchwork algorithm,which uses DCT transform to change the embedding space of the watermark from space domain to transform domain and combines the characteristics of human visual system to further counteract the visual influence caused by watermark embedding.Experimental results show that the proposed Patchwork watermarking algorithm does not reduce the robustness of the algorithm greatly while improving the transparency of the algorithm.

关 键 词：Patchwork DCT变换 人类视觉系统 透明性 

分 类 号：TP309.2[自动化与计算机技术—计算机系统结构]