一种改进的基于循环块相关的脆弱水印认证算法  

An Improved Fragile Watermarking Authentication Algorithm Based on Circular-Block Dependence

作　　者：李占德[1] 张政保[1] 刘会英[1] 文家福[1] 

机构地区：[1]军械工程学院计算机工程系,河北石家庄050003

出　　处：《计算机技术与发展》2010年第9期161-163,167,共4页Computer Technology and Development

基　　金：河北省自然科学基金项目(05213579)

摘　　要：针对一种基于循环块相关的脆弱水印认证算法不能有效抵抗伪认证攻击的安全缺陷,分析并提出了相应的改进算法。首先利用Logestic混沌映射生成基于图像块特征的水印信息;然后采用改进的基于循环块相关的嵌入策略,将图像块水印信息分为两部分并分别嵌入块自身和相关块的最低有效位平面(LSB);最后对各图像块的LSB进行混沌置乱。实验结果表明,该算法不仅能很好地抵抗伪认证攻击,且具有块独立算法的篡改定位精度,能很好地实现图像认证功能。Aiming at defects of circular-block dependent fragile watermarking authentication algorithm nonresistance to the pseudo-authentication attack,an improved algorithm is proposed in this paper.Firstly,using the logistic chaos generates the image-block watermark;Then,divide the image-block watermark into two parts,with the improved block-dependent embedding strategy,respectively embedding each part into the LSB of the two dependent blocks;Last,use the logistic chaos to scramble each image-block＇s LSB.Experimental results show that the improved algorithm not only enhances the algorithm＇s ability to resist the pseudo-authentication,but also efficiently improves the tamper localization accuracy,and works well on image authentication.

关 键 词：脆弱水印 循环块相关 混沌系统 篡改定位 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]