基于脆弱水印的图像认证算法研究  

Image Authentication Scheme Research Based on Fragile Watermarking

作　　者：张宪海[1] 杨永田[1] 

机构地区：[1]哈尔滨工程大学计算机科学与技术学院,黑龙江哈尔滨150001

出　　处：《电子学报》2007年第1期34-39,共6页Acta Electronica Sinica

摘　　要：很多基于分块的图像认证算法为了提高安全性,采用大分块或者分块相关技术,因而牺牲了定位精度.通过对各种攻击的分析,提出了一种基于脆弱水印的图像认证方案.使用SHA512算法和基于背包问题的单向函数来产生水印,使用滑动窗口技术和层次结构来嵌入水印,使强加密算法在小分块上得以应用.该方案不但能够抵抗矢量量化等目前已知的各种攻击,而且能够将篡改定位到2×2大小的像素块上.理论分析和实验数据表明,该方案在保证系统安全性的同时,有效地提高了篡改定位的精度.Big blocks or blocks relation techniques are applied in several image authentication schemes to improve security at the cost of localization accuracy is decreased. In this paper, an image authentication scheme based on fragile watermarking is proposed by means of the analysis of all kinds of attacks. On the basis of small blocks, the strong cryptography algorithm is applied, the watermarking is generated by SHA512 and one-way function based on knapsack problem, and is embedded via sliding window and hierarchical structure. The approach can not only resists all kinds of attacks such as vector quanfization（VQ）, but also localize a tamper to a 2 × 2 block pixels. Theory analysis and experimental results demonstrate that the proposed scheme improves the accuracy of tamper localization as well as ensure the security.

关 键 词：脆弱水印 层次结构 篡改检测 篡改定位 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]