图像的自嵌入及窜改的检测和恢复算法  

Tamper Detection and Self Recovery of Images Using Self-Embedding

作　　者：张鸿宾[1] 杨成[1] 

机构地区：[1]北京工业大学计算机学院,北京100022

出　　处：《电子学报》2004年第2期196-199,共4页Acta Electronica Sinica

基　　金：国家自然科学基金 (No 60 0 750 0 2 ) ;北京市自然科学基金 (No 4992 0 0 2 ) ;863计划 (No 2 0 0 1AA1 4 4 0 80 ) ;北京市教委科技发展计划

摘　　要：提出一种图像自嵌入的水印算法 .它将一个图像的主要内容嵌入该图像自身之中 .该算法不仅能检测和定位对图像的窜改 ,而且能恢复被损坏的图像内容 .算法的基本思路是把一个图像块的主要DCT系数经过量化、编码和加密后 ,嵌入另一个图像块的最低位之中 .依据大量图像DCT量化系数的统计性质 ,本文仔细设计了主要DCT系数的编码表 ,使它既能满足水印负荷的要求 ,又能保证图像恢复时有较好的质量 .分析了水印嵌入块和原图像块间偏移值应该满足的条件和设计方法 .该算法为单向、不可逆的 。A scheme for self-embedding an image into itself is proposed as a means for detecting and locating tamper, and self-recovering. The image is divided into small 8×8 blocks and each block is DCT transformed. A specified number of the lower frequency DCT coefficients are quantized and encoded using a fixed number of bits. The number of coefficients and their bit lengths are carefully chosen, according to the statistical property of these coefficients, the resulting bit-string for each block satisfies the payload of each block and has good self-recovering capability. The information about one block B (the bit string) is inserted into the LSB of another distant block, which is separated from B with an offset. We analyzed the method for choosing the offset. The proposed scheme is an one way watermarking and secure algorithm, and can well resist possible forged attack.

关 键 词：多媒体认证 数字水印 RSA公钥算法 自嵌入 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]