An Image Authentication Method by Grouping Most Significant Bits  

作　　者：Chi-Shiang Chan Yuan-Yu Tsai Chao-Liang Liu 

机构地区：[1]the Department of Applied Informatics and Multimedia,Asia University

出　　处：《Journal of Electronic Science and Technology》2013年第1期33-37,共5页电子科技学刊（英文版）

基　　金：supported by the Asia University,Taiwan under Grant No.100-ASIA-38

摘　　要：In 2011, Chan proposed an image authentication method by producing the parity check bits from pixels whose bits have been rearranged. Due to this rearrangement, the value of the most-significant bit of each tampered pixel can be determined according to its parity check bits. With the help of the most-significant bit of the pixel, the pixel can be recovered by selecting two possible （7, 4） Hamming code words. However, if the distance between two Hamming code words is within a certain range, incorrect selection may occur. Chan＇s method added one additional bit to indicate the correct one. It is trivial that this may degrade the quality of the authenticated image. In this paper, we group four most-significant bits into different groups to form a mapping codebook and the mapping codebook is used to produce authentication data instead of the （7, 4） Hamming code book. The experimental results show that the proposed method has a greater ability to recover tampered areas.In 2011, Chan proposed an image authentication method by producing the parity check bits from pixels whose bits have been rearranged. Due to this rearrangement, the value of the most-significant bit of each tampered pixel can be determined according to its parity check bits. With the help of the most-significant bit of the pixel, the pixel can be recovered by selecting two possible （7, 4） Hamming code words. However, if the distance between two Hamming code words is within a certain range, incorrect selection may occur. Chan＇s method added one additional bit to indicate the correct one. It is trivial that this may degrade the quality of the authenticated image. In this paper, we group four most-significant bits into different groups to form a mapping codebook and the mapping codebook is used to produce authentication data instead of the （7, 4） Hamming code book. The experimental results show that the proposed method has a greater ability to recover tampered areas.

关 键 词：Image authentication information hiding tamper proofing. 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]