明文连续LSB隐写的消息检测与提取方法  

Message Detection and Extraction Methods for Plaintext Sequential LSB Steganography

作　　者：徐澈[1] 刘九芬[1] 

机构地区：[1]信息工程大学,河南郑州450001

出　　处：《信息工程大学学报》2017年第2期200-205,共6页Journal of Information Engineering University

摘　　要：当嵌入消息为明文时,利用中英文字节比特位的统计特性,研究针对空域和JPEG域连续LSB(least significant bit)替换\匹配隐写均有效的消息检测和提取方法。首先提取图像像素(或有效DCT系数)的LSB序列,并从该序列的第1字节的每一比特开始进行间隔7采样,得到8条子序列;然后利用子序列中最长0(或1)游程长度的分布,将检测问题转化为假设检验问题,结合中英文字节比特位的统计特性,从而判定图像是否载密;最后将具有最长0(或1)游程的子序列判定为最大优势序列,进而根据最大优势序列内最长0(或1)游程的起止点估计明文消息嵌入的起止点并提取明文消息。实验结果表明了本文方法的可行性与有效性,与现有方法相比,该方法准确度更高,适用范围更广。In the case of plaintext, by using the bit＇ s statistical property of both English and Chinese bytes, the detection and extraction methods for sequential LSB （least significant bit） replacement matching steganography in both spatial and JPEG domain are proposed. First, the LSB sequence of the image pixels （or available DCT coefficients） is extracted and 8 subsequences are obtained with every bit of the first byte as the beginning and 7 sampling interval. Then, by using the distribution of length of the longest 0 （or 1 ） run within subsequences, the detection problem is converted to hy- pothesis test problem. Combined with the bit＇ s statistical property of both English and Chinese bytes, whether the image is a stego image can be determined. Finally, the subsequence with the longest 0 （or 1 ） run is judged to be the largest advantage sequence, and then the starting point and end point of message are estimated according to the starting point and end point of the longest 0 （or 1 ） run in the largest advantage sequence. The embedded message can thus be extracted eventually. The experimental results have proved the feasibility and effectiveness of the methods. Compared with the existing methods, the proposed methods have higher accuracy and wider range of applications.

关 键 词：隐写分析 明文消息 连续LSB隐写 检测 消息提取 

分 类 号：TN918.1[电子电信—通信与信息系统]