【作者】 王威娜； 张新鹏； 王朔中；

【Author】 Wang Weina, Zhang Xinpeng, Wang Shuozhong(School of Communication and Information Engineering, Shanghai University, Shanghai 200072; v

【机构】 上海大学通信与信息工程学院；

【摘要】 一种有代表性的密写方法是根据像素间相关性来进行秘密信息的嵌入,例如基于相邻像素差值的边缘匹配(SM)密写法。本文指出SM密写会引起像素灰度差值直方图统计特性的异常,这一性质提供了检测秘密信息存在性和估计嵌入信息量的线索,由此提出一种有效的SM密写分析法。以嵌入率α为参数对密写图像像素灰度差值直方图进行分段拟合,通过寻找全局最佳拟合实现密写分析并估计嵌入率,具有实现简单、计算量小的优点。实验表明该方法的有效性。更多还原

【Abstract】 A typical steganographic technique such as the side match (SM) approach makes use of correlation between neighboring pixels. It is shown in this paper that SM, which inserts secret data in neighboring pixel-value differences, inevitably causes abnormality in the pixel-value difference histogram. This provides a clue for staganalysis. A new method is thus proposed to analyze SM steganography and estimate the payload. An assumed embedding rate a is used to calculate a set of local histograms in sections of difference values by means of curve fitting. A globally optimal histogram fitting is then obtained by adjusting the a value to achieve a smooth overall histogram. The algorithm can be easily implemented. Experimental results show the effectiveness of the proposed technique.更多还原