一种抗SPA隐写分析的图像隐写策略

Secure Image Steganographic Scheme Resisting SPA Steganalysis

针对SPA隐写分析算法,从理论上分析了F1替换和F-1替换对图像统计量的相反作用,对可以抵抗SPA分析的F1替换和F-1替换的理想嵌入比例关系进行推导,在此基础上提出一种抵抗SPA分析的图像隐写策略,实现了基于误差校正的图像隐写算法。该算法根据混沌映射产生随机位置序列来确定秘密信息的嵌入位置。首先按照F1替换和F-1替换等比率随机嵌入秘密信息,然后对载密图像嵌入秘密信息的长度进行估计,并以误差校正的方式调整F1替换和F-1替换的嵌入比例,最后按照理想嵌入比例将秘密信息随机嵌入在载体图像中。仿真实验结果表明,该算法原理清晰,能够有效抵抗SPA隐写分析,安全性高。同时,对载体图像修改少,嵌入秘密信息的载体图像视觉质量好,提取秘密信息简单。

The SPA steganalysis scheme can estimate the embedding ratio with high precision when using LSB steganography.In order to strengthen the security of the LSB steganographic algorithm,the idea of error correction is applied in our improved steganographic algorithm.Firstly,a chaotic stochastic sequence is used to select the embedding positions,in succession the secret bits are embedded into the selected positions in the equal ratios of F1 and F-1substitution,then the ratios of F1substitution to F-1substitution is adjusted according to the estimated lengths of embedded bits and error correction method,finally the secret bits are embedded into the original image based on the adjusted ratio between F1 substitution and F-1 substitution.Theoretical deduction on the validity of the proposed algorithm is given.Experimental results show strong robustness against SPA steganalysis of the proposed algorithm.