如何设计高阶统计安全的大容量隐写算法是当前隐写研究的难点和热点。该文基于Markov链安全性指标和动态补偿的思路，提出一种二阶统计保持的隐写算法。该算法在不降低嵌入量的前提下尽量保持了载体图像的二阶统计特性。实验结果表明，该算法在较大容量数据嵌入过程中，能较好保持二阶统计特性，取得隐写安全性的提高。

It has been a difficulty and hotspot in steganography research that how to design large payload steganographic algorithm while high-order statistical security is ensured. Based on the Markov Chain security benchmarking and dynamic compensating means, a novel second-order distribution maintained steganographic method was proposed, which preserves the second-order distribution of the cover image and the embedded payload is unreduced. Experimental results showed that the proposed algorithm can maintain the second-order distribution of cover image while larger secret information is embedded, and improve the steganographic security.