中文摘要：

针对被动攻击下的信息隐藏系统,建立一个具体的信息隐藏统计模型,从安全性、失真距离度量、信道容量3个角度全面分析该模型.信道容量问题的求解可以抽象为1个受到平均汉明失真距离和平均安全性约束的最优化问题,只要给定需要的参数就可以运用最优化理论得到最优解,最后求解出原始载体序列和秘密信息序列均服从均匀分布时统计模型的信道容量.

英文摘要：

With respect to information hiding system under passive attacks, a concrete statistical model of information hiding system was built and its performance was analyzed, including security, distortion distance metric, and channel capacity. The solution to channel capacity can be regarded, subjected to average hamming distortion distance and average security coefficient, as an optimization problem, . As long as the required parameters are given, the optimization problem of channel capacity will be easy be solved when using optimization theory. Finally, the channel capacity of statistical model is derived on the condition that both original cover sequence and secret information sequence obey to uniform distributions.