In this paper, a novel chaotic image encryption algorithm based on extended Zigzag confusion and RNA operation is proposed. Firstly, a novel chaotic system is designed, which can be regarded as an improvement of traditional Logistic map and Sine map. Then it can be used to generate chaotic sequence combined with SHA 512 hash function. Secondly, extended Zigzag confusion scheme is proposed. It not can only process non square matrix, but also can choose from four directions to determine the position where encryption starts. This scheme can solve the problem of some elements keep in the same position in each encryption round. Thirdly, RNA operation is performed. In RNA computing, the choice of operators is determined according to the category of amino acids, and the coding rules of RNA matrix are completely controlled by chaotic sequence, which makes the results of operation more unpredictable. Finally, this encryption method can extend to color image. The data from experimental simulation and performance analysis show that this encryption algorithm has higher safety performance.

提出了一种基于扩展的锯齿形混淆和RNA操作的混沌图像加密算法。首先，设计了一种新颖的混沌系统，可以看作是对传统逻辑图和正弦图的改进。然后可以将其与SHA 512哈希函数结合使用来生成混沌序列。其次，提出了扩展的之字形混淆方案。它不仅可以处理非方阵，而且还可以从四个方向中进行选择以确定加密开始的位置。该方案可以解决在每个加密回合中某些元素保持相同位置的问题。第三，进行RNA操作。在RNA计算中，运算符的选择取决于氨基酸的类别，并且RNA矩阵的编码规则完全受混沌序列控制，这使得运算结果更加不可预测。最后，这种加密方法可以扩展到彩色图像。实验仿真和性能分析数据表明，该加密算法具有较高的安全性能。