基于矩阵四向扩散的超混沌图像加密算法

目前高强度的超混沌图像加密方法普遍在一维序列上实现扩散过程，但较慢的加密速度导致其实用价值不高。基于此，本文提出一种基于矩阵四向扩散的超混沌图像加密算法。首先，量化重构超混沌系统迭代产生的原始序列，生成与明文图像尺寸相同的密钥矩阵；然后，由低维混沌系统生成扩散过程所需的初始向量；最后，在图像矩阵上以行向量、列向量为计算单元，依次从上下左右4个方向完成像素信息的全局扩散。仿真实验结果表明，本文算法能够抵御选择明文、差分分析等攻击手段，同时算法时间复杂度仅为线性阶，兼具安全性能和运行效率，在图像实时保密通信领域具有较好的效果。

A Novel Hyper Chaotic Image Encryption Algorithm Using Four Directional Diffusion Based on Matrix

A new hyper chaotic image encryption algorithm using four directional diffusion on matrix is proposed to overcome the low efficiency of most hyper chaotic image encryption algorithm. Firstly, the original sequence generated by the hyper chaotic system is quantized and reconstructed to generate the key matrix with the same size as the plaintext image. Secondly, the initial vector required by the diffusion process is generated by the low-dimensional chaotic system. Finally, the vectorized operation is used to complete the global diffusion of pixel information from the top, bottom, left and right. The simulation results show that the algorithm can resist the attacks such as plaintext selection and differential analysis, and the time complexity of the algorithm is only O(M+N), which has both security performance and operation efficiency, and has a good effect  in the field of image real-time secure communication.