基于一类复混沌系统的图像加密研究

Research on Image Encryption Based on a Class of Complex Chaotic System

基于对数字图像信息安全问题,构造了一个新的复混沌系统,利用耗散性、李雅普诺夫指数、平衡点的稳定性、初值敏感性等方法,对其进行动力学特征分析,分析结果表明,该复混沌系统具有良好的混沌特性。采用二维图像展成一维向量后的置乱方法和基于GF(2^(17))有限域来实现扩散处理方法,对该系统产生的混沌序列进行Matlab仿真,实现了基本数字图像加密,并对此加密方法进行安全性分析,分析结果表明,该加密方式对多种密文攻击具有较好的抵抗力。

Based on the problem of digital image information security,a new complex chaotic system is constructed in this paper,and its dynamic characteristics are analyzed by means of dissipation,Lyapunov exponent,stability of equilibrium point,initial value sensitivity and so on.The results show that the complex chaotic system has good chaotic characteristics.By using the scrambling method after the two-dimensional image to expand into one-dimensional vector and the diffusion processing method based on finite field,the chaotic sequence generated by the system is simulated by Matlab,and the basic digital image encryption is realized,and the security of the encryption method is analyzed.The results show that the encryption method has good resistance to many kinds of ciphertext attacks.