摘要： 研究了一个基于复合混沌系统的图像加密系统。在该加密系统中，使用具有复杂动力学特性的三维Chen 系统和一维Logistic 混沌映射，并以特定方式将两个混沌系统的输出序列复合起来，通过异或操作实现了对图像的快速加密处理。对该系统进行数值实验和安全性分析，结果表明该系统不但拥有大的密钥空间，而且对密钥和明文很敏感，具有优良的扩散性能和扰乱性能，并能抵抗已知明文攻击和选择明文攻击。

关键词: 复合混沌系统；图像加密；Chen 系统；Logistic 映射

Abstract: This paper proposes an image encryption system based on composite chaotic system. A three dimensional Chen’s system which has a complex dynamical behavior and a one dimensional logistic chaotic mapping are employed in the encryption system. The output sequences of these two chaotic systems are composed by using a special method, and a fast image encryption is realized by means of the bit-wise xor operations. The results of simulation experiments and security analyses indicate that this encryption system not only has a large key space but also has a very sensitivity with respect to the secret key and the original image. The encryption system proposed in this paper possesses perfect diffusion and confusion properties and it can resist the know-plaintext attacks and chosen-plaintext attacks

Key words: Composite chaotic system; Image encryption; Chen’s system; Logistic mapping