一种基于混沌系统及Henon映射的快速图像加密算法

提出一种新的基于混沌系统及Henon映射的图像加密算法．使用经过取模处理的可逆二维非线性Henon映射对各像素点的灰度值进行链式循环迭代，每个迭代环节中Henon映射的参数与迭代次数依次取自一维混沌映射生成的混沌序列．该算法设计简单、运算快速、解密准确，尤其是解决了基于混沌或非线性变换的加密算法中普遍存在的由于计算机的有限精度或各计算机精度不同所导致的解密失败的难题，避免了常用置乱变换算法固有的缺陷及密码强度的不足，具有很高的安全性．

A Fast Image Encryption Algorithm Based on Chaos System and Henon Map

On the basis of chaos system and Henon map, a new fast image encryption algorithm is presented. Two-dimensional reversible nonlinear Henon map that is dealt with mould operation is utilized to circularly iterate gray value of pixels by chain type. In each step, iterated times and parameters of Henon map are sequentially set as values of a chaotic sequence which is generated by one-dimensional chaotic map. In this algorithm the computational speed is fast due to simple design and it is accurate to decipher cipher text. Especially, it .solves difficult problem of failure in deciphering because of limited precision and different precision in different computers generally existing in algorithms based on chaos or nonlinear map. The algorithm avoids inherent defects and inadequateness of cryptological intensity of other algorithms adopting permutation transform and thus has super security.