基于混沌系统的RGB彩色图像三重置乱算法

针对传统混沌加密系统密钥空间小，序列复杂度不足以及加密系统单一的问题，提出一种新的基于混沌系统的彩色图像三重置乱加密算法。利用Logistic混沌序列对彩色图像各个像素点的三原色(red green blue，RGB)顺序进行置乱，应用Rabinovich超混沌系统产生的四维混沌序列中的一组序列对图像的像素点位置进行分块置乱，使用余下的3组序列分通道对图像离散小波变换后的低频系数进行置乱与扩散。该算法充分利用混沌序列特征，将传统混沌置乱加密方法改进，使彩色图像像素点在RGB 3个通道内进行置乱，并将扩散过程与离散小波变换紧密结合。通过实验仿真，对该算法的密钥空间、敏感度、抗统计攻击能力和抗差分攻击能力进行分析，结果表明，该算法能够安全有效地加密图像，保护图像信息安全。

Triple scrambling algorithm for RGB color image based on chaotic system

Aiming at the problem of small keyspace, insufficient sequence complexity and single encryption system in traditional chaotic encryption system, a new color image triple scrambling encryption algorithm based on chaotic system is proposed. Firstly, the Logistic chaotic sequence is used to scramble the red green blue (RGB) order of each single pixel. Then one of sequences generated from the four dimensional Rabinovich hyperchaotic system is used to scramble the image pixel position by blocking processing. And the rest three of the sequences are used to scramble and diffuse the low frequency coefficients from the image 2-D discrete wavelet transform (DWT) of each RGB channel. The algorithm makes full use of chaotic sequence features to improve the traditional chaos scrambling method, scrambles the color image pixel in all three RGB channels, and combines the diffusion process with DWT closely. Through experimental simulation, the key space, sensitivity, anti-statistical attack ability and anti-differential attack ability of the algorithm are analyzed. The results show that the algorithm can safely and effectively encrypt the image and protect the image information.