基于分数阶Logistic映射的彩色图像加密

Color Image Encryption Based on the Fractional Logistic Map

分数阶Logistic混沌映射具有模型简单、动力学行为复杂,且易计算机编程的优点.基于分数阶Logistic混沌映射,结合DNA编码,提出了一种分数阶图像加密算法.利用分数阶Logistic混沌产生密钥链和DNA编码序列,再对彩色图像的三个像素层进行像素置乱,改变像素位置,将加密结果像素层组成一张灰度图.结果分析表明,分数阶图像加密不仅改变了原有图像的大小,还改变了图像的类型.通过对该算法从密钥敏感性分析、统计分析和相关性分析,分数阶图像加密算法鲁棒性、密钥敏感性强,极大地提升了密钥空间.

The fractional Logistic chaotic map has a simple form but holds complex dynamic behavior and can be readily generated on computer. In this paper,an image encryption algorithm is proposed by using the map and DNA coding. The fractional chaotic map generates a key chain. Each pixel layer of the RGB image is encrypted through changing pixel locations. A gray scale image is obtained by combination of the three encryption results. The encrypted image not only changes the size of the original image but the type. Through the security analysis including key sensitivity,statistics and correlation analysis,the results show that the algorithm has good robustness,key sensitivity and enhanced the key space and leads to high security.