基于分数阶超混沌的新图像加密算法

分数阶混沌系统具有复杂的动力学特性,因此在图像加密中具有更高的安全性.首先,利用离散logistic混沌系统对彩色数字图像的三基色平面进行置乱.然后,利用分数阶CYQY超混沌系统对置乱图像的三基色通道进行逐像素替换.为提高明文对密文的敏感性,通过明文图像产生的小数对作为密钥的阶次、参数和系统初始值等进行扰动,理论分析和对彩色Baboon图像的仿真实验均表明,该算法加密效果好且能有效抵抗各种攻击.

New algorithm for image encryption based on fractional order chaotic system

Fractional order chaotic system has complex dynamic characteristics, so it has higher security in image encryption. Firstly the digital image was scrambled by the discrete Logistic chaos. Then the red, green and blue channels of the scrambled image were confused by the fractional order CYQY hyperchaos. To improve the sensitivity of cipher text to plaintext, this paper proposes a new image encryption algorithm. In the algorithm a perturbation digit between 0 and 1 based on every pixel value of plaintext can affect fractal order, parameter and initial state vector of chaos systems. Both theoretical analysis and experimental results show that the algorithm sufficiently encrypts digital image, and encryption image can resist some kinds of external attacks.