基于变参数超混沌系统的多图像加密方法  

Multi-Image Encryption Method Based on Hyperchaotic System with Variable Parameters

作　　者：罗敏[1] 何雨莲 李宜磊[1] 张怀武[1] 文岐业[1] LUO Min;HE Yulian;LI Yilei;ZHANG Huaiwu;WEN Qiye(School of Electronic Science and Engineering,University of Electronic Science and Technology of China,Chengdu 611731)

机构地区：[1]电子科技大学电子科学与工程学院,成都611731

出　　处：《电子科技大学学报》2023年第6期897-905,共9页Journal of University of Electronic Science and Technology of China

基　　金：国家自然科学基金(62235004,61831012);国防科工局科学挑战计划(TZ2018003);科技部国际合作交流专项(2015DFR50870);四川省科技支撑计划(2021JDTD0026,2021YFG0144)。

摘　　要：针对数字图像计算、存储和传输过程中的数据窃取、隐私泄漏等问题,提出了一种基于变参数超混沌系统的多图像加密方法。首先,用一个混沌系统的状态变量对另一个混沌系统的状态参数施加扰动,构造了一个变参数超混沌系统;其次,将输入灰度图像对进行重构,并将其输入SHA-512算法生成初始密钥;然后,将初始密钥输入变参数超混沌系统,迭代生成5组混沌序列,进而对重构图像进行幻方变换,实现像素位置的变换;最后,对幻方变换得到的图像进行S形扩散,实现像素数值的变化,得到了近似均匀分布的密文图像。结果表明,该算法改善了传统图像加密方法的低随机性、低复杂度等缺陷,同时,提高了密文图像的无序性及抵抗常规攻击的能力。Aiming at the problems of data theft and privacy leakage in the process of digital image calculation,storage and transmission,a multi-image encryption method based on hyperchaotic system with variable parameters is proposed.Firstly,the state variables of one chaotic system are used to perturb the state parameters of the other chaotic system,and a hyperchaotic system with variable parameters is constructed.Secondly,the input gray image pair is reconstructed and input into SHA-512 algorithm to generate the initial key.Then,the initial key is input into the hyperchaotic system with variable parameters to generate five groups of chaotic sequences iteratively,and then the reconstructed image is transformed into a magic square to achieve the transformation of pixel positions.Finally,the S-shaped diffusion is performed on the image obtained by the magic square transformation to realize the change of the pixel value,and an approximately uniformly distributed ciphertext image is obtained.The results show that the algorithm improves the low randomness and low complexity of the traditional image encryption method,and at the same time,and improves the disorder of the ciphertext image and the ability of the encryption method to resist conventional attacks.

关 键 词：超混沌系统 图像加密 幻方变换 S形扩散 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]