基于Duffing映射与遗传操作的图像加密方法

Image Encryption Algorithm Based on Duffing Map and Genetic Operators

提出了一种基于混沌系统和遗传操作的图像加密方案.首先,使用SHA-3算法计算明文图像的哈希值,作为混沌系统的初始值;其次,利用混沌映射对初始条件的敏感性与伪随机性,迭代Logistic映射得到伪随机序列并生成希尔矩阵,对图像进行置乱与置换;再次,结合Duffing映射与DNA编码技术,利用遗传操作在位水平上,实现像素的选择、交叉与变异来完成像素的扩散与置乱,显著增加算法的破译难度;最后,通过与混沌序列进行双向异或运算,进一步增强算法的混淆和扩散特性.实验和安全性分析结果表明,该算法对密钥的敏感性强,能有效抵抗统计攻击和差分攻击等,加密效果得到显著提升.

In this paper,an image encryption scheme based on chaotic systems and genetic operations was proposed.Firstly the SHA-3 algorithm was used to calculate the hash value of the plaintext image and input the key as the initial values of the chaotic system.Secondly the sensitivity of the chaotic map to initial conditions and pseudo-randomness were used to obtain pseudo-random sequence by iterative the Logistic map,and generate the Hill matrix to carry out image scrambling and permutation.Thirdly combining the Duffing map and DNA coding technology,the selection,crossover and mutation of pixels were realized at the level of genetic operations to achieve pixel diffusion and scrambling,which significantly increased the decoding difficulty of the algorithm.Finally,bidirectional exclusive OR operations with chaotic sequence was carried out to further enhance the confusion and diffusion characteristics of the algorithm.The experimental and security analysis results showed the algorithm was sensitive to the keys and could effectively resist statistical attacks and differential attacks,and the image encryption effect and performance could be significantly improved.