对合参数变换耦合双随机相位的图像加密算法

Image Encryption Algorithm Based on Involuntary Parametric Transform Coupled Double Random Phase

为了解决当前双随机相位加密系统的明文与密文函数之间相对简单的依赖关系,导致加密系统的安全性能不高等难题,引入非标准二阶互逆-正交参数变换,设计对合参数变换,并将其引入到双随机相位加密系统中,提出了对合参数变换耦合双随机相位的图像加密算法。利用位置集合置乱技术扰乱明文;由对合参数变换与相位矩阵,设计加密函数,完成置乱像素的扩散;并将递归运算嵌入到对合参数变换中,实现加密系统的简单结构及快速计算。仿真结果表明:与其他互逆-正交参数变换加密机制相比,本加密算法更安全,熵值约为7.99986,相邻像素的自相关性更低;且密钥空间巨大,获取的密文具有更高的抗强力攻击性能,能防止图像被肆意篡改。

In order to solve these detects such as poor safety performance of current double random phase encryption system with relatively simple dependencies between the initial plaintext functions and the ciphertext function,the involuntary parametric transform is designed to embed into double random phase encryption system parameters by introducing non-standard second order reciprocal-orthogonal transformation.The initial image is permuted by position set permutation technique,and the permutation pixels are diffused by designing the encryption function of this algorithm.The recursive operator is embedded into involuntary parametric transform for its simple construction and fast computation.The simulation results show that compared with other reciprocal-orthogonal transform encryption mechanism,the secure performance of this algorithm is high with entropy value 7.99986,and lower autocorrelation of adjacent pixels.The key space is huge to improve the anti-attack capability and prevent images being wantonly tampered.