一种基于块置乱和反馈密钥的图像加密算法

摘要

In analyzing the disadvantages of traditional and iterative image scrambling methods and static image gray value exchange methods, a new algorithm is proposed based on uniform and key feedback mechanism. The key idea of the algorithm is based on uniform block scrambling, and according to different attributes of each pixel dynamically select the different chaotic sequence for gray value encryption based on key feedback mechanism. Matlab simulation results show that the algorithm scrambling algorithm has obvious advantage in terms of relevant adjacent pixels;Feedback mechanisms and dynamic chaotic system makes the gray-scale value has a large key space, excellent resistance to express,ciphertext attack;The time complexity of encryption algorithm is reasonable and the security is high.%在分析传统迭代型图像置乱方法以及静态灰度值加密方法不足的基础上,提出了一种基于图像块位置置乱和动态密钥反馈机制的数字图像加密算法.算法的关键思想是基于分块原理的均匀置乱,以及根据各像素点的不同属性动态选择不同的混沌序列对图像进行基于密钥反馈机制的灰度值加密.仿真结果表明,均匀置乱算法在相邻像素相关性方面优势明显,密文分布均匀；反馈机制和动态选择混沌系统使得灰度值加密算法具有理想的密钥空间,优秀的抗明文、密文攻击能力；整个加密算法时间复杂度合理,安全性高.