基于DNA编码运算和混沌系统的图像分块加密算法

针对当前基于DNA编码运算的图像加密算法复杂度和安全性较低的问题,提出一种图像分块加密算法.利用Lo-gistic混沌映射产生与明文图像大小相同的随机矩阵,然后对明文图像和随机矩阵进行分块,每个子块的DNA编解码方式以及相互之间的DNA运算均由Chen超混沌系统产生的混沌序列动态决定,同时引入密文反馈机制,使算法得到更好的扩散效果.此外,算法的密钥由明文图像生成,实现了一次一密的加密.仿真实验结果和分析表明加密效果良好,算法利用了DNA可选择编码方式和运算操作丰富的特点,具有较高的复杂度和安全性,密钥空间大,能抵抗多种攻击.

Image block encryption algorithm based on DNA code operation and chaotic system

Aiming at the comparatively low complexity and security of current image encryption algorithm based on DNA code operation,an image block encryption algorithm is proposed in this paper.A random matrix which has the same size as plain image matrix is generated by Logistic chaotic map,then the two matrices are divided into blocks,the type of coding and operation in each block is decided by the sequence generated by Chen hyper-chaotic system.Ciphertext feedback mechanism is employed to get better diffusion effect,in addition,the algorithm achieves the scheme of'one time one key'as the keys are generated by plain image.The results and analysis of experiment demonstrate that the encryption effect is good,the proposed algorithm makes use of the diversity of DNA coding and operation,has high complexity and security,large key space and resistance to many kinds of attacks.