基于二维Arnold映射的彩色图像加密算法

Color Image Encryption Algorithm Based on Two-dimensional Arnold Mapping

根据彩色图像的特点,基于二维Arnold映射和Logistic映射设计了一种彩色图像加密算法.该算法由在不同颜色分量上的交叉扩散操作、基于伪随机序列的替换操作和基于Arnold映射的置乱操作组成.交叉扩散操作在整个密文图像上散播明文图像每一比特的影响,改变了明文图像的统计特性.置乱操作每轮用于混沌伪随机序列发生器和置乱操作的参数均由初始密钥和(0,0)点的像素值共同决定.计算机仿真实验与安全性分析表明,该算法能有效地抵抗选择明文攻击和已知明文攻击,密钥空间较大,算法具有较高的安全性.

According to the characteristics of the color image, the color image encryption algorithm is designed based on two-dimen- sional Arnold mapping and Logistic mapping. This algorithm consists of the iterative diffusion operation in different color compo- nents, the replacement operation based on Pseudo-random sequence and the scrambling operation on the basis of Arnold mapping. The influence of the iterative diffusion operation on the spread of the whole Ciphertext image is able to change the statistical characteristics of the plaintext image. The chaotic pseudo-random sequence generator and the scrambling operation parameters are jointly decided by the initial key and the pixel values of （ 0,0） in each round. The Computer simulation and security analysis shows that this algorithm can effectively resist the known plaintext attack and the chosen plaintext attack, and make the key space larger. This algorithm has the higher security.