中文摘要：

基于logistic映射和时空混沌系统,设计了一个密钥长度为256bit的图像分组密码算法,将256bit的明文图像分组加密为等长的密文图像.该算法引入的辅助密钥和设计的迭代次数敏感地依赖于明文分组和密钥,交替迭代混沌系统及Arnold映射实现了像素值的扰乱和位置置乱.计算机仿真和密码分析表明,该算法具有对明文和密钥敏感、密钥空间大和可扩展性强等特点,具有良好的加密效果和较强的抗攻击性能,适用于安全通信领域.

英文摘要：

A block image encryption algorithm with a 256 bit key was designed based on a logistic map and a spatiotemporal chaotic system.The algorithm encrypts a block of original image into a block of cipher image with the same length of 256 bit.An auxiliary key brought in and iterations designed in the algorithm are sensitive to the original image and secret keys.An alternating iterative chaotic system and an Arnold map disturb pixel values and shuffle the positions of pixels.The results of computer simulation and cryptanalysis show that the algorithm is characteristic of excellent sensitivity to the original image and keys,large secret key space and high expansibility.The algorithm also has excellent effective encryption and strong anti-attacking performance.It is indicated that the algorithm is suitable for security communication.