最邻近耦合映射格子耦合非线性混沌映射的图像加密算法研究  

ON IMAGE ENCRYPTION ALGORITHM BASED ON COUPLING NEAREST-NEIGHBOURING COUPLED MAP LATTICES WITH NONLINEAR CHAOTIC MAP

作　　者：郭祖华[1] 王辉[2] 

机构地区：[1]河南机电高等专科学校计算机科学与技术系,河南新乡453003 [2]河南广播电视大学计算机学院,河南郑州450008

出　　处：《计算机应用与软件》2015年第5期283-287,306,共6页Computer Applications and Software

基　　金：河南省教育厅科学技术研究重点项目(13A520221);河南省高等学校青年骨干教师资助计划项目(2011GGJS-198)

摘　　要：针对当前的混沌映射加密算法普遍难以兼顾高计算效率和高安全性,无法满足互联网实时性传输要求等不足。设计了伪随机数同步生成器和并行化掩蔽技术;并引入周期性边界条件,根据2D混沌映射与最邻近耦合映像格子推导出耦合模型,提出一种2D分段非线性混沌映射耦合最邻近耦合映像格子的图像加密算法。通过伪随机数同步生成器生成算法的初始条件与参数,然后根据该耦合模型迭代初始值,得到一组伪随机数;最后利用该伪随机数根据加密变换函数对明文图像进行双向加密,利用S盒对加密元素进行替代,并进行掩蔽处理。仿真结果显示:与当前混沌加密算法相比,该算法安全性以及计算效率更高,可满足互联网实时性传输要求。Current chaotic map cryptographies are commonly difficult to balance high computation efficiency and high security and cannot meet the real-time transmission requirement of internet as well. In light of these shortcomings, we design the synchronised pseudo-random number generator and the parallelised masking technology, and introduce periodic boundary conditions, according to 2D chaotic map and nearest-neighbouring coupled map lattices we derive the coupling model of the algorithm proposed in the paper, and present an image encryption algorithm in which the 2D piecewise nonlinear chaotic map couples the nearest-neighbouring coupled map lattices. Through synchronised pseudo-random number generator we generate the initial conditions and parameters of the proposed algorithm, and then according to the coupling model we derive a group of pseudo-random numbers by iterating the initial values; finally, we use these pseudo-random numbers to carry out bidirectional encryption on plaintext image based on encryption transformation function, and use S-box to substitute the encryption elements, and conduct the masking process. Simulation results show that compared with current chaotic cryptography, the proposed algorithm has higher security and computation efficiency; and can meet the real-time transmission requirement of internet as well.

关 键 词：并行化掩蔽 最邻近耦合映像格子 加密变换函数 伪随机数同步生成器 计算效率 实时性 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]