结合四维超混沌系统和位分解的图像加密算法研究  

Image Encryption Algorithm Research by Combining Four Dimensional Hyper-Chaotic System and Bit Decomposition

作　　者：程东升[1] 谭旭[1] 许志良[1] 陈宝文[1] 张运生[1] CHENG Dong-sheng;TAN Xu;XU Zhi-liang;CHEN Bao-wen;ZHANG Yun-sheng(Department of Software Engineering,Shenzhen Institute of Information and Technology Shenzhen Guangdong 518172)

机构地区：[1]深圳信息职业技术学院软件学院,广东深圳518172

出　　处：《电子科技大学学报》2018年第6期906-912,共7页Journal of University of Electronic Science and Technology of China

基　　金：广东省自然科学基金(2015A030313373)

摘　　要：该文针对数字图像传输的安全性问题,基于四维超混沌系统,提出一种新的位级图像加密算法.首先对四维超混沌系统生成的混沌序列进行分类处理,得到具有良好性能的伪随机二进制序列。接着对明文图像进行位分解,得到8个位面,分别对高3位和低5位对应的位面进行行列循环移位置乱,并将置乱后的位面嵌入由伪随机二进制序列得到的4个载体矩阵,对4个载体矩阵执行按位异或运算后得到初步密文。最后,再利用伪随机二进制序列产生的扩散矩阵,对初步密文像素执行线性双向扩散,得到最终的加密图像。数值实验和结果分析显示,算法密钥空间大,可以有效抵御暴力穷举、统计分析和差分分析等恶意攻击,具有较高的安全性。同时,算法也具有较好的执行效率。For the transmission security of digital image,a novel bit-level image encryption algorithm is proposed by using a four dimensional(4D)hyper-chaotic system.Firstly,a pseudo-random binary sequence with good performance is obtained by classifying the chaotic sequences generated from the hyper-chaotic system.Then,the plain-image is decomposed into 8 bit-planes,the higher 3 and lower 5 bit-planes are shuffled separately by using circular shift of their rows and columns,and the resulting bit-planes are further embedded into four carrier matrices generated from the pseudo-random sequences.The preliminary cipher-image is obtained by performing exclusive-OR operation on the four carrier matrices.Finally,a linear pixel diffusion in two directions is performed on the preliminary cipher-image by using the diffusion matrix also generated from the binary sequence,after which the final encrypted image is obtained.Experiments and result analysis demonstrate that the algorithm has a high security with large key space and can resist common attacks including brute-force,statistical and differential analysis,etc.Furthermore,it also has a good efficiency.

关 键 词：混沌序列 混沌系统 图像加密 伪随机 置乱 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]