一种基于Zigzag变换及混沌序列的图像加密方法研究与实现  

Research and Implementation of Image Encryption Algorithm Based on Zigzag Transformation and Chaotic Sequence

作　　者：马文涛[1] 余平安[1] 

机构地区：[1]华中科技大学,湖北武汉430074

出　　处：《现代电子技术》2008年第5期104-106,109,共4页Modern Electronics Technique

摘　　要：给出一种在二维小波分解基础上,应用Zigzag变换和混沌序列相组合对数字图像进行加密的方法,可以达到密码学中混淆和扩散的目的。该方法应用二维小波分解算法分解明文图像,首先对分解的全部频率系数进行Zigzag变换,再应用变换后的系数进行重构,得到一次加密结果,然后对其应用混沌序列设计算法进行再次加密,从而完成图像的最终加密。解密是加密的逆过程。把该算法分别应用于彩色图像的R,G,B层,达到了对一幅彩色图像加密的目的。仿真试验结果证明了该方法的有效性,分析表明该方法有很大的密钥空间,且具有一定抵抗恶意攻击的鲁棒性和抗统计攻击的能力。Based on wavelet decompose, this paper presents an image encryption algorithm which applying Zigzag transformation and chaotic sequence are combined,it,can attain the purpose of confusion and diffusion in cryptography. The method decomposes plaintext image by using wavelet decompose algorithm. Firstly, all decomposed frequency coefficient are transformed by Zigzag. Secendly,applying the transformed coefficient to restructure image, then the first encryption result can be attained. Thirldly,applying chaotic sequence to encrypt the first result again with the composed algorithm,then the final encryption of the image is finished. Decryption is the contrary process of encryption. The paper also applies the algorithm to R,G,B compo- nent of one color image separately,and it can reach the intention of encryption of color image. The simulation results show the validity of the method. Through theoretical analysis,the method is not only of more larger secret key space, but also of the robust resisting vicious attack and the ability resisting statistical attack.

关 键 词：小波分解 Zigzag变换 混沌序列 HENON映射 正弦平方映射 图像加密 

分 类 号：TP309.7[自动化与计算机技术—计算机系统结构]