摘要
提出一个基于广义Logistic方程构造的二维混沌映射,采用Feigenbaum常数、相图、分岔图分析的方法,研究该混沌映射的非线性动态特性;然后利用该方程生成混沌序列,将混沌序列进行优化改进,生成密钥序列;最后采用输出反馈的加密方式,改变图像的像素值,达到加密的目的。实验仿真表明,该加密算法对密钥非常敏感,有效地提高了抵御选择明文攻击的能力,密文图像信息熵为7.996 94,非常接近理想值8。加密图像像素值具有类随机均匀分布特性,加密图像和明文图像之间的相关性非常接近于0,相邻像素具有零相关特性,而且密钥空间达到299比特。加密方法大大改变了明文图像的像素值,使得密文能够抵御统计攻击。
This paper proposes a 2 - dimensional generalized logistic chaotic mapping, by using the analysis method of phase maps, Feigenbaum constant, bifurcation graphics, we studied its complex nonlinear dynamic activities. And a chaotic sequence is generated from it, then the chaotic sequence is optimized into secret key stream, and output - feedback technology is used in the encryption algo- rithm. The results of experiment show that the encrypted image has random - like distribution behavior of grey values, the extremely sensitive to the key that enhances the ability of resisting the chosen plaintext attack, the information entropy of the cipher image is 7. 996 94, it is very close to the ideal value 8, the correlation between the encrypted image and the plain image is close to 0, the adjacent pix- els have zero co - correlation properties, the key space reachs 299 bits, the encryption method has changed the pixel value of the original image greatly, it makes the ciphertext can resist statistical attack.
出处
《控制工程》
CSCD
北大核心
2014年第2期279-282,289,共5页
Control Engineering of China
基金
国家自然科学基金资助项目(61374086)
湖南省科技计划项目(2013FJ3087
2013FJ3086
2012FJ4329)
