Li Shouliang, Ding Weikang, Yin Benshun, Zhang Tongfeng, Ma Yide
School of Information Science and Engineering, Lanzhou University, Lanzhou 730000, China.
Entropy (Basel). 2018 Jun 14;20(6):463. doi: 10.3390/e20060463.
With the popularity of the Internet, the transmission of images has become more frequent. It is of great significance to study efficient and secure image encryption algorithms. Based on traditional Logistic maps and consideration of delay, we propose a new one-dimensional (1D) delay and linearly coupled Logistic chaotic map (DLCL) in this paper. Time delay is a common phenomenon in various complex systems in nature, and it will greatly change the dynamic characteristics of the system. The map is analyzed in terms of trajectory, Lyapunov exponent (LE) and Permutation entropy (PE). The results show that this map has wide chaotic range, better ergodicity and larger maximum LE in comparison with some existing chaotic maps. A new method of color image encryption is put forward based on DLCL. In proposed encryption algorithm, after various analysis, it has good encryption performance, and the key used for scrambling is related to the original image. It is illustrated by simulation results that the ciphered images have good pseudo randomness through our method. The proposed encryption algorithm has large key space and can effectively resist differential attack and chosen plaintext attack.
随着互联网的普及，图像的传输变得更加频繁。研究高效且安全的图像加密算法具有重要意义。基于传统的逻辑斯谛映射并考虑延迟因素，本文提出了一种新的一维（1D）延迟线性耦合逻辑斯谛混沌映射（DLCL）。时间延迟是自然界各种复杂系统中常见的现象，它会极大地改变系统的动态特性。从轨迹、李雅普诺夫指数（LE）和排列熵（PE）方面对该映射进行了分析。结果表明，与一些现有的混沌映射相比，该映射具有较宽的混沌范围、更好的遍历性和更大的最大李雅普诺夫指数。基于DLCL提出了一种彩色图像加密的新方法。在所提出的加密算法中，经过各种分析，它具有良好的加密性能，且用于置乱的密钥与原始图像相关。仿真结果表明，通过我们的方法加密后的图像具有良好的伪随机性。所提出的加密算法具有较大的密钥空间，能够有效抵御差分攻击和选择明文攻击。
