Wang Pan, Ding Lina
School of Electronics and Information Engineering, Heilongjiang University of Science and Technology, Harbin 150022, China.
Entropy (Basel). 2024 Jun 22;26(7):536. doi: 10.3390/e26070536.
To construct a chaotic system with complex characteristics and to improve the security of image data, a five-dimensional tri-valued memristor chaotic system with high complexity is innovatively constructed. Firstly, a pressure-controlled tri-valued memristor on Liu's pseudo-four-wing chaotic system is introduced. Through analytical methods, such as Lyapunov exponential map, bifurcation map and attractor phase diagram, it is demonstrated that the new system has rich dynamical behaviors with periodic limit rings varying with the coupling parameter of the system, variable airfoil phenomenon as well as transient chaotic phenomenon of chaos-periodic depending on the system parameter and chaos-quasi-periodic depending on the memristor parameter. The system is simulated with dynamic circuits based on Simulink. Secondly, the differently structured synchronous controls of chaotic systems are realized using a nonlinear feedback control method. Finally, based on the newly constructed five-dimensional chaotic system, a variable parameter color image encryption scheme is proposed to iteratively generate varying chaotic pseudo-random sequences by varying the system parameters, which will be used for repetition-free disambiguation, additive modulo left-shift diffusion and DNA encryption for the three components of RGB of the color image after chunking. The simulation results are analyzed by histogram, information entropy, adjacent pixel correlation, etc., and the images are tested using differential attack, noise attack and geometric attack, as well as analyzing the PSNR and SSIM of the decrypted image quality. The results show that the encryption method has a certain degree of security and can be applied to medical, military and financial fields with more complex environmental requirements.
为构建具有复杂特性的混沌系统并提高图像数据安全性，创新性地构建了一种具有高复杂性的五维三值忆阻器混沌系统。首先，在刘的伪四翼混沌系统上引入了一种压控三值忆阻器。通过李雅普诺夫指数图、分岔图和吸引子相图等解析方法，证明新系统具有丰富的动力学行为，包括随系统耦合参数变化的周期极限环、可变翼型现象以及依赖于系统参数的混沌 - 周期瞬态混沌现象和依赖于忆阻器参数的混沌 - 准周期现象。基于Simulink用动态电路对该系统进行了仿真。其次，利用非线性反馈控制方法实现了混沌系统不同结构的同步控制。最后，基于新构建的五维混沌系统，提出了一种可变参数彩色图像加密方案，通过改变系统参数迭代生成变化的混沌伪随机序列，用于对彩色图像分块后的RGB三个分量进行无重复解歧义、加法模左移扩散和DNA加密。通过直方图、信息熵、相邻像素相关性等对仿真结果进行分析，并使用差分攻击、噪声攻击和几何攻击对图像进行测试，同时分析解密图像质量的PSNR和SSIM。结果表明，该加密方法具有一定的安全性，可应用于对环境要求更复杂的医疗、军事和金融领域。
