基于混沌压缩感知的图像加密算法研究

【作者】 王洋；

【导师】 赵冰； 李剑；

【作者基本信息】 黑龙江大学 ， 新一代电子信息技术（含量子技术等）， 2025， 硕士

【摘要】 在信息传输过程中,图像数据面临着被非法窃取以及恶意篡改等风险,研究如何提升图像数据在传输过程和存储设备中的安全性能显得非常重要。目前图像加密方案部分算法存在与明文图像相关性弱、图像重构质量差、传输和存储效率低、硬件实现困难等问题,因此提升图像信息在传输过程与硬件加密中的安全性及可行性具有重要意义。本文基于Lyapunov指数反推法构建了一个具有三个正Lyapunov指数的三维离散超混沌系统,该系统具有复杂的动力学特征。为了在确保加密安全性的前提下,提高硬件加密资源的利用效率,对三维离散超混沌系统进行简化,以更好地适应硬件实现。将该三维离散超混沌系统应用于压缩感知中,提出了一种基于三维离散超混沌系统的图像压缩加密算法。首先对明文图像进行离散小波变换,使用Arnold变换对稀疏系数矩阵进行置乱,缩小稀疏度差异。为了提高算法抵抗差分攻击的能力,由Hash函数生成混沌系统中的密钥,针对不同的明文图像,会生成与之对应的测量矩阵和密钥。依据所构建的三维离散超混沌系统,生成测量矩阵以实现对图像的压缩采样。在图像压缩加密阶段,结合约瑟夫环以及伪随机序列对压缩后的图像进行置乱操作,利用异或运算完成对图像的扩散处理。通过仿真实验分析,验证了该算法具有较高的安全性,能够更好的保障数字图像传输的安全性。最后基于该图像压缩加密算法框架,设计一种结合上位机和FPGA的混沌图像压缩加密实现方案,在FPGA中实现三维离散超混沌系统、伪随机序列生成、串口发送、置乱扩散加密以及LCD显示,通过实验和结果分析证明了方案的硬件可实现性。更多还原

【Abstract】 In the process of information transmission,image data faces the risk of being illegally stolen and maliciously tampered with,so it is very important to study how to improve the security performance of image data in the transmission process and storage devices.Currently,some algorithms of image encryption schemes have problems such as weak correlation with plaintext images,poor quality of image reconstruction,low efficiency of transmission and storage,and difficulties in hardware realization,so it is of great significance to improve the security and feasibility of image information in the transmission process and hardware encryption.In this paper,a new three-dimensional discrete hyperchaotic system is constructed based on the Lyapunov exponential backpropagation method,which exists three positive Lyapunov exponentials and has complex dynamics.In order to improve the utilization efficiency of hardware encryption resources while ensuring cryptographic security,the three-dimensional discrete hyperchaotic system is simplified to better fit the hardware implementation.An image compression-encryption algorithm is developed by integrating the proposed three-dimensional discrete hyperchaotic system into the compressed sensing framework.Firstly,a discrete wavelet transform is performed on the plaintext image,and the sparse coefficient matrix is discretized using the Arnold transform to reduce the sparsity difference.In order to improve the ability of the algorithm to resist differential attacks,the key in the chaotic system is generated by the hash function,and for different plaintext images,the corresponding measurement matrices and keys are generated.Based on the constructed three-dimensional discrete hyper chaotic system,the measurement matrix is generated to realize the compressive sampling of the image.In the stage of image compression and encryption,combining Josephus ring and pseudo-random sequences to disrupt the compressed image,the diffusion of the image is accomplished by using the heteroscedastic operation.Through the simulation experiment analysis,it is verified that the algorithm has high security and can better guarantee the security of digital image transmission.Finally,under the design framework of this image compression and encryption scheme,we design a chaotic image compression and encryption scheme that combines the host computer and FPGA,and realize the three-dimensional discrete super chaotic system,pseudo-random sequence generation,serial port transmission,disrupted diffusion encryption,and LCD display in FPGA,which proves the hardware realizability of the scheme through the experiments and the analysis of the results.更多还原