融合二维压缩感知和同步混沌流密码的医学图像加密算法  

Medical Image Encryption Combining 2D Compressive Sensing and Synchronous Chaotic Stream Cipher

作　　者：叶柏君 林卓胜 吴小娜 邓景良 曾慧曲 Ye Baijun;Lin Zhuosheng;Wu Xiaona;Deng Jingliang;Zeng Huiqu(Faculty of Intelligent Manufacturing,Wuyi University,Jiangmen,Guangdong 529020,China)

机构地区：[1]五邑大学智能制造学部,广东江门529020

出　　处：《机电工程技术》2023年第11期32-37,60,共7页Mechanical & Electrical Engineering Technology

基　　金：国家自然科学基金资助项目(61901304)。

摘　　要：提出了一种基于二维压缩感知和同步混沌流密码的医学图像加密算法。首先,通过离散小波变换将明文图像转换为稀疏图像。然后通过迭代同步混沌流密码系统生成3个混沌序列,使用其中2个序列构造出测量矩阵对稀疏图像进行测量;第3个序列构造用于加密的伪随机序列。最后,通过对测量后的图像进行量化处理后再进行加密操作得到密文图像。实验结果表明,所提算法能够实现对CT图像、MRI图像、B超图像以及X光图像等医学图像的压缩和加密,在能够有效实现数据量减少的同时具有良好的加密性能。在与均匀量化函数及Sigmoid量化函数不同压缩比的比较中,采用Tanh量化函数的重构图像具有更稳定的峰值信噪比变化。同时,所提算法能抵御剪切攻击和噪声攻击,表现出较好的鲁棒性。A medical image compression and encryption algorithm based on synchronous chaotic stream cipher and two-dimensional compressive sensing is proposed.Firstly,a discrete wavelet transform is used to transform plaintext image into sparse image.Then,the synchronous chaotic stream cipher system is iterated to produce three chaotic sequences.In which,two chaotic sequences are used to construct two measurement matrices for compressive sensing.And the third chaotic sequence is used to construct pseudo-random sequence for encryption.Finally,the cipher image is obtained by quantizing the measured image and then encrypting it.The experimental results show that the proposed algorithm can realize the compression and encryption of medical images such as CT images,MRI images,B-ultrasonic images and X-Ray images.It shows good encryption performance while effectively reducing the data sizes.By compared with Uniform quantization function and Sigmoid quantization function in different compression ratios,the reconstructed image using Tanh quantization function has more stable changes in peak signal to noise ratio.Meanwhile,the proposed algorithm can resist shear attack and noise attack,showing good robustness.

关 键 词：压缩感知 同步混沌流密码 Tanh量化函数 医学图像加密 

分 类 号：R318[医药卫生—生物医学工程] TP309.7[医药卫生—基础医学] O415.5[自动化与计算机技术—计算机系统结构]