基于一维压缩感知和混沌的医学图像加密研究

Medical Image Encryption Based on 1D Compressed Sensing and Chaos

医学图像由于涉及隐私等重要问题,其安全性问题逐渐凸显,同时其具有数据量大、同色像素连续性高等特点。为实现医学图像安全、快速地在网络中传输,提出一种基于压缩感知和同步混沌流密码的医学图像加密方案。首先迭代三维同步混沌流密码系统构造出测量矩阵和得到用于加密的伪随机序列。然后,利用测量矩阵对整数小波变换后的稀疏医学图像进行测量,并使用量化函数将测量后的图像量化至[0,255]范围内的整数。最后,利用伪随机序列加密量化后的图像。相应的解密算法也同时给出。从以CT图像为例的实验仿真结果可知,该方案具有良好的压缩和加密性能。同时,相关安全性能分析结果表明,所提方案对统计攻击和剪切攻击具有良好的安全性和鲁棒性。

In order to realize the secure and fast transmission of medical image in the network,this paper proposes a medical image encryption scheme based on compressed sensing(CS)and synchronous chaotic stream cryptography.Firstly,by iterating the three-dimensional synchronous chaotic stream cipher system,the measurement matrix is constructed and the pseudo-random sequence used for encryption is obtained.Then,the measurement matrix is used to measure the sparse medical image after integer wavelet transformation(IWT),and the quantization function is used to quantize the measured image to an integer within the range[0,255].Finally,pseudo-random sequences are used to encrypt the quantized images.The corresponding decryption algorithm is also given.The simulation results of CT images show that the scheme has good compression and encryption performances.