顺序小波包图像压缩感知方法  

Sequential Image Compressed Sensing Based on Wavelet Packet

作　　者：周四望[1] 罗孟儒[1] 

机构地区：[1]湖南大学信息科学与工程学院,湖南长沙410082

出　　处：《湖南大学学报（自然科学版）》2015年第4期130-135,共6页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(60973127);教育部新世纪优秀人才计划基金资助课题(NCET-11-0136);湖南省自然科学基金资助项目(14JJ2051)~~

摘　　要：针对压缩感知中测量次数不确定的问题,提出了顺序小波包图像压缩感知方法.该方法选用小波包变换分解图像,降低信号稀疏度,将图像划分为大小相等的小波包系数块,利用小波包系数块数学期望与稀疏度之间的关系,对初始采样信号y0的长度进行预测;同时变长设置顺序压缩感知过程中采样信号y1,…,yn的长度,来减少解压缩端重构次数以及两端的通信次数,从而解决传统顺序压缩感知方法中存在的不足.实验表明该方法在重构次数和重构精度上优于传统顺序压缩感知方法.Aiming at solving the problem of the times of measurements, a scheme of sequential com- pressed sensing based on wavelet packet was proposed. The wavelet packet transform was firstly employed and the image was decomposed into wavelet packet blocks with the same size. The length of the initial sampling signal was then estimated using the relationship between the mathematical expectation and the sparsity of wavelet packet blocks. Meanwhile, the lengths of sampling signals were set dynamically in or- der to reduce the reconstruction and communication overhead. The problem of uncertain times of measure- ments in the traditional compressed sensing was thus overcome. Experimental results show that our pro- posed scheme has less reconstruction times and lower reconstruction error than the existed ones.

关 键 词：小波变换 压缩感知 数学期望 图像 

分 类 号：TN911.73[电子电信—通信与信息系统]