燕山大学学报2015，Vol.39Issue(4)：366-372,7.DOI:10.39+9/j.issn.1007-791X.2015.04.014
基于变步长子空间追踪的DCT域非均匀采样图像重构
Non-uniform sampling imagr rrconstruction basrd on variablr strp-sizr subspacr pursuit in DCT domain
摘要
Abstract
Compressive sensing is a novel sampling theory that takes full advantage of the signal′s sparsity. A key research subject in it is how to recover the original high-dimensional data from the low-dimensional compressed data. Non-uniform sampling is stud-ied in this paper, based on the distribution character of image Discrete Cosine Transform ( DCT) coefficients. Moreover, a new Subspace Pursuit (SP) algorithm with variable step-sizes in DCT domain is proposed, to reconstruct the compressed images fast and accurately. This algorithm sets the sampling rates of columns in DCT coefficient matrix adaptively, so that more samples are as-signed to the columns with more high-magnitude coefficients. When reconstructing the columns of DCT coefficients, this algorithm adjusts the support search step-sizes used in different subspaces dynamically. In the atom subsets which correspond to the coeffi-cients with high amplitudes, small step-sizes are preferred. On the contrary, large step-sizes are preferred. Simulation results show that the proposed algorithm prevails over the original DCT-domain SP algorithm both on image reconstruction accuracy and on the reconstruction runtime.关键词
压缩感知/图像重构/子空间追踪/非均匀采样/变步长Key words
compressive sensing/image reconstruction/subspace pursuit/non-uniform sampling/variable step-size分类
信息技术与安全科学引用本文复制引用
司菁菁,乔新凤,程银波..基于变步长子空间追踪的DCT域非均匀采样图像重构[J].燕山大学学报,2015,39(4):366-372,7.基金项目
国家自然科学基金资助项目(61471313, 61303128 ) （61471313, 61303128 ）
河北省自然科学基金资助项目(F201403183) （F201403183）
河北省高等学校科学技术研究项目(Q2012087) （Q2012087）
燕山大学青年教师自主研究计划课题(13LGB015) （13LGB015）
