数字合成X射线体层成像的小波-伽辽金重建算法  

Image Reconstruction in Tomosynthesis by Wavelet Galerkin Method

作　　者：卢孝强[1] 白刚锋[1] 孙怡[1] 

机构地区：[1]大连理工大学电子与信息工程学院,辽宁大连116023

出　　处：《CT理论与应用研究（中英文）》2010年第3期13-23,共11页Computerized Tomography Theory and Applications

基　　金：教育部科学技术研究重点项目(教技司计[2007]2号);国家自然科学基金(60572110);辽宁省优秀人才基金

摘　　要：数字合成X射线体层成像技术的重建问题是在有限投影数据条件下的病态重建问题。本文通过分析数字合成X射线体层成像技术的系统模型,获得重建问题的系统方程。在对系统方程进行正则化改造的基础上,提出了一种新的重建算法——自适应小波-伽辽金重建算法。该算法融合了伽辽金方法的计算简洁和小波内在的多尺度特性,更好地适应了待重建图像的求解。仿真实验结果表明,与ART重建算法相比,自适应小波-伽辽金重建算法在保证重建质量前提下能加快收敛,从而大大地节省了计算时间。In tomosynthesis,projection data are acquired from limited view angles,which is a severely ill-posed inverse problem.Based on the model of tomosynthesis,the system equation is presented.After regularizating the system equation,an adaptive wavelet Galerkin method is proposed to reconstruct images in tomosynthesis.The method combined the numerical simplicity of Galerkin method with the inherent scale multiplicity characteristic of wavelet which is more adaptable to the resolution of the reconstructed image.Compared to the ART reconstruction,the results demonstrate that the reconstruction strategy has comparable performance with the improvement of the convergence speed and the reduction of computational time.

关 键 词：X射线光学 数字合成X射线体层成像 图像重建 小波-伽辽金 正则化 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]