一种圆轨迹锥束CT中截断投影数据的高效重建算法  

Efficient reconstruction from truncated data in circular cone-beam CT

作　　者：汪先超[1] 闫镔[1] 刘宏奎[2] 李磊[1] 魏星[1] 胡国恩[1] 

机构地区：[1]国家数字交换系统工程技术研究中心,郑州450002 [2]大连理工大学建设工程学院,大连116000

出　　处：《物理学报》2013年第9期493-499,共7页Acta Physica Sinica

基　　金：国家高技术研究发展计划批准号资助的课题~~

摘　　要：本文基于数据重排方法,提出了T-BPF(Tent-BPF)算法,该算法先将锥束投影数据重排成平行投影数据,然后使用一种推导的BPF型算法重建重排后的平行投影数据.T-BPF算法将原BPF算法反投影中变化的角度积分限变成固定的,反投影中各层循环之间没有了相关性,这意味着T-BPF算法较原BPF算法具有更好的可并行性.实验结果显示:使用GPU对2563的Shepp-Logan体模的图像重建进行并行加速,T-BPF算法在保证重建质量的前提下,加速比达到了1036,较原BPF算法有很大提升.T-BPF算法为截断投影数据的3D图像快速重建提供了方法.In circular cone-beam computed tomography （CT）, to solve the 3D image reconstruction from truncated projection data which has no truncation along PI-line, backprojection-filtration （BPF） algorithm is a preferred choice. However, in its performance the integral interval of backprojection is variable for different PI-line, rendering the parallelism performance of backprojection low. So it cannot satisfy the requirement of fast image reconstruction in practical CT system. In this paper, a tent BPF （T-BPF） algorithm is developed based on the data rebinning method, which was performed by first rearranging the cone-beam data to tent-like parallel-beam data, and then applying the proposed BPF-type algorithm to reconstruct images from the rearranged data. T-BPF turns the variable view-angle integral interval of backprojection into a fixed integral interval, and there are no relations in the loops of backprojection calculation, which means the parallelism performance of T-BPF is an improvement over that of the original BPF algorithm. The results of experiments show that compared with the conventional CPU implementation, the GPU accelerated method provides images of the same quality with a speedup factor 1036 for the reconstruction of 256 3 Shepp-Logan model. The speedup factor is an improvement in the original BPF algorithm. T-BPF provides a solution for the 3D fast reconstruction from truncated data.

关 键 词：X射线光学 CT 图像重建 GPU 

分 类 号：TP391.41[自动化与计算机技术—计算机应用技术]