基于图形处理器的并行加速双能计算机层析成像重建方法

Parallel Accelerated Reconstruction Method for Dual-Energy Computed Tomography Based on Graphics Processing Unit

提出了一种基于图形处理器(GPU)并行加速双能计算机层析成像(CT)重建的整体解决方法.该方法通过将双能采样数据视角配准步骤整合到基本的双能CT重建过程中,保证了双能投影分解的准确性,从而提高了双能CT重建的准确性.通过在反投影步骤中同时反投影几种图像,避免重复计算投影地址,并且在整体重建过程的各个步骤中采用GPU并行方式进行计算,有效提高了双能CT的重建速度.重建图像为2种和4种时,与重复执行多次单能CT并行重建相比,本文方法的重建过程加速比分别为1.88和3.24,其中最耗时反投影步骤加速比分别为1.90和3.66.实验和实际应用证明了该方法可有效提高双能CT重建的准确性和速度.

A complete solution for parallel accelerated reconstruction of dual-energy computed tomography(CT)based on graphics processing unit(GPU)is proposed.By integrating the view angle registration steps of dual-energy sampling data into the basic reconstruction process of dual-energy CT,the accuracy of dual-energy projection decomposition is granted,and the accuracy of dual-energy CT reconstruction is improved.Several images are back-projected simultaneously in the back-projection step to avoid repeated calculation of projection addresses,and GPU parallel algorithm is used in each step in the whole reconstruction process to improve the reconstruction speed of dual-energy CT.When the reconstructed images are two and four types,compared with the reconstruction speed of repeated reconstruction by single-energy CT,the speedup ratio of the reconstruction process of the proposed method is 1.88 and 3.24,respectively,and the speedup ratio of the most time-consuming back-projection step is 1.90 and 3.66,respectively.Experiments and practical application prove that the proposed method can effectively improve the accuracy and speed of dual-energy CT reconstruction.