基于Shepp-Logan头模型的锥束CT仿真投影快速计算  

Fast Calculation of Simulation Projection for Cone-beam CT Based on Shepp-Logan Head Phantom

作　　者：张顺利[1,2] 张定华[1] 李小林[2] 刘敏娜[2] 

机构地区：[1]西北工业大学现代设计与集成制造技术教育部重点实验室,西安710072 [2]咸阳师范学院图形图像处理研究所,咸阳712000

出　　处：《计算机科学》2012年第5期257-260,共4页Computer Science

基　　金：中国博士后科学基金项目(20110491690);陕西省教育厅专项基金(11JK1030);咸阳师范学院引进人才项目(10XSYK102;09XSYK206)资助

摘　　要：针对三维Shepp-Logan头模型投影仿真,提出了一种快速并行投影计算方法。首先依次计算三维射线与各椭球的交点,然后对交点序列进行排序,用排序后的交点序列来确定射线穿过模型的区域编号及长度,最后将每个区域内的投影累加得到射线的投影值。在此基础上,将计算任务分解为4个独立的子任务,通过多线程技术在多核平台上实现了锥束CT仿真投影的快速并行计算。实验结果表明,该方法非常有效,在四核平台上取得了约3.5倍的加速比;图像重建结果验证了该方法生成的投影数据是准确的。Aiming at the problem of projection simulation of 3D Shepp-Logan head phantom,this paper proposed a fast parallel method to calculate simulation projection.Firstly,the intersection points of 3D ray and each ellipsoid were calculated in turn.Then,the sequence of intersection points was sorted,by which the region number of phantom and length of intersection between the ray and the region were determined.Finally,the projection of the ray was obtained by summing the projection of each region.On this basis,we decomposed the computing task into four independent subtasks and rea-lized fast parallel calculation of simulation projection of cone-beam CT on multi-core platform by multi-thread technique.Experimental result shows that the proposed method is very effective,can get a speedup about 3.5 times on quad cores platform.The accuracy of the projection data generated by the proposed method was verified by results of image reconstruction.

关 键 词：锥束CT Shepp-Logan头模型 投影仿真 多线程 图像重建 

分 类 号：TP391[自动化与计算机技术—计算机应用技术]