一种不完全投影图像重建的快速迭代算法  

Fast iterative algorithm for image reconstruction from incomplete projections

作　　者：高欣[1] 夏顺仁[2] 汪元美[2] 罗戎蕾[2] 

机构地区：[1]浙江大学CAD&CG国家重点实验室,浙江杭州310027 [2]浙江大学生物医学工程教育部重点实验室,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2004年第9期1108-1111,共4页Journal of Zhejiang University：Engineering Science

基　　金：国家"863"高技术研究发展计划资助项目(2002AA135050).

摘　　要：为了保证不完全投影数据的重建图像质量,同时提高重建速度,提出了一种基于共轭梯度法的快速迭代算法.通过实时获取投影矩阵分量,以固定步长替代共轭梯度法中一维搜索最优迭代步长,在确保质量的同时缩短重建时间.利用模拟投影数据和实际导弹断层扫描数据进行图像重建,结果表明,与卷积反投影和代数重建法相比,此算法特别适用于扇形扫描的不完全投影数据的图像重建,在保证重建图像拟合度的同时,大大提高了重建速度.A novel fast iterative algorithm for imaging reconstruction based on conjugate gradient technique was present. The real-time obtainment of the components of projection matrix and the substitution of constant step for optimal step in the one-dimension search in conjugate gradient were adopted to ensure the quality of reconstructed image from incomplete projections and shorten the reconstruction time simultaneously. The experimental results of reconstruction from computer-generated projections and real missile tomography projections show that the fast algorithm guarantees the fitness to original image, speeds the iteration time, and can be specially used for reconstruction for incomplete projections in fan scanning.

关 键 词：不完全投影图像 图像重建 快速迭代算法 扇形扫描 共轭梯度法 最速下降法 

分 类 号：TN911.73[电子电信—通信与信息系统]