https://scholars.lib.ntu.edu.tw/handle/123456789/625453
標題: | Fast implementation of the incremental backprojection algorithms for parallel beam geometries | 作者: | CHUNG-MING CHEN Cho Zang-Hee Wang Cheng-Yi |
公開日期: | 1995 | 卷: | 2 | 起(迄)頁: | 1277-1281 | 來源出版物: | IEEE Nuclear Science Symposium & Medical Imaging Conference | 摘要: | The Incremental backprojection algorithm is a fast backprojection approach requiring only O(N) and O (N2) multiplications in contrast to O(N2) and O(N3) multiplications for the Shepp and Logan's backprojection algorithm in 2D and 3D backprojections, respectively, for each view. However, the improvement achieved by the Incremental algorithm in practice was not so significant as expected in theory due to inevitably visiting pixels outside the beam in the searching flow scheme originally developed for the Incremental algorithm. To optimize implementation of the Incremental algorithm, an efficient scheme, namely, coded searching flow scheme, is proposed in this paper to minimize the overhead caused by searching for all pixels in a beam. The key idea of this scheme is to encode the searching flow for all pixels inside each beam. While backprojection, all pixels may be visited without any overhead due to using the coded searching flow as the a priori information. The proposed coded searching flow scheme has been implemented on a Sun Sparc 10 and a Sun Sparc 20 workstations. The implementation results show that the proposed scheme is 1.45-2.0 times faster than the original searching flow scheme for most cases tested. Compared to the conventional Shepp and Logan's backprojection algorithm, the proposed scheme may achieve 5-8 and 3 times speed-ups for 2D and 3D backprojection, respectively. |
URI: | https://www.scopus.com/inward/record.uri?eid=2-s2.0-0029464189&partnerID=40&md5=a9bffcdfe936545fb02ceb0c7c444511 https://scholars.lib.ntu.edu.tw/handle/123456789/625453 |
SDG/關鍵字: | Computational geometry; Computer workstations; Image coding; Image reconstruction; Optimization; Coded searching flow scheme; Incremental backprojection algorithms; Parallel beam geometries; Algorithms |
顯示於: | 醫學工程學研究所 |
在 IR 系統中的文件,除了特別指名其著作權條款之外,均受到著作權保護,並且保留所有的權利。