Egger M L, Joseph C, Morel C
Institute of Nuclear Physics, University of Lausanne, Switzerland.
Phys Med Biol. 1998 Oct;43(10):3009-24. doi: 10.1088/0031-9155/43/10/023.
Cho et al have proposed a fast backprojection scheme for parallel beam geometries, the incremental algorithm, which performs backprojection on a ray-by-ray (beam-by-beam) basis as opposed to a pixel-by-pixel approach. We present an extension of this incremental, beamwise, backprojection algorithm to the case of volume reconstruction of data acquired by a cylindrical, multiring positron tomograph. Use is made of geometrical symmetries of the image volume. This method results in a twelve-fold reduction of execution time compared with a straightforward, voxel-driven implementation of the same interpolation equations.
赵等人提出了一种用于平行光束几何结构的快速反投影方案，即增量算法，该算法逐射线（逐光束）进行反投影，而不是逐像素方法。我们将这种增量式逐光束反投影算法扩展到通过圆柱形多环正电子断层扫描仪采集的数据的体素重建情况。利用了图像体素的几何对称性。与直接的、体素驱动的相同插值方程实现相比，该方法的执行时间减少了12倍。
