| 摘要 |
Methods for improving the processing time, scalability, and resource usage for three-dimensional projecting-backprojecting rays with respect to voxels (pixels) and detector bins are provided. Specifically, improvements to a distance-driven technique, wherein the pixels and detector edges are projected on to a predetermined reference plane are disclosed. The methods balance the computational load of a system of parallel processors, which results in a balanced memory and cache access operations, while reducing the computational complexity of projection-backprojection techniques in scanning systems. |
| 主权项 |
1. A method of reducing computation time in distance-driven reprojection from an image space having a plurality of pixels for a scanning system, the scanning system including a detector having a plurality of detector elements, the method comprising:
determining, for a given view and for each detector element of the plurality of detector elements, a projection location of each edge of the detector element onto a predetermined reference axis; determining, for the given view and for each pixel of the plurality of pixels, a projection location of each edge of the pixel onto the predetermined axis; identifying, for each detector element, contributing pixels having corresponding pixel values that contribute to a detector value of the detector element, based on the projection location of each edge of the detector element and the projection location of each edge of the plurality of pixels; scheduling parallel computations for the detector elements in each processing cycle of the scanning system, based on a number of processors included in the scanning system; and calculating, based on the scheduled parallel computations, the detector value of each detector element as a sum, over the total number of contributing pixels, of the corresponding pixel values of the contributing pixels, each pixel value being weighted by a corresponding weight. |
