摘要
Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multiorientation Simultaneous Back Projection (MSBP) approach is proposed in this papar for two-dimensional (2-D) parallel and fan beam CT systems. In this scheme, backprojections for eight views, 6, π/2 - θ, π/2 + 6, π- θ, π+ θ, 3π/2 - θ, 3π/2 + θ, and 2π- θ, are implemented at the same time,while the locating operation of pixels for interpolation and computation of weighting parameters are only required for one of them when one half of the number of thaws is even. Implementation remits on an Intel 80386 hosed computer show that the proposed method has a notable computational gain,compared with the conventional implementation of backprojection.
Based on the geometrical relationships between image pixels and projection rays at different viewing angles,a Multiorientation Simultaneous Back Projection (MSBP) approach is proposed in this papar for two-dimensional (2-D) parallel and fan beam CT systems. In this scheme, backprojections for eight views, 6, π/2 - θ, π/2 + 6, π- θ, π+ θ, 3π/2 - θ, 3π/2 + θ, and 2π- θ, are implemented at the same time,while the locating operation of pixels for interpolation and computation of weighting parameters are only required for one of them when one half of the number of thaws is even. Implementation remits on an Intel 80386 hosed computer show that the proposed method has a notable computational gain,compared with the conventional implementation of backprojection.
