Ordered Subset Expectation Maximum Algorithms Based on Symmetric Structure for Image Reconstruction

Symmetry

Chang Liu¹  Jun Qiu¹ 

[1] Institute of Applied Mathematics, Beijing Information Science and Technology University, Beijing 100101, China;

关键词: image reconstruction;    symmetry structure;    expectation maximization;    ordered subset;    discretization model;   

DOI  :  10.3390/sym10100449

来源: DOAJ

【 摘 要 】

In this paper, we propose the symmetric structure of the reconstructed points discretization model to partition and order the subsets of Ordered Subset Expectation Maximum (OSEM) algorithms for image reconstruction and then simplify the calculation of the projection coefficient matrix while satisfying the balancing properties of subsets. The reconstructed points discretization model was utilized to describe the forward and inverse relationships between the reconstructed points and the projection data according to the distance from the point to the ray rather than the intersection length between the square pixel and the ray. This discretization model provides new approaches for improving and constructing the reconstruction algorithms on the basis of the geometry of the model. The experimental results show that the OSEM algorithms based on the reconstructed points discretization model and its geometric symmetry structure can effectively improve the imaging speed and the imaging precision.

【 授权许可】

Unknown