Efficient Bandwidth Estimation in 2D Filtered Backprojection Reconstruction

• NCJ Number: 302721
• Author(s): R. Maitra
• Date Published: 2019
• Grant Number(s): 2015-DN-BX-K056; 2018-R2-CX-0034
• Agencies: NIJ-Sponsored
• Award: Quantitative Tools for Examination of Microscopic Fracture Surface Topology and Degradation for Physical Match Analysis of Evidence; Physics and Statistical Models for Physical Match Analysis Utilizing 3D Microscopy of Fracture Surfaces

Annotation

A generalized cross-validation approach to estimate the reconstruction filter bandwidth in 2D filtered backprojection is presented. 

Abstract

The method writes the reconstruction equation in equivalent backprojected filtering form, derives results on eigendecomposition of symmetric 2D circulant matrices, and applies them to make bandwidth estimation a computationally efficient operation within the context of standard backprojected filtering reconstruction. Performance evaluations on a range of simulated emission tomography experiments give promising results. The superior performance holds at both low and high total expected counts, pointing to the method's applicability even in weak signal-to-noise-ratio situations. The approach also applies to the more general class of elliptically symmetric filters, with the reconstructed estimate's performance often better than even that obtained with the true optimal radially symmetric filter. 4 figures (publisher abstract modified)