THE USE OF ENTROPIC THRESHOLDING METHODS IN RECONSTRUCTION OF CAPACITANCE TOMOGRAPHY DATA

High-quality reconstruction of capacitance tomography data is of vital importance to ensure quantitative information from such systems. Seve ral methods have been tested, such as linear back projection (LBP), re presenting a fast and crude method, and model-based reconstruction (MO R) which significantly improves the results, although at higher comput ational cost. The main problem of using LBP is the smoothing effect on sharp transitions in the dielectric constant distribution. The recons truction quality could be improved by including a thresholding procedu re in the reconstruction process; In this work, entropic thresholding methods are used. These methods are compared to previously published t hresholding techniques such as Xie's method and an implicit model-base d reconstruction method. A computer simulated eight-electrode capacita nce tomography system has been used for the evaluation. (C) 1997 Elsev ier Science Ltd. All rights reserved.