207	1998	David Gottlieb and Bertil Gustafsson	bertil@tdb.uu.se	On the Direct Fourier Method for Computer Tomography

                      Abstract

The paper considers the Direct Fourier Methods for reconstructing an
image from its given X-ray projections. The main purpose here is to
use concepts from numerical analysis to estimate the errors in the
methods. We also suggest an alternative way to the interpolations
involved in the Direct Fourier Methods and estimate the number of terms
involved.  Realizing that one of the main reasons for the degradation
of the quality of the reconstruction is the Gibbs phenomenon, we
suggest a way to overcome this difficulty and give numerical evidence
to its efficacy.