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Cone-beam reconstruction by backprojection and filtering.

A V Bronnikov
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Abstract

A new analytical method for tomographic image reconstruction from cone-beam projections acquired on the source orbits lying on a cylinder is presented. By application of a weighted cone-beam backprojection, the reconstruction problem is reduced to an image-restoration problem characterized by a shift-variant point-spread function that is given analytically. Assuming that the source is relatively far from the imaged object, a formula for an approximate shift-invariant inverse filter is derived; the filter is presented in the Fourier domain. Results of numerical experiments with circular and helical orbits are considered.

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A V Bronnikov. 2000. Cone-beam reconstruction by backprojection and filtering.. https://doi.org/10.1364/josaa.17.001993

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