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arXiv · 2010.14205

Reconstruction of Voxels with Position- and Angle-Dependent Weightings

Lina Felsner·Tobias Würfl·Christopher Syben·Philipp Roser·Alexander Preuhs·Andreas Maier·Christian Riess
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Abstract

The reconstruction problem of voxels with individual weightings can be modeled a position- and angle- dependent function in the forward-projection. This changes the system matrix and prohibits to use standard filtered backprojection. In this work we first formulate this reconstruction problem in terms of a system matrix and weighting part. We compute the pseudoinverse and show that the solution is rank-deficient and hence very ill posed. This is a fundamental limitation for reconstruction. We then derive an iterative solution and experimentally show its uperiority to any closed-form solution.

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Lina Felsner, Tobias Würfl, Christopher Syben, Philipp Roser, Alexander Preuhs, Andreas Maier, Christian Riess. 2020-10-27. Reconstruction of Voxels with Position- and Angle-Dependent Weightings. https://arxiv.org/abs/2010.14205

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