Reconstruction of Voxels with Position- and Angle-Dependent Weightings

• URL: http://arxiv.org/abs/2010.14205v1
• Date: Tue, 27 Oct 2020 11:29:47 GMT
• Title: Reconstruction of Voxels with Position- and Angle-Dependent Weightings
• Authors: Lina Felsner, Tobias W\"urfl, Christopher Syben, Philipp Roser, Alexander Preuhs, Andreas Maier, and Christian Riess
• Abstract summary: 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.
• Score: 66.25540976151842
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• 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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