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arXiv · 2309.06948

Limited-Angle Tomography Reconstruction via Deep End-To-End Learning on Synthetic Data

Thomas Germer·Jan Robine·Sebastian Konietzny·Stefan Harmeling·Tobias Uelwer
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Abstract

Computed tomography (CT) has become an essential part of modern science and medicine. A CT scanner consists of an X-ray source that is spun around an object of interest. On the opposite end of the X-ray source, a detector captures X-rays that are not absorbed by the object. The reconstruction of an image is a linear inverse problem, which is usually solved by filtered back projection. However, when the number of measurements is small, the reconstruction problem is ill-posed. This is for example the case when the X-ray source is not spun completely around the object, but rather irradiates the object only from a limited angle. To tackle this problem, we present a deep neural network that is trained on a large amount of carefully-crafted synthetic data and can perform limited-angle tomography reconstruction even for only 30{\deg} or 40{\deg} sinograms. With our approach we won the first place in the Helsinki Tomography Challenge 2022.

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Thomas Germer, Jan Robine, Sebastian Konietzny, Stefan Harmeling, Tobias Uelwer. 2023-09-13. Limited-Angle Tomography Reconstruction via Deep End-To-End Learning on Synthetic Data. https://arxiv.org/abs/2309.06948

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