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20062024
most citedSparse Regularization with Penalty Term

180 citations · 1.3k across the 95 of their papers we have counts for

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Showing 2019Show all

14 papers · 1 filter

cs.CV2019★ 19 cited

Random 2.5D U-net for Fully 3D Segmentation

Christoph Angermann, Markus Haltmeier

Convolutional neural networks are state-of-the-art for various segmentation tasks. While for 2D images these networks are also computationally efficient, 3D convolutions have huge…

math.NA2019

Sparse regularization of inverse problems by operator-adapted frame thresholding

Jürgen Frikel, Markus Haltmeier

We analyze sparse frame based regularization of inverse problems by means of a diagonal frame decomposition (DFD) for the forward operator, which generalizes the SVD. The DFD allow…

math.NA2019

Augmented NETT Regularization of Inverse Problems

Daniel Obmann, Linh Nguyen, Johannes Schwab +1

We propose aNETT (augmented NETwork Tikhonov) regularization as a novel data-driven reconstruction framework for solving inverse problems. An encoder-decoder type network defines a…

eess.IV2019★ 1 cited

Learned backprojection for sparse and limited view photoacoustic tomography

Johannes Schwab, Stephan Antholzer, Markus Haltmeier

Filtered backprojection (FBP) is an efficient and popular class of tomographic image reconstruction methods. In photoacoustic tomography, these algorithms are based on theoreticall…

math.AP2019

Explicit inversion formulas for the two-dimensional wave equation from Neumann traces

Florian Dreier, Markus Haltmeier

In this article we study the problem of recovering the initial data of the two-dimensional wave equation from Neumann measurements on a convex domain with smooth boundary in the pl…

cs.CV2019

A Joint Deep Learning Approach for Automated Liver and Tumor Segmentation

Nadja Gruber, Stephan Antholzer, Werner Jaschke +2

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults, and the most common cause of death of people suffering from cirrhosis. The segmentation of…

math.NA2019

Analysis of the Block Coordinate Descent Method for Linear Ill-Posed Problems

Simon Rabanser, Lukas Neumann, Markus Haltmeier

Block coordinate descent (BCD) methods approach optimization problems by performing gradient steps along alternating subgroups of coordinates. This is in contrast to full gradient…

math.NA2019

Sparse synthesis regularization with deep neural networks

Daniel Obmann, Johannes Schwab, Markus Haltmeier

We propose a sparse reconstruction framework for solving inverse problems. Opposed to existing sparse regularization techniques that are based on frame representations, we train an…

cs.CV2019

Projection-Based 2.5D U-net Architecture for Fast Volumetric Segmentation

Christoph Angermann, Markus Haltmeier, Ruth Steiger +2

Convolutional neural networks are state-of-the-art for various segmentation tasks. While for 2D images these networks are also computationally efficient, 3D convolutions have huge…

math.NA2019★ 6 cited

NETT Regularization for Compressed Sensing Photoacoustic Tomography

Stephan Antholzer, Johannens Schwab, Johannes Bauer-Marschallinger +2

We discuss several methods for image reconstruction in compressed sensing photoacoustic tomography (CS-PAT). In particular, we apply the deep learning method of [H. Li, J. Schwab,…

math.NA2019★ 15 cited

Deep learning versus -minimization for compressed sensing photoacoustic tomography

Stephan Antholzer, Johannes Schwab, Markus Haltmeier

We investigate compressed sensing (CS) techniques for reducing the number of measurements in photoacoustic tomography (PAT). High resolution imaging from CS data requires particula…

math.NA2019★ 42 cited

Photoacoustic image reconstruction via deep learning

Stephan Antholzer, Johannes Schwab, Robert Nuster +1

Applying standard algorithms to sparse data problems in photoacoustic tomography (PAT) yields low-quality images containing severe under-sampling artifacts. To some extent, these a…

math.NA2019

Photoacoustic image reconstruction from full field data in heterogeneous media

Markus Haltmeier, Gerhard Zangerl, Robert Nuster +1

We consider image reconstruction in full-field photoacoustic tomography, where 2D projections of the full 3D acoustic pressure distribution at a given time T>0 are collected. We di…

math.NA2019

Deep Learning of truncated singular values for limited view photoacoustic tomography

Johannes Schwab, Stephan Antholzer, Robert Nuster +2

We develop a data-driven regularization method for the severely ill-posed problem of photoacoustic image reconstruction from limited view data. Our approach is based on the regular…