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Related papers: Multigrid methods for total variation

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Pretrained segmentation models for cardiac magnetic resonance imaging (MRI) struggle to generalize across different imaging sequences due to significant variations in image contrast. These variations arise from changes in imaging protocols,…

Computer Vision and Pattern Recognition · Computer Science 2025-09-01 Yidong Zhao , Peter Kellman , Hui Xue , Tongyun Yang , Yi Zhang , Yuchi Han , Orlando Simonetti , Qian Tao

Super-resolution fluorescence microscopy overcomes blurring arising from light diffraction, allowing the reconstruction of fine scale details in biological structures. Standard methods come at the expense of long acquisition time and/or…

Optimization and Control · Mathematics 2021-10-12 Bastien Laville , Laure Blanc-Féraud , Gilles Aubert

We design and analyze an iterative two-grid algorithm for the finite element discretizations of strongly nonlinear elliptic boundary value problems in this paper. We propose an iterative two-grid algorithm, in which a nonlinear problem is…

Numerical Analysis · Mathematics 2023-05-04 Jiajun Zhan , Lei Yang , Xiaoqing Xing , Liuqiang Zhong

We present a novel approach to denoising and inpainting problems for surface meshes. The purpose of these problems is to remove noise or fill in missing parts while preserving important features such as sharp edges. A discrete variant of…

Numerical Analysis · Mathematics 2025-02-03 Lukas Baumgärtner , Ronny Bergmann , Roland Herzog , Stephan Schmidt , José Vidal-Núñez , Manuel Weiß

This paper focuses on the development of a space-variant regularization model for solving an under-determined linear inverse problem. The case study is a medical image reconstruction from few-view tomographic noisy data. The primary…

Image and Video Processing · Electrical Eng. & Systems 2024-04-29 Elena Morotti , Davide Evangelista , Andrea Sebastiani , Elena Loli Piccolomini

Total variation (TV) is a widely used regularizer for stabilizing the solution of ill-posed inverse problems. In this paper, we propose a novel proximal-gradient algorithm for minimizing TV regularized least-squares cost functional. Our…

Information Theory · Computer Science 2016-01-05 Ulugbek S. Kamilov

Total variation (TV) is a powerful regularization method that has been widely applied in different imaging applications, but is difficult to apply to diffuse optical tomography (DOT) image reconstruction (inverse problem) due to complex and…

Computer Vision and Pattern Recognition · Computer Science 2019-04-08 Wenqi Lu , Jinming Duan , David Orive-Miguel , Lionel Herve , Iain B Styles

Several recent works have explored stochastic gradient methods for variational inference that exploit the geometry of the variational-parameter space. However, the theoretical properties of these methods are not well-understood and these…

Machine Learning · Statistics 2016-08-15 Mohammad Emtiyaz Khan , Reza Babanezhad , Wu Lin , Mark Schmidt , Masashi Sugiyama

This paper presents a generative model for super-resolution in routine clinical magnetic resonance images (MRI), of arbitrary orientation and contrast. The model recasts the recovery of high resolution images as an inverse problem, in which…

Computer Vision and Pattern Recognition · Computer Science 2019-09-10 Mikael Brudfors , Yael Balbastre , Parashkev Nachev , John Ashburner

The total variation (TV) method is an image denoising technique that aims to reduce noise by minimizing the total variation of the image, which measures the variation in pixel intensities. The TV method has been widely applied in image…

Computer Vision and Pattern Recognition · Computer Science 2024-10-04 Jing-En Huang , Jia-Wei Liao , Ku-Te Lin , Yu-Ju Tsai , Mei-Heng Yueh

The problem of restoration of digital images from their degraded measurements plays a central role in a multitude of practically important applications. A particularly challenging instance of this problem occurs in the case when the…

Computer Vision and Pattern Recognition · Computer Science 2016-11-17 Oleg Michailovich

Denoising is of utmost importance for the visualization and processing of images featuring low signal-to-noise ratio. Total variation methods are among the most popular techniques to perform this task improving the signal-to-noise ratio…

Signal Processing · Electrical Eng. & Systems 2022-01-24 Gonzalo D. Maso Talou , Pablo J. Blanco

To overcome the weakness of a total variation based model for image restoration, various high order (typically second order) regularization models have been proposed and studied recently. In this paper we analyze and test a fractional-order…

Computer Vision and Pattern Recognition · Computer Science 2015-09-15 Jianping Zhang , Ke Chen

We present an effective method for the matching of multimodal images. Accurate image matching is the basis of various applications, such as image registration and structure from motion. Conventional matching methods fail when handling noisy…

Computer Vision and Pattern Recognition · Computer Science 2023-03-01 Zhongli Fan , Li Zhang , Yuxuan Liu

Due to the high computational load of modern numerical simulation, there is a demand for approaches that would reduce the size of discrete problems while keeping the accuracy reasonable. In this work, we present an original algorithm to…

Machine Learning · Computer Science 2025-07-25 Sergei Shumilin , Alexander Ryabov , Nikolay Yavich , Evgeny Burnaev , Vladimir Vanovskiy

Image inverse problems have numerous applications, including image processing, super-resolution, and computer vision, which are important areas in image science. These application models can be seen as a three-function composite…

Computer Vision and Pattern Recognition · Computer Science 2024-12-12 Yunfei Qu , Deren Han

The use of multigrid and related preconditioners with the finite element method is often limited by the difficulty of applying the algorithm effectively to a problem, especially when the domain has a complex shape or adaptive refinement. We…

Numerical Analysis · Computer Science 2015-03-19 Peter R. Brune , Matthew G. Knepley , L. Ridgway Scott

We introduce a new non-smooth variational model for the restoration of manifold-valued data which includes second order differences in the regularization term. While such models were successfully applied for real-valued images, we introduce…

Numerical Analysis · Mathematics 2018-12-10 Miroslav Bačák , Ronny Bergmann , Gabriele Steidl , Andreas Weinmann

The variation procedure on a teleparallel manifold is studied. The main problem is the non-commutativity of the variation with the Hodge dual map. We establish certain useful formulas for variations and restate the master formula due to…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Yakov Itin

We develop a geometric version of the inverse problem of the calculus of variations for discrete mechanics and constrained discrete mechanics. The geometric approach consists of using suitable Lagrangian and isotropic submanifolds. We also…

Differential Geometry · Mathematics 2018-05-09 María Barbero-Liñán , Marta Farré Puiggalí , Sebastián Ferraro , David Martín de Diego