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Regularization-based image restoration has remained an active research topic in computer vision and image processing. It often leverages a guidance signal captured in different fields as an additional cue. In this work, we present a general…

Computer Vision and Pattern Recognition · Computer Science 2016-12-21 Youngjung Kim , Hyungjoo Jung , Dongbo Min , Kwanghoon Sohn

In digital images, the performance of optical aberration is a multivariate degradation, where the spectral of the scene, the lens imperfections, and the field of view together contribute to the results. Besides eliminating it at the…

Computer Vision and Pattern Recognition · Computer Science 2023-05-11 Shiqi Chen , Jinwen Zhou , Menghao Li , Yueting Chen , Tingting Jiang

Image restoration refers to the process of reconstructing noisy, destroyed, or missing parts of an image, which is an ill-posed inverse problem. A specific regularization term and image degradation are typically assumed to achieve…

Image and Video Processing · Electrical Eng. & Systems 2025-04-15 Jianwei Ke

Total Generalized Variation (TGV) regularization in image reconstruction relies on an infimal convolution type combination of generalized first- and second-order derivatives. This helps to avoid the staircasing effect of Total Variation…

Optimization and Control · Mathematics 2022-05-09 Michael Hintermüller , Kostas Papafitsoros , Carlos N. Rautenberg , Hongpeng Sun

Proper regularization is crucial in inverse problems to achieve high-quality reconstruction, even with an ill-conditioned measurement system. This is particularly true for three-dimensional photoacoustic tomography, which is computationally…

Optimization and Control · Mathematics 2024-09-26 Chao Wang , Alexandre H. Thiery

We study the qualitative properties of optimal regularisation parameters in variational models for image restoration. The parameters are solutions of bilevel optimisation problems with the image restoration problem as constraint. A general…

Optimization and Control · Mathematics 2020-02-13 Juan Carlos De Los Reyes , Carola-Bibiane Schönlieb , Tuomo Valkonen

Classical first-order optimization methods for imaging inverse problems scale poorly with image resolution. Wavelet based multilevel strategies can accelerate convergence under strong blur, but their fixed coarse-to-fine schedules lose…

Signal Processing · Electrical Eng. & Systems 2026-03-03 Edgar Desainte-Maréville , Marion Foare , Paulo Gonçalves , Nelly Pustelnik , Elisa Riccietti

In this paper we present a new regularization term for variational image restoration which can be regarded as a space-variant anisotropic extension of the classical isotropic Total Variation (TV) regularizer. The proposed regularizer comes…

Image and Video Processing · Electrical Eng. & Systems 2019-08-05 Luca Calatroni , Alessandro Lanza , Monica Pragliola , Fiorella Sgallari

Thermal images model the long-infrared range of the electromagnetic spectrum and provide meaningful information even when there is no visible illumination. Yet, unlike imagery that represents radiation from the visible continuum, infrared…

Image and Video Processing · Electrical Eng. & Systems 2021-08-03 Nolan B. Gutierrez , William J. Beksi

We propose a general learning based framework for solving nonsmooth and nonconvex image reconstruction problems. We model the regularization function as the composition of the $l_{2,1}$ norm and a smooth but nonconvex feature mapping…

Computer Vision and Pattern Recognition · Computer Science 2022-09-07 Yunmei Chen , Hongcheng Liu , Xiaojing Ye , Qingchao Zhang

In the reconstruction process of unknown multiple scattering objects in inverse medium scattering problems, the first important step is to effectively locate some approximate domains that contain all inhomogeneous media. Without such an…

Numerical Analysis · Mathematics 2015-06-12 Keji Liu , Jun Zou

We consider the task of image reconstruction while simultaneously decomposing the reconstructed image into components with different features. A commonly used tool for this is a variational approach with an infimal convolution of…

Numerical Analysis · Mathematics 2025-04-16 Tobias Wolf , Derek Driggs , Kostas Papafitsoros , Elena Resmerita , Carola-Bibiane Schönlieb

Image quality is the basis of image communication and understanding tasks. Due to the blur and noise effects caused by imaging, transmission and other processes, the image quality is degraded. Blind image restoration is widely used to…

Image and Video Processing · Electrical Eng. & Systems 2021-01-26 Ningshan Xu

The reconstruction of images from measured data is an increasing field of research. For highly under-determined problems, template-based image reconstruction provides a way of compensating for the lack of sufficient data. A caveat of this…

Optimization and Control · Mathematics 2023-05-29 Sebastian Neumayer , Antonia Topalovic

We propose a variational regularisation approach for the problem of template-based image reconstruction from indirect, noisy measurements as given, for instance, in X-ray computed tomography. An image is reconstructed from such measurements…

Optimization and Control · Mathematics 2019-04-02 Lukas F. Lang , Sebastian Neumayer , Ozan Öktem , Carola-Bibiane Schönlieb

The image deblurring problem consists of reconstructing images from blur and noise contaminated available data. In this AMS Notices article, we provide an overview of some well known numerical linear algebra techniques that are use for…

Numerical Analysis · Mathematics 2022-01-25 David Austin , Malena I. Español , Mirjeta Pasha

We tackle the problem of reflectance estimation from a set of multi-view images, assuming known geometry. The approach we put forward turns the input images into reflectance maps, through a robust variational method. The variational model…

Computer Vision and Pattern Recognition · Computer Science 2018-01-24 Jean Mélou , Yvain Quéau , Jean-Denis Durou , Fabien Castan , Daniel Cremers

Various problems in computer vision and medical imaging can be cast as inverse problems. A frequent method for solving inverse problems is the variational approach, which amounts to minimizing an energy composed of a data fidelity term and…

Computer Vision and Pattern Recognition · Computer Science 2020-06-17 Erich Kobler , Alexander Effland , Karl Kunisch , Thomas Pock

Many studies have been conducted so far on image restoration, the problem of restoring a clean image from its distorted version. There are many different types of distortion which affect image quality. Previous studies have focused on…

Computer Vision and Pattern Recognition · Computer Science 2019-04-09 Masanori Suganuma , Xing Liu , Takayuki Okatani

Modulo imaging enables high dynamic range (HDR) acquisition by cyclically wrapping saturated intensities, but accurate reconstruction remains challenging due to ambiguities between natural image edges and artificial wrap discontinuities.…

Image and Video Processing · Electrical Eng. & Systems 2026-03-02 Brayan Monroy , Jorge Bacca