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Related papers: Sparse Lens Inversion Technique (SLIT): lens and s…

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Sparse-view computed tomography (CT) enables fast and low-dose CT imaging, an essential feature for patient-save medical imaging and rapid non-destructive testing. In sparse-view CT, only a few projection views are acquired, causing…

Image and Video Processing · Electrical Eng. & Systems 2024-02-28 Nadja Gruber , Johannes Schwab , Elke Gizewski , Markus Haltmeier

We present SILT, a Self-supervised Implicit Lighting Transfer method. Unlike previous research on scene relighting, we do not seek to apply arbitrary new lighting configurations to a given scene. Instead, we wish to transfer the lighting…

Computer Vision and Pattern Recognition · Computer Science 2022-03-16 Nikolina Kubiak , Armin Mustafa , Graeme Phillipson , Stephen Jolly , Simon Hadfield

We present the analysis of a sample of twenty-four SLACS-like galaxy-galaxy strong gravitational lens systems with a background source and deflectors from the Illustris-1 simulation. We study the degeneracy between the complex mass…

Astrophysics of Galaxies · Physics 2020-05-27 W. Enzi , S. Vegetti , G. Despali , J. -W. Hsueh , R. B. Metcalf

Modeling strong gravitational lenses in order to quantify the distortions in the images of background sources and to reconstruct the mass density in the foreground lenses has traditionally been a difficult computational challenge. As the…

Instrumentation and Methods for Astrophysics · Physics 2022-07-05 Alexandre Adam , Laurence Perreault-Levasseur , Yashar Hezaveh

This paper extends the sample complexity theory for ill-posed inverse problems developed in a recent work by the authors [`Compressed sensing for inverse problems and the sample complexity of the sparse Radon transform', J. Eur. Math. Soc.,…

Functional Analysis · Mathematics 2025-01-06 Giovanni S. Alberti , Alessandro Felisi , Matteo Santacesaria , S. Ivan Trapasso

(Abridged) Weak gravitational lensing is an ideal probe of the dark universe. In recent years, several linear methods have been developed to reconstruct the density distribution in the Universe in three dimensions, making use of photometric…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Adrienne Leonard , François-Xavier Dupé , Jean-Luc Starck

When taking images against strong light sources, the resulting images often contain heterogeneous flare artifacts. These artifacts can importantly affect image visual quality and downstream computer vision tasks. While collecting real data…

Image and Video Processing · Electrical Eng. & Systems 2023-09-01 Yuyan Zhou , Dong Liang , Songcan Chen , Sheng-Jun Huang , Shuo Yang , Chongyi Li

Light rays incident on a transparent object of uniform refractive index undergo deflections, which uniquely characterize the surface geometry of the object. Associated with each point on the surface is a deflection map (or spectrum) which…

Computer Vision and Pattern Recognition · Computer Science 2015-07-15 Prasad Sudhakar , Laurent Jacques , Xavier Dubois , Philippe Antoine , Luc Joannes

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

This article proposes diffusion LMS strategies for distributed estimation over adaptive networks that are able to exploit sparsity in the underlying system model. The approach relies on convex regularization, common in compressive sensing,…

Machine Learning · Computer Science 2015-06-05 Paolo Di Lorenzo , Ali H. Sayed

The information about the mass density of galaxy clusters provided by the gravitational lens effect has inspired many inversion techniques. In this article, updates to the previously introduced method in Grale are described, and explored in…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-15 Jori Liesenborgs , Liliya L. R. Williams , Jenny Wagner , Sven De Rijcke

A light field records numerous light rays from a real-world scene. However, capturing a dense light field by existing devices is a time-consuming process. Besides, reconstructing a large amount of light rays equivalent to multiple light…

Computer Vision and Pattern Recognition · Computer Science 2018-08-14 Mantang Guo , Hao Zhu , Guoqing Zhou , Qing Wang

We present a learning-based approach to relight a single image of Lambertian and low-frequency specular objects. Our method enables inserting objects from photographs into new scenes and relighting them under the new environment lighting,…

Computer Vision and Pattern Recognition · Computer Science 2023-03-27 Renjiao Yi , Chenyang Zhu , Kai Xu

This paper presents a variational based approach to fusing hyperspectral and multispectral images. The fusion process is formulated as an inverse problem whose solution is the target image assumed to live in a much lower dimensional…

Computer Vision and Pattern Recognition · Computer Science 2023-07-19 Qi Wei , José Bioucas-Dias , Nicolas Dobigeon , Jean-Yves Tourneret

We present the source separation framework SCARLET for multi-band images, which is based on a generalization of the Non-negative Matrix Factorization to alternative and several simultaneous constraints. Our approach describes the observed…

Instrumentation and Methods for Astrophysics · Physics 2018-08-14 Peter Melchior , Fred Moolekamp , Maximilian Jerdee , Robert Armstrong , Ai-Lei Sun , James Bosch , Robert Lupton

Around $10^5$ strongly lensed galaxies are expected to be discovered with Euclid and the LSST. Utilising these large samples to study the inner structure of lens galaxies requires source redshifts, to turn lens models into mass…

Cosmology and Nongalactic Astrophysics · Physics 2023-02-01 Danial Langeroodi , Alessandro Sonnenfeld , Henk Hoekstra , Adriano Agnello

Conventional algorithms for sparse signal recovery and sparse representation rely on $l_1$-norm regularized variational methods. However, when applied to the reconstruction of $\textit{sparse images}$, i.e., images where only a few pixels…

Computer Vision and Pattern Recognition · Computer Science 2016-05-09 Sohil Shah , Tom Goldstein , Christoph Studer

We consider model selection and estimation for partial spline models and propose a new regularization method in the context of smoothing splines. The regularization method has a simple yet elegant form, consisting of roughness penalty on…

Methodology · Statistics 2013-11-25 Guang Cheng , Hao Helen Zhang , Zuofeng Shang

This paper presents a new algorithmic framework for computing sparse solutions to large-scale linear discrete ill-posed problems. The approach is motivated by recent perspectives on iteratively reweighted norm schemes, viewed through the…

Numerical Analysis · Mathematics 2025-02-05 Lucas Onisk , Malena Sabaté Landman

Sparse-view computed tomography (CT) is an effective method to reduce the radiation exposure in medical imaging. To reduce the severe streaking artifacts that occur in reconstructed images due to violation of the Nyquist/Shannon sampling…

Medical Physics · Physics 2026-03-17 Huiying Li , Yizhuang Song