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

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Limited-Angle Computed Tomography (LACT) is a challenging inverse problem where missing angular projections lead to incomplete sinograms and severe artifacts in the reconstructed images. While recent learning-based methods have demonstrated…

Image and Video Processing · Electrical Eng. & Systems 2025-07-09 Jiaqi Guo , Santiago López-Tapia

We aim at the solution of inverse problems in imaging, by combining a penalized sparse representation of image patches with an unconstrained smooth one. This allows for a straightforward interpretation of the reconstruction. We formulate…

Image and Video Processing · Electrical Eng. & Systems 2025-03-18 Stanislas Ducotterd , Sebastian Neumayer , Michael Unser

Global localization plays a critical role in many robot applications. LiDAR-based global localization draws the community's focus with its robustness against illumination and seasonal changes. To further improve the localization under large…

Robotics · Computer Science 2022-10-13 Xuecheng Xu , Sha Lu , Jun Wu , Haojian Lu , Qiuguo Zhu , Yiyi Liao , Rong Xiong , Yue Wang

Restoration of images degraded by spatially varying blurs is an issue of increasing importance in the context of photography, satellite or microscopy imaging. One of the main difficulty to solve this problem comes from the huge dimensions…

Optimization and Control · Mathematics 2015-06-15 Paul Escande , Pierre Weiss , Francois Malgouyres

We present the experimental reconstruction of sub-wavelength features from the far-field intensity of sparse optical objects: sparsity-based sub-wavelength imaging combined with phase-retrieval. As examples, we demonstrate the recovery of…

In the near future, ultra deep observations of galaxy clusters with HST or JWST will uncover $300-1000$ lensed multiple images, increasing the current count per cluster by up to an order of magnitude. This will further refine our view of…

Cosmology and Nongalactic Astrophysics · Physics 2020-04-07 Agniva Ghosh , Liliya L. R. Williams , Jori Liesenborgs

The high complexity of various inverse problems poses a significant challenge to model-based reconstruction schemes, which in such situations often reach their limits. At the same time, we witness an exceptional success of data-based…

Computer Vision and Pattern Recognition · Computer Science 2019-09-04 T. A. Bubba , G. Kutyniok , M. Lassas , M. März , W. Samek , S. Siltanen , V. Srinivasan

Image structure-texture decomposition is a long-standing and fundamental problem in both image processing and computer vision fields. In this paper, we propose a generalized semi-sparse regularization framework for image structural analysis…

Computer Vision and Pattern Recognition · Computer Science 2023-08-21 Junqing Huang , Haihui Wang , Michael Ruzhansky

In this study, we investigate the inverse source problem arising in bioluminescence tomography, the objective of which is to reconstruct both the support and the intensity of an internal light source from boundary measurements governed by…

Numerical Analysis · Mathematics 2025-11-25 Qianqian Wu , Rongfang Gong , Wei Gong , Ziyi Zhang , Shengfeng Zhu

Many works in elasticity have exploited the concept of gradient index (GRIN) lenses, borrowed from optics, for wave focusing and control. These effects are particularly attractive for cloaking, absorption or energy harvesting applications.…

Applied Physics · Physics 2024-09-04 P. H. Beoletto , F. Nistri , A. S. Gliozzi , N. M. Pugno , F. Bosia

Many imaging science tasks can be modeled as a discrete linear inverse problem. Solving linear inverse problems is often challenging, with ill-conditioned operators and potentially non-unique solutions. Embedding prior knowledge, such as…

Numerical Analysis · Mathematics 2023-12-07 Elizabeth Newman , Jack Michael Solomon , Matthias Chung

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The…

General Relativity and Quantum Cosmology · Physics 2011-09-28 Thomas P. Kling , Louis Bianchini

In the strong lensing regime non-parametric lens models struggle to achieve sufficient angular resolution for a meaningful derivation of the central cluster mass distribution. The problem lies mainly with cluster members which perturb…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Irene Sendra , Jose M. Diego , Tom Broadhurst , Ruth Lazkoz

This investigation is motivated by PDE-constrained optimization problems arising in connection with electrocardiograms (ECGs) and electroencephalography (EEG). Standard sparsity regularization does not necessarily produce adequate results…

Numerical Analysis · Mathematics 2023-05-25 Ole Løseth Elvetun , Bjørn Fredrik Nielsen

Forthcoming radio surveys will include full polarisation information, which can be potentially useful for weak lensing observations. We propose a new method to measure the (integrated) gravitational field between a source and the observer,…

Astrophysics of Galaxies · Physics 2021-12-08 Jérémie Francfort , Giulia Cusin , Ruth Durrer

In a recent article series, the authors have promoted convex optimization algorithms for radio-interferometric imaging in the framework of compressed sensing, which leverages sparsity regularization priors for the associated inverse problem…

Instrumentation and Methods for Astrophysics · Physics 2014-04-01 Rafael E. Carrillo , Jason D. McEwen , Yves Wiaux

We propose and analyze an online algorithm for reconstructing a sequence of signals from a limited number of linear measurements. The signals are assumed sparse, with unknown support, and evolve over time according to a generic nonlinear…

Optimization and Control · Mathematics 2015-03-12 Joao F. C. Mota , Nikos Deligiannis , Aswin C. Sankaranarayanan , Volkan Cevher , Miguel R. D. Rodrigues

The main obstacle for gravitational lensing to determine accurate masses of deflectors, or to determine precise estimates for the Hubble constant, is the degeneracy of lensing observables with respect to the mass-sheet transformation (MST).…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-08 Peter Schneider , Dominique Sluse

Learned Sparse Retrieval (LSR) is an effective IR approach that exploits pre-trained language models for encoding text into a learned bag of words. Several efforts in the literature have shown that sparsity is key to enabling a good…

Information Retrieval · Computer Science 2025-05-06 Franco Maria Nardini , Thong Nguyen , Cosimo Rulli , Rossano Venturini , Andrew Yates

Classical total variation (TV) based iterative reconstruction algorithms assume that the signal is piecewise smooth, which causes reconstruction results to suffer from the over-smoothing effect. To address this problem, this work presents a…

Medical Physics · Physics 2018-03-06 Peng Bao , Jiliu Zhou , Yi Zhang