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Compressive sensing (CS) reconstructs images from sub-Nyquist measurements by solving a sparsity-regularized inverse problem. Traditional CS solvers use iterative optimizers with hand crafted sparsifiers, while early data-driven methods…

Computer Vision and Pattern Recognition · Computer Science 2023-06-02 Pamuditha Somarathne , Tharindu Wickremasinghe , Amashi Niwarthana , A. Thieshanthan , Chamira U. S. Edussooriya , Dushan N. Wadduwage

In this chapter, we discuss recent work on learning sparse approximations to high-dimensional functions on data, where the target functions may be scalar-, vector- or even Hilbert space-valued. Our main objective is to study how the…

Numerical Analysis · Mathematics 2022-02-08 Ben Adcock , Juan M. Cardenas , Nick Dexter , Sebastian Moraga

Signal reconstruction from a sample using an orthogonal projector onto a guiding subspace is theoretically well justified, but may be difficult to practically implement. We propose more general guiding operators, which increase signal…

Computer Vision and Pattern Recognition · Computer Science 2017-09-08 Andrew Knyazev , Alexander Malyshev

Under investigation is the problem of finding the best approximation of a function in a Hilbert space subject to convex constraints and prescribed nonlinear transformations. We show that in many instances these prescriptions can be…

Functional Analysis · Mathematics 2021-06-17 Patrick L. Combettes , Zev C. Woodstock

The problem of reconstruction a function from spherical means is at the heart of several modern imaging modalities and other applications. In this paper we derive universal back-projection type reconstruction formulas for recovering a…

Analysis of PDEs · Mathematics 2015-01-20 Markus Haltmeier

We introduce a method to reconstruct an element of a Hilbert space in terms of an arbitrary finite collection of linearly independent reconstruction vectors, given a finite number of its samples with respect to any Riesz basis. As we…

Numerical Analysis · Mathematics 2010-12-01 Ben Adcock , Anders C. Hansen

We examine the problem of selecting a small set of linear measurements for reconstructing high-dimensional signals. Well-established methods for optimizing such measurements include principal component analysis (PCA), independent component…

Computer Vision and Pattern Recognition · Computer Science 2025-08-06 Ling-Qi Zhang , Zahra Kadkhodaie , Eero P. Simoncelli , David H. Brainard

New techniques based on weak measurements have recently been introduced to the field of quantum state reconstruction. Some of them allow the direct measurement of each matrix element of an unknown density operator and need only $O(d)$…

Quantum Physics · Physics 2019-01-31 Luca Calderaro , Giulio Foletto , Daniele Dequal , Paolo Villoresi , Giuseppe Vallone

In this paper we consider adaptive sampling's local-feature size, used in surface reconstruction and geometric inference, with respect to an arbitrary landmark set rather than the medial axis and relate it to a path-based adaptive metric on…

Computational Geometry · Computer Science 2018-07-24 Nicholas J. Cavanna , Donald R. Sheehy

The topic of the paper is the position reconstruction from signals of segmented detectors. With the help of a simple simulation, it is shown that the position reconstruction using the centre-of-gravity method is strongly biased, if the…

Instrumentation and Detectors · Physics 2021-09-15 A. Ebrahimi , F. Feind , E. Fretwurst , E. Garutti , M. Hajheidari , R. Klanner , D. Pitzl , J. Schwandt , G. Steinbrueck , I. Zoi

Undersampling the k-space during MR acquisitions saves time, however results in an ill-posed inversion problem, leading to an infinite set of images as possible solutions. Traditionally, this is tackled as a reconstruction problem by…

Image and Video Processing · Electrical Eng. & Systems 2022-02-10 Kerem C. Tezcan , Neerav Karani , Christian F. Baumgartner , Ender Konukoglu

Recently efforts have been made to use generalized sinc functions to perfectly reconstruct various kinds of non-bandlimited signals. As a consequence, perfect reconstruction sampling formulas have been established using such generalized…

Information Theory · Computer Science 2012-12-18 Youfa Li , Qiuhui Chen , Tao Qian , Yi Wang

In this paper, we propose a probabilistic reduced-dimensional vector autoregressive (PredVAR) model to extract low-dimensional dynamics from high-dimensional noisy data. The model utilizes an oblique projection to partition the measurement…

Machine Learning · Statistics 2026-01-05 Yanfang Mo , S. Joe Qin

The need for tomographic reconstruction from sparse measurements arises when the measurement process is potentially harmful, needs to be rapid, or is uneconomical. In such cases, information from previous longitudinal scans of the same…

Image and Video Processing · Electrical Eng. & Systems 2019-09-13 Preeti Gopal , Sharat Chandran , Imants Svalbe , Ajit Rajwade

Weighted average sampling is more practical and numerically more stable than sampling at single points as in the classical Shannon sampling framework. Using the frame theory, one can completely reconstruct a bandlimited function from its…

Information Theory · Computer Science 2014-07-04 Haizhang Zhang

Consider a Gaussian memoryless multiple source with $m$ components with joint probability distribution known only to lie in a given class of distributions. A subset of $k \leq m$ components are sampled and compressed with the objective of…

Information Theory · Computer Science 2018-03-16 Vinay Praneeth Boda

We present a method for reconstructing two-dimensional velocity fields at specified length scales using observational data from tracer particles in a flow, without the need for interpolation or smoothing. The algorithm, adapted from…

Fluid Dynamics · Physics 2010-04-28 Douglas H. Kelley , Nicholas T. Ouellette

Limited angular resolution is one of the main obstacles for practical applications of light fields. Although numerous approaches have been proposed to enhance angular resolution, view selection strategies have not been well explored in this…

Computer Vision and Pattern Recognition · Computer Science 2020-08-12 Yang Chen , Martin Alain , Aljosa Smolic

In this paper, we address the inverse problem of reconstructing a scene as well as the camera motion from the image sequence taken by an omni-directional camera. Our structure from motion results give sharp conditions under which the…

Computer Vision and Pattern Recognition · Computer Science 2007-08-21 Oliver Knill , Jose Ramirez-Herran

Stratified sampling is a fast and simple method to generate point sets with uniform distribution in hypercubes. However, for the most common paraxial stratfication it has the prominent drawback that the number of sampled points in n…

Computation · Statistics 2018-06-14 Simon Wessing