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Related papers: Fast W-Projection for Wide-field Imaging

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We propose the complex-plane generalization of a powerful algebraic sequence acceleration algorithm, the Method of Weighted Averages (MWA), to guarantee exponential-cum-algebraic convergence of Fourier and Fourier-Hankel (F-H) integral…

Computational Physics · Physics 2016-02-17 Kamalesh Sainath , Fernando Teixeira , Burkay Donderici

A new generation of wide-field radio interferometers designed for 21-cm surveys is being built as drift scan instruments allowing them to observe large fractions of the sky. With large numbers of antennas and frequency channels the enormous…

Instrumentation and Methods for Astrophysics · Physics 2017-10-10 Philippe Berger , Niels Oppermann , Ue-Li Pen , J. Richard Shaw

In this short survey of the applications of wide-field, multi-object spectroscopy to galaxy evolution, large-scale structure and cosmology, I interleave summaries of the general goals and state of play in these fields with specific examples…

Astrophysics · Physics 2016-01-27 Matthew Colless

This paper presents a new algorithm, Accelerated Wirtinger Flow (AWF), for ptychographic image reconstruction from phaseless diffraction pattern measurements. AWF is based on combining Nesterov's acceleration approach with Wirtinger…

Image and Video Processing · Electrical Eng. & Systems 2018-06-29 Rui Xu , Mahdi Soltanolkotabi , Justin P. Haldar , Walter Unglaub , Joshua Zusman , Anthony F. J. Levi , Richard M. Leahy

Plane Wave imaging enables many applications that require high frame rates, including localisation microscopy, shear wave elastography, and ultra-sensitive Doppler. To alleviate the degradation of image quality with respect to conventional…

Signal Processing · Electrical Eng. & Systems 2021-12-24 Nishith Chennakeshava , Ben Luijten , Massimo Mischi , Yonina C. Eldar , Ruud J. G. van Sloun

Radio-astronomical observations are increasingly contaminated by interference, and suppression techniques become essential. A powerful candidate for interference mitigation is adaptive spatial filtering. We study the effect of spatial…

Astrophysics · Physics 2014-10-13 Amir Leshem , Alle-Jan van der Veen

In recent years, diverging-wave (DW) ultrasound imaging has become a very promising methodology for cardiovascular imaging due to its high temporal resolution. However, if they are limited in number, DW transmits provide lower image quality…

Image and Video Processing · Electrical Eng. & Systems 2020-03-25 Jingfeng Lu , Fabien Millioz , Damien Garcia , Sebastien Salles , Wanyu Liu , Denis Friboulet

We present a new algorithm for estimating the Point Spread Function (PSF) in wide-field astronomical images with extreme source crowding. Robust and accurate PSF estimation in crowded astronomical images dramatically improves the fidelity…

Image and Video Processing · Electrical Eng. & Systems 2021-02-09 Brendt Wohlberg , Przemek Wozniak

Frank-Wolfe algorithm (FW) and its variants have gained a surge of interests in machine learning community due to its projection-free property. Recently people have reduced the gradient evaluation complexity of FW algorithm to…

Machine Learning · Statistics 2018-05-22 Yan Li , Chao Qu , Huan Xu

In order to improve image quality of projection in industrial applications, generally, a standard method is to increase the current or exposure time, which might cause overexposure of detector units in areas of thin objects or backgrounds.…

Image and Video Processing · Electrical Eng. & Systems 2024-12-10 Mengyu Sun , Dimeng Xia , Shusen Zhao , Weibin Zhang , Yaobin He

A large fraction of the present-day stellar mass was formed between z=0.5 and z~3 and our understanding of the formation mechanisms at work at these epochs requires both high spatial and high spectral resolution: one shall simultaneously}…

On 3D imaging, light field cameras typically are of single shot, and however, they heavily suffer from low spatial resolution and depth accuracy. In this paper, by employing an optical projector to project a group of single high-frequency…

Image and Video Processing · Electrical Eng. & Systems 2024-04-11 Geyou Zhang , Ce Zhu , Kai Liu , Yipeng Liu

Non-line-of-sight (NLOS) imaging seeks to reconstruct hidden objects by analyzing reflections from intermediary surfaces. Existing methods typically model both the measurement data and the hidden scene in three dimensions, overlooking the…

Computer Vision and Pattern Recognition · Computer Science 2025-08-05 Yijun Wei , Jianyu Wang , Leping Xiao , Zuoqiang Shi , Xing Fu , Lingyun Qiu

This work aims at the precise and efficient computation of the x-ray projection of an image represented by a linear combination of general shifted basis functions that typically overlap. We achieve this with a suitable adaptation of ray…

Image and Video Processing · Electrical Eng. & Systems 2025-09-15 Youssef Haouchat , Sepand Kashani , Philippe Thévenaz , Michael Unser

Image optimization problems encompass many applications such as spectral fusion, deblurring, deconvolution, dehazing, matting, reflection removal and image interpolation, among others. With current image sizes in the order of megabytes, it…

Computer Vision and Pattern Recognition · Computer Science 2018-09-13 Majed El Helou , Frederike Dümbgen , Radhakrishna Achanta , Sabine Süsstrunk

Next generation radio telescopes will be much larger, more sensitive, have much larger observation bandwidth and will be capable of pointing multiple beams simultaneously. Obtaining the sensitivity, resolution and dynamic range supported by…

Instrumentation and Methods for Astrophysics · Physics 2010-09-03 Ronny Levanda , Amir Leshem

We consider fast kernel summations in high dimensions: given a large set of points in $d$ dimensions (with $d \gg 3$) and a pair-potential function (the {\em kernel} function), we compute a weighted sum of all pairwise kernel interactions…

Machine Learning · Computer Science 2015-02-16 William B. March , George Biros

Image Fusion, a technique which combines complimentary information from different images of the same scene so that the fused image is more suitable for segmentation, feature extraction, object recognition and Human Visual System. In this…

Information Theory · Computer Science 2008-12-04 R. Balasubramanian , Gaurav Bhatnagar

An optical imaging system forms an object image by recollecting light scattered by the object. However, intact optical information of the object delivered through the imaging system is deteriorated by imperfect optical elements and unwanted…

Optics · Physics 2017-03-28 SangYun Lee , Kyeoreh Lee , Seungwoo Shin , YongKeun Park

One of the most efficient ways to produce unconditional simulations is with the kernel convolution using fast Fourier transform (FFT) [1]. However, when data is located on a surface, this approach is not efficient because data needs to be…

Computation · Statistics 2016-01-18 Alexander Gribov