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Related papers: Scale factor point spread function matching: Beyon…

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This paper introduces the Wide-band Asp-Clean (\texttt{WAsp}) algorithm, a novel scale-sensitive image reconstruction method tailored for wide-band imaging applications. This algorithm is particularly beneficial for thermal noise-limited…

Instrumentation and Methods for Astrophysics · Physics 2026-04-27 M. Hsieh , S. Bhatnagar , U. Rau

An undersampled point spread function may interact with the microstructure of a solid-state detector such that the total flux detected can depend sensitively on where the PSF center falls within a pixel. Such intra-pixel sensitivity…

Astrophysics · Physics 2009-10-31 Tod R. Lauer

Dense random sampling and surfacing of shapes encoded via implicit occupancy functions (OFs) are critical elements of many applications. Existing methods largely provide either one or the other of random sampling or mesh surfaces: ray…

Graphics · Computer Science 2026-05-06 Suzuran Takikawa , Leo Foord-Kelcey , Oliver Oxford , Nicholas Vining , Alla Sheffer

We present a novel approach to implement compressive sensing in laser scanning microscopes (LSM), specifically in image scanning microscopy (ISM), using a single-photon avalanche diode (SPAD) array detector. Our method addresses two…

Image and Video Processing · Electrical Eng. & Systems 2023-07-20 Ajay Gunalan , Marco Castello , Simonluca Piazza , Shunlei Li , Alberto Diaspro , Leonardo S. Mattos , Paolo Bianchini

Efficient estimators of Fourier-space statistics for large number of objects rely on Fast Fourier Transforms (FFTs), which are affected by aliasing from unresolved small scale modes due to the finite FFT grid. Aliasing takes the form of a…

Cosmology and Nongalactic Astrophysics · Physics 2017-10-09 Emiliano Sefusatti , Martin Crocce , Roman Scoccimarro , Hugh Couchman

Convolutional Neural Networks (CNNs) are the predominant model used for a variety of medical image analysis tasks. At inference time, these models are computationally intensive, especially with volumetric data. In principle, it is possible…

Computer Vision and Pattern Recognition · Computer Science 2023-06-30 Jose Javier Gonzalez Ortiz , John Guttag , Adrian Dalca

Weakly-supervised semantic segmentation (WSSS), which aims to train segmentation models solely using image-level labels, has achieved significant attention. Existing methods primarily focus on generating high-quality pseudo labels using…

Computer Vision and Pattern Recognition · Computer Science 2024-11-27 Wangyu Wu , Tianhong Dai , Xiaowei Huang , Fei Ma , Jimin Xiao

Sampling is a pivotal element in the design of metasurfaces, enabling a broad spectrum of applications. Despite its flexibility, sampling can result in reduced efficiency and unintended diffractions, which are more pronounced at high…

Optics · Physics 2024-06-18 Seokwoo Kim , Joohoon Kim , Kyungtae Kim , Minsu Jeong , Junsuk Rho

Images from adaptive optics systems are generally affected by significant distortions of the point spread function (PSF) across the field of view, depending on the position of natural and artificial guide stars. Image reduction techniques…

Instrumentation and Methods for Astrophysics · Physics 2015-06-24 Andrea La Camera , Laura Schreiber , Emiliano Diolaiti , Patrizia Boccacci , Mario Bertero , Michele Bellazzini , Paolo Ciliegi

We analyze the aliasing phenomenon for digital Fresnel hologram with an enhanced numerical aperture (NA). The enhanced-NA digital hologram acquired computationally or optically at a closer distance from the object has an aliased fringe…

Optics · Physics 2020-05-28 Byung Gyu Chae

We present a detailed analysis of the point spread function (PSF) of JWST NIRCam imaging in eight filters: F070W, F115W, F150W, F200W, F277W, F356W, F444W, and F480M, using publicly available data. Spatial variations in the PSF FWHM…

Astrophysics of Galaxies · Physics 2023-04-28 Ming-Yang Zhuang , Yue Shen

Even though image signals are typically defined on a regular two-dimensional grid, there also exist many scenarios where this is not the case and the amplitude of the image signal only is available for a non-regular subset of pixel…

Image and Video Processing · Electrical Eng. & Systems 2022-04-28 Jürgen Seiler , Markus Jonscher , Michael Schöberl , André Kaup

Despite diffusion models' superior capabilities in modeling complex distributions, there are still non-trivial distributional discrepancies between generated and ground-truth images, which has resulted in several notable problems in image…

Computer Vision and Pattern Recognition · Computer Science 2024-10-08 Yujian Liu , Yang Zhang , Tommi Jaakkola , Shiyu Chang

Interferometric scattering (iSCAT) microscopy is an emerging label-free technique optimized for the sensitive detection of nano-matter. Previous iSCAT studies have approximated the point spread function in iSCAT by a Gaussian intensity…

Undersampled images, such as those produced by the HST WFPC-2, misrepresent fine-scale structure intrinsic to the astronomical sources being imaged. Analyzing such images is difficult on scales close to their resolution limits and may…

Astrophysics · Physics 2009-10-31 Tod R. Lauer

We study the impact of sampling theorems on the fidelity of sparse image reconstruction on the sphere. We discuss how a reduction in the number of samples required to represent all information content of a band-limited signal acts to…

Information Theory · Computer Science 2013-04-17 J. D. McEwen , G. Puy , J. -Ph. Thiran , P. Vandergheynst , D. Van De Ville , Y. Wiaux

Quality assessment of images and videos emphasizes both local details and global semantics, whereas general data sampling methods (e.g., resizing, cropping or grid-based fragment) fail to catch them simultaneously. To address the…

Computer Vision and Pattern Recognition · Computer Science 2024-01-08 Yongxu Liu , Yinghui Quan , Guoyao Xiao , Aobo Li , Jinjian Wu

(abridged) We examine the spatial and temporal stability of the HST ACS Wide Field Camera (WFC) point spread function (PSF) using the two square degree COSMOS survey. We show that stochastic aliasing of the PSF necessarily occurs during…

Spatial sampling is traditionally studied in a static setting where static sensors scattered around space take measurements of the spatial field at their locations. In this paper we study the emerging paradigm of sampling and reconstructing…

Multimedia · Computer Science 2015-06-12 Jayakrishnan Unnikrishnan , Martin Vetterli

We consider the problem of reconstructing a compactly supported function from samples of its Fourier transform taken along a spiral. We determine the Nyquist sampling rate in terms of the density of the spiral and show that below this rate…

Classical Analysis and ODEs · Mathematics 2022-05-04 Philippe Jaming , Felipe Negreira , José Luis Romero