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Photometric pipelines struggle to estimate both the flux and flux uncertainty for stars in the presence of structured backgrounds such as filaments or clouds. However, it is exactly stars in these complex regions that are critical to…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Andrew K. Saydjari , Douglas P. Finkbeiner

Star test polarimetry is an imaging polarimetry technique in which an element with spatially-varying birefringence is placed in the pupil plane to encode polarization information into the point-spread function (PSF) of an imaging system. In…

Instrumentation and Methods for Astrophysics · Physics 2020-01-08 Anthony Vella , Miguel A. Alonso

The Point Spread Function (PSF) is a key figure of merit for specifying the angular resolution of optical systems and, as the demand for higher and higher angular resolution increases, the problem of surface finishing must be taken…

Instrumentation and Methods for Astrophysics · Physics 2016-10-04 K. Tayabaly , D. Spiga , G. Sironi , R. Canestrari , M. Lavagna , G. Pareschi

Ultrasound imaging systems rely on accurate point spread function (PSF) estimation to support advanced image quality enhancement techniques such as deconvolution and speckle reduction. Phase aberration, caused by sound speed inhomogeneity…

Signal Processing · Electrical Eng. & Systems 2025-02-24 Wei-Hsiang Shen , Yu-An Lin , Meng-Lin Li

This paper investigates score-based diffusion models when the underlying target distribution is concentrated on or near low-dimensional manifolds within the higher-dimensional space in which they formally reside, a common characteristic of…

Machine Learning · Computer Science 2025-01-03 Gen Li , Yuling Yan

Current Structure-from-Motion (SfM) methods typically follow a two-stage pipeline, combining learned or geometric pairwise reasoning with a subsequent global optimization step. In contrast, we propose a data-driven multi-view reasoning…

Computer Vision and Pattern Recognition · Computer Science 2025-05-09 Qitao Zhao , Amy Lin , Jeff Tan , Jason Y. Zhang , Deva Ramanan , Shubham Tulsiani

Ptychography is an imaging technique which involves a sample being illuminated by a coherent, localized probe of illumination. When the probe interacts with the sample, the light is diffracted and a diffraction pattern is detected. Then the…

Numerical Analysis · Mathematics 2023-01-31 Mark Iwen , Michael Perlmutter , Mark Philip Roach

Localization microscopy enables imaging with resolutions that surpass the conventional optical diffraction limit. Notably, the MINFLUX method achieves super-resolution by shaping the excitation point-spread function (PSF) to minimize the…

The image subtraction method is a powerful tool to analyze the light variations in crowded fields. This method is able to achieve a nearly optimal differential photometry, even in very dense regions. However, image subtraction is not…

Astrophysics · Physics 2007-05-23 C. Alard

The Large Synoptic Survey Telescope (LSST) will survey the southern sky from 2022--2032 with unprecedented detail. Since the observing strategy can lead to artifacts in the data, we investigate the effects of telescope-pointing offsets…

Cosmic shear has been identified as the method with the most potential to constrain dark energy. To capitalise on this potential it is necessary to measure galaxy shapes with great accuracy, which in turn requires a detailed model for the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 L. M. Voigt , S. L. Bridle , A. Amara , M. Cropper , T. D. Kitching , R. Massey , J. Rhodes , T. Schrabback

While perspective is a well-studied topic in art, it is generally taken for granted in images. However, for the recent wave of high-quality image synthesis methods such as latent diffusion models, perspective accuracy is not an explicit…

Computer Vision and Pattern Recognition · Computer Science 2023-12-05 Rishi Upadhyay , Howard Zhang , Yunhao Ba , Ethan Yang , Blake Gella , Sicheng Jiang , Alex Wong , Achuta Kadambi

Point spread function (PSF) engineering has been pivotal in the remarkable progress made in high-resolution imaging in the last decades. However, the diversity in PSF structures attainable through existing engineering methods is limited.…

Optics · Physics 2025-06-10 Md Sadman Sakib Rahman , Aydogan Ozcan

Point spread function (PSF) plays an essential role in image reconstruction. In the context of confocal microscopy, optical performance degrades towards the edge of the field of view as astigmatism, coma and vignetting. Thus, one should…

Computer Vision and Pattern Recognition · Computer Science 2017-08-01 Anna Jezierska , Hugues Talbot , Jean-Christophe Pesquet , Gilbert Engler

We present a method to estimate dense depth by optimizing a sparse set of points such that their diffusion into a depth map minimizes a multi-view reprojection error from RGB supervision. We optimize point positions, depths, and weights…

Computer Vision and Pattern Recognition · Computer Science 2021-06-30 Numair Khan , Min H. Kim , James Tompkin

In a previous work we have demonstrated a novel numerical model for the point spread function (PSF) of an optical system that can efficiently model both experimental measurements and lens design simulations of the PSF. The novelty lies in…

Image and Video Processing · Electrical Eng. & Systems 2018-06-25 Matthias Lehmann , Christian Wittpahl , Hatem Ben Zakour , Alexander Braun

Gaze following aims to predict where a person is looking in a scene, by predicting the target location, or indicating that the target is located outside the image. Recent works detect the gaze target by training a heatmap regression task…

Computer Vision and Pattern Recognition · Computer Science 2022-11-22 Qiaomu Miao , Minh Hoai , Dimitris Samaras

The quantitative phase image formation process is posed as a problem of parameter estimation from intensity measurements. This approach is inclusive of traditional pixel-oriented imaging, where the sought parameters are the pixel values.…

Classical Physics · Physics 2024-07-04 George Barbastathis

We present an expanded and improved deep-learning (DL) methodology for determining centers of star images on HST/WFPC2 exposures. Previously, we demonstrated that our DL model can eliminate the pixel-phase bias otherwise present in these…

Instrumentation and Methods for Astrophysics · Physics 2024-04-29 Dana I. Casetti-Dinescu , Roberto Baena-Galle , Terrence M. Girard , Alejandro Cervantes-Rovira , Sebastian Todeasa

In this paper, we propose a novel coarse-to-fine continuous pose diffusion method to enhance the precision of pick-and-place operations within robotic manipulation tasks. Leveraging the capabilities of diffusion networks, we facilitate the…

Robotics · Computer Science 2025-02-18 Shih-Wei Guo , Tsu-Ching Hsiao , Yu-Lun Liu , Chun-Yi Lee
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