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Estimating continuous optical flow is a fundamental yet challenging problem in dynamic visual perception. Event-based cameras, with microsecond latency and high dynamic range, capture brightness changes asynchronously, offering a unique…

Computer Vision and Pattern Recognition · Computer Science 2026-05-27 Rui Hu , Song Wu , Wen Yang , Jinjian Wu

We present a global optimization approach to optical flow estimation. The approach optimizes a classical optical flow objective over the full space of mappings between discrete grids. No descriptor matching is used. The highly regular…

Computer Vision and Pattern Recognition · Computer Science 2016-04-13 Qifeng Chen , Vladlen Koltun

In this article, we propose a methodology to reconstruct, in a single step, the mean- and unsteady properties of a flow from very few time-resolved measurements. The procedure is based on the {\it a priori} alignement of Fourier- and…

Fluid Dynamics · Physics 2021-02-09 Lucas Franceschini , Denis Sipp , Olivier Marquet

Optical flow estimation is a fundamental and long-standing visual task. In this work, we present a novel method, dubbed HMAFlow, to improve optical flow estimation in challenging scenes, particularly those involving small objects. The…

Computer Vision and Pattern Recognition · Computer Science 2024-11-18 Dianbo Ma , Kousuke Imamura , Ziyan Gao , Xiangjie Wang , Satoshi Yamane

We present a new approach for constructing optical phase-space-time-frequency tomography (OPSTFT) of an optical wave field. This tomography can be measured by using a novel four-window optical imaging system based on two local oscillator…

Quantum Physics · Physics 2015-05-27 Paul Rojas , Rachel Blaser , Yong Meng Sua , Kim Fook Lee

Optical flow is an indispensable building block for various important computer vision tasks, including motion estimation, object tracking, and disparity measurement. In this work, we propose TransFlow, a pure transformer architecture for…

Computer Vision and Pattern Recognition · Computer Science 2023-04-25 Yawen Lu , Qifan Wang , Siqi Ma , Tong Geng , Yingjie Victor Chen , Huaijin Chen , Dongfang Liu

We introduce a framework for the reconstruction of the amplitude, phase and polarisation of an optical vector-field using calibration measurements acquired by an imaging device with an unknown linear transformation. By incorporating…

Within the expansive domain of optical sciences, achieving the precise characterization of light beams stands as a fundamental pursuit, pivotal for various applications, including telecommunications and imaging technologies. This study…

We study the inverse problem in Optical Tomography of determining the optical properties of a medium $\Omega\subset\mathbb{R}^n$, with $n\geq 3$, under the so-called diffusion approximation. We consider the time-harmonic case where $\Omega$…

Analysis of PDEs · Mathematics 2021-11-16 Jason Curran , Romina Gaburro , Clifford J. Nolan , Erkki Somersalo

Event cameras capture changes of illumination in the observed scene rather than accumulating light to create images. Thus, they allow for applications under high-speed motion and complex lighting conditions, where traditional framebased…

Computer Vision and Pattern Recognition · Computer Science 2021-12-21 Vincent Brebion , Julien Moreau , Franck Davoine

We address the problem of reconstructing phase-shifting objects from their single shot in-line holograms. We show that a phase-shifting object cannot be reliably recovered from its in-line hologram by non-iterative reconstruction routines,…

Optics · Physics 2015-06-01 Tatiana Latychevskaia , Hans-Werner Fink

In this work, we propose a time-varying wave-shape extraction algorithm based on a modified version of the adaptive non-harmonic model for non-stationary signals. The model codifies the time-varying wave-shape information in the relative…

Signal Processing · Electrical Eng. & Systems 2023-09-28 Joaquin Ruiz , Gastón Schlotthauer , Leandro Vignolo , Marcelo A. Colominas

We consider the problem of elastic diffraction tomography, which consists in reconstructing elastic properties (i.e. mass density and elastic Lam\'e parameters) of a weakly scattering medium from full-field data of scattered waves outside…

Analysis of PDEs · Mathematics 2022-12-07 Bochra Mejri , Otmar Scherzer

Event cameras are novel bio-inspired sensors that offer advantages over traditional cameras (low latency, high dynamic range, low power, etc.). Optical flow estimation methods that work on packets of events trade off speed for accuracy,…

Computer Vision and Pattern Recognition · Computer Science 2024-03-05 Shintaro Shiba , Yoshimitsu Aoki , Guillermo Gallego

The mechanism of wavefront reconstruction by a geometric-optical reflection of reconstructing light from surfaces with constant phase differences between the object and reference waves used to record the interference fringe structure in the…

General Physics · Physics 2020-12-02 A. M. Smolovich

This paper is concerned with a space-time adaptive numerical method for instationary porous media flows with nonlinear interaction between porosity and pressure, with focus on problems with discontinuous initial porosities. A convergent…

Numerical Analysis · Mathematics 2025-08-27 Markus Bachmayr , Simon Boisserée

Optical coherence tomography (OCT) is a non-invasive, micrometer-scale imaging modality that has become a clinical standard in ophthalmology. By raster-scanning the retina, sequential cross-sectional image slices are acquired to generate…

Image and Video Processing · Electrical Eng. & Systems 2024-02-20 Stefan Ploner , Jungeun Won , Julia Schottenhamml , Jessica Girgis , Kenneth Lam , Nadia Waheed , James Fujimoto , Andreas Maier

Retrospective MRI harmonization is limited by poor scalability across modalities and reliance on traveling subject datasets. To address these challenges, we introduce IHF-Harmony, a unified invertible hierarchy flow framework for…

Computer Vision and Pattern Recognition · Computer Science 2026-05-18 Pengli Zhu , Yitao Zhu , Haowen Pang , Anqi Qiu

We study the volatility functional inference by Fourier transforms. This spectral framework is advantageous in that it harnesses the power of harmonic analysis to handle missing data and asynchronous observations without any artificial time…

Statistics Theory · Mathematics 2019-11-07 Richard Y. Chen

We present a system for measuring the amplitude and phase profiles of the pressure field of a harmonic acoustic wave with the goal of reconstructing the volumetric sound field. Unlike optical holograms that cannot be reconstructed exactly…

Soft Condensed Matter · Physics 2018-08-09 Hillary W. Gao , Kimberly I. Mishra , Annemarie Winters , Sidney Wolin , David G. Grier