English
Related papers

Related papers: Background Oriented Schlieren in a Density Stratif…

200 papers

Liquid crystals are materials that experience an intermediate phase where the material can flow like a liquid, but the molecules maintain an orientation order. The Frank-Oseen model is a continuum model of a liquid crystal. The model…

Numerical Analysis · Mathematics 2024-05-07 Lucas Bouck , Ricardo H. Nochetto

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

Statistical surrogate modeling of fluid flows is hard because dynamics are multiscale and highly sensitive to initial conditions. Conditional diffusion surrogates can be accurate, but usually need hundreds of stochastic sampling steps. We…

Machine Learning · Computer Science 2026-02-10 Victor Armegioiu , Yannick Ramic , Siddhartha Mishra

The precise simulation of turbulent flows holds immense significance across various scientific and engineering domains, including climate science, freshwater science, and energy-efficient manufacturing. Within the realm of simulating…

Fluid Dynamics · Physics 2024-12-31 Shengyu Chen , Peyman Givi , Can Zheng , Xiaowei Jia

Data acquisition, image processing, and image quality are the long-lasting issues for terahertz (THz) 3D reconstructed imaging. Existing methods are primarily designed for 2D scenarios, given the challenges associated with obtaining…

Optics · Physics 2024-03-28 Yiyao Zhang , Ke Chen , Shang-Hua Yang

Measurement of the velocity field in thermal-hydraulic experiments is of great importance for phenomena interpretation and code validation. Direct measurement employing Particle Image Velocimetry (PIV) is challenging in some multiphase…

Fluid Dynamics · Physics 2025-09-03 Xicheng Wang , YiMeng Chan , KinWing Wong , Dmitry Grishchenko , Pavel Kudinov

Ptychography is a lensless, computational imaging method that utilises diffraction patterns to determine the amplitude and phase of an object. In transmission ptychography, the diffraction patterns are recorded by a detector positioned…

Image and Video Processing · Electrical Eng. & Systems 2023-01-04 Kira A. M. Maathuis , Jacob Seifert , Allard P. Mosk

Background Subtraction (BS) is one of the key steps in video analysis. Many background models have been proposed and achieved promising performance on public data sets. However, due to challenges such as illumination change, dynamic…

Computer Vision and Pattern Recognition · Computer Science 2015-04-16 Bo Xin , Yuan Tian , Yizhou Wang , Wen Gao

An improved neural refractive-index-primitive method for background-oriented schlieren tomography is presented, enabling continuous three-dimensional reconstruction of refractive-index fields using a compact multilayer perceptron. The…

Fluid Dynamics · Physics 2026-05-15 Xinyi Lu , Wei Hu , Zizhou Liao , Zheng Wang , Yue Zhang , Jingxuan Li

In this paper, we present a novel reconstruction method for diffuse optical spectroscopic imaging with a commonly used tissue model of optical absorption and scattering. It is based on linearization and group sparsity, which allows…

Numerical Analysis · Mathematics 2019-03-06 Habib Ammari , Bangti Jin , Wenlong Zhang

A novel algorithm for the direct numerical simulation of the variable-density, low-Mach Navier-Stokes equations extending the method of Kim, Moin, and Moser (1987) for incompressible flow is presented here. A Fourier representation is…

Fluid Dynamics · Physics 2022-06-22 Bryan W. Reuter , Todd A. Oliver , Robert D. Moser

Optical Remote Sensing Image Salient Object Detection (ORSI-SOD) remains challenging due to complex backgrounds, low contrast, irregular object shapes, and large variations in object scale. Existing discriminative methods directly regress…

Computer Vision and Pattern Recognition · Computer Science 2026-04-27 Haojing Chen , Zhihang Liu , Yutong Li , Tao Tan , Haoyu Bian , Qiuju Ma

Reconstructing precise camera poses and floor plan layouts from wide-baseline RGB panoramas is a difficult and unsolved problem. We introduce BADGR, a novel diffusion model that jointly performs reconstruction and bundle adjustment (BA) to…

Computer Vision and Pattern Recognition · Computer Science 2025-03-26 Yuguang Li , Ivaylo Boyadzhiev , Zixuan Liu , Linda Shapiro , Alex Colburn

Many normalizing flow architectures impose regularity constraints, yet their distributional approximation properties are not fully characterized. We study the expressivity of bi-Lipschitz normalizing flows through the lens of score-based…

Machine Learning · Statistics 2026-05-08 Meira Iske , Carola-Bibiane Schönlieb

Non-line-of-sight (NLOS) imaging aims at reconstructing targets obscured from the direct line of sight. Existing NLOS imaging algorithms require dense measurements at rectangular grid points in a large area of the relay surface, which…

Image and Video Processing · Electrical Eng. & Systems 2023-06-21 Xintong Liu , Jianyu Wang , Leping Xiao , Zuoqiang Shi , Xing Fu , Lingyun Qiu

Watermarking is an important mechanism for provenance and copyright protection of diffusion-generated images. Training-free methods, exemplified by Gaussian Shading, embed watermarks into the initial noise of diffusion models with…

Computer Vision and Pattern Recognition · Computer Science 2026-02-11 Yuwei Chen , Zhenliang He , Jia Tang , Meina Kan , Shiguang Shan

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

Wasserstein barycenters provide a principled approach for aggregating probability measures, while preserving the geometry of their ambient space. Existing discrete methods are not scalable as they assume access to the complete set of…

Machine Learning · Statistics 2026-03-10 Eduardo Fernandes Montesuma , Yassir Bendou , Mike Gartrell

Scene flow is the dense 3D reconstruction of motion and geometry of a scene. Most state-of-the-art methods use a pair of stereo images as input for full scene reconstruction. These methods depend a lot on the quality of the RGB images and…

Computer Vision and Pattern Recognition · Computer Science 2020-08-20 Rishav , Ramy Battrawy , René Schuster , Oliver Wasenmüller , Didier Stricker

Light rays incident on a transparent object of uniform refractive index undergo deflections, which uniquely characterize the surface geometry of the object. Associated with each point on the surface is a deflection map (or spectrum) which…

Computer Vision and Pattern Recognition · Computer Science 2015-07-15 Prasad Sudhakar , Laurent Jacques , Xavier Dubois , Philippe Antoine , Luc Joannes