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We present a method that leverages the complementarity of event cameras and standard cameras to track visual features with low-latency. Event cameras are novel sensors that output pixel-level brightness changes, called "events". They offer…

Computer Vision and Pattern Recognition · Computer Science 2019-01-21 Daniel Gehrig , Henri Rebecq , Guillermo Gallego , Davide Scaramuzza

Particle image (PI) overlap presents a significant challenge in single-camera particle tracking and sizing techniques such as Defocusing Particle Tracking Velocimetry (DPTV) and Interferometric Particle Imaging (IPI). In DPTV, overlap…

Instrumentation and Detectors · Physics 2025-06-24 Christian Sax , Jochen Kriegseis

Estimating the pose of a moving camera from monocular video is a challenging problem, especially due to the presence of moving objects in dynamic environments, where the performance of existing camera pose estimation methods are susceptible…

Computer Vision and Pattern Recognition · Computer Science 2022-07-20 Wang Zhao , Shaohui Liu , Hengkai Guo , Wenping Wang , Yong-Jin Liu

We investigate the systematic errors in measured plasma velocity distribution functions and their corresponding velocity moments, arising from the limited energy and angular resolution of top-hat electrostatic analyzers. For this purpose,…

Anytime a robot manipulator is controlled via visual feedback, the transformation between the robot and camera frame must be known. However, in the case where cameras can only capture a portion of the robot manipulator in order to better…

Robotics · Computer Science 2021-09-07 Florian Richter , Jingpei Lu , Ryan K. Orosco , Michael C. Yip

Contrary to conventional frame-based imaging, event-based vision (EBV) or dynamic vision sensing (DVS) asynchronously records binary signals of intensity changes for given pixels with microsecond resolution. The present work explores the…

Fluid Dynamics · Physics 2022-06-22 Christian Willert , Joachim Klinner

In this paper we study the dissipative effects and decoherence induced on a particle moving at constant speed in front of a dielectric plate in quantum vacuum, developing a Closed-Time-Path (CTP) integral formulation in order to account for…

Quantum Physics · Physics 2019-05-22 Ludmila Viotti , M. Belén Farías , Paula I. Villar , Fernando C. Lombardo

Local correlation tracking techniques are used to measure proper motions in a series of high angular resolution (~0.1 arcsec) penumbra images. If these motions trace true plasma motions, then we have detected converging flows that arrange…

Astrophysics · Physics 2009-11-13 I. Marquez , J. Sanchez Almeida , J. A. Bonet

Motion of active particles, such as catalytic micro- and nano-motors, is usually characterized via either dynamic light scattering or optical microscopy. In both cases, speed of particles is obtained from the calculus of the mean square…

We present a novel approach to estimating physical properties of objects from video. Our approach consists of a physics engine and a correction estimator. Starting from the initial observed state, object behavior is simulated forward in…

Computer Vision and Pattern Recognition · Computer Science 2022-06-03 Martin Link , Max Schwarz , Sven Behnke

Particle Image Velocimetry (PIV) is a classical flow estimation problem which is widely considered and utilised, especially as a diagnostic tool in experimental fluid dynamics and the remote sensing of environmental flows. Recently, the…

Computer Vision and Pattern Recognition · Computer Science 2020-07-30 Mingrui Zhang , Matthew D. Piggott

In recent years, there are increasing evidence for a thermal emission component that accompanies the overall non-thermal spectra of the prompt emission phase in GRBs. Both the temperature and flux of the thermal emission show a well defined…

Astrophysics · Physics 2009-11-13 Asaf Pe'er

Tracking with a Pan-Tilt-Zoom (PTZ) camera has been a research topic in computer vision for many years. Compared to tracking with a still camera, the images captured with a PTZ camera are highly dynamic in nature because the camera can…

Computer Vision and Pattern Recognition · Computer Science 2017-12-05 Yucao Tang , Guillaume-Alexandre Bilodeau

Methods to extract information from the tracking of mobile objects/particles have broad interest in biological and physical sciences. Techniques based on simple criteria of proximity in time-consecutive snapshots are useful to identify the…

Data Analysis, Statistics and Probability · Physics 2015-03-13 M. Chertkov , L. Kroc , F. Krzakala , M. Vergassola , L. Zdeborová

3D motion tracking is a critical task in many computer vision applications. Unsupervised markerless 3D motion tracking systems determine the most relevant object in the screen and then track it by continuously estimating its projection…

Computer Vision and Pattern Recognition · Computer Science 2012-03-19 Luis Quesada

We compare experimental data and numerical simulations for the dynamics of inertial particles with finite density in turbulence. In the experiment, bubbles and solid particles are optically tracked in a turbulent flow of water using an…

Chaotic Dynamics · Physics 2008-08-28 R. Volk , E. Calzavarini , G. Verhille , D. Lohse , N. Mordant , J. -F. Pinton , F. Toschi

Existing video frame interpolation (VFI) methods blindly predict where each object is at a specific timestep t ("time indexing"), which struggles to predict precise object movements. Given two images of a baseball, there are infinitely many…

Computer Vision and Pattern Recognition · Computer Science 2026-03-03 Zhihang Zhong , Yiming Zhang , Wei Wang , Xiao Sun , Yu Qiao , Gurunandan Krishnan , Sizhuo Ma , Jian Wang

We theoretically analyze the effect of density/refractive-index gradients on the measurement precision of Volumetric Particle Tracking Velocimetry (V-PTV) and Background Oriented Schlieren (BOS) experiments by deriving the Cramer-Rao lower…

Fluid Dynamics · Physics 2020-06-24 Lalit K. Rajendran , Sally P. M. Bane , Pavlos P. Vlachos

Average precision (AP) is a widely used metric to evaluate detection accuracy of image and video object detectors. In this paper, we analyze object detection from videos and point out that AP alone is not sufficient to capture the temporal…

Computer Vision and Pattern Recognition · Computer Science 2019-11-11 Huizi Mao , Xiaodong Yang , William J. Dally

The Fast Multipole Method (FMM) offers an acceleration for pairwise interaction calculation, known as $N$-body problems, from $\mathcal{O}(N^2)$ to $\mathcal{O}(N)$ with $N$ particles. This has brought dramatic increase in the capability of…

Data Structures and Algorithms · Computer Science 2011-09-21 Felipe A. Cruz , L. A. Barba