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3D Motion Estimation Using a Combination of Correlation and Variational Methods for PIV [chapter]

L. Alvarez, C. A. Castaño, M. García, K. Krissian, L. Mazorra, A. Salgado, J. Sánchez
Computer Aided Systems Theory – EUROCAST 2007  
In this context, we propose a 3D motion estimation technique based on the combination of an iterative crosscorrelation technique and a variational (energy-based) technique.  ...  Estimation of motion has many applications in fluid analysis.  ...  We acknowledge the Research Institute CEMAGREF (France) for providing to us the PIV sequence we have used in the experiments.  ... 
doi:10.1007/978-3-540-75867-9_77 dblp:conf/eurocast/AlvarezCGKMSS07 fatcat:bmayuirhojb3nk4tefv7rzzzqi

3D + time blood flow mapping using SPIM-microPIV in the developing zebrafish heart

Vytautas Zickus, Jonathan M. Taylor
2018 Biomedical Optics Express  
SPIM-µPIV enables high quality in vivo measurements of flow fields that will be valuable for studies of heart function and fluid-structure interaction in a range of small-animal models.  ...  We present SPIM-µPIV as a flow imaging system, capable of measuring in vivo flow information with 3D micron-scale resolution.  ...  We thank Richard Hoppe for his contributions to studying the limitations of brightfield ÎijPIV. VZ is supported by a research training support grant from the EPSRC (EP/M506539/1).  ... 
doi:10.1364/boe.9.002418 pmid:29760998 pmcid:PMC5946799 fatcat:yjxxoe7xqnbyhev5zozjj4dd5q

Particle Image Velocimetry (PIV) Uncertainty Quantification Using Moment of Correlation (MC) Plane [article]

Sayantan Bhattacharya, John J. Charonko, Pavlos P. Vlachos
2018 arXiv   pre-print
We present a new uncertainty estimation method for Particle Image Velocimetry (PIV), that uses the correlation plane as a model for the probability density function (PDF) of displacements and calculates  ...  MC uses this property to estimate the PIV uncertainty from the shape of the cross-correlation plane.  ...  prediction tool and provides a framework to estimate cross-correlation uncertainty even in 3D crosscorrelation.  ... 
arXiv:1804.10854v1 fatcat:bivw7elx35bwnjsshdegtbtxse

Variational fluid flow measurements from image sequences: synopsis and perspectives

Dominique Heitz, Etienne Mémin, Christoph Schnörr
2009 Experiments in Fluids  
We outline promising research directions and point out the potential of variational techniques in combination with correlation-based PIV methods, for improving the consistency of fluid flow estimation  ...  Variational approaches to image motion segmentation has been an active field of study in image processing and computer vision for two decades.  ...  In order to benefit from the best properties of both variational dense estimators and correlation techniques, an immediate idea is to combine these two methods.  ... 
doi:10.1007/s00348-009-0778-3 fatcat:p2voujunsrdwxasipwp6ve5syq

A robust motion estimation algorithm for PIV

Mani Thomas, Shubhra Misra, Chandra Kambhamettu, James T Kirby
2005 Measurement science and technology  
The method is based on phase correlation, where the phase of the Fourier components is used for motion parameter estimation.  ...  The present study proposes an approach for robust estimation of the instantaneous motion field from a time lagged pair of PIV images.  ...  Acknowledgments Research funding was provided by the National Ocean Partnership Program (NOPP) N00014-99-1-1051 and National Science Foundation Grant CAREER IRI-9984842.  ... 
doi:10.1088/0957-0233/16/3/031 fatcat:6leiqgxsuzfevjemf4x5p6ernm

A variational approach for particle tracking velocimetry

P Ruhnau, C Guetter, T Putze, C Schnörr
2005 Measurement science and technology  
We introduce a novel variational approach for evaluating PTV image pairs and sequences in two and three dimensions.  ...  The experimental evaluation shows that our variational method competes with three alternative approaches. We outline the potential of our method for further developments.  ...  This method is considered a variation of the standard crosscorrelation PIV, in which the correlation functions are computed for each interrogation window which is centred on the first-frame particles.  ... 
doi:10.1088/0957-0233/16/7/007 fatcat:d64ehqzhevfmro4v43o5vybapq

Particle image velocimetry - Classical operating rules from today's perspective

Sven Scharnowski, Christian J. Kähler
2020 Optics and lasers in engineering  
Although time-resolved volumetric PIV measurements are possible today, the majority of measurements are still performed using planar PIV techniques for good reasons.  ...  First, planar PIV is rather simple to both install and use and the data is processed quickly and robustly.  ...  But for a reliable uncertainty quantification the methods must be calibrated and tested using synthetic PIV images or flows with know properties.  ... 
doi:10.1016/j.optlaseng.2020.106185 fatcat:l2jo6nbnhvgcfnuxyorf34bjiu

Limits in Planar PIV Due to Individual Variations of Particle Image Intensities [chapter]

Holger Nobach
2012 The Particle Image Velocimetry - Characteristics, Limits and Possible Applications  
All methods use 10 iteration and a velocity estimation grid of 8×8 pixels corresponding to 75 % overlap for 32×32 pixels windows and 50 % overlap for the 16×16 pixels window.  ...  The error has been quantified for several commonly used PIV processing methods.  ...  The book is aimed at presenting the PIV technique and its wide range of possible applications so as to provide a reference for researchers who intended to exploit this innovative technique in their research  ... 
doi:10.5772/34671 fatcat:536ymyksofbpvk6xjm2ynraahe

Variational 3D-PIV with sparse descriptors

Katrin Lasinger, Christoph Vogel, Thomas Pock, Konrad Schindler
2018 Measurement science and technology  
We propose a variational model, which makes it possible to directly include physical properties, such as incompressibility and viscosity, in the estimation of the motion field.  ...  The second step of 3D-PIV is to then recover the dense motion field from two consecutive particle reconstructions.  ...  Christoph Vogel and Thomas Pock acknowledge support from the ERC starting grant 640156, HOMOVIS. We thank Markus Holzner for discussions and help with the evaluation.  ... 
doi:10.1088/1361-6501/aab5a0 fatcat:n3lnrlgs2feenph4pexiztob6q

A robust videogrametric method for the velocimetry of wind-induced motion in trees

Adelin Barbacci, Julien Diener, Pascal Hémon, Boris Adam, Nicolas Donès, Lionel Reveret, Bruno Moulia
2014 Agricultural and Forest Meteorology  
Therefore, there is a crucial need for non-invasive methods to describe and quantify the complex motion of a plant induced by wind.  ...  An adaptation of the classical Particle Image Velocimetry method (nat-PIV) is compared with a tracking method based on the optical flow method of Lukas and Kanade, initialized with the features selection  ...  Chaleil for technical assistance with the tree experiments. Appendix A.  ... 
doi:10.1016/j.agrformet.2013.10.003 fatcat:hpkmb6qs7nbsxop3oqlqljtav4

Recent advances in digital particle image velocimetry methods for flow motion analysis

H. Nasibov, S. Baytaroglu
2010 International Journal of Metrology and Quality Engineering  
Due to recent advances in image processing methods, and in digital imaging, laser and optics DPIV has become a dominant tool for obtaining velocity information about fluid motion.  ...  The advent of charge-coupled devices (CCD) has significantly extended the horizons of full-field measurement methods in many fields of fundamental and applied sciences, including fluid flow dynamics.  ...  We would like to thank Omer Altan for proofreading and correcting the English manuscript.  ... 
doi:10.1051/ijmqe/2010007 fatcat:f2kfhsiqk5dppms32jpzswrf7u

Uncertainty quantification in particle image velocimetry

Andrea Sciacchitano
2019 Measurement science and technology  
Those are divided into a-priori UQ approaches, which provide a general figure for the uncertainty of PIV measurements, and a-posteriori UQ approaches, which are data-based and aim at quantifying the uncertainty  ...  particles, imaging of those, analysis of the particle motion, data validation and reduction.  ...  Acknowledgments Dr Bernhard Wieneke is kindly acknowledged for the many productive conversations about PIV-UQ and for his valuable comments on this manuscript.  ... 
doi:10.1088/1361-6501/ab1db8 fatcat:rapmgkgykzazzfok34kqby4vwy

OpenPIV-Matlab – An open-source software for particle image velocimetry; test case: birds' aerodynamics [article]

Hadar Ben Gida, Roi Gurka, Alex Liberzon
2020 arXiv   pre-print
We extend the PIV analysis with additional tools for post-processing the PIV results including the estimation of aero/hydrodynamic forces from the PIV data of a wake behind an immersed (bluff or streamlined  ...  A complete analysis with a variety of post-processing capabilities is demonstrated using time-resolved PIV wake data of a freely flying European starling (Sturnus vulgaris) in a wind tunnel.  ...  The open source software could not exist without the vibrant community of users and developers that contribute by their test cases, verification and validation studies, and of course software and documentation  ... 
arXiv:2007.12967v1 fatcat:7d72psp2sfcxhic54dhdtg7naq

Variational estimation of experimental fluid flows with physics-based spatio-temporal regularization

Paul Ruhnau, Annette Stahl, Christoph Schnörr
2007 Measurement science and technology  
We present a variational approach to motion estimation of instationary experimental fluid flows from image sequences.  ...  This allows for a recursive on-line (non-batch) implementation of our variational estimation framework.  ...  Acknowledgment The authors thank Johan Carlier (Cemagref) for providing the 2D image sequences and Rainer Hain (TU Braunschweig) for providing the cross-correlation estimates.  ... 
doi:10.1088/0957-0233/18/3/027 fatcat:r3u7syx63jewnks3y7olxjd6ta

3D Fluid Flow Estimation with Integrated Particle Reconstruction [article]

Katrin Lasinger, Christoph Vogel, Thomas Pock, Konrad Schindler
2018 arXiv   pre-print
The method exhibits greatly (~70%) improved results over a recent baseline with two separate steps for 3D reconstruction and motion estimation.  ...  We show, for the first time, how to jointly reconstruct both the individual tracer particles and a dense 3D fluid motion field from the image data, using an integrated energy minimization.  ...  [11] combine TomoPIV with variational 3D flow estimation and account for physical constraints, with a regularizer derived from the stationary Stokes equations.  ... 
arXiv:1804.03037v2 fatcat:b54rarbvgncwpittzcnljpooci
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