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Optical Flow Estimation with Channel Constancy [chapter]

Laura Sevilla-Lara, Deqing Sun, Erik G. Learned-Miller, Michael J. Black
2014 Lecture Notes in Computer Science  
To address this we decompose images using a channel representation (CR) and replace the standard brightness constancy assumption with a descriptor constancy assumption.  ...  Our method estimates more accurate flow than the baseline on the MPI-Sintel benchmark, especially for fast motions and near motion boundaries.  ...  Optical Flow Estimation with Channel Constancy  ... 
doi:10.1007/978-3-319-10590-1_28 fatcat:543p5qcyvfdczjiamxsmitnpvi

Improved Confidence Measures for Variational Optical Flow

Maren Brumm, Jan Marek Marcinczak, Rolf-Rainer Grigat
2015 Proceedings of the 10th International Conference on Computer Vision Theory and Applications  
However, relatively few effort has been made to obtain robust confidence measures for the estimated flow field.  ...  In the last decades variational optical flow algorithms have been intensively studied by the computer vision community.  ...  To see whether it has an influence which data term is used for the optical flow calculation, the same evaluation is made for the optical flow field calculated with a constancy assumption on the grey values  ... 
doi:10.5220/0005167203890394 dblp:conf/visapp/BrummMG15 fatcat:beivqdrxxnfnxc5dzc3yrtsmii

Robust Optical Flow Estimation in Rainy Scenes [article]

Ruoteng Li, Robby T. Tan, Loong-Fah Cheong
2017 arXiv   pre-print
To our knowledge, this is the first optical flow method specifically dealing with rain.  ...  Optical flow estimation in the rainy scenes is challenging due to background degradation introduced by rain streaks and rain accumulation effects in the scene.  ...  We have introduced a robust algorithm for optical flow estimation in rainy scenes.  ... 
arXiv:1704.05239v2 fatcat:uizytgwoxza75fjpxmrcj4jc6e

On improving the robustness of variational optical flow against illumination changes

Mahmoud A. Mohamed, Hatem H. Rashwan, Bärbel Mertsching, Miguel Angel Garcia, Domenec Puig
2013 Proceedings of the 4th ACM/IEEE international workshop on Analysis and retrieval of tracked events and motion in imagery stream - ARTEMIS '13  
The brightness constancy assumption is the base of estimating the flow fields in most differential optical flow approaches.  ...  However, the brightness constancy constraint easily violates with any variation in the lighting conditions in the scene.  ...  INTRODUCTION Optical flow allows the estimation of the apparent motion of the scene.  ... 
doi:10.1145/2510650.2510660 dblp:conf/mm/MohamedRMGP13 fatcat:3ypxuvrpfvbl3kuoy5hgufs3mu

Motion Vector Field Estimation Using Brightness Constancy Assumption and Epipolar Geometry Constraint

S. Hosseinyalamdary, A. Yilmaz
2014 ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
The results show the improvement in motion vector field estimation in comparison to the Lucas-Kanade optical flow estimation.  ...  Among many, the Lucas-Kanade optical flow estimation has been employed for tracking interest points as well as motion vector field estimation.  ...  brightness constancy assumption Optical flow estimation is based on the brightness (or color) constancy assumption.  ... 
doi:10.5194/isprsannals-ii-1-9-2014 fatcat:en64z3wo45e2fbikyto3vymqfu

Optical Flow via Locally Adaptive Fusion of Complementary Data Costs

Tae Hyun Kim, Hee Seok Lee, Kyoung Mu Lee
2013 2013 IEEE International Conference on Computer Vision  
From these chosen data models, a new optical flow estimation energy model is designed with the weighted sum of the multiple data models, and a convex optimization-based highly effective and practical solution  ...  Many state-of-the-art optical flow estimation algorithms optimize the data and regularization terms to solve ill-posed problems.  ...  Therefore, our proposed optical flow estimation method is also based on the variational framework with a robust data term and regularizer.  ... 
doi:10.1109/iccv.2013.415 dblp:conf/iccv/KimLL13 fatcat:7vbfwnfgovdwtidx5lefyufmmq

High Accuracy Optical Flow for 3D Medical Image Registration Using the Census Cost Function [chapter]

Simon Hermann, René Werner
2014 Lecture Notes in Computer Science  
In 2004, Brox et al. described how to minimize an energy functional for dense 2D optical flow estimation that enforces both intensity and gradient constancy.  ...  Results show that the presented algorithm can compete with current state-of-the-art methods in regards to both registration accuracy and run-time.  ...  Furthermore, we replace the energy part that enforces intensity constancy with an arbitrary residual, similar to Müller et al., who introduced such a term for coupled convex optical flow approaches [13  ... 
doi:10.1007/978-3-642-53842-1_3 fatcat:dosio223dff7jlsdpcxfexx22e

Complementary Optic Flow [chapter]

Henning Zimmer, Andrés Bruhn, Joachim Weickert, Levi Valgaerts, Agustín Salgado, Bodo Rosenhahn, Hans-Peter Seidel
2009 Lecture Notes in Computer Science  
We introduce the concept of complementarity between data and smoothness term in modern variational optic flow methods.  ...  First we design a sophisticated data term that incorporates HSV colour representation with higher order constancy assumptions, completely separate robust penalisation, and constraint normalisation.  ...  It can be justified by the distinct information content of each of the three channels that drives the optic flow estimation in different ways. Final Data Term.  ... 
doi:10.1007/978-3-642-03641-5_16 fatcat:pndajjm5mvhdtcfmylbg3l6dau

Optic Flow in Harmony

Henning Zimmer, Andrés Bruhn, Joachim Weickert
2011 International Journal of Computer Vision  
This is achieved by using constraint normalisation, and an HSV colour representation with higher order constancy assumptions and a separate robust penalisation.  ...  The benefits of our "optic flow in harmony" (OFH) approach are demonstrated by an extensive experimental validation and by a competitive performance at the widely used Middlebury optic flow benchmark.  ...  This can be justified by the distinct information content of each of the three channels, see Fig. 2 , that drives the optic flow estimation in different ways.  ... 
doi:10.1007/s11263-011-0422-6 fatcat:xwaj5luye5agho5n7sdsrkrfbu

Variational Motion Segmentation with Level Sets [chapter]

Thomas Brox, Andrés Bruhn, Joachim Weickert
2006 Lecture Notes in Computer Science  
It need not fear a quantitative comparison to pure optic flow estimation techniques: For the popular Yosemite sequence with clouds we obtain the currently most accurate result.  ...  We suggest a variational method for the joint estimation of optic flow and the segmentation of the image into regions of similar motion.  ...  ., it is tested how well the estimated optic flow fits the constancy assumptions.  ... 
doi:10.1007/11744023_37 fatcat:dw2cs3gcj5c7tlsfmvtuoaioam

Local Estimation of High Velocity Optical Flow with Correlation Image Sensor [chapter]

Hidekata Hontani, Go Oishi, Tomohiro Kitagawa
2014 Lecture Notes in Computer Science  
When images are captured by conventional image sensors, the problem of the optical flow estimation is illposed if only the temporal constancy of the image brightness is the valid assumption.  ...  In this article, the authors address a problem of the estimation of high velocity optical flow.  ...  Making Optical Flow Problem Well-Posed The optical flow estimation is an ill-posed problem if a conventional image sensor is used and if only the temporal constancy is the valid assumption.  ... 
doi:10.1007/978-3-319-10578-9_16 fatcat:dogg2gm3ybanfh2vomcjz73sua

Back to Event Basics: Self-Supervised Learning of Image Reconstruction for Event Cameras via Photometric Constancy [article]

F. Paredes-Vallés, G. C. H. E. de Croon
2021 arXiv   pre-print
Our method, which leverages the knowledge of the inner workings of event cameras, combines estimated optical flow and the event-based photometric constancy to train neural networks without the need for  ...  Additionally, we propose a novel, lightweight neural network for optical flow estimation that achieves high speed inference with only a minor drop in performance.  ...  [14] , we simultaneously estimate intensity and optical flow from the input events.  ... 
arXiv:2009.08283v2 fatcat:kwrxetbhd5arlaioq7vvypfpym

Jointly Optical Flow and Occlusion Estimation for Images with Large Displacements

Vanel Lazcano, Luis Garrido, Coloma Ballester
2018 Proceedings of the 13th International Joint Conference on Computer Vision, Imaging and Computer Graphics Theory and Applications  
This paper deals with motion estimation of objects in a video sequence. This problem is known as optical flow estimation.  ...  Traditional models to estimate it fail in presence of occlusions and non-uniform illumination. To tackle these problems we propose a variational model to jointly estimate optical flow and occlusions.  ...  Jointly Optical Flow and Occlusion Estimation for Images with Displacements Proposition 3. Let 0 < τ ψ τ χ < 1/8.  ... 
doi:10.5220/0006716305880595 dblp:conf/visapp/LazcanoGB18 fatcat:n3za7dr27fgolno2yvsr42bp6e

A Survey on Variational Optic Flow Methods for Small Displacements [chapter]

Joachim Weickert, Andrés Bruhn, Thomas Brox, Nils Papenberg
2006 Mathematics in Industry  
Optic flow describes the displacement field in an image sequence.  ...  Variational methods recover the optic flow field as a minimiser of a suitable energy functional that involves data and smoothness terms.  ...  (b) Top right: Computed optic flow magnitude for a spatial approach with data term M 1 (brightness constancy) and smoothness term S 1 (homogeneous regularisation).  ... 
doi:10.1007/978-3-540-34767-5_5 fatcat:dojbj3vm6fa3tc4w5evrlnvhse

Nonrigid Optical Flow Ground Truth for Real-World Scenes With Time-Varying Shading Effects

Wenbin Li, Darren Cosker, Zhihan Lv, Matthew Brown
2017 IEEE Robotics and Automation Letters  
We also evaluate our hybrid optical flow algorithm by comparing to two existing multispectral approaches, as well as varying our input channels across RGB, NIR and RGB-NIR.  ...  A public evaluation website is constructed to allow for ranking of RGB image based optical flow and other dense tracking algorithms, with various statistical measures.  ...  RGB-NIR) for optical flow estimation. II.  ... 
doi:10.1109/lra.2016.2592513 dblp:journals/ral/0002CLB17 fatcat:njszkohgzja2rcvgpivwgkayeu
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