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Unsupervised Deep Epipolar Flow for Stationary or Dynamic Scenes [article]

Yiran Zhong, Pan Ji, Jianyuan Wang, Yuchao Dai, Hongdong Li
2022 arXiv   pre-print
To alleviate a "chicken-and-egg" type of problem encountered in dynamic scenes where multiple motions may be present, we propose a low-rank constraint as well as a union-of-subspaces constraint for training  ...  Most existing deep-net based methods rely on image brightness consistency and local smoothness constraint to train the networks.  ...  This is achieved by introducing soft epipolar constraints derived from epipolar geometry, using low-rankness and union-of-subspaces properties.  ... 
arXiv:1904.03848v2 fatcat:ec5n5wdkmbbrjfsnmxmlf4vpgi

Trajectory reconstruction for affine structure-from-motion by global and local constraints

Hanno Ackermann, Bodo Rosenhahn
2009 2009 IEEE Conference on Computer Vision and Pattern Recognition  
This amounts to imposing a global constraint on the data. Secondly, we propose to further include local constraints derived from epipolar geometry into the estimation.  ...  It is shown how to simultaneously optimize both constraints. By using simulated and real image sequences we show the improvements achieved with our algorithm.  ...  The classic approach is to first establish correspondences between feature points in the images and then to compute the structure of the object and the motion of the camera by these correspondences.  ... 
doi:10.1109/cvpr.2009.5206664 dblp:conf/cvpr/AckermannR09 fatcat:rebbhc5esrgsvezyvyhgxa6tke

Trajectory reconstruction for affine structure-from-motion by global and local constraints

H. Ackermann, B. Rosenhahn
2009 2009 IEEE Conference on Computer Vision and Pattern Recognition  
This amounts to imposing a global constraint on the data. Secondly, we propose to further include local constraints derived from epipolar geometry into the estimation.  ...  It is shown how to simultaneously optimize both constraints. By using simulated and real image sequences we show the improvements achieved with our algorithm.  ...  The classic approach is to first establish correspondences between feature points in the images and then to compute the structure of the object and the motion of the camera by these correspondences.  ... 
doi:10.1109/cvprw.2009.5206664 fatcat:w7kyd5p3kfbjtdklxvk2pf7mty

Projective Reconstruction from Incomplete Trajectories by Global and Local Constraints

H. Ackermann, B. Rosenhahn
2011 2011 Conference for Visual Media Production  
The paper deals with projective shape and motion reconstruction by subspace iterations.  ...  By synthetic and real image sequences with up to 60% missing data we demonstrate that our algorithm is accurate and reliable.  ...  Introduction We consider the estimation of 3D structure and motion of a rigid object from multiple images given only point correspondences if both intrinsic and extrinsic parameters of the cameras are  ... 
doi:10.1109/cvmp.2011.15 dblp:conf/cvmp/AckermannR11 fatcat:5nvwkxh5kzh4pcynjugoonh6pi

Motion segmentation based on factorization method and discriminant criterion

N. Ichimura
1999 Proceedings of the Seventh IEEE International Conference on Computer Vision  
Experimental results are shown for synthetic data and real image sequences.  ...  A motion segmentation algorithm based on factorization method and discriminant criterion is proposed.  ...  This could be detected from entities of the fundamental matrix. (a) (b) Figure 9 : Epipolar constraints for a robot arm image sequence. (a),(b) Epipolar constraints for the first group.  ... 
doi:10.1109/iccv.1999.791279 dblp:conf/iccv/Ichimura99 fatcat:k5r7jxprirgb3g2zejy2cwu6vm

Self-Supervised Learning of Depth and Ego-Motion from Video by Alternative Training and Geometric Constraints from 3D to 2D [article]

Jiaojiao Fang, Guizhong Liu
2021 arXiv   pre-print
Self-supervised learning of depth and ego-motion from unlabeled monocular video has acquired promising results and drawn extensive attention.  ...  Most existing methods jointly train the depth and pose networks by photometric consistency of adjacent frames based on the principle of structure-from-motion (SFM).  ...  from Video by Alternative Training and Geometric Constraints from 3D to 2D Jiaojiao Fang, Guizhong Liu D subspaces, for depth and pose learning.  ... 
arXiv:2108.01980v1 fatcat:asc3s2iifzewlprbodmkcmqjzi

Using In-frame Shear Constraints for Monocular Motion Segmentation of Rigid Bodies

Siddharth Tourani, K Madhava Krishna
2015 Journal of Intelligent and Robotic Systems  
As a result a large number of the recently proposed motion segmentation algorithms model the problem as one of clustering the trajectory data to its corresponding affine subspace.  ...  Within a robotics and autonomous vehicle setting, the relative configuration of the robot and moving object will frequently be degenerate leading to a failure of subspace clustering algorithms.  ...  views, by extending the epipolar constraint and its corresponding fundamental matrix to the multi-body setting [40] .  ... 
doi:10.1007/s10846-015-0195-1 fatcat:hi4turtl2fb33bumoatedya7ei

Robust Multi-Body Feature Tracker: A Segmentation-Free Approach

Pan Ji, Hongdong Li, Mathieu Salzmann, Yiran Zhong
2016 2016 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)  
A conventional approach to addressing this problem would consist of alternating between solving two subtasks: motion segmentation and feature tracking under rigidity constraints for each segment.  ...  By contrast, here, we introduce a segmentationfree solution to multi-body feature tracking that bypasses the motion assignment step and reduces to solving a series of subproblems with closed-form solutions  ...  HL thanks the support of ARC grants DP120103896 and LP100100588, the ARC Centre of Excellence on Robotic Vision (CE140100016) and NICTA (Data61).  ... 
doi:10.1109/cvpr.2016.417 dblp:conf/cvpr/JiLSZ16 fatcat:q6ptvjzhgjfxjdj2ms4mehou7u

Two-View Multibody Structure from Motion

René Vidal, Yi Ma, Stefano Soatto, Shankar Sastry
2006 International Journal of Computer Vision  
We present an algebraic geometric approach to 3-D motion estimation and segmentation of multiple rigid-body motions from noise-free point correspondences in two perspective views.  ...  Keywords: Multibody structure from motion, 3-D motion segmentation, multibody epipolar constraint, multibody fundamental matrix and Generalized PCA (GPCA). * This paper is an extended version of [23] .  ...  Given n and F, we show that one can estimate the epipolar line associated with each correspondence from the first-order derivatives of the multibody epipolar constraint at the correspondence.  ... 
doi:10.1007/s11263-005-4839-7 fatcat:hqna3asy45d6neoswajboqvrcu

Robust Multi-body Feature Tracker: A Segmentation-free Approach [article]

Pan Ji, Hongdong Li, Mathieu Salzmann, Yiran Zhong
2016 arXiv   pre-print
A conventional approach to addressing this problem would consist of alternating between solving two subtasks: motion segmentation and feature tracking under rigidity constraints for each segment.  ...  By contrast, here, we introduce a segmentation-free solution to multi-body feature tracking that bypasses the motion assignment step and reduces to solving a series of subproblems with closed-form solutions  ...  Specifically, our approach bypasses the motion assignment step by making use of subspace constraints derived directly from the epipolar constraints of multiple motions.  ... 
arXiv:1603.00110v2 fatcat:nfrtfzbhmbbfrntzvqwqavvtwa

Robust Algebraic Segmentation of Mixed Rigid-Body and Planar Motions from Two Views

Shankar R. Rao, Allen Y. Yang, S. Shankar Sastry, Yi Ma
2010 International Journal of Computer Vision  
Based on the well-known epipolar and homography constraints between two views, we propose a hybrid perspective constraint (HPC) to unify the representation of rigidbody and planar motions.  ...  Given a mixture of K hybrid perspective constraints, we propose an algebraic process to partition image correspondences to the individual 3-D motions, called Robust Algebraic Segmentation (RAS).  ...  the original author(s) and source are credited.  ... 
doi:10.1007/s11263-009-0314-1 fatcat:5xuzrd7c4bbonbz6ceehpbvwga

Motion Segmentation by New Three-View Constraint from a Moving Camera

Fuyuan Xu, Guohua Gu, Kan Ren, Weixian Qian
2015 Mathematical Problems in Engineering  
The proposed method classifies each image pixel in the image sequence as the background or the motion regions by applying a novel three-view constraint called the "parallax-based multiplanar constraint  ...  Unlike the epipolar constraint, the parallax-based multiplanar constraint modifies the surface degradation to the line degradation to detect the motion objects followed by a moving camera in the same direction  ...  BK20130769, Jiangsu Province High-level Talents in Six Industries, no. 2012-DZXX-037, and Program for New Century Excellent Talents in University, no. NCET-12-0630.  ... 
doi:10.1155/2015/546580 fatcat:x5gzmtewxbft7bicxynjz7dnfu

What is computed by structure from motion algorithms? [chapter]

Cornelia Fermüller, Yiannis Aloimonos
1998 Lecture Notes in Computer Science  
The rst class contains techniques which require knowledge of the correspondence or the motion eld between the images and are based on the epipolar constraint.  ...  Speci cally, a general statistical model is employed to express the functions which measure the deviation from the epipolar constraint and the number of negative depth values, and these functions are studied  ...  The epipolar constraint then relates the corresponding image points through the underlying 3D motion 43] .  ... 
doi:10.1007/bfb0055678 fatcat:qdvhasrinvbcxfc6jwylybpa2u

Dynamic subspace-based coordinated multicamera tracking

Mustafa Ayazoglu, Binlong Li, Caglayan Dicle, Mario Sznaier, Octavia I. Camps
2011 2011 International Conference on Computer Vision  
epipolar constraints.  ...  This paper considers the problem of sustained multicamera tracking in the presence of occlusion and changes in the target motion model.  ...  epipolar constraints.  ... 
doi:10.1109/iccv.2011.6126531 dblp:conf/iccv/AyazogluLDSC11 fatcat:mcz2tdmuc5hqvgzjarj4b7elim

Detection of Independently Moving Objects in Non-planar Scenes via Multi-Frame Monocular Epipolar Constraint [chapter]

Soumyabrata Dey, Vladimir Reilly, Imran Saleemi, Mubarak Shah
2012 Lecture Notes in Computer Science  
Instead we utilize a multiframe monocular epipolar constraint of camera motion derived for monocular moving cameras defined by an evolving epipolar plane between the moving camera center and 3D scene points  ...  We use a combination of optical flow and particle advection to capture all motion in the video across a number of frames, in the form of particle trajectories.  ...  To do so we proposed a monocular multi-frame epipolar constraint, which we derived from an evolving epipolar plane defined by the motion of the center of the camera, and a scene point.  ... 
doi:10.1007/978-3-642-33715-4_62 fatcat:7k7ois2pord5zazio6bfvypgcy
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