Filters








157,130 Hits in 3.5 sec

Symmetrical Dense Optical Flow Estimation with Occlusions Detection

Luis Alvarez, Rachid Deriche, Théo Papadopoulo, Javier Sánchez
2007 International Journal of Computer Vision  
Traditional techniques of dense optical flow estimation don't generally yield symmetrical solutions: the results will differ if they are applied between images I1 and I2 or between images I2 and I1.  ...  Promising experimental results on both synthetic and real images are presented to illustrate the capabilities of this symmetrical variational approach to recover accurate optical flow.  ...  Symmetric Optical Flow Let us first assume that the function h 2 is known.  ... 
doi:10.1007/s11263-007-0041-4 fatcat:tjml2445svdbdpk3hzfhmbczz4

Motion Compensated Frame Interpolation with a Symmetric Optical Flow Constraint [chapter]

Lars Lau Rakêt, Lars Roholm, Andrés Bruhn, Joachim Weickert
2012 Lecture Notes in Computer Science  
In this paper we illustrate its advantages by considering the classic TV-L 1 optical flow algorithm as a prototype.  ...  We propose to move the motion estimation from the surrounding frames directly to the unknown frame by parametrizing the optical flow objective function such that the interpolation assumption is directly  ...  The most obvious extension would be to use the symmetric data term with a more advanced optical flow method.  ... 
doi:10.1007/978-3-642-33179-4_43 fatcat:j5kwit5grnd5ziwz7ahivmwywu

SDOF-GAN: Symmetric Dense Optical Flow Estimation With Generative Adversarial Networks

Tongtong Che, Yuanjie Zheng, Yunshuai Yang, Sujuan Hou, Weikuan Jia, Jie Yang, Chen Gong
2021 IEEE Transactions on Image Processing  
We bridge this gap by introducing a novel model named SDOF-GAN: symmetric dense optical flow with generative adversarial networks (GANs).  ...  In addition, SDOF-GAN leverages a GAN model for which the generator estimates symmetric optical flow fields while the discriminator differentiates the "real" ground-truth flow field from a "fake" estimation  ...  For optical flow estimation, a symmetric optical flow method [4] has been proposed to estimate the flow field symmetrically via using a combination of the flows in both directions.  ... 
doi:10.1109/tip.2021.3084073 fatcat:3vsqjzcqyff6zjzkqfkbkgjqt4

Multi-image Interpolation based on Graph-Cuts and Symmetric Optic Flow [article]

Christian Linz, Christian Lipski, Marcus A. Magnor
2010 International Symposium on Vision, Modeling, and Visualization  
Combined with a symmetrical long-range optical flow formulation for correspondence field estimation, our approach yields crisp interpolated images without ghosting artifacts.  ...  [IK08] simultaneously estimate optical flow and occluded regions in a variational framework.  ...  [ADPS07] enforce symmetrical flow fields in a variational framework. They do not explicitly handle flow in occluded regions, but only impose a higher penalty on them.  ... 
doi:10.2312/pe/vmv/vmv10/115-122 dblp:conf/vmv/LinzLM10 fatcat:emtoqptruvbllo7hpgfk2nzscu

Multi-image interpolation based on graph-cuts and symmetric optical flow

Christian Linz, Christian Lipski, Marcus A. Magnor
2010 ACM SIGGRAPH 2010 Posters on - SIGGRAPH '10  
Combined with a symmetrical long-range optical flow formulation for correspondence field estimation, our approach yields crisp interpolated images without ghosting artifacts.  ...  ., perfect correspondence comes for free by symmetry of paths; in our approach we enforce symmetric correspondence fields by adapting the long-range correspondence estimation algorithm by Steinbruecker  ... 
doi:10.1145/1836845.1836983 dblp:conf/siggraph/LinzLM10 fatcat:sf3aiyam7fbgpgfb6fr6monydq

On Optical Measurements of Temperature Distributions of Axi-Symmetric Gas Flows
軸対称気流温度分布の光学的測定について

Kazuyoshi FUKUSAWA
1963 Journal of the Society of Mechanical Engineers  
Wolf , Principles of Optics, ( 1959), 88, Pergamon . (4 ) 日 高 ,応 用 積 分 万 程 式 諭 ,(昭 18), 229, 河 出書 房 . (5 ) G , H .  ... 
doi:10.1299/jsmemag.66.539_1733 fatcat:kotfpq3a5rhmfaj5rag25zc2fy

Symmetric Optical Flow [chapter]

L. Alvarez, C. A. Castaño, M. García, K. Krissian, L. Mazorra, A. Salgado, J. Sánchez
Computer Aided Systems Theory – EUROCAST 2007  
We propose a new symmetric variational formulation of the optical flow problem, where the flow is naturally symmetric.  ...  Results on the Yosemite sequence show an improved accuracy of our symmetric flow with respect to standard optical flow algorithm.  ...  We propose a new symmetric variational formulation of the optical flow problem, where the flow is naturally symmetric.  ... 
doi:10.1007/978-3-540-75867-9_85 dblp:conf/eurocast/AlvarezCGKMSS07b fatcat:s2iieo3bpnaqfeyqno3glnkq5m

Accuracy of eight deformable image registration (DIR) methods for tomotherapy megavoltage computed tomography (MVCT) images

Wannapha Nobnop, Hudsaleark Neamin, Imjai Chitapanarux, Somsak Wanwilairat, Vicharn Lorvidhaya, Taweap Sanghangthum
2017 Journal of Medical Radiation Sciences  
The symmetric transformation with Optical Flow showed good agreement for tissue-tissue interface areas with a CC of (0.99 AE 0.01) and DSC of (0.89 AE 0.03).  ...  The eight DIR methods used in the DIRART software varied in (i) transformation framework (asymmetric or symmetric), (ii) DIR registration algorithm (Demons or Optical Flow) and (iii) mapping direction  ...  and forward mapping; Sym-OF BW , symmetric transformation with the Horn and Schunck optical flow algorithm and backward mapping; Sym-OF FW , symmetric transformation with the Horn and Schunck optical  ... 
doi:10.1002/jmrs.236 pmid:28755425 pmcid:PMC5715263 fatcat:47xoonysgbdelcoqwb7ot6n5um

3D fluidic lens shaping—A multiconvex hydrodynamically adjustable optofluidic microlens

Michael Rosenauer, Michiel J. Vellekoop
2009 Lab on a Chip  
The sample distribution is no longer symmetrical to the optical axis and secondly the optical axis is shifted to the outlet by 190 µm.  ...  Fig. 1S Fluidic simulations of two expansion chamber designs at different flow rates. The symmetrical design shows good flow symmetry at low flow velocities.  ...  The sample distribution is no longer symmetrical to the optical axis and secondly the optical axis is shifted to the outlet by 190 µm.  ... 
doi:10.1039/b822981c pmid:19350083 fatcat:xqhhq6oegzhb5htyvqxzadcbka

'Lissajous-like' trajectories in optical tweezers

R. F. Hay, G. M. Gibson, S. H. Simpson, M. J. Padgett, D. B. Phillips
2015 Optics Express  
In this work we study the 'Lissajous-like' trajectories of an optically trapped 'probe' microsphere as it is subjected to timevarying oscillatory hydrodynamic flow-fields created by a nearby moving particle  ...  This symmetry breaking results in a fluidpumping effect, which arises due to the action of both a time-dependent hydrodynamic flow and a position-dependent optical restoring force, which together determine  ...  The actuator's trajectory is not symmetric upon time-reversal, and therefore the cycle-averaged flow-field it creates is non-zero.  ... 
doi:10.1364/oe.23.031716 pmid:26698964 fatcat:n3ikwtm5v5axlh72yjxnegzznu

Symmetric Velocity Structure in the SiO Maser Spectrum of R Cassiopeiae

P. R. Schwartz
1977 Publications of the Astronomical Society of the Pacific  
In the symmetric model for R Cas, V* ~ 26 km s -1 v=l 22.0, 27.0 u (km Fig. 2 -R Cas radial velocities as a function of radius for (a) symmetric model and a pulsation driven flow, and (b) symmetric model  ...  While this geometry is not physically excluded, it is certainly less plausible than the symmetric model with a pulsation driven flow.  ... 
doi:10.1086/130210 fatcat:aazkcse3yrbcdkog5axn2urfju

Nonlinear localized modes inPT-symmetric Rosen-Morse potential wells

Bikashkali Midya, Rajkumar Roychoudhury
2013 Physical Review A. Atomic, Molecular, and Optical Physics  
The transverse power flow density associated with these localized modes has also been examined.  ...  We report the existence and properties of localized modes described by nonlinear Schroedinger equation with complex PT-symmetric Rosen-Morse potential well.  ...  Existence of optical solitons in PT -symmetric nonlinear couplers with gain/loss [37, 38] , gap solitons in PT -symmetric optical lattices [39] and optical defect modes in PT -symmetric potentials  ... 
doi:10.1103/physreva.87.045803 fatcat:m5ptua5rrrefhb65mlzbrsasuu

Cryogenic temperature measurement of THz meta-resonance in symmetric metamaterial superlattice

J. H. Woo, E. S. Kim, Boyoung Kang, E. Y. Choi, Hyun-Hee Lee, J. Kim, Y. U. Lee, Tae Y. Hong, Jae H. Kim, J. W. Wu
2011 2011 International Quantum Electronics Conference (IQEC) and Conference on Lasers and Electro-Optics (CLEO) Pacific Rim incorporating the Australasian Conference on Optics, Lasers and Spectroscopy and the Australian Conference on Optical Fibre Technology  
We investigated a change in the Q-factor of THz meta-resonance as a function of temperature in a symmetric metamaterial superlattice composed by double-split ring resonators (DSRR).  ...  From the FDTD simulation we found that counter-flowing current densities among the nearest neighboring metaparticles cancel each other, resulting in the excitation of a trapped mode in meta-resonance.  ...  In this paper, we propose a symmetric metamaterial superlattice composed of symmetric DSRRs in a symmetric array to excite trapped mode.  ... 
doi:10.1109/iqec-cleo.2011.6193869 fatcat:ucvwxyrpofcgtj665tkyhnvvfy

Distinctive Optofluidic Parallel Waveguides

L.K. Chin, Y. Yang, L. Lei, A.Q. Liu
2014 Procedia Engineering  
For symmetrical waveguides, the core flow streams have a refractive index of 1.333 and the surrounding flow stream has a refractive index of 1.332.  ...  For symmetrical optofluidic parallel waveguides, both core flow streams have the same refractive index of 1.333 (dilute ethanol-DI water solution), and the surrounding flow stream has a refractive index  ... 
doi:10.1016/j.proeng.2014.11.595 fatcat:kbixuqg7kjf57nkblavxxy3a7u

On Convergence of the Horn and Schunck Optical-Flow Estimation Method

A. Mitiche, A.-R. Mansouri
2004 IEEE Transactions on Image Processing  
The purpose of this study is to prove convergence results for the Horn and Schunck optical-flow estimation method. Horn and Schunck stated optical-flow estimation as the minimization of a functional.  ...  We write explicitly this system and order the equations in such a way that its matrix is symmetric positive definite.  ...  optical-flow estimation method.  ... 
doi:10.1109/tip.2004.827235 pmid:15648874 fatcat:wqaeknzfnjg5bhu2zufjuzpyoq
« Previous Showing results 1 — 15 out of 157,130 results