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Tubular Anisotropy Segmentation [chapter]

Fethallah Benmansour, Laurent D. Cohen
2009 Lecture Notes in Computer Science  
Dans cet article, nous considérons le problème de la calibration géométrique dt'un projecteur vidéo à l'aide dt'un plan (mur) non marqué et dt'une caméra partiellement calibrés. Au lieu dt'utiliser des points de contrôle pour estimer lt'orientation mur-caméra, nous retrouvons cette relation en échantillonnant lt'hémisphère des orientations possibles. Ce processus est tellement rapide qut'il est même possible dt'intégrer lt'estimation de la focale de la caméra dans le processus
more » ... . Notre méthode est simple et donne de bons résultats tel que démontré par nos expérimentations. Mots Clef Calibration de projecteurs, calibration par plans, estimation de focal, vision active. Abstract In this paper we address the problem of geometric video projector calibration using a markerless planar surface (wall) and a partially calibrated camera. Instead of using control points to infer the camera-wall orientation, we find such relation by efficiently sampling the hemisphere of possible orientations. This process is so fast that even the focal of the camera can be estimated during the sampling process. Hence, physical grids and full knowledge of camera parameters are no longer necessary to calibrate a video projector.
doi:10.1007/978-3-642-02256-2_2 fatcat:lnea2o537vfmdojpkh6gp4mhhq

Tubular anisotropy for 2D vessel segmentation

Fethallah Benmansour, Laurent D. Cohen, Max W. K. Law, Albert C. S. Chung
2009 2009 IEEE Conference on Computer Vision and Pattern Recognition  
In this paper, we present a new approach for segmentation of tubular structures in 2D images providing minimal interaction.  ...  We have chosen to exploit the tubular structure of the vessels one wants to extract to built an anisotropic metric giving higher speed on the center of the vessels and also when the minimal path tangent  ...  Introduction In this paper we deal with the problem of finding a complete segmentation of tubular structures like vessels.  ... 
doi:10.1109/cvpr.2009.5206703 dblp:conf/cvpr/BenmansourCLC09 fatcat:4e5odurpfbfq7htqfbq2bbe4fm

Tubular anisotropy for 2D vessel segmentation

F. Benmansour, L.D. Cohen, M. Law, A. Chung
2009 2009 IEEE Conference on Computer Vision and Pattern Recognition  
In this paper, we present a new approach for segmentation of tubular structures in 2D images providing minimal interaction.  ...  We have chosen to exploit the tubular structure of the vessels one wants to extract to built an anisotropic metric giving higher speed on the center of the vessels and also when the minimal path tangent  ...  Introduction In this paper we deal with the problem of finding a complete segmentation of tubular structures like vessels.  ... 
doi:10.1109/cvprw.2009.5206703 fatcat:rak2tvsnonf57m4dj4k3fpwsnq

Minimal Paths for Tubular Structure Segmentation with Coherence Penalty and Adaptive Anisotropy [article]

Da Chen, Jiong Zhang, Laurent D. Cohen
2018 arXiv   pre-print
The minimal path method has proven to be particularly useful and efficient in tubular structure segmentation applications.  ...  The features that characterize the appearance and anisotropy properties of a tubular structure are extracted through the associated orientation score.  ...  For more models relevant to tubular structure segmentation, we refer to the complete reviews in [1] - [3] .  ... 
arXiv:1809.07987v3 fatcat:3p6454bgr5dhrc2dmy3w3d4c7q

A new interactive method for coronary arteries segmentation based on tubular anisotropy

Fethallah Benmansour, Laurent D. Cohen
2009 2009 IEEE International Symposium on Biomedical Imaging: From Nano to Macro  
We show results on two CT cardiac images for coronary arteries segmentation.  ...  In this paper we present a new interactive method for tubular structure extraction. The main application and motivation for this work is vessel tracking in 3D medical images.  ...  First two images : RCA segmentation using the tubular anisotropy approach shown on the whole image and on the selected sub-volume.  ... 
doi:10.1109/isbi.2009.5192978 dblp:conf/isbi/BenmansourC09 fatcat:b5rx4jmelnfvtfxmr3b4swqfsy

Susceptibility tensor imaging of the kidney and its microstructural underpinnings

Luke Xie, Russell Dibb, Gary P. Cofer, Wei Li, Peter J. Nicholls, G. Allan Johnson, Chunlei Liu
2014 Magnetic Resonance in Medicine  
Confocal microscopy was used to identify which tubular segments of the nephron were detected by DTI and STI. Results-Diffusion anisotropy was limited to the inner medulla of the kidney.  ...  DTI did not find a significant number of coherent tubular tracks in the outer medulla or cortex.  ...  We identified the tubular segments of the mouse nephron from confocal images of the same kidney used for MRI.  ... 
doi:10.1002/mrm.25219 pmid:24700637 pmcid:PMC4183741 fatcat:khc3wxh2lvgo3mep2yxkulcota

Simultaneous measurements of ionic currents, tension and optical properties of voltage clamped skeletal muscle fibres

J Poledna, L Lacinová
1988 General Physiology and Biophysics  
of the tubular mouth and lumen.  ...  The tension of the terminal segment of the fibre in the test compartment was measured isometrically.  ... 
pmid:2456248 fatcat:j2nck2ryzjbnldl7ficrsunlde

Tubular Structure Segmentation Based on Minimal Path Method and Anisotropic Enhancement

Fethallah Benmansour, Laurent D. Cohen
2010 International Journal of Computer Vision  
We have chosen to exploit the tubular structure of the vessels one wants to extract to built an anisotropic metric.  ...  We present a new interactive method for tubular structure extraction. The main application and motivation for this work is vessel tracking in 2D and 3D images.  ...  Fig. 17 17 First line : RCA segmentation using the tubular anisotropy approach shown on the whole image and on the selected sub-volume.  ... 
doi:10.1007/s11263-010-0331-0 fatcat:p3rbxglsvjhapai36ckfm2adnm

MRI tools for assessment of microstructure and nephron function of the kidney

Luke Xie, Kevin M. Bennett, Chunlei Liu, G. Allan Johnson, Jeff Lei Zhang, Vivian S. Lee
2016 AJP - Renal Physiology  
Quantitative MRI can assess local tubular function and is able to determine the concentrating mechanism of the kidney noninvasively in real time.  ...  Consequently, the presence of diffusion anisotropy and performance of DTI tractography indicate that the tubular segments are mostly intact.  ...  It treats nephron segments along the tubule as being distinct where tubular vectors are not projected or shared.  ... 
doi:10.1152/ajprenal.00134.2016 pmid:27630064 pmcid:PMC5210196 fatcat:ul67eb4whngmnbouzkipnwtqzu

ATP-Driven Exchange of Histone H2AZ Variant Catalyzed by SWR1 Chromatin Remodeling Complex

G. Mizuguchi
2004 Science  
Inferences on Flow at the Base of Earth's Mantle Based on Seismic Anisotropy Mark Panning* and Barbara Romanowicz We applied global waveform tomography to model radial anisotropy in the whole mantle.  ...  The bright segments are gold, and the dark domains are polypyrrole, corresponding to the diagram in the upper right inset.  ... 
doi:10.1126/science.1090701 pmid:14645854 fatcat:hed5g5x6cbfhtlufy5oexnaj34

Self-Assembly of Mesoscopic Metal-Polymer Amphiphiles

S. Park
2004 Science  
Inferences on Flow at the Base of Earth's Mantle Based on Seismic Anisotropy Mark Panning* and Barbara Romanowicz We applied global waveform tomography to model radial anisotropy in the whole mantle.  ...  The bright segments are gold, and the dark domains are polypyrrole, corresponding to the diagram in the upper right inset.  ... 
doi:10.1126/science.1093276 pmid:14726585 fatcat:wafaqywkjneffmn3s4zi7iggcq

Magnetic phase diagrams of barcode-type nanostructures

B Leighton, O J Suarez, P Landeros, J Escrig
2009 Nanotechnology  
In order to calculate the interaction energy between the ferromagnetic segments, we first need to calculate the magnetostatic potential U (r) of a single tubular structure.  ...  In order to calculate the interaction energy between the ferromagnetic segments, we first need to calculate the magnetostatic potential U (r) of a single tubular structure.  ... 
doi:10.1088/0957-4484/20/38/385703 pmid:19713575 fatcat:kkbeww6ecvc5hkkg5uwlqavnfa

Detecting tubular structures via direct vector field singularity characterization

Aytekin D Çabuk, E Alpay, B Acar
2010 2010 Annual International Conference of the IEEE Engineering in Medicine and Biology  
The initial step of vessel segmentation in 3D is the detection of vessel centerlines.  ...  In this paper we propose a 3D tubular structure detection method that removes these two drawbacks.  ...  Segmentation of tubular structures is composed of two major components: Centerline detection and surface segmentation.  ... 
doi:10.1109/iembs.2010.5628028 pmid:21097293 fatcat:7k4pfvqssbgf3e7kcr4slyhewa

Principal curves to extract vessels in 3D angiograms

Wilbur C. K. Wong, Albert C. S. Chung
2008 2008 IEEE Computer Society Conference on Computer Vision and Pattern Recognition Workshops  
Results show that it has high robustness to variation in image resolution, voxel anisotropy and noise.  ...  Segmentation of blood vessels and extraction of their centerlines in 3D angiography are essential to diagnosis and prognosis of vascular diseases, and advanced image processing and analysis.  ...  tubular structure and P i (x) is a similar function but with the segment projection set S replaced by a vertex projection set V.  ... 
doi:10.1109/cvprw.2008.4563015 dblp:conf/cvpr/WongC08 fatcat:dizhemy4izbodfyrzoewrzlnsm

Image contrast using the secondary and tertiary eigenvectors in diffusion tensor imaging

Jiangyang Zhang, Peter C.M. van Zijl, Susumu Mori
2006 Magnetic Resonance in Medicine  
Their usefulness in studying cellular events during brain development and tissue segmentation is assessed.  ...  Various anisotropy indices have been proposed to measure anisotropy of water diffusion, and V 1 has been used to reconstruct white matter structures.  ...  Their usefulness in studying cellular events during brain development and tissue segmentation is assessed.  ... 
doi:10.1002/mrm.20767 pmid:16402380 fatcat:recd73doc5fehdrucucrcppktm
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