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Displaying 1-17 out of 17 total
Tracking an RGB-D Camera Using Points and Planes
Found in: 2013 IEEE International Conference on Computer Vision Workshops (ICCVW)
By Esra Ataer-Cansizoglu,Yuichi Taguchi,Srikumar Ramalingam,Tyler Garaas
Issue Date:December 2013
pp. 51-58
Planes are dominant in most indoor and outdoor scenes and the development of a hybrid algorithm that incorporates both point and plane features provides numerous advantages. In this regard, we present a tracking algorithm for RGB-D cameras using both point...
 
Lifting 3D Manhattan Lines from a Single Image
Found in: 2013 IEEE International Conference on Computer Vision (ICCV)
By Srikumar Ramalingam,Matthew Brand
Issue Date:December 2013
pp. 497-504
We propose a novel and an efficient method for reconstructing the 3D arrangement of lines extracted from a single image, using vanishing points, orthogonal structure, and an optimization procedure that considers all plausible connectivity constraints betwe...
 
SLAM using both points and planes for hand-held 3D sensors
Found in: 2012 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)
By Yuichi Taguchi, Yong-Dian Jian,Srikumar Ramalingam, Chen Feng
Issue Date:November 2012
pp. 321-322
We present a simultaneous localization and mapping (SLAM) algorithm for a hand-held 3D sensor that uses both points and planes as primitives. Our algorithm uses any combination of three point/plane primitives (3 planes, 2 planes and 1 point, 1 plane and 2 ...
 
A theory of multi-layer flat refractive geometry
Found in: 2012 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
By Amit Agrawal,Srikumar Ramalingam,Yuichi Taguchi,Visesh Chari
Issue Date:June 2012
pp. 3346-3353
Flat refractive geometry corresponds to a perspective camera looking through single/multiple parallel flat refractive mediums. We show that the underlying geometry of rays corresponds to an axial camera. This realization, while missing from previous works,...
 
Axial light field for curved mirrors: Reflect your perspective, widen your view
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Yuichi Taguchi, Amit Agrawal, Srikumar Ramalingam, Ashok Veeraraghavan
Issue Date:June 2010
pp. 499-506
Mirrors have been used to enable wide field-of-view (FOV) catadioptric imaging. The mapping between the incoming and reflected light rays depends non-linearly on the mirror shape and has been well-studied using caustics. We analyze this mapping using two-p...
 
Minimal solutions for generic imaging models
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Srikumar Ramalingam, Peter Sturm
Issue Date:June 2008
pp. 1-8
A generic imaging model refers to a non-parametric camera model where every camera is treated as a set of unconstrained projection rays. Calibration would simply be a method to map the projection rays to image pixels; such a mapping can be computed using p...
 
Randomized trees for human pose detection
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Gregory Rogez, Jonathan Rihan, Srikumar Ramalingam, Carlos Orrite, Philip H.S. Torr
Issue Date:June 2008
pp. 1-8
This paper addresses human pose recognition from video sequences by formulating it as a classification problem. Unlike much previous work we do not make any assumptions on the availability of clean segmentation. The first step of this work consists in a no...
 
Exact inference in multi-label CRFs with higher order cliques
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Srikumar Ramalingam, Pushmeet Kohli, Karteek Alahari, Philip H. S. Torr
Issue Date:June 2008
pp. 1-8
This paper addresses the problem of exactly inferring the maximum a posteriori solutions of discrete multi-label MRFs or CRFs with higher order cliques. We present a framework to transform special classes of multi-label higher order functions to submodular...
 
Learning priors for calibrating families of stereo cameras
Found in: Computer Vision, IEEE International Conference on
By Andrew W. Fitzgibbon, Duncan P. Robertson, Antonio Criminisi, Srikumar Ramalingam, Andrew Blake
Issue Date:October 2007
pp. 1-8
Online camera recalibration is necessary for long-term deployment of computer vision systems. Existing algorithms assume that the source of recalibration information is a set of features in a general 3D scene; and that enough features are observed that the...
 
A Factorization Based Self-Calibration for Radially Symmetric Cameras
Found in: 3D Data Processing Visualization and Transmission, International Symposium on
By Srikumar Ramalingam, Peter Sturm, Edmond Boyer
Issue Date:June 2006
pp. 480-487
The paper proposes a novel approach for planar self-calibration of radially symmetric cameras. We model these camera images using notions of distortion center and concentric distortion circles around it. The rays corresponding to pixels lying on a single d...
 
Towards Complete Generic Camera Calibration
Found in: Computer Vision and Pattern Recognition, IEEE Computer Society Conference on
By Srikumar Ramalingam, Peter Sturm, Suresh K. Lodha
Issue Date:June 2005
pp. 1093-1098
We consider the problem of calibrating a highly generic imaging model, that consists of a non-parametric association of a projection ray in 3D to every pixel in an image. Previous calibration approaches for this model do not seem to be directly applicable ...
 
Adaptive Enhancement of 3D Scenes using Hierarchical Registration of Texture-Mapped 3D models
Found in: 3D Digital Imaging and Modeling, International Conference on
By Srikumar Ramalingam, Suresh K. Lodha
Issue Date:October 2003
pp. 203
Adaptive fusion of new information in a 3D urban scene is an important goal to achieve in computer vision, graphics, and visualization. In this work we acquire new image pairs of a scene from closer distances and extract 3D models of successively higher re...
 
Axial-cones: modeling spherical catadioptric cameras for wide-angle light field rendering
Found in: ACM Transactions on Graphics (TOG)
By Amit Agrawal, Ashok Veeraraghavan, Ramesh Raskar, Srikumar Ramalingam, Yuichi Taguchi, Amit Agrawal, Ashok Veeraraghavan, Ramesh Raskar, Srikumar Ramalingam, Yuichi Taguchi
Issue Date:December 2010
pp. 1-12
Catadioptric imaging systems are commonly used for wide-angle imaging, but lead to multi-perspective images which do not allow algorithms designed for perspective cameras to be used. Efficient use of such systems requires accurate geometric ray modeling as...
     
Entropy-Rate Clustering: Cluster Analysis via Maximizing a Submodular Function Subject to a Matroid Constraint
Found in: IEEE Transactions on Pattern Analysis and Machine Intelligence
By Ming-Yu Liu,Oncel Tuzel,Srikumar Ramalingam,Rama Chellappa
Issue Date:January 2014
pp. 99-112
We propose a new objective function for clustering. This objective function consists of two components: the entropy rate of a random walk on a graph and a balancing term. The entropy rate favors formation of compact and homogeneous clusters, while the bala...
 
Manhattan Junction Catalogue for Spatial Reasoning of Indoor Scenes
Found in: 2013 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
By Srikumar Ramalingam,Jaishanker K. Pillai,Arpit Jain,Yuichi Taguchi
Issue Date:June 2013
pp. 3065-3072
Junctions are strong cues for understanding the geometry of a scene. In this paper, we consider the problem of detecting junctions and using them for recovering the spatial layout of an indoor scene. Junction detection has always been challenging due to mi...
 
Single Image Calibration of Multi-axial Imaging Systems
Found in: 2013 IEEE Conference on Computer Vision and Pattern Recognition (CVPR)
By Amit Agrawal,Srikumar Ramalingam
Issue Date:June 2013
pp. 1399-1406
Imaging systems consisting of a camera looking at multiple spherical mirrors (reflection) or multiple refractive spheres (refraction) have been used for wide-angle imaging applications. We describe such setups as multi-axial imaging systems, since a single...
 
Axial-cones: modeling spherical catadioptric cameras for wide-angle light field rendering
Found in: ACM SIGGRAPH Asia 2010 papers (SIGGRAPH ASIA '10)
By Amit Agrawal, Ashok Veeraraghavan, Ramesh Raskar, Srikumar Ramalingam, Yuichi Taguchi
Issue Date:December 2010
pp. 20-21
Catadioptric imaging systems are commonly used for wide-angle imaging, but lead to multi-perspective images which do not allow algorithms designed for perspective cameras to be used. Efficient use of such systems requires accurate geometric ray modeling as...
     
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