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Displaying 1-28 out of 28 total
A Curved Ray Camera for Handling Occlusions through Continuous Multiperspective Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Jian Cui, Paul Rosen, Voicu Popescu, Christoph Hoffmann
Issue Date:November 2010
pp. 1235-1242
Most images used in visualization are computed with the planar pinhole camera. This classic camera model has important advantages such as simplicity, which enables efficient software and hardware implementations, and similarity to the human eye, which yiel...
 
Animated Depth Images for Interactive Remote Visualization of Time-Varying Data Sets
Found in: IEEE Transactions on Visualization and Computer Graphics
By Jian Cui,Zhiqiang Ma,Voicu Popescu
Issue Date:November 2014
pp. 1474-1489
Remote visualization has become both a necessity, as data set sizes have grown faster than computer network performance, and an opportunity, as laptop, tablet, and smartphone mobile computing platforms have become ubiquitous. However, the conventional remo...
 
The General Pinhole Camera: Effective and Efficient Nonuniform Sampling for Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Voicu Popescu, Paul Rosen, Laura Arns, Xavier Tricoche, Chris Wyman, Christoph M. Hoffmann
Issue Date:September 2010
pp. 777-790
We introduce the general pinhole camera (GPC), defined by a center of projection (i.e., the pinhole), an image plane, and a set of sampling locations in the image plane. We demonstrate the advantages of the GPC in the contexts of remote visualization, focu...
 
A High-Quality High-Fidelity Visualization of the September 11 Attack on the World Trade Center
Found in: IEEE Transactions on Visualization and Computer Graphics
By Paul Rosen, Voicu Popescu, Christoph Hoffmann, Ayhan Irfanoglu
Issue Date:July 2008
pp. 937-947
In this application paper we describe the efforts of a multi-disciplinary team towards producing a visualization of the September 11 Attack on the North Tower of New York?s World Trade Center. The visualization was designed to meet two requirements. First,...
 
Virtual Classroom Extension for Effective Distance Education
Found in: IEEE Computer Graphics and Applications
By Radu Dondera, Chun Jia, Voicu Popescu, Cristina Nita-Rotaru, Melissa Dark, Cynthia S. York
Issue Date:January 2008
pp. 64-74
Key requirements of effective distance learning are interactivity among participants and the student's sense of presence in the classroom. This system meets those requirements, letting the instructor perceive remote students' body language and facial expre...
 
The Soft Shadow Occlusion Camera
Found in: Computer Graphics and Applications, Pacific Conference on
By Qi Mo, Voicu Popescu, Chris Wyman
Issue Date:November 2007
pp. 189-198
A fundamental challenge for existing shadow map based algorithms is dealing with partially illuminated surfaces. A conventional shadow map built with a pinhole camera only determines a binary light visibility at each point, and this all-or-nothing approach...
 
Occlusion-Resistant Camera Design for Acquiring Active Environments
Found in: IEEE Computer Graphics and Applications
By Daniel G. Aliaga, Yi Xu, Voicu Popescu
Issue Date:September 2007
pp. 68-78
The authors propose a family of occlusion-resistant camera (ORC) designs for acquiring active environments despite the presence of moving interfering occluders. Capturing images in an in-use environment increases acquisition efficiency and quality without ...
 
An Efficient Error-Bounded General Camera Model
Found in: 3D Data Processing Visualization and Transmission, International Symposium on
By Voicu Popescu, Jordan Dauble, Chunhui Mei, Elisha Sacks
Issue Date:June 2006
pp. 121-128
Camera models are essential infrastructure in computer vision, computer graphics, and visualization. The most frequently used camera models are based on the single-viewpoint constraint. Removing this constraint brings the advantage of improved flexibility ...
 
Depth Enhanced Panoramas
Found in: Visualization Conference, IEEE
By Gleb Bahmutov, Voicu Popescu, Elisha Sacks
Issue Date:October 2004
pp. 11p
No summary available.
   
Modeling, Simulation, and Visualization: The Pentagon on September 11th
Found in: Computing in Science and Engineering
By Chris Hoffmann, Voicu Popescu, Sami Kilic, Mete Sozen
Issue Date:January 2004
pp. 52-60
<p>Researchers used a custom importer to simplify and load simulation data from the September 11th Pentagon attack into a commercial animation system. The resulting high-quality impact visualization combines state-of-the-art graphics with state-of-th...
 
The ModelCamera: a Hand-Held Device for Interactive Modeling
Found in: 3D Digital Imaging and Modeling, International Conference on
By Voicu Popescu, Elisha Sacks, Gleb Bahmutov
Issue Date:October 2003
pp. 285
An important goal of automated modeling is to provide computer graphics applications with high quality models of complex real-world scenes. Prior systems have one or more of the following disadvantages: slow modeling pipeline, applicability restricted to s...
 
Producing High-Quality Visualizations of Large-Scale Simulations
Found in: Visualization Conference, IEEE
By Voicu Popescu, Chris Hoffmann, Sami Kilic, Mete Sozen, Scott Meador
Issue Date:October 2003
pp. 76
This paper describes the work of a team of researchers in computer graphics, geometric computing, and civil engineering to produce a visualization of the September 2001 attack on the Pentagon. The immediate motivation for the project was to understand the ...
 
The Impact of Dense Range Data on Computer Graphics
Found in: Multi-View Modeling and Analysis of Visual Scenes, IEEE Workshop on
By Lars Nyland, David McAllister, Voicu Popescu, Chris McCue, Anselmo Lastra, Paul Rademacher, Manuel Oliveira, Gary Bishop, Gopi Meenakshisundaram, Matt Cutts, Henry Fuchs
Issue Date:June 1999
pp. 3
The ability to quickly acquire dense range data of familiar environments has been met with enthusiastic response in our graphics laboratory. In this paper, we describe our prototype range collection system, based on a scanning laser rangefinder and a high-...
 
Images for Accelerating Architectural Walkthroughs
Found in: IEEE Computer Graphics and Applications
By Matthew M. Rafferty, Daniel G. Aliaga, Voicu Popescu, Anselmo A. Lastra
Issue Date:November 1998
pp. 38-45
We are investigating methods to accelerate rendering of architectural walkthroughs. In this article, we improve upon a cells and portals framework by using images to replace geometry visible through portals (doors and windows) in a three-dimensional model....
 
The graph camera
Found in: ACM Transactions on Graphics (TOG)
By Nicoletta Adamo-Villani, Paul Rosen, Voicu Popescu, Nicoletta Adamo-Villani, Paul Rosen, Voicu Popescu
Issue Date:December 2009
pp. 1-2
A conventional pinhole camera captures only a small fraction of a 3-D scene due to occlusions. We introduce the graph camera, a non-pinhole with rays that circumvent occluders to create a single layer image that shows simultaneously several regions of inte...
     
Second-Order Feed-Forward Renderingfor Specular and Glossy Reflections
Found in: IEEE Transactions on Visualization and Computer Graphics
By Lili Wang,Naiwen Xie,Wei Ke,Voicu Popescu
Issue Date:September 2014
pp. 1-1
The feed-forward pipeline based on projection followed by rasterization handles the rays that leave the eye efficiently: these first-order rays are modeled with a simple camera that projects geometry to screen. Second-order rays however, as, for example, t...
 
A Flexible Pinhole Camera Model for Coherent Nonuniform Sampling
Found in: IEEE Computer Graphics and Applications
By Voicu Popescu,Bedrich Benes,Paul Rosen,Jian Cui,Lili Wang
Issue Date:July 2014
pp. 30-41
The flexible pinhole camera (FPC) allows flexible modulation of the sampling rate over the field of view. The FPC is defined by a viewpoint and a map specifying the sampling locations on the image plane. The map is constructed from known regions of interes...
 
Interactive Modeling from Dense Color and Sparse Depth
Found in: 3D Data Processing Visualization and Transmission, International Symposium on
By Voicu Popescu, Elisha Sacks, Gleb Bahmutov
Issue Date:September 2004
pp. 430-437
We present research in scene modeling. The task is to build digital models of natural scenes that support interactive, photorealistic rendering. Scene modeling is the bottleneck in many computer graphics applications, notably virtual training, geometric mo...
 
Efficient Warping for Architectural Walkthroughs Using Layered Depth Images
Found in: Visualization Conference, IEEE
By Voicu Popescu, Anselmo Lastra, Daniel Aliaga, Manual de Oliveira Neto
Issue Date:October 1998
pp. 211
This paper presents efficient image-based rendering techniques used in the context of an architectural walkthrough system. Portals (doors and windows) are rendered by warping layered depth images (LDIs). In a preprocessing phase, for every portal, a number...
 
The graph camera
Found in: ACM SIGGRAPH Asia 2009 papers (SIGGRAPH Asia '09)
By Nicoletta Adamo-Villani, Paul Rosen, Voicu Popescu
Issue Date:December 2009
pp. 1-6
A conventional pinhole camera captures only a small fraction of a 3-D scene due to occlusions. We introduce the graph camera, a non-pinhole with rays that circumvent occluders to create a single layer image that shows simultaneously several regions of inte...
     
The epipolar occlusion camera
Found in: Proceedings of the 2008 symposium on Interactive 3D graphics and games (SI3D '08)
By Paul Rosen, Voicu Popescu
Issue Date:February 2008
pp. 1-89
A depth image constructed with a pinhole camera suffers from disocclusion errors: even a minimal viewpoint translation exposes samples not visible from the original viewpoint. The conventional solution to employ additional depth images is inefficient. A re...
     
1001 acquisition viewpoints: efficient and versatile view-dependent modeling of real-world scenes
Found in: ACM SIGGRAPH 2007 sketches on XX (SIGGRAPH '07)
By Mihai Mudure, Voicu Popescu
Issue Date:August 2007
pp. 34-es
Constructing high-fidelity 3D models of real-world scenes is an important bottleneck for many computer graphics applications. Manual modeling using CAD or animation software requires artistic talent and a huge time investment. Automated modeling based on a...
     
A multi-expertise application-driven class
Found in: Proceedinds of the 38th SIGCSE technical symposium on Computer science education (SIGCSE '07)
By Cristina Nita-Rotaru, Melissa Dark, Voicu Popescu
Issue Date:March 2007
pp. 64-ff
In this paper we report on our experience of teaching a multi-expertise application-driven course in which upper-level undergraduate and entry-level graduate students from computer science, computer graphics technology, and educational science worked toget...
     
Efficient large scale acquisition of building interiors
Found in: ACM SIGGRAPH 2006 Sketches (SIGGRAPH '06)
By Gleb Bahmutov, Mihai Mudure, Voicu Popescu
Issue Date:July 2006
pp. 127-es
We describe the interactive demonstration 'Instant Replay' to be shown at the Emerging Technologies at Siggraph 2006. Instant Replay is an example application of an inexpensive, highly accurate 'motion capture' system that is able to effectively track many...
     
Efficient large scale acquisition of building interiors
Found in: Material presented at the ACM SIGGRAPH 2006 conference (SIGGRAPH '06)
By Gleb Bahmutov, Mihai Mudure, Voicu Popescu
Issue Date:July 2006
pp. 127-es
We describe the interactive demonstration 'Instant Replay' to be shown at the Emerging Technologies at Siggraph 2006. Instant Replay is an example application of an inexpensive, highly accurate 'motion capture' system that is able to effectively track many...
     
Forward rasterization
Found in: ACM Transactions on Graphics (TOG)
By Paul Rosen, Voicu Popescu
Issue Date:April 2006
pp. 375-411
We describe forward rasterization, a class of rendering algorithms designed for small polygonal primitives. The primitive is efficiently rasterized by interpolation between its vertices. The interpolation factors are chosen to guarantee that each pixel cov...
     
The depth discontinuity occlusion camera
Found in: Proceedings of the 2006 symposium on Interactive 3D graphics and games (SI3D '06)
By Daniel Aliaga, Voicu Popescu
Issue Date:March 2006
pp. 139-143
Rendering a scene using a single depth image suffers from disocclusion errors as the view translates away from the reference view. We present the depth discontinuity occlusion camera (DDOC), a non-pinhole camera that samples surfaces which are hidden in th...
     
The vacuum buffer
Found in: Proceedings of the 2001 symposium on Interactive 3D graphics (SI3D '01)
By Anselmo Lastra, Voicu Popescu
Issue Date:March 2001
pp. 73-76
we present an exact and interactive collision detection system, I-COLLIDE, for large-scale environments. Such environments are characterized by the number of objects undergoing rigid motion and the complexity of the models. The algorithm does not assume th...
     
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