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Displaying 1-50 out of 69 total
A Magnification Lens for Interactive Volume Visualization
Found in: Computer Graphics and Applications, Pacific Conference on
By Eric LaMar, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2001
pp. 0223
Volume visualization of large data sets suffers from the same problem that many other visualization modalities suffer from: either one can visualize the entire data set and loose small details or visualize a small region and loose the context. In this pape...
 
Comparative Visual Analysis of Lagrangian Transport in CFD Ensembles
Found in: IEEE Transactions on Visualization and Computer Graphics
By Mathias Hummel,Harald Obermaier,Christoph Garth,Kenneth I. Joy
Issue Date:December 2013
pp. 2743-2752
Sets of simulation runs based on parameter and model variation, so-called ensembles, are increasingly used to model physical behaviors whose parameter space is too large or complex to be explored automatically. Visualization plays a key role in conveying i...
 
Characterizing and Visualizing Predictive Uncertainty in Numerical Ensembles Through Bayesian Model Averaging
Found in: IEEE Transactions on Visualization and Computer Graphics
By Luke Gosink,Kevin Bensema,Trenton Pulsipher,Harald Obermaier,Michael Henry,Hank Childs,Kenneth I. Joy
Issue Date:December 2013
pp. 2703-2712
Numerical ensemble forecasting is a powerful tool that drives many risk analysis efforts and decision making tasks. These ensembles are composed of individual simulations that each uniquely model a possible outcome for a common event of interest: e.g., the...
 
Visualization of Flow Behavior in Earth Mantle Convection
Found in: IEEE Transactions on Visualization and Computer Graphics
By Simon Schroder,John A. Peterson,Harald Obermaier,Louise H. Kellogg,Kenneth I. Joy,Hans Hagen
Issue Date:December 2012
pp. 2198-2207
A fundamental characteristic of fluid flow is that it causes mixing: introduce a dye into a flow, and it will disperse. Mixing can be used as a method to visualize and characterize flow. Because mixing is a process that occurs over time, it is a 4D problem...
 
Derived Metric Tensors for Flow Surface Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Harald Obermaier,Kenneth I. Joy
Issue Date:December 2012
pp. 2149-2158
Integral flow surfaces constitute a widely used flow visualization tool due to their capability to convey important flow information such as fluid transport, mixing, and domain segmentation. Current flow surface rendering techniques limit their expressiven...
 
IRIS: Illustrative Rendering for Integral Surfaces
Found in: IEEE Transactions on Visualization and Computer Graphics
By Mathias Hummel, Christoph Garth, Bernd Hamann, Hans Hagen, Kenneth I. Joy
Issue Date:November 2010
pp. 1319-1328
Integral surfaces are ideal tools to illustrate vector fields and fluid flow structures. However, these surfaces can be visually complex and exhibit difficult geometric properties, owing to strong stretching, shearing and folding of the flow from which the...
 
Query-Driven Visualization of Time-Varying Adaptive Mesh Refinement Data
Found in: IEEE Transactions on Visualization and Computer Graphics
By Luke J. Gosink, John C. Anderson, E. Wes Bethel, Kenneth I. Joy
Issue Date:November 2008
pp. 1715-1722
The visualization and analysis of AMR-based simulations is integral to the process of obtaining new insight in scientific research. We present a new method for performing query-driven visualization and analysis on AMR data, with specific emphasis on time-v...
 
Variable Interactions in Query-Driven Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Luke Gosink, John Anderson, Wes Bethel, Kenneth Joy
Issue Date:November 2007
pp. 1400-1407
Our ability to generate ever-larger, increasingly-complex data, has established the need for scalable methods that identify, and provide insight into, important variable trends and interactions. Query-driven methods are among the small subset of techniques...
 
Investigating Lossy Image Coding Using the PLHaar Transform
Found in: Data Compression Conference
By Joshua G. Senecal, Peter Lindstrom, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:March 2005
pp. 479-479
No summary available.
   
Physically Based Methods for Tensor Field Visualization
Found in: Visualization Conference, IEEE
By Ingrid Hotz, Louis Feng, Hans Hagen, Bernd Hamann, Kenneth Joy, Boris Jeremic
Issue Date:October 2004
pp. 123-130
<p>The physical interpretation of mathematical features of tensor fields is highly application-specific. Existing visualization methods for tensor fields only cover a fraction of the broad application areas. We present a visualization method tailored...
 
Interactive View-Dependent Rendering of Large IsoSurfaces
Found in: Visualization Conference, IEEE
By Benjamin Gregorski, Mark Duchaineau, Peter Lindstrom, Valerio Pascucci, Kenneth I. Joy
Issue Date:November 2002
pp. N/A
We present an algorithm for interactively extracting and rendering isosurfaces of large volume datasets in a view-dependent fashion. A recursive tetrahedral mesh refinement scheme, based on longest edge bisection, is used to hierarchically decompose the da...
 
Guest Editor's Introduction: Special issue on IEEE Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Kenneth I. Joy
Issue Date:July 2002
pp. 209-210
No summary available.
 
Real-Time Out-of-Core Visualization of Particle Traces
Found in: Parallel and Large-Data Visualization and Graphics, IEEE Symposium on
By Ralph Bruckschen, Falko Kuester, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2001
pp. 45-50
Visualization of particle traces provides intuitive and efficient means for the exploration and analysis of complex vector fields. This paper presents a method suitable for the real-time visualization of arbitrarily large time-varying vector fields in virt...
 
Fury of the Swarm: Efficient and Very Accurate Triangulation for Multi-view Scene Reconstruction
Found in: 2013 IEEE International Conference on Computer Vision Workshops (ICCVW)
By Shawn Recker,Mauricio Hess-Flores,Kenneth I. Joy
Issue Date:December 2013
pp. 652-659
This paper presents a novel framework for practical and accurate N-view triangulation of scene points. The algorithm is based on applying swarm optimization inside a robustly-computed bounding box, using an angular error-based L1 cost function which is mor...
 
Statistical angular error-based triangulation for efficient and accurate multi-view scene reconstruction
Found in: 2013 IEEE Workshop on Applications of Computer Vision (WACV)
By Shawn Recker,Mauricio Hess-Flores,Kenneth I. Joy
Issue Date:January 2013
pp. 68-75
This paper presents a framework for N-view triangulation of scene points, which improves processing time and final reprojection error with respect to standard methods, such as linear triangulation. The framework introduces an angular error-based cost funct...
 
Visualization of scene structure uncertainty in multi-view reconstruction
Found in: 2012 IEEE Applied Imagery Pattern Recognition Workshop (AIPR 2012)
By Shawn Recker,Mauricio Hess-Flores,Mark A. Duchaineau,Kenneth I. Joy
Issue Date:October 2012
pp. 1-7
This paper presents an interactive visualization system, based upon previous work, that allows for the analysis of scene structure uncertainty and its sensitivity to parameters in different multi-view scene reconstruction stages. Given a set of input camer...
 
Path-based constraints for accurate scene reconstruction from aerial video
Found in: 2012 IEEE Applied Imagery Pattern Recognition Workshop (AIPR 2012)
By Mauricio Hess-Flores,Mark A. Duchaineau,Kenneth I. Joy
Issue Date:October 2012
pp. 1-8
This paper discusses the constraints imposed by the path of a moving camera in multi-view sequential scene reconstruction scenarios such as in aerial video, which allow for an efficient detection and correction of inaccuracies in the feature tracking and s...
 
Visualization of material interface stability
Found in: Visualization Symposium, IEEE Pacific
By Harald Obermaier,Fang Chen,Hans Hagen,Kenneth I. Joy
Issue Date:March 2012
pp. 225-232
Material interfaces and free surfaces are a topic of increasing interest in the field of computational fluid dynamics. In parts, reconstructed interfaces from such multi-fluid simulations behave like classic integral surfaces as known in the visualization ...
 
Streamline Integration Using MPI-Hybrid Parallelism on a Large Multicore Architecture
Found in: IEEE Transactions on Visualization and Computer Graphics
By David Camp,Christoph Garth,Hank Childs,Dave Pugmire,Kenneth I. Joy
Issue Date:November 2011
pp. 1702-1713
Streamline computation in a very large vector field data set represents a significant challenge due to the nonlocal and data-dependent nature of streamline integration. In this paper, we conduct a study of the performance characteristics of hybrid parallel...
 
Fast, Memory-Efficient Cell Location in Unstructured Grids for Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Christoph Garth, Kenneth I. Joy
Issue Date:November 2010
pp. 1541-1550
Applying certain visualization techniques to datasets described on unstructured grids requires the interpolation of variables of interest at arbitrary locations within the dataset's domain of definition. Typical solutions to the problem of finding the grid...
 
An Application of Multivariate Statistical Analysis for Query-Driven Visualization
Found in: IEEE Transactions on Visualization and Computer Graphics
By Luke J. Gosink, Christoph Garth, John C. Anderson, E. Wes Bethel, Kenneth I. Joy
Issue Date:March 2011
pp. 264-275
Driven by the ability to generate ever-larger, increasingly complex data, there is an urgent need in the scientific community for scalable analysis methods that can rapidly identify salient trends in scientific data. Query-Driven Visualization (QDV) strate...
 
Smooth, Volume-Accurate Material Interface Reconstruction
Found in: IEEE Transactions on Visualization and Computer Graphics
By John C. Anderson, Christoph Garth, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:September 2010
pp. 802-814
A new material interface reconstruction method for volume fraction data is presented. Our method is comprised of two components: first, we generate initial interface topology; then, using a combination of smoothing and volumetric forces within an active in...
 
Time and Streak Surfaces for Flow Visualization in Large Time-Varying Data Sets
Found in: IEEE Transactions on Visualization and Computer Graphics
By Hari Krishnan, Christoph Garth, Kenneth Joy
Issue Date:November 2009
pp. 1267-1274
Time and streak surfaces are ideal tools to illustrate time-varying vector fields since they directly appeal to the intuition about coherently moving particles. However, efficient generation of high-quality time and streak surfaces for complex, large and t...
 
Generation of Accurate Integral Surfaces in Time-Dependent Vector Fields
Found in: IEEE Transactions on Visualization and Computer Graphics
By Christoph Garth, Han Krishnan, Xavier Tricoche, Tom Tricoche, Kenneth I. Joy
Issue Date:November 2008
pp. 1404-1411
We present a novel approach for the direct computation of integral surfaces in time-dependent vector fields. As opposed to previous work, which we analyze in detail, our approach is based on a separation of integral surface computation into two stages: sur...
 
Genus Oblivious Cross Parameterization: Robust Topological Management of Inter-Surface Maps
Found in: Computer Graphics and Applications, Pacific Conference on
By Janine Bennett, Valerio Pascucci, Kenneth Joy
Issue Date:November 2007
pp. 238-247
<p>We consider the problem of generating a map between two triangulated meshes, M and M?, with arbitrary and possibly differing genus. This problem has rarely been tackled in its generality. Early schemes considered only topological spheres. Recent a...
 
Anisotropic Noise Samples
Found in: IEEE Transactions on Visualization and Computer Graphics
By Louis Feng, Ingrid Hotz, Bernd Hamann, Kenneth Joy
Issue Date:March 2008
pp. 342-354
We present a practical approach to generate stochastic anisotropic samples with Poisson-disk characteristic over a two-dimensional domain. In contrast to isotropic samples, we understand anisotropic samples as non-overlapping ellipses whose size and densit...
 
Marching Diamonds for Unstructured Meshes
Found in: Visualization Conference, IEEE
By John C. Anderson, Janine C. Bennett, Kenneth I. Joy
Issue Date:October 2005
pp. 54
We present a higher-order approach to the extraction of isosurfaces from unstructured meshes. Existing methods use linear interpolation along each mesh edge to find isosurface intersections. In contrast, our method determines intersections by performing ba...
 
Real-Time Optimal Adaptation for Planetary Geometry and Texture: 4-8 Tile Hierarchies
Found in: IEEE Transactions on Visualization and Computer Graphics
By Lok M. Hwa, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:July 2005
pp. 355-368
The real-time display of huge geometry and imagery databases involves view-dependent approximations, typically through the use of precomputed hierarchies that are selectively refined at runtime. A classic motivating problem is terrain visualization in whic...
 
Adaptive Extraction of Time-Varying Isosurfaces
Found in: IEEE Transactions on Visualization and Computer Graphics
By Benjamin Gregorski, Joshua Senecal, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:November 2004
pp. 683-694
We present an algorithm for adaptively extracting and rendering isosurfaces from compressed time-varying volume data sets. Tetrahedral meshes defined by longest edge bisection are used to create a multiresolution representation of the volume in the spatial...
 
An Improved N-Bit to N-Bit Reversible Haar-Like Transform
Found in: Computer Graphics and Applications, Pacific Conference on
By Joshua G. Senecal, Peter Lindstrom, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:October 2004
pp. 371-380
We introduce the Piecewise-Linear Haar (PLHaar) transform, a reversible n-bit to n-bit transform that is based on the Haar wavelet transform. PLHaar is continuous, while all current n-bit to n-bit methods are not, and is therefore uniquely usable with both...
 
Multi-Dimensional Transfer Functions for Interactive 3D Flow Visualization
Found in: Computer Graphics and Applications, Pacific Conference on
By Sung W. Park, Brian Budge, Lars Linsen, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2004
pp. 177-185
Transfer functions are a standard technique used in volume rendering to assign color and opacity to a volume of a scalar field. Multi-dimensional transfer functions (MDTFs) have proven to be an effective way to extract specific features with subtle propert...
 
Adaptive 4-8 Texture Hierarchies
Found in: Visualization Conference, IEEE
By Lok M. Hwa, Mark A. Duchaineau, Kenneth I. Joy
Issue Date:October 2004
pp. 219-226
<p>We address the texture level-of-detail problem for extremely large surfaces such as terrain during realtime, view-dependent rendering. A novel texture hierarchy is introduced based on 4-8 refinement of raster tiles, in which the texture grids in e...
 
Generalized B-Spline Subdivision-Surface Wavelets for Geometry Compression
Found in: IEEE Transactions on Visualization and Computer Graphics
By Martin Bertram, Mark A. Duchaineau, Bernd Hamann, Kenneth I. Joy
Issue Date:May 2004
pp. 326-338
<p><b>Abstract</b>—We present a new construction of lifted biorthogonal wavelets on surfaces of arbitrary two-manifold topology for compression and multiresolution representation. Our method combines three approaches: subdivision surfaces...
 
Topological Segmentation in Three-Dimensional Vector Fields
Found in: IEEE Transactions on Visualization and Computer Graphics
By Karim Mahrous, Janine Bennett, Gerik Scheuermann, Bernd Hamann, Kenneth I. Joy
Issue Date:March 2004
pp. 198-205
<p><b>Abstract</b>—We present a new method for topological segmentation in steady three-dimensional vector fields. Depending on desired properties, the algorithm replaces the original vector field by a derived segmented data set, which is...
 
Reversible n-Bit to n-Bit Integer Haar-Like Transforms
Found in: Data Compression Conference
By Joshua Senecal, Mark Duchaineau, Kenneth I. Joy
Issue Date:March 2004
pp. 564
No summary available.
   
Length-Limited Variable-to-Variable Length Codes For High-Performance Entropy Coding
Found in: Data Compression Conference
By Joshua Senecal, Mark Duchaineau, Kenneth I. Joy
Issue Date:March 2004
pp. 389
Arithmetic coding achieves a superior coding rate when encoding a binary source, but its lack of speed makes it an inferior choice when true high-performance encoding is needed. We present our work on a practical implementation of fast entropy coders for b...
 
Material Interface Reconstruction
Found in: IEEE Transactions on Visualization and Computer Graphics
By Kathleen S. Bonnell, Mark A. Duchaineau, Daniel R. Schikore, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2003
pp. 500-511
<p><b>Abstract</b>—This paper presents an algorithm for material interface reconstruction for data sets where fractional material information is given as a percentage for each element of the underlying grid. The reconstruction problem is ...
 
Hierarchical Clustering for Unstructured Volumetric Scalar Fields
Found in: Visualization Conference, IEEE
By Christopher S. Co, Bjoern Heckel, Hans Hagen, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2003
pp. 43
We present a method to represent unstructured scalar fields at multiple levels of detail. Using a parallelizable classification algorithm to build a cluster hierarchy, we generate a multiresolution representation of a given volumetric scalar data set. The ...
 
Iso-Splatting: A Point-Based Alternative to Isosurface Visualization
Found in: Computer Graphics and Applications, Pacific Conference on
By Christopher S. Co, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2003
pp. 325
We present a new approach to isosurface visualization that we call
 
Deploying Web-Based Visual Exploration Tools on the Grid
Found in: IEEE Computer Graphics and Applications
By T.J. Jankun-Kelly, Oliver Kreylos, Kwan-Liu Ma, Bernd Hamann, Kenneth I. Joy, John Shalf, E. Wes Bethel
Issue Date:March 2003
pp. 40-50
<p>A Web-based portal enables the exploration, encapsulation, and dissemination of visualization results over the grid. This portal integrates an interface client for structured visualization exploration, a visualization Web application to manage the...
 
Hierarchical Representation of Time-Varying Volume Data with
Found in: Computer Graphics and Applications, Pacific Conference on
By Lars Linsen, Valerio Pascucci, Mark A. Duchaineau, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2002
pp. 346
<p>Multiresolution methods for representing data at multiple levels of detail are widely used for large-scale two- and three-dimensional data sets. We present a four-dimensional multiresolution approach for time-varying volume data. This approach sup...
 
Wavelet Representation of Contour Sets
Found in: Visualization Conference, IEEE
By Martin Bertram, Daniel E. Laney, Mark A. Duchaineau, Charles D. Hansen, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2001
pp. N/A
We present a new wavelet compression and multiresolution modeling approach for sets of contours (level sets). In contrast to previous wavelet schemes, our algorithm creates parametrization of a scalar field induced by its contours and compactly stores this...
 
Interactive Display of Surfaces Using Subdivision Surfaces and Wavelets
Found in: Computer Graphics, Spring Conference on
By Mark A. Duchaineau, Martin Bertram, Serban Porumbescu, Bernd Hamann, Kenneth I. Joy
Issue Date:April 2001
pp. 0118
Abstract: Complex surfaces and solids are produced by large-scale modeling and simulation activities in a variety of disciplines. Productive interaction with these simulations requires that these surfaces or solids be viewable at interactive rates - yet ma...
 
Bicubic Subdivision-Surface Wavelets for Large-Scale Isosurface Representation and Visualization
Found in: Visualization Conference, IEEE
By Martin Bertram, Mark A. Duchaineau, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2000
pp. 69
We introduce a new subdivision-surface wavelet transform for arbitrary two-manifolds with boundary that is the first to use simple lifting-style filtering operations with bicubic precision. We also describe a conversion process for re-mapping large-scale i...
 
Constructing Material Interfaces From Data Sets with Volume-Fraction Information
Found in: Visualization Conference, IEEE
By Kathleen S. Bonnell, Mark A. Duchaineau, Daniel R. Schikore, Bernd Hamann, Kenneth I. Joy
Issue Date:October 2000
pp. 66
We present a new algorithm for material boundary interface reconstruction from data sets containing volume fractions. We transform the reconstruction problem to a problem that analyzes the dual data set, where each vertex in the dual mesh has an associated...
 
Using Isosurface Methods for Visualizing the Envelope of a Swept Trivariate Solid
Found in: Computer Graphics and Applications, Pacific Conference on
By Jason Conkey, Kenneth I. Joy
Issue Date:October 2000
pp. 272
We present a method for calculating the envelope surface of a parametric solid object swept along a path in three-dimensional space. The boundary surface of the solid is the combination of parametric surfaces and an implicit surface where the Jacobian of t...
 
Reconstruction of B-Spline Surfaces from Scattered Data Points
Found in: Computer Graphics International Conference
By Benjamin Gregorski, Bernd Hamann at Kenneth I. Joy
Issue Date:June 2000
pp. 163
We present a new approach for reconstructing a smooth surface from a set of scattered points in three-dimensional (3D) space. Our algorithm first decomposes a given point set into a quadtree-like data structure known as a strip tree. The strip tree is used...
 
Construction of Vector Field Hierarchies
Found in: Visualization Conference, IEEE
By Bjoern Heckel, Gunther Weber, Bernd Hamann, Kenneth I. Joy
Issue Date:October 1999
pp. 1
We present a method for the hierarchical representation of vector fields. Our approach is based on iterative refinement using clustering and principal component analysis. The input to our algorithm is a discrete set of points with associated vectors. The a...
 
Multiresolution Techniques for Interactive Texture-based Volume Visualization
Found in: Visualization Conference, IEEE
By Eric C La Mar, Bernd Hamann, Kenneth I. Joy
Issue Date:October 1999
pp. 60
We present a multiresolution technique for interactive texture-based volume visualization of very large data sets. This method uses an adaptive scheme that renders the volume in a region-of-interest at a high resolution and the volume away from this region...
 
Boundary Determination for Trivariate Solids
Found in: Computer Graphics and Applications, Pacific Conference on
By Kenneth I. Joy, Mark A. Duchaineau
Issue Date:October 1999
pp. 82
The trivariate tensor-product B-spline solid is a direct extension of the B-spline patch and has been shown to be useful in the creation and visualization of free-form geometric solids. Visualizing these solid objects requires the determination of the boun...
 
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