Publications
Next Generation Visual Supercomputing Using PC Clusters With Volume Graphics Hardware Devices
Shigeru Muraki, Masato Ogata, Kwan-Liu Ma, Kenji Koshizuka, Kagenori Kajihara, Xuezhen Liu, Yasutada Nagano, and Kazuro ShimokawaIn Proceedings of Supercomputing 2001
November, 2001, pp. 44-52To seek a low-cost, extensible solution for the large-scale data visualization problem, a visual computing system is designed as a result of a collaboration between industry and government research laboratories in Japan, also with participation by researchers in U.S. This scalable system is a commodity PC cluster equipped with the VolumePro 500 volume graphics cards and a specially designed image compositing hardware ...
High-Quality Volume Rendering of Adaptive Mesh Refinement Data
Gunther H. Weber, Oliver Kreylos, Terry J. Ligocki, John M. Shalf, Hans Hagen, Bernd Hamann, Kenneth I. Joy, and Kwan-Liu MaIn Proceedings of Vision, Modeling, and Visualization
November, 2001, pp. 121-128Adaptive mesh refinement (AMR) is a numerical simulation technique used in computational fluid dynamics (CFD). By using a set of nested grids of different resolutions, AMR combines the simplicity of structured rectilinear grids with the ability to adapt to local changes in complexity in the domain. Without proper interpolation on the boundaries of grids of different levels of a hierarchy, discontinuities can arise. ...
Non-Photorealistic Rendering Using Watercolor Inspired Textures and Illumination
Eric Lum and Kwan-Liu MaIn Proceedings of Pacific Graphics 2001
October, 2001, pp. 322-330In this paper, we present a watercolor inspired method for the rendering of surfaces. Our approach mimics the watercolor process by building up an illuminated scene through the compositing of several layers of semitransparent paint. The key steps consist of creating textures for each layer using LIC of Perlin Noise, and then calculating the layer thickness distribution using an inverted subtractive lighting model ...
Multiresolution View-Dependent Splat Based Volume Rendering of Large Irregular Data
Jeremy Meredith and Kwan-Liu MaIn Proceedings of Parallel and Large-Data Visualization and Graphics Symposium
October, 2001, pp. 93-99We present techniques for multiresolution approximation and hardware-assisted splat based rendering to achieve interactive volume visualization of large irregular data sets. We examine two methods of generating multiple resolutions of irregular volumetric grids and a data structure supporting the splatting approach for volume rendering. These techniques are implemented in combination with a view-dependent error based resolution selection to maintain accuracy at both low and high zoom levels. ...
Texture Hardware Assisted Rendering of Time-Varying Volume Data
Eric Lum, Kwan-Liu Ma, and John ClyneIn Proceedings of IEEE Visualization 2001 Conference
October, 2001, pp. 263-270In this paper we present a hardware-assisted rendering technique coupled with a compression scheme for the interactive visual exploration of time-varying scalar volume data. A palette-based decoding technique and an adaptive bit allocation scheme are developed to fully utilize the texturing capability of a commodity 3-D graphics card. Using a single PC equipped with a modest amount of memory, a texture capable graphics card, and an inexpensive disk array, we are able to render hundreds of time steps of regularly gridded volume data (up to 45 millions voxels each time step) at interactive rates, permitting the visual exploration of large scientific data sets in both the temporal and spatial domain ...
Strategies for Visualizing Time-Varying Volume Data
Kwan-Liu Ma and Eric LumIn Proceedings of Seventh International Conference on Computer Aided Design and Computer Graphics
August, 2001, pp. 291-297Our ability to study and understand complex, transient phenomena is critical to solving many scientific and engineering problems. This paper addresses the issues in storage space, I/O, and rendering for visualizing time-varying volume data. A suite of effective techniques, including encoding, parallel rendering, and runtime visualization techniques are discussed. In particular, we introduce a new hardware-assisted technique coupled with a compression scheme based on Discrete Cosine Transform which allows interactive exploration in both spatial and temporal domains of the data using a PC with a commodity graphics card ...
Visualization Exploration and Encapsulation Via a Spreadsheet-Like Interface
T.J. Jankun-Kelly and Kwan-Liu MaIEEE Transactions on Visualization and Computer Graphics
Volume 7, Number 3, July-September, 2001, pp. 275-287Exploring complex, very large data sets requires interfaces to present and navigate through the visualization of the data. Two types of audience benefit from such coherent organization and representation: first, the user of the visualization system can examine and evaluate their data more efficiently; second, collaborators or reviewers can quickly understand and extend the visualization. The needs of these two groups are addressed by the spreadsheet-like interface described here ...
Large-Scale Data Visualization
Kwan-Liu MaIEEE Computer Graphics and Applications
Volume 21, Number 4, July, 2001, pp. 22-23Scientists nowadays have unprecedented computing and instrumental capability for studying natural phenomena at greater accuracy, resulting in an explosive growth of data. For example, the data generated by modeling next-generation accelerators can have from hundreds of millions to billions of particle paths. For Earth sciences turbulence calculations, each run can produce thousands of time steps ...
Massively Parallel Software Rendering for Visualizing Large-Scale Data Sets
Kwan-Liu Ma and Steven ParkerIEEE Computer Graphics and Applications
Volume 21, Number 4, July, 2001, pp. 72-83For some time, researchers have done production visualization almost exclusively using high-end graphics workstations. They routinely archived and analyzed the outputs of simulations running on massively parallel supercomputers. Generally, a feature extraction step and a geometric modeling step to significantly reduce the data's size preceded the actual data rendering. Researchers also used this procedure to visualize ...
VG Cluster: A Scalable Visual Computing System
Shigeru Muraki, Masato Ogata, Kenji Koshizuka, Kagenori Kajihara, Xuezhen Liu, Yasutada Nagano, Kazuro Shimokawa, and Kwan-Liu MaIn Proceedings of Visual Computing
June, 2001, pp. 85-90...
Layer Data Organization for Visualizing Unstructured-Grid Data
Kwan-Liu Ma, Gheni Abla, and Eric LumIn Proceedings of Visual Data Exploration and Analysis VIII
January, 2001, pp. 111-120Unstructured grid discretizations have become increasingly popular for computational modeling of engineering problems involving complex geometries. However, the use of 3-d unstructured grids complicates the visualization task, since the resulting data sets are irregular both geometrically and topologically. The need to store and access additional information about the structure of the grid can lead to visualization algorithms which incur considerable memory and computational overhead ...
Visualization of Adaptive Mesh Refinement Data
Gunther H. Weber, Hans Hagen, Bernd Hamann, Kenneth I. Joy, Terry J. Ligocki, Kwan-Liu Ma, and John M. ShalfIn Proceedings of Visual Data Exploration and Analysis VIII
SPIE, Vol. 4302, January, 2001, pp. 121-132The complexity of physical phenomena often varies substantially over space and time. There can be regions where a physical phenomenon/quantity varies very little over a large extent. At the same time, there can be small regions where the same quantity exhibits highly complex variations. Adaptive mesh refinement (AMR) is a technique used in computational fluid dynamics (CFD) to simulate phenomena with drastically varying scales concerning the complexity of the simulated variables ...
A Study of Transfer Function Generation for Time-Varying Volume Data
T.J. Jankun-Kelly and Kwan-Liu MaIn Proceedings of Volume Graphics 2001
2001The proper usage and creation of transfer functions for time-varying data sets is an often ignored problem in volume visualization. Although methods and guidelines exist for time-invariant data, little formal study for the timevarying case has been performed. This paper examines this problem, and reports the study that we have conducted to determine how the dynamic behavior of time-varying data may be captured by a single or small set of transfer functions ...
A Parallel Volume-Rendering System Using Multiple-Shear Composition
Masato Ogata, Kagenori Kajihara, Shigeru Muraki, Kazuro Shimokawa, Yasunori Dohi, and Kwan-Liu MaJournal of the Institute of Image Information and Television Engineers
Volume 55, Number 7, July, 2001, pp. 1011-1018
Fast direct volume-rendering systems are in high demand due to the increasing amount of scientific data generated by a variety of computer simulations, of medical data obtained by MRI and CT scanners, and of geological, oceanographic, and meteorological data collected from various sensors. A notable characteristic shared by these data volumes is the sheer amount of data to be rendered. A huge amount of computing power is thus needed for animated visualization, which is essential to observe many physical phenomena ...
Towards the Massively Parallel Simulation and Visualization of Human Neuron System
Shigeru Muraki, Kazuro Shimokawa, Masato Ogata, Kagenori Kajihara, and Kwan-Liu MaIn Bit
Volume 33, Number 3, 2001, pp. 58-65
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