Issue No. 02 - April-June (2003 vol. 9)
Robert J. Moorhead , IEEE
This issue contains extended versions of six seminal papers taken from the IEEE Visualization 2002 Conference, the IEEE Symposium on Information Visualization, and the IEEE Volume Visualization and Graphics Symposium held in Boston in late October 2002. The six papers that are published herein were selected by a much more thorough and extensive selection and review process than in previous years. In particular, the IEEE Visualization Conference Steering Committee created a panel of experts to select the Best Visualization Conference Paper. That panel consisted of two of the three Visualization Conference Paper Cochairs, one director of the IEEE Computer Society Technical Committee on Visualization and Graphics (TCVG), and two at-large members of the TCVG. The specific members of the panel were: Markus Gross (chair), Robert Moorhead, Arie Kaufman, Amitabh Varshney, and Eduard Groeller. This committee selected eight papers to be considered for Best Paper, ultimately selecting a paper entitled "Non-Photorealistic Volume Rendering Using Stippling Techniques" by Aidong Lu, Christopher J. Morris, David Ebert, Penny Rheingans, and Charles Hansen. Although one of the authors, Dr. David Ebert, is the new EIC of the IEEE Transactions on Visualization and Computer Graphics, the authors of this paper were invited to extend that manuscript and the manuscript was scrupulously reviewed before Dr. Ebert became EIC. The other seven finalists were also invited to submit an extended version of their conference paper for this special section. The authors of each of the Best Papers selected by the organizers of the two associated symposia were likewise invited to submit an extended version of their symposia papers for this special section. Each revised paper was reviewed by several experts before they were recommended for acceptance. In two cases, extensive further revisions were dictated and the papers were only accepted after these revisions were made. The papers published herein represent a broad selection from the various research areas within the field of visualization.
The paper by Eric B. Lum, Aleksander Stompel, and Kwan-Liu Ma presents a novel technique for visualizing surface shape, namely kinetic visualization. Kinetic visualization uses particles in motion along the surface to show the shape and structure of 3D static objects. The authors compare kinetic visualization with the popular oriented textures techniques, pointing out that their new technique is fundamentally different. They note that kinetic visualization does not suffer from the limitations of the oriented textures approach in which the oriented textures used to show shape prohibit the rendering of real surface textures that might be used to illustrate the material properties of the surface. Furthermore, the authors note that textures have an inherent scale and do not respond well to magnification, thus limiting ones ability to zoom in to an object to see more details. A user study supports some of their conclusions. The reader is encouraged to examine the animations available via the TVCG website to appreciate the results.
The paper by Aidong Lu, Christopher J. Morris, Joe Taylor, David S. Ebert, Charles Hansen, Penny Rheingans, and Mart Hartner, extended from the IEEE Visualization 2002 Conference Best Paper, presents a highly parameterized framework to quickly render data volumes for preview using stippling techniques. The intent is to quickly render essential elements, such as silhouettes, surfaces, and the interior so that content can be quickly determined or the optimum orientation for further processing can be ascertained. The result is an approach that merges artistic principles with selectable and adjustable feature enhancement algorithms to create an interactive scientific visualization technique. The framework automatically generates resolution-appropriate point lists for both surface and volume models. Many example results of various combinations of feature enhancements are given.
The paper by Caixia Zhang and Roger Crawfis describes an algorithm to create soft shadows using a splatting technique. The algorithm builds on a basic shadow algorithm based on non-image-aligned sheet-based splatting. The algorithm is contrasted with an earlier hardware-based shadow creation algorithm by Kniss et al. [ 2], which is also based on a half-angle slicing technique. The paper describes the convolution techniques that are used and the implementation details. Several challenging scenes are rendered and the nuisances of the approach explained.
The well-written paper by Joe Kniss, Simon Premoze, Charles Hansen, Peter Shirley, and Allen McPherson presents an empirical model to approximate the effects of complex light transport. It presents a new, more complex, yet computationally feasible, lighting model that enables images to better represent scattering and shadows from translucent materials, such as clouds, where scattering dominates. The manuscript also describes two variations of volume perturbation methods that modify the data of the model to provide the rich visual effects of a high resolution model from a substantially smaller data set. The techniques improve both the speed and quality of volume visualizations. Recent graphics hardware using these models can produce volumetric renderings with subtle shading effects at interactive rates. Impressive example renderings are shown to substantiate the techniques.
The paper by Manfred Weiler, Martin Kraus, Markus Merz, and Thomas Ertl starts with a survey that could be entitled "the road from polygon to tetrahedron projection in hardware" and goes on to present two implementations of a view-independent cell projection algorithm for programmable graphics hardware. Both implementations compute the projection and scan conversion of the set of tetrahedral on the graphics hardware, making them synergistic with many of the hardware-accelerated optimizations for polygonal graphics, such as vertex arrays and display lists. Possible improvements for potential future graphics hardware are discussed, as well as applications for interactive volume visualization of unstructured meshes.
The paper by Chris Stolte, Diane Tang, and Pat Hanrahen addresses multiscale visualization techniques. Most people start with a broad overview of a problem and move in-and-out to discover and explore details. However, taking a large data set and abstracting the information into a coherent and meaningful hierarchical structure is a daunting task. This paper addresses the problem by addressing the need to organize and annotate the visual and data structures possible for interactive visualizations with different data types, providing a step toward greater compatibility between data mining and information visualization technologies.
Robert J. Moorhead II
The author is with the Engineering Research Center, Mississippi State University, PO Box 9627, Mississippi State, MS 39762.
Robert J. Moorhead II received the PhD degree in electrical and computer engineering and the MSEE degree from North Carolina State University in 1985 and 1982, respectively. He received the BSEE degree summa cum laude and with research honors from Geneva College in 1980. He is the Director of the Visualization, Analysis, and Imaging Lab in the GeoResources Institute and a professor of electrical and computer engineering at Mississippi State University. He previously worked as a research staff member in the Imaging Technologies Department at the IBM T.J. Watson Research Center from 1985 to 1988. He has authored more than 90 papers or book chapters on visualization, image processing, and computer communications. He has received funding from ARPA, ONR, NRL, AFOSR, the Army Waterways Experiment Station (now ERDC), the Naval Oceanographic Office, NASA, Raytheon, CSC, and Logicon. He was the lead conference cochair for the IEEE Visualization '97 Conference, the chair of the IEEE Computer Society's Technical Committee on Visualization and Graphics in 1999 and 2000, and the lead papers cochair for the IEEE Visualization 2002 Conference. He is a senior member of the IEEE.