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CreatorTitleDescriptionSubjectDate
51 Thompson, William B.; Willemsen, Peter; Gooch, Amy A.; Creem-Regehr, Sarah HopeDoes the quality of the computer graphics matter when judging distances in visually immersive environments?In the real world, people are quite accurate judging distances to locations in the environment, at least for targets resting on the ground plane and distances out to about 20m. Distance judgments in visually immersive environments are much less accurate. Several studies have now shown that in vis...Visually immersive environments2002-12-05
52 Hansen, Charles D.Flow charts: visualization of vector fields on arbitrary surfacesWe introduce a novel flow visualization method called Flow Charts, which uses a texture atlas approach for the visualization of flows defined over curved surfaces. In this scheme, the surface and its associated flow are segmented into overlapping patches, which are then parameterized and packed in ...2008-09
53 Lefohn, Aaron; Whitaker, Ross T.A GPU-based, three-dimensional level set solver with curvature flowLevel set methods are a powerful tool for implicitly representing deformable surfaces. Since their inception, these techniques have been used to solve prob- lems in fields as varied as computer vision, scientific visualization, computer graphics and computational physics. With the power and flexi...GPU-based; Level set solver2002-12-11
54 Willemsen, Peter; Gooch, Amy A.An experimental comparison of perceived egocentric distance in real, image-based, and traditional virtual environment using direct walking tasksIn virtual environments, perceived egocentric distances are often underestimated when compared to the same distance judgments in the real world. The research presented in this paper explores two possible causes for this reduced distance perception in virtual environments: (1) real-time computer g...Egocentric distances; Virtual environments2002-02-12
55 Parker, Steven G.Massively parallel software rendering for visualizing large-scale data setsFor 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 t...Parallel rendering; Volume rendering; Ray tracing; Isosurfacing2001
56 Shirley, Peter S.Natural image statistics for computer graphicsThe class of all natural images is an infinitely small fraction of all possible images. The structure of natural images can be statistically modeled, revealing striking regularities. The human visual system appears to be optimized to view natural images, as opposed to any possible image, and therefo...Natural image2001
57 Kirby, Robert MichaelVerifying volume rendering using discretization error analysisWe propose an approach for verification of volume rendering correctness based on an analysis of the volume rendering integral, the basis of most DVR algorithms. With respect to the most common discretization of this continuous model (Riemann summation), we make assumptions about the impact of parame...2014-01-01
58 Reinhard, Erik; Stark, Michael M.; Shirley, Peter S.Photographic tone reproduction for digital imagesA classic photographic task is the mapping of the potentially high dynamic range of real world luminances to the low dynamic range of the photographic print. This tone reproduction problem is also faced by computer graphics practitioners who must map digital images to a low dynamic range print or...Tone reproduction operator; Photographic tone2002-01-14
59 Lefohn, Aaron; Cates, Joshua E.; Whitaker, Ross T.Interactive, GPU-based level sets for 3D brain tumor segmentationWhile level sets have demonstrated a great potential for 3D medical image seg- mentation, their usefulness has been limited by two problems. First, 3D level sets are relatively slow to compute. Second, their formulation usually entails several free parameters which can be very difficult to correc...Level sets; Medical imaging; 3D brain tumor segmentation2003-04-16
60 Bargteil, Adam WadeStrain limiting for clustered shape matchingIn this paper, we advocate explicit symplectic Euler integration and strain limiting in a shape matching simulation framework. The resulting approach resembles not only previous work on shape matching and strain limiting, but also the recently popular position-based dynamics. However, unlike this pr...2014-01-01
61 Hansen, Charles D.Fast data parallel polygon renderingThis paper describes a data parallel method for polygon rendering on a massively parallel machine. This method, based on a simple shading model, is targeted for applications which require very fast rendering for extremely large sets of polygons. Such sets are found in many scienti c visualization ap...1993
62 Stark, Michael M.; Martin, William; Cohen, Elaine; Lyche, Tom; Riesenfeld, Richard F.B-splines for physically-based renderingAlthough B-spline curves and surfaces have enjoyed a long established place in the graphics community as constructive modeling tools, the use of B-spline approximation techniques has received relatively little attention in rendering. In this work we explore the use of 4D and 5D tensor product B-s...B-spline curves; Rendering algorithms2002-01-09
63 Wyman, Chris; Hansen, Charles D.Penumbra mapsGenerating soft shadows quickly is difficult. Few techniques have enough flexibility to interactively render soft shadows in scenes with arbitrarily complex occluders and receivers. This paper introduces the penumbra map, which extends current shadow map techniques to interactively approximate so...Penumbra maps; Soft shadows; Shadow maps2003-04-23
64 Wyman, Chris; Hansen, Charles D.; Shirley, Peter S.Interactive raytraced causticsIn computer graphics, bright patterns of light focused onto matte surfaces are called ?caustics?. We present a method for rendering dynamic scenes with moving caustics at interactive rates. This technique requires some simplifying assumptions about caustic behavior allowing us to consider it a lo...Raytraced caustics2003-04-23
65 Riesenfeld, Richard F.Computer aided designThe report is based on the proposal submitted to the National Science Foundation in September 1981, as part of the Coordinated Experimental Computer Science Research Program. The sections covering the budget and biographical data on the senior research personnel have not been included. Also, the sec...1984
66 Evans, DavidGraphical man/machine communications: May 1967Semiannual technical report for period ending 15 May, 1967.1967-05
67 Pascucci, ValerioFlow visualization with quantified spatial and temporal errors using edge mapsRobust analysis of vector fields has been established as an important tool for deriving insights from the complex systems these fields model. Traditional analysis and visualization techniques rely primarily on computing streamlines through numerical integration. The inherent numerical errors of such...2012-01-01
68 Brunvand, Erik L.Estimating performance of an ray- tracing ASIC designRecursive ray tracing is a powerful rendering technique used to compute realistic images by simulating the global light transport in a scene. Algorithmic improvements and FPGA-based hardware implementations of ray tracing have demonstrated realtime performance but hardware that achieves performance ...2006
69 Parker, Steven G.Practical global illumination for interactive particle visualizationParticle-based simulation methods are used to model a wide range of complex phenomena and to solve time-dependent problems of various scales. Effective visualizations of the resulting state will communicate subtle changes in the three-dimensional structure, spatial organization, and qualitative tren...Interactive particle visualization; Global illumination; Ray tracing; Luminance textures2008-02
70 Gooch, Bruce; Reinhard, Erik; Moulding, Chris; Shirley, Peter S.Artistic composition for image creationAltering the viewing parameters of a 3D object results in computer graphics images of varying quality. One aspect of image quality is the composition of the image. While the esthetic properties of an image are subjective, some heuristics used by artists to create images can be approximated quanti...Image creation; Image quality2000
71 Parker, Steven G.; Hansen, Charles D.Distributed interactive ray tracing for large volume visualizationWe have constructed a distributed parallel ray tracing system that interactively produces isosurface renderings from large data sets on a cluster of commodity PCs. The program was derived from the SCI Institute's interactive ray tracer (*-Ray), which utilizes small to large shared memory platforms, ...Ray tracing; Volume rendering; Large data; Cluster computing; Distributed shared memory2003
72 Hansen, Charles D.; Wald, IngoInteractive isosurface ray tracing of time-varying tetrahedral volumesAbstract- We describe a system for interactively rendering isosurfaces of tetrahedral finite-element scalar fields using coherent ray tracing techniques on the CPU. By employing state-of-the art methods in polygonal ray tracing, namely aggressive packet/frustum traversal of a bounding volume hierarc...2007-11
73 Hansen, Charles D.Volume Ray casting with peak finding and differential samplingDirect volume rendering and isosurfacing are ubiquitous rendering techniques in scientific visualization, commonly employed in imaging 3D data from simulation and scan sources. Conventionally, these methods have been treated as separate modalities, necessitating different sampling strategies and ren...2009-11
74 Hansen, Charles D.; Chien, Chi-BinInteractive visualization tool for multi-channel confocal microscopy data in neurobiology researchConfocal microscopy is widely used in neurobiology for studying the three-dimensional structure of the nervous system. Confocal image data are often multi-channel, with each channel resulting from a different fluorescent dye or fluorescent protein; one channel may have dense data, while another has ...Volume rendering; Zebrafish2009-11
75 Kniss, Joe; Ikits, Milan; Lefohn, Aaron; Hansen, Charles D.Closed-form approximations to the volume rendering integral with Gaussian transfer functionsIn direct volume rendering, transfer functions map data points to optical properties such as color and opacity. We have found transfer functions based on the Gaussian primitive to be particularly useful for multivariate volumes, because they are simple and rely on a limited number of free paramet...Volume rendering2003-07-25
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