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Display of Surfaces from Volume Data
, 1988
"... The application of volume rendering techniques to the display of surfaces from sampled scalar functions of three spatial dimensions is explored. Fitting of geometric primitives to the sampled data is not required. Images are formed by directly shading each sample and projecting it onto the picture p ..."
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Cited by 724 (10 self)
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The application of volume rendering techniques to the display of surfaces from sampled scalar functions of three spatial dimensions is explored. Fitting of geometric primitives to the sampled data is not required. Images are formed by directly shading each sample and projecting it onto the picture plane. Surface shading calculations are performed at every voxel with local gradient vectors serving as surface normals. In a separate step, surface classification operators are applied to obtain a partial opacity for every voxel. Operators that detect isovalue contour surfaces and region boundary surfaces are presented. Independence of shading and classification calculations insures an undistorted visualization of 3D shape. Nonbinary classification operators insure that small or poorly defined features are not lost. The resulting colors and opacities are composited from back to front along viewing rays to form an image. The technique is simple and fast, yet displays surfaces exhibiting smooth silhouettes and few other aliasing artifacts. The use of selective blurring and supersampling to further improve image quality is also described. Examples from two applications are given: molecular graphics and medical imaging.
Volume Rendering
, 1988
"... A technique for rendering images Of volumes containing mixtures of materials is presented. The shading model allows both the interior of a material and the boundary between materials to be colored. Image projection is performed by simulating the absorption of light along the ray path to the eye. The ..."
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Cited by 379 (2 self)
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A technique for rendering images Of volumes containing mixtures of materials is presented. The shading model allows both the interior of a material and the boundary between materials to be colored. Image projection is performed by simulating the absorption of light along the ray path to the eye. The algorithms used are designed to avoid artifacts caused by aliasing and quantization and can be efficiently implemented on an image computer. Images from a variety of applications are shown.
Efficient ray tracing of volume data
 ACM Transactions on Graphics
, 1990
"... Volume rendering is a technique for visualizing sampled scalar or vector fields of three spatial dimensions without fitting geometric primitives to the data. A subset of these techniques generates images by computing 2D projections of a colored semitransparent volume, where the color and opacity at ..."
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Cited by 325 (4 self)
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Volume rendering is a technique for visualizing sampled scalar or vector fields of three spatial dimensions without fitting geometric primitives to the data. A subset of these techniques generates images by computing 2D projections of a colored semitransparent volume, where the color and opacity at each point are derived from the data using local operators. Since all voxels participate in the generation of each image, rendering time grows linearly with the size of the dataset. This paper presents a fronttoback imageorder volumerendering algorithm and discusses two techniques for improving its performance. The first technique employs a pyramid of binary volumes to encode spatial coherence present in the data, and the second technique uses an opacity threshold to adaptively terminate ray tracing. Although the actual time saved depends on the data, speedups of an order of magnitude have been observed for datasets of useful size and complexity. Examples from two applications are given: medical imaging and molecular graphics.
TemplateBased Volume Viewing
, 1992
"... We present an efficient threephase algorithm for volume viewing that is based on exploit  t ing coherency between rays in parallel projection. The algorithm starts by building a ray emplate and determining a special plane for projection  the baseplane. Parallel rays are cast t into the volume ..."
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Cited by 61 (17 self)
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We present an efficient threephase algorithm for volume viewing that is based on exploit  t ing coherency between rays in parallel projection. The algorithm starts by building a ray emplate and determining a special plane for projection  the baseplane. Parallel rays are cast t into the volume from within the projected region of the volume on the baseplane, by repeating he sequence of steps specified in the raytemplate. We carefully choose the type of line to be s employed and the way the template is being placed on the baseplane in order to assure uniform ampling of the volume by the discrete rays. We conclude by describing an optimized software K implementation of our algorithm and reporting its performance. eywords: volume rendering, ray casting, template, parallel projection 1. Introduction Volume visualization is the process of converting complex volume data to a format that is p amenable to human understanding while maintaining the integrity and accuracy of the data. Th...
Applying Space Subdivision Techniques to Volume Rendering
 IEEE Visualization
, 1990
"... We present a new raytracing algorithm for volume rendering which is designed to work efficiently when the data of interest is distributed sparsely through the volume. A simple preprocessing step identifies the voxels representing features of interest. Frequently this set of voxels, arbitrarily dist ..."
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Cited by 28 (2 self)
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We present a new raytracing algorithm for volume rendering which is designed to work efficiently when the data of interest is distributed sparsely through the volume. A simple preprocessing step identifies the voxels representing features of interest. Frequently this set of voxels, arbitrarily distributed in three dimensional space, is a small fraction of the original voxel grid. A mediancut space partitioning scheme, combined with bounding volumes to prune void spaces in the resulting search structure, is used to store the voxels of interest in a kd tree. The tree is then efficiently raytraced to render the voxel data. The kd tree is view independent and can be used for animation sequences involving changes in positions of the viewer or positions of lights. We have applied this search structure to render voxel data from MRI, CAT Scan and electron density distributions. 1 Introduction An increasingly important application of computer graphics technology is in providing visualiza...
A Search Structure based on Kd Trees for Efficient Ray Tracing
, 1992
"... We present an experimental study of some of the important properties of space subdivision structures used to accelerate ray tracing. Location and orientation of partitioning planes, use of bounding volumes, methods to isolate void spaces in hierarchies and choice of traversal methods are examined to ..."
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Cited by 11 (0 self)
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We present an experimental study of some of the important properties of space subdivision structures used to accelerate ray tracing. Location and orientation of partitioning planes, use of bounding volumes, methods to isolate void spaces in hierarchies and choice of traversal methods are examined to determine their effect on performance. This has resulted in the development of a new search structure based on kd trees, which outperform acceleration schemes that exploit only a subset of the above characteristics. In addition to superior performance and greater adaptivity to scene characteristics, the flexibility of this structure allows it to terminate itself at the correct point, unlike the ad hoc schemes used by existing methods. This structure has been applied successfully to volume visualization applications, resulting in significant performance advantages. 1 Introduction A great deal of research has focused on discovering efficient ways to perform ray tracing, a sophisticated rend...
Towards Real Time Volume Rendering
, 1996
"... The task of real time rendering of today's volumetric datasets is still being tackled by several research groups. A quick calculation of the amount of computation required for realtime rendering of a high resolution volume puts us in the teraflop range. Yet, the demand to support such rendering cap ..."
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Cited by 6 (0 self)
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The task of real time rendering of today's volumetric datasets is still being tackled by several research groups. A quick calculation of the amount of computation required for realtime rendering of a high resolution volume puts us in the teraflop range. Yet, the demand to support such rendering capabilities is increasing due to emerging technologies such as virtual surgery simulation and rapid prototyping. There are five main approaches to overcoming this seemingly insurmountable performance barrier: (i) data reduction by means of model extraction or data simplification, (ii) realization of specialpurpose volume rendering engines, (iii) softwarebased algorithm optimization and acceleration, (iv) implementation on general purpose parallel architectures, and (v) use of contemporary oftheshelf graphics hardware. In this presentation we first describe the vision of realtime highresolution volume rendering and estimate the computing power it demands. We survey the stateofthe art in...
Efficient Techniques for Volume Rendering of Scalar Fields
, 1998
"... The task of efficient rendering of today's volumetric datasets is still being tackled by several research groups around the world. A quick calculation of the amount of computation required for interactive rendering of a high resolution volume puts us in the teraflop range. Yet, the demand to supp ..."
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The task of efficient rendering of today's volumetric datasets is still being tackled by several research groups around the world. A quick calculation of the amount of computation required for interactive rendering of a high resolution volume puts us in the teraflop range. Yet, the demand to support such rendering capabilities is increasing due to emerging technologies such as virtual surgery simulation and rapid prototyping. There are five main approaches to overcoming this seemingly insurmountable performance barrier: (i) data reduction by means of model extraction or data simplification, (ii) realization of specialpurpose volume rendering engines, (iii) softwarebased algorithm optimization and acceleration, (iv) implementation on general purpose parallel architectures, and (v) use of contemporary oftheshelf graphics hardware. In this presentation we first describe the vision of realtime highresolution volume rendering and estimate the computing power it demands. W...
Mix&Match: A Construction Kit for Scientific Visualization
, 1995
"... ix Preface x Acknowledgements : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : x Publication History : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : xi 1. Introduction 1 2. Scientific Visualization: Environments 5 2.1 Some Scientific Visualization Environme ..."
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ix Preface x Acknowledgements : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : x Publication History : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : xi 1. Introduction 1 2. Scientific Visualization: Environments 5 2.1 Some Scientific Visualization Environments : : : : : : : : : : : : : : : : : : 5 2.1.1 Turnkey Visualization Systems : : : : : : : : : : : : : : : : : : : : : 6 2.1.2 Extensible Visualization Systems : : : : : : : : : : : : : : : : : : : : 7 2.2 Spray Rendering : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 13 2.3 How Mix&Match relates to other environments and spray rendering : : : : 14 3. Scientific Visualization: Techniques 17 3.1 Scientific Data : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 17 3.2 A Classification : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 18 3.3 Two Dimensional Visualization : : : : : : : : : : : : : : : : : : : : : : : : : 21 3.4 Volume Visua...