Stereoscopic display is a fundamental part of virtual reality HMD systems and HTD (head-tracked display) systems such as the virtual workbench and the CAVE. A common practice in stereoscopic systems is deliberate incorrect modeling of user eye separation. Underestimating eye separation is frequently necessary for the human visual system to fuse stereo image pairs into single 3D images, while overestimating eye separation enhances image depth. Unfortunately, fals...

Currently almost all computer graphic stereoscopic images are generated by doubling the work required to create a single image. In this paper we derive and analyze algorithms for simultaneous generation of the two views necessary for a stereoscopic image. We begin with a discussion of the similarities of the two perspective views of a stereo pair. Following this, several graphics algorithms that have been optimized from known single-view methods are described and performance results obtained from testing the new stereo algorithms against the originals are presented. Categories and Subject Descriptors: I.3.2 [Computer Graphics]: Graphics Systems-- stereoscopic display system, display algorithms; I.3.3 [Computer Graphics]: Picture/Image Generation--display algorithms; I.3.6 [Computer Graphics]: Methodology and Techniques-- visual communication, visual perception; I.3.7 [Computer Graphics]: Three-Dimensional Graphics and Realism--stereoscopic graphics, three-dimensional display, visual pe...

Integrating the slope and setup calculations for triangles to the rasterizer offloads the host processor from intensive calculations and can significantly increase 3D system performance. The processing on the host is greatly reduced and much less data is passed from the host to the graphics subsystem. A setup architecture handling generalized triangle meshes and computing all necessary parameters for a high-end raster pipeline to generate Gouraud shaded, texture- and bumpmapped triangles is described and its benefits on the final bandwidth are shown. To efficiently compute the slopes and color gradients for each triangle, some implementation aspects on division and multiplication pipelines are discussed. The Setup for Triangle Rasterization Anders Kugler University of Tübingen - Computer Graphics Laboratory (1) (1) Universität Tübingen Wilhelm-Schickard-Institut für Informatik Graphisch-Interaktive Systeme Auf der Morgenstelle 10 D-72076 Tübingen - Germany email: kugler@gris.uni-t...

\Head-coupled stereo display " refers to the use of a standard graphics workstation to display stereo images of three-dimensional scenes using perspective projections de ned dynamically by the positions of the observer's eyes. The user is presented with a virtual scene located within or in front of the workstation monitor and can move his or her head around to obtain di erent views. We discuss the characteristics of head-coupled stereo display, the issues involved in implementing it correctly, and three experiments that were conducted to investigate the value of this type of display. The rst two experiments tested user performance under di erent viewing conditions. The two variables were (a) whether or not stereoscopic display was used and (b) whether or not head-coupled perspective was used. In the rst experiment, subjects were asked to subjectively rank the quality of the viewing conditions through pairwise comparisons. The results showed a strong acceptance of head-coupled stereo and a preference for headcoupling

In current Virtual Environment systems, the stereoscopic images presented in a Head-Mounted Display are far from optimal. The aim is to achieve orthostereoscopy, which roughly means images should "behave as in real life". A theoretical model developed by Robinett and Rolland [RR91] was used to implement a stereoscopy test system, allowing the independent setting of many stereoscopy related parameters. Tests aiming to optimize these parameters were devised. This paper reviews the theoretical model, then describes its implementation and the conducted tests. It ends with the test results and the conclusions that may be drawn from them. 1 Introduction Especially in more serious VE applications such as simulation and training systems it is essential that the environment mimics its real counterpart as much as possible. This includes a realistic three-dimensional image of the environment. Ideally, the image is orthostereoscopic, or as Sutherland states: "The image presented by the threedim...

The PlatoCAVE, the MiniCAVE, and the C2 are immersive stereoscopic projection-- based virtual reality environments oriented toward group interactions. As such they are particularly suited to collaborative efforts in data analysis and visual data mining. In this paper, we provide an overview of virtual reality in general, including immersive projection technology, and the use of stereoscopic displays for data visualization. We discuss design considerations for the construction of these immersive environments including 1--wall versus 4--wall implementations, augmented reality, stereoscopic placement, head tracking, the use of LCD devices, polarized light stereo, voice control, and image synchronization.

Recently, there has been a great increase in interest in using three dimensional stereoscopic displays to provide viewers with realistic 3D views of objects of interest. Some applications where stereoscopic displays are becoming popular include medical visualization, visualization of meteorological data, and various virtual reality applications. To quantify the effectiveness of stereoscopic systems over conventional monoscopic systems, well-designed experiments and data analysis methods are necessary. This task requires the combined effort of application scientists and experts in experimental design. Lack of interdisciplinary collaboration is a primary weakness of many stereoscopic display studies, resulting in the neglect of many important but subtle experimental issues. In this paper, we discuss specific issues that arise in the design of studies to determine the effectiveness of digital stereo imagery. Issues concerning statistical analysis of the experimental data are also discusse...

Abstract—Visualization of large geometric environments has always been an important problem of computer graphics. In this paper, we present a framework for the stereoscopic view-dependent visualization of large scale terrain models. We use a quadtree based multiresolution representation for the terrain data. This structure is queried to obtain the view-dependent approximations of the terrain model at different levels of detail. In order not to lose depth information, which is crucial for the stereoscopic visualization, we make use of a different simplification criterion, namely, distance-based angular error threshold. We also present an algorithm for the construction of stereo pairs in order to speed up the view-dependent stereoscopic visualization. The approach we use is the simultaneous generation of the triangles for two stereo images using a single draw-list so that the view frustum culling and vertex activation is done only once for each frame. The cracking problem is solved using the dependency information stored for each vertex. We eliminate the popping artifacts that can occur while switching between different resolutions of the data using morphing. We implemented the proposed algorithms on personal computers and graphics workstations. Performance experiments show that the second eye image can be produced approximately 45 percent faster than drawing the two images separately and a smooth stereoscopic visualization can be achieved at interactive frame rates using continuous multiresolution representation of height fields. Index Terms—Stereoscopic visualization, terrain height fields, multiresolution rendering, quadtrees. 1

Stereoscopic display is a fundamental part of many virtual reality systems. Stereoscopic displays render two perspective views of a scene, each of which is seen by one eye of the user. Ideally the user's natural visual system combines the stereo image pairs and the user perceives a single 3D image. In practice, however, users can have difficulty fusing the stereo image pairs into a single 3D image. Researchers have used a number of software methods to reduce fusion problems. Some fusion algorithms act directly on the 3D geometry while others act indirectly on the projected 2D images or the view parameters. Compared to the direct techniques, the indirect techniques tend to alter the projected 2D images to a lesser degree. However while the 3D image effects of the direct techniques are algorithmically specified, the 3D effects of the indirect techniques require further analysis. This is important because fusion techniques were developed in non-head-tracked displays that have distortion p...

In virtual environment systems, the ultimate goal is delivery of the highest-fidelity user experience possible. This dissertation shows that is possible to increase the scalability of distributed virtual environments (DVEs), in a tractable fashion, through a novel application of optimization techniques. Fidelity is maximized by utilizing the given display and network capacity in an optimal fashion, individually tuned for multiple users, in a manner most appropriate to a specific DVE application. This optimization is accomplished using the QUICK framework for managing the display and request of representations for virtual objects. Ratings of representation Quality, object Importance, and representation Cost are included in model descriptions as special annotations. The QUICK optimization computes the fidelity contribution of a representation by combining these annotations with specifications of user task and platform capability. This dissertation contributes the QUICK optimizati...