12 research outputs found
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Interactive, Internet Delivery of Visualization via Structured,Prerendered multiresolution Imagery
One of the fundamental problems in remote visualization --where I/O and data intensive visualization activities take place at acentrally located supercomputer center and resulting imagery is deliveredto a remotely located user -- is reduced interactivity resulting from thecombination of high network latency and relatively low network bandwidth.This research project has produced a novel approach for latency-tolerantdelivery of visualization and rendering results where client-side framerate display performance is independent of source dataset size, imagesize, visualization technique or rendering complexity. As such, it is asuitable solution for remote visualization image delivery for anyvisualization or rendering application that can generate image frames inan ordered fashion. This new capability is suitable for use in addressingmany of ASCR s remote visualization needs, particularly deployment atopen computing facilities to provide remote visualization capabilities toteams of scientific researchers
Supercomputing visualization made simple
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.Includes bibliographical references (p. [39]-[40]).In this thesis, we propose a solution for remote visualization for supercomputers. Our solution consists of two tools that help users visualize data from high performance computers. The first one takes advantage of the Web and AJAX technology [25], is simple, light weight and does not require any pre-installation which can be a perfect tool for demonstration supercomputing data. The second tool, a 3D Viewer on MATLAB Star-P [8], is to utilize more resources in the user's workstation to achieve better quality visualization and more flexibility in data navigation and analysis. Both solutions strive to create a simple and user-friendly framework that supports researchers' goals to create, analyze, test and debug numerical algorithms in supercomputing world.by Huy Nguyen.S.M
Reducing Occlusion in Cinema Databases through Feature-Centric Visualizations
In modern supercomputer architectures, the I/O capabilities do not keep up with the computational speed. Image-based techniques are one very promising approach to a scalable output format for visual analysis, in which a reduced output that corresponds to the visible state of the simulation is rendered in-situ and stored to disk. These techniques can support interactive exploration of the data through image compositing and other methods, but automatic methods of highlighting data and reducing clutter can make these methods more effective. In this paper, we suggest a method of assisted exploration through
the combination of feature-centric analysis with image space techniques and show how the reduction of the data to features of interest reduces occlusion in the output for a set of example applications
Web-based Stereo Rendering for Visualization and Annotation of Scientific Volumetric Data
Advancement in high-throughput microscopy technology such as the Knife-Edge
Scanning Microscopy (KESM) is enabling the production of massive amounts of high-resolution
and high-quality volumetric data of biological microstructures. To fully
utilize these data, they should be efficiently distributed to the scientific research community
through the Internet and should be easily visualized, annotated, and analyzed.
Given the volumetric nature of the data, visualizing them in 3D is important. However,
since we cannot assume that every end user has high-end hardware, an approach
that has minimal hardware and software requirements will be necessary, such as a
standard web browser running on a typical personal computer. There are several web
applications that facilitate the viewing of large collections of images. Google Maps
and Google Maps-like interfaces such as Brainmaps.org allow users to pan and zoom
2D images efficiently. However, they do not yet support the rendering of volumetric
data in their standard web interface.
The goal of this thesis is to develop a light-weight volumetric image viewer using
existing web technologies such as HTML, CSS and JavaScript while exploiting the
properties of stereo vision to facilitate the viewing and annotations of volumetric data.
The choice of stereogram over other techniques was made since it allows the usage of
raw image stacks produced by the 3D microscope without any extra computation on
the data at all. Operations to generate stereo images using 2D image stacks include
distance attenuation and binocular disparity. By using HTML and JavaScript that are computationally cheap, we can accomplish both tasks dynamically in a standard
web browser, by overlaying the images with intervening semi-opaque layers.
The annotation framework has also been implemented and tested. In order for
annotation to work in this environment, it should also be in the form of stereogram
and should aid the merging of stereo pairs. The current technique allows users to
place a mark (dot) on one image stack, and its projected position onto the other
image stack is calculated dynamically on the client side. Other extra metadata such
as textual descriptions can be entered by the user as well. To cope with the occlusion
problem caused by changes in the z direction, the structure traced by the user will
be displayed on the side, together with the data stacks. Using the same stereo-gram
creation techniques, the traces made by the user is dynamically generated and shown
as stereogram.
We expect the approach presented in this thesis to be applicable to a broader
scientific domain, including geology and meteorology
Modélisation et distribution adaptatives de grandes scènes naturelles
Cette thèse traite de la modélisation et la diffusion de grandes scènes 3D naturelles. Nous visons à fournir des techniques pour permettre à des utilisateurs de naviguer à distance dans une scène 3D naturelle, tout en assurant la cohérence botanique et l'interactivité. Tout d'abord, nous fournissons une technique de compression multi-résolution, fondée sur la normalisation, l'instanciation, la décorrélation, et sur le codage entropique des informations géometriques pour des modèles de plantes. Ensuite, nous étudions la transmission efficace de ces objets 3D. L'algorithme de paquétisation proposé fonctionne pour la plupart des représentations multi-résolution d'objet 3D. Nous validons les techniques de paquétisation par des expériences sur un WAN (Wide Area Network), avec et sans contrôle de congestion (Datagram Congestion Control Protocol). Enfin, nous abordons les questions du streaming au niveau de la scène. Nous optimisons le traitement des requêtes du côté serveur en fournissant une structure de données adaptée et nous préparons le terrain pour nos travaux futurs sur l'évolutivité et le déploiement de systèmes distribués de streaming 3D. ABSTRACT : This thesis deals with the modeling and the interactive streaming of large natural 3D scenes. We aim at providing techniques to allow the remote walkthrough of users in a natural 3D scene ensuring botanical coherency and interactivity.First, we provide a compact and progressive representation for botanically realistic plant models. The topological structure and the geometry of the plants are represented by generalized cylinders. We provide a multi-resolution compression scheme, based on standardization and instantiation, on difference-based decorrelation, and on entropy coding. Then, we study efficient transmission of these 3D objects. The proposed packetization scheme works for any multi-resolution 3D representation. We validate our packetization schemes with extensive experiments over a WAN (Wide Area Network), with and without congestion control (Datagram Congestion Control Protocol). Finally, we address issues on streaming at the scene-level. We optimize the viewpoint culling requests on server-side by providing an adapted datastructure and we prepare the ground for our further work on scalability and deployment of distributed 3D streaming systems
Web-based Stereoscopic Collaboration for Medical Visualization
Medizinische Volumenvisualisierung ist ein wertvolles Werkzeug zur Betrachtung von Volumen- daten in der medizinischen Praxis und Lehre. Eine interaktive, stereoskopische und kollaborative Darstellung in Echtzeit ist notwendig, um die Daten vollständig und im Detail verstehen zu können. Solche Visualisierung von hochauflösenden Daten ist jedoch wegen hoher Hardware- Anforderungen fast nur an speziellen Visualisierungssystemen möglich. Remote-Visualisierung wird verwendet, um solche Visualisierung peripher nutzen zu können. Dies benötigt jedoch fast immer komplexe Software-Deployments, wodurch eine universelle ad-hoc Nutzbarkeit erschwert wird. Aus diesem Sachverhalt ergibt sich folgende Hypothese: Ein hoch performantes Remote- Visualisierungssystem, welches für Stereoskopie und einfache Benutzbarkeit spezialisiert ist, kann für interaktive, stereoskopische und kollaborative medizinische Volumenvisualisierung genutzt werden.
Die neueste Literatur über Remote-Visualisierung beschreibt Anwendungen, welche nur reine Webbrowser benötigen. Allerdings wird bei diesen kein besonderer Schwerpunkt auf die perfor- mante Nutzbarkeit von jedem Teilnehmer gesetzt, noch die notwendige Funktion bereitgestellt, um mehrere stereoskopische Präsentationssysteme zu bedienen. Durch die Bekanntheit von Web- browsern, deren einfach Nutzbarkeit und weite Verbreitung hat sich folgende spezifische Frage ergeben: Können wir ein System entwickeln, welches alle Aspekte unterstützt, aber nur einen reinen Webbrowser ohne zusätzliche Software als Client benötigt?
Ein Proof of Concept wurde durchgeführt um die Hypothese zu verifizieren. Dazu gehörte eine Prototyp-Entwicklung, deren praktische Anwendung, deren Performanzmessung und -vergleich.
Der resultierende Prototyp (CoWebViz) ist eines der ersten Webbrowser basierten Systeme, welches flüssige und interaktive Remote-Visualisierung in Realzeit und ohne zusätzliche Soft- ware ermöglicht. Tests und Vergleiche zeigen, dass der Ansatz eine bessere Performanz hat als andere ähnliche getestete Systeme. Die simultane Nutzung verschiedener stereoskopischer Präsen- tationssysteme mit so einem einfachen Remote-Visualisierungssystem ist zur Zeit einzigartig. Die Nutzung für die normalerweise sehr ressourcen-intensive stereoskopische und kollaborative Anatomieausbildung, gemeinsam mit interkontinentalen Teilnehmern, zeigt die Machbarkeit und den vereinfachenden Charakter des Ansatzes. Die Machbarkeit des Ansatzes wurde auch durch die erfolgreiche Nutzung für andere Anwendungsfälle gezeigt, wie z.B. im Grid-computing und in der Chirurgie
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Interactive, internet delivery of visualization via structured prerendered multiresolution imagery.
We present a novel approach for latency-tolerant delivery of visualization and rendering results where client-side frame rate display performance is independent of source dataset size, image size, visualization technique or rendering complexity. Our approach delivers pre-rendered, multiresolution images to a remote user as they navigate through different viewpoints, visualization or rendering parameters. We employ demand-driven tiled, multiresolution image streaming and prefetching to efficiently utilize available bandwidth while providing the maximum resolution user can perceive from a given viewpoint. Since image data is the only input to our system, our approach is generally applicable to all visualization and graphics rendering applications capable of generating image files in an ordered fashion. In our implementation, a normal web server provides on-demand images to a remote custom client application, which uses client-pull to obtain and cache only those images required to fulfill the interaction needs. The main contributions of this work are: (1) an architecture for latency-tolerant, remote delivery of precomputed imagery suitable for use with any visualization or rendering application capable of producing images in an ordered fashion; (2) a performance study showing the impact of diverse network environments and different tunable system parameters on end-to-end system performance in terms of deliverable frames per second