Image database system for glaucoma diagnosis support

Tato práce popisuje přehled standardních a pokročilých metod používaných k diagnose glaukomu v ranném stádiu. Na základě teoretických poznatků je implementován internetově orientovaný informační systém pro oční lékaře, který má tři hlavní cíle. Prvním cílem je možnost sdílení osobních dat konkrétního pacienta bez nutnosti posílat tato data internetem. Druhým cílem je vytvořit účet pacienta založený na kompletním očním vyšetření. Posledním cílem je aplikovat algoritmus pro registraci intenzitního a barevného fundus obrazu a na jeho základě vytvořit internetově orientovanou tři-dimenzionální vizualizaci optického disku. Tato práce je součásti DAAD spolupráce mezi Ústavem Biomedicínského Inženýrství, Vysokého Učení Technického v Brně, Oční klinikou v Erlangenu a Ústavem Informačních Technologií, Friedrich-Alexander University, Erlangen-Nurnberg.This master thesis describes a conception of standard and advanced eye examination methods used for glaucoma diagnosis in its early stage. According to the theoretical knowledge, a web based information system for ophthalmologists with three main aims is implemented. The first aim is the possibility to share medical data of a concrete patient without sending his personal data through the Internet. The second aim is to create a patient account based on a complete eye examination procedure. The last aim is to improve the HRT diagnostic method with an image registration algorithm for the fundus and intensity images and create an optic nerve head web based 3D visualization. This master thesis is a part of project based on DAAD co-operation between Department of Biomedical Engineering, Brno University of Technology, Eye Clinic in Erlangen and Department of Computer Science, Friedrich-Alexander University, Erlangen-Nurnberg.

Web Services en el contexto de la Visualización de Grandes Volúmenes de Datos

Gracias a los crecientes avances tecnológicos se aprecia un crecimiento exponencial en densidad y tamaño de los volúmenes de datos; la visualización de tales cantidades de datos puede sobrepasar rápidamente el poder de procesamiento local. Con la disponibilidad de la GRID, la ubicuidad de Internet y el soporte de los Web Services se han propuesto varios sistemas de visualización distribuida que asisten a científicos y usuarios de todo el mundo. Sin embargo, algunos de estos sistemas se han planteado desde el punto de vista de la colaboración a distancia y otros desde el punto de vista de compartir recursos; debido a esto, los sistemas existentes no están preparados para manejar volúmenes de datos realmente grandes. Para contar con un sistema de Visualización en la Web es imperativo hacer uso eficiente de la red; la estrategia consiste en transmitir solo las porciones de datos que serán procesadas y visualizadas; esto implica crear una representación de datos adecuada que permita extraer datos con diversos niveles de detalle para poder transmitirlos y visualizarlos progresivamente. Finalmente esto debe integrarse en un sistema de caché distribuido que evite retransmisiones innecesarias y haga que los datos residan más tiempo donde más se necesitan.Eje: Computación gráfica, visualización e imágenesRed de Universidades con Carreras en Informática (RedUNCI

Deploying Web-based Visual Exploration Tools on the Grid

We discuss a web-based portal for the exploration, encapsulation, and dissemination of visualization results over the Grid. This portal integrates three components: an interface client for structured visualization exploration, a visualization web application to manage the generation and capture of the visualization results, and a centralized portal application server to access and manage grid resources. Our approach uses standard web technologies to make the system accessible with minimal user setup. We demonstrate the usefulness of the developed system using an example for Adaptive Mesh Refinement (AMR) data visualization

Servicios web para rendering de volúmenes no estructurados

La visualización de mallas tetraédricas no estructuradas ha probado ser costosa en términos computacionales y puede fácilmente sobrepasar la capacidad de procesamiento local. En este trabajo describimos el diseño general así como los detalles de implementación de un servicio de visualización remota capaz de procesar datos volumétricos no estructurados. Concretamente nos centramos en la exposición del proceso de rendering como Servicio Web. Analizamos las distintas interacciones entre las aplicaciones cliente y el servicio y todos los flujos de datos recibidos y enviados por el servicio como mensajes SOAP. Asimismo, proveemos al usuario de una interfase visual que suple la falta de interactividad de los Servicios Web mostrando así la factibilidad de esta arquitectura.The visualization of unstructured tetrahedral meshes has been proven to be costly in terms of computational resources and it can easily overcome the local computer’s capacity. In this work we describe the general design and implementation details of a remote visualization service able to deal with unstructured volumetric data. Specifically we focus on exposing the rendering process as a Web Service. We analyze different interactions between client applications and the service, and the entire data flow received and sent by the service as SOAP messages. Moreover, we provide an interactive graphical user interface for filling the leak of interactivity of Web Services, showing the feasibility of this architecture.IV Workshop de Computación Gráfica, Imágenes y Visualización (WCGIV)Red de Universidades con Carreras en Informática (RedUNCI

3D Multi-user interactive visualization with a shared large-scale display

When the multiple users interact with a virtual environment on a largescale display there are several issues that need to be addressed to facilitate the interaction. In the thesis, three main topics for collaborative visualization are discussed; display setup, interactive visualization, and visual fatigue. The problems that the author is trying to address in this thesis are how multiple users can interact with a shared large-scale display depending on the display setups and how they can interact with the shared visualization in a way that doesn’t lead to visual fatigue. The first user study (Chapter 3) explores the display setups for multi-user interaction with a shared large-display. The author describes the design of the three main display setups (a shared view, a split screen, and a split screen with navigation information) and a demonstration using these setups. The user study found that the split screen and the split screen with navigation information can improve users’ confidence and reduce frustration level and are more preferred than a shared view. However, a shared view can still provide effective interaction and collaboration and the display setups cannot have a large impact on usability and workload. From the first study, the author employed a shared view for multi-user interactive visualization with a shared large-scale display due to the advantages of the shared view. To improve interactive visualization with a shared view for multiple users, the author designed and conducted the second user study (Chapter 4). A conventional interaction technique, the mean tracking method, was not effective for more than three users. In order to overcome the limitation of the current multi-user interactive visualization techniques, two interactive visualization techniques (the Object Shift Technique and Activity-based Weighted Mean Tracking method) were developed and were evaluated in the second user study. The Object Shift Technique translates the virtual objects in the opposite direction of movement of the Point of View (PoV) and the Activity-based Weighted Mean Tracking method assigns the higher weight to active users in comparison with stationary users to determine the location of the PoV. The results of the user study showed that these techniques can support collaboration, improve interactivity, and provide similar visual discomfort compared to the conventional method. The third study (Chapter 5) describes how to reduce visual fatigue for 3D stereoscopic visualization with a single point of view (PoV). When multiple users interact with 3D stereoscopic VR using multi-user interactive visualization techniques and they are close to the virtual objects, they can perceive 3D visual fatigue from the large disparity. To reduce the 3D visual fatigue, an Adaptive Interpupillary Distance (Adaptive IPD) adjustment technique was developed. To evaluate the Adaptive IPD method, the author compared to traditional 3D stereoscopic and the monoscopic visualization techniques. Through the user experiments, the author was able to confirm that the proposed method can reduce visual discomfort, yet maintain compelling depth perception as the result provided the most preferable 3D stereoscopic visualization experience. For these studies, the author developed a software framework and designed a set of experiments (Chapter 6). The framework architecture that contains the three main ideas are described. A demonstration application for multidimensional decision making was developed using the framework. The primary contributions of this thesis include a literature review of multiuser interaction with a shared large-scale display, deeper insights into three display setups for multi-user interaction, development of the Object Shift Techniques, the Activity-based Weighted Mean Tracking method, and the Adaptive Interpupillary Distance Adjustment technique, the evaluation of the three novel interaction techniques, development of a framework for supporting a multi-user interaction with a shared large-scale display and its application to multi-dimensional decision making VR system

Autonomic visualisation.

This thesis introduces the concept of autonomic visualisation, where principles of autonomic systems are brought to the field of visualisation infrastructure. Problems in visualisation have a specific set of requirements which are not always met by existing systems. The first half of this thesis explores a specific problem for large scale visualisation; that of data management. Visualisation algorithms have somewhat different requirements to other external memory problems, due to the fact that they often require access to all, or a large subset, of the data in a way that is highly dependent on the view. This thesis proposes a knowledge-based approach to pre-fetching in this context, and presents evidence that such an approach yields good performance. The knowledge based approach is incorporated into a five-layer model, which provides a systematic way of categorising and designing out-of-core, or external memory, systems. This model is demonstrated with two example implementations, on in the local and one in the remote context. The second half explores autonomic visualisation in the more general case. A simulation tool, created for the purpose of designing autonomic visualisation infrastructure is presented. This tool, SimEAC, provides a way of facilitating the development of techniques for managing large-scale visualisation systems. The abstract design of the simulation system, as well as details of the implementation are presented. The architecture of the simulator is explored, and then the system is evaluated in a number of case studies indicating some of the ways in which it can be used. The simulator provides a framework for experimentation and rapid prototyping of large scale autonomic systems

Interactive HTML

As the World Wide Web continues to grow, people clearly want to do much more with it than just publish static pages of text and graphics. While such increased interactivity has traditionally been accomplished through the use of server-side CGI scripts, much recent research on Web browsers has been on extending their capabilities through the addition of various types of client-side services. The most popular of these extensions take the form of plug-ins, applets, and "document scripts" such as Java Script. However, because these extensions have been created in a haphazard way by a variety of independent groups, they suffer greatly in terms of flexibility, uniformity, and interoperability. Interactive HTML is a system that addresses these problems by combining plug-ins, applets, and document scripts into one uniform and cohesive architecture. It is implemented as an external C library that can be used by a browser programmer to add client-side services to the browser. The IHTML services are implemented as dynamically loaded "language modules," allowing new plug-ins and language interpreters to be added to an iHTML browser without recompiling the browser itself. The system is currently integrated with NCSA's X Mosaic browser and includes language modules for a text viewer plug-in and Python language interpreter. This thesis examines the iHTML architecture in the context of the historical development of Web client-side services and presents an example of iHTML's use to collect usage information about Web documents