On porting software visualization tools to the web

Software systems are hard to understand due to the complexity and the sheer size of the data to be analyzed. Software visualization tools are a great help as they can sum up large quantities of data in dense, meaningful pictures. Traditionally, such tools come in the form of desktop applications. Modern web frameworks are about to change this status quo, as building software visualization tools as web applications can help in making them available to a larger audience in a collaborative setting. Such a migration comes with a number of promises, perils, and technical implications that must be considered before starting any migration process. In this paper, we share our experiences in porting two such tools to the web and provide guidelines about the porting. In particular, we discuss promises and perils that go hand in hand with such an endeavor and present a number of technological alternatives that are available to implement web-based visualization

Modelling Participation in Virtual Environments

Submitted to the University of London for the Degree of Doctor of Philosophy in Computer Science

Detection and representation of moving objects for video surveillance

In this dissertation two new approaches have been introduced for the automatic detection of moving objects (such as people and vehicles) in video surveillance sequences. The first technique analyses the original video and exploits spatial and temporal information to find those pixels in the images that correspond to moving objects. The second technique analyses video sequences that have been encoded according to a recent video coding standard (H.264/AVC). As such, only the compressed features are analyzed to find moving objects. The latter technique results in a very fast and accurate detection (up to 20 times faster than the related work). Lastly, we investigated how different XML-based metadata standards can be used to represent information about these moving objects. We proposed the usage of Semantic Web Technologies to combine information described according to different metadata standards

Augmented reality system with application in physical rehabilitation

The aging phenomenon causes increased physiotherapy services requirements, with increased costs associated with long rehabilitation periods. Traditional rehabilitation methods rely on the subjective assessment of physiotherapists without supported training data. To overcome the shortcoming of traditional rehabilitation method and improve the efficiency of rehabilitation, AR (Augmented Reality) which represents a promissory technology that provides an immersive interaction with real and virtual objects is used. The AR devices may assure the capture body posture and scan the real environment that conducted to a growing number of AR applications focused on physical rehabilitation. In this MSc thesis, an AR platform used to materialize a physical rehabilitation plan for stroke patients is presented. Gait training is a significant part of physical rehabilitation for stroke patients. AR represents a promissory solution for training assessment providing information to the patients and physiotherapists about exercises to be done and the reached results. As part of MSc work an iOS application was developed in unity 3D platform. This application immersing patients in a mixed environment that combine real-world and virtual objects. The human computer interface is materialized by an iPhone as head-mounted 3D display and a set of wireless sensors for physiological and motion parameters measurement. The position and velocity of the patient are recorded by a smart carpet that includes capacitive sensors connected to a computation unit characterized by Wi-Fi communication capabilities. AR training scenario and the corresponding experimental results are part of the thesis.O envelhecimento causa um aumento das necessidades dos serviços de fisioterapia, com aumento dos custos associados a longos períodos de reabilitação. Os métodos tradicionais de reabilitação dependem da avaliação subjetiva de fisioterapeutas sem registo automatizado de dados de treino. Com o principal objetivo de superar os problemas do método tradicional e melhorar a eficiência da reabilitação, é utilizada a RA (Realidade Aumentada), que representa uma tecnologia promissora, que fornece uma interação imersiva com objetos reais e virtuais. Os dispositivos de RA são capazes de garantir uma postura correta do corpo de capturar e verificar o ambiente real, o que levou a um número crescente de aplicações de RA focados na reabilitação física. Neste projeto, é apresentada uma plataforma de RA, utilizada para materializar um plano de reabilitação física para pacientes que sofreram AVC. O treino de marcha é uma parte significativa da reabilitação física para pacientes com AVC. A RA apresenta-se como uma solução promissora para a avaliação do treino, fornecendo informações aos pacientes e aos profissionais de fisioterapia sobre os exercícios a serem realizados e os resultados alcançados. Como parte deste projeto, uma aplicação iOS foi desenvolvida na plataforma Unity 3D. Esta aplicação fornece aos pacientes um ambiente imersivo que combina objetos reais e virtuais. A interface de RA é materializada por um iPhone montado num suporte de cabeça do utilizador, assim como um conjunto de sensores sem fios para medição de parâmetros fisiológicos e de movimento. A posição e a velocidade do paciente são registadas por um tapete inteligente que inclui sensores capacitivos conectados a uma unidade de computação, caracterizada por comunicação via Wi-Fi. O cenário de treino em RA e os resultados experimentais correspondentes fazem parte desta dissertação

Evaluating Extensible 3D (X3D) Graphics For Use in Software Visualisation

3D web software visualisation has always been expensive, special purpose, and hard to program. Most of the technologies used require large amounts of scripting, are not reliable on all platforms, are binary formats, or no longer maintained. We can make end-user web software visualisation of object-oriented programs cheap, portable, and easy by using Extensible (X3D) 3D Graphics, which is a new open standard. In this thesis we outline our experience with X3D and discuss the suitability of X3D as an output format for software visualisation

Ontologies for context-aware applications

Tese de mestrado integrado. Engenharia Electrotécnica e de Computadores. Faculdade de Engenharia. Universidade do Porto. 200

Integrating realistic human group behaviors into a networked 3D virtual environment

Distributed Interactive Simulation DIS-Java-VRML Working Group. Includes supplementary material provided from the contents of a CD-Rom issued containing the work of all three Working Group members and all supplementary material, in compressed format.Virtual humans operating inside large-scale virtual environments (VE) are typically controlled as single entities. Coordination of group activity and movement is usually the responsibility of their real world human controllers. Georeferencing coordinate systems, single-precision versus double-precision number representation and network delay requirements make group operations difficult. Mounting multiple humans inside shared or single vehicles, (i.e. air-assault operations, mechanized infantry operations, or small boat/riverine operations) with high fidelity is often impossible. The approach taken in this thesis is to reengineer the DIS-Java-VRML Capture the Flag game geolocated at Fort Irwin, California to allow the inclusion of human entities. Human operators are given the capability of aggregating or mounting nonhuman entities for coordinated actions. Additionally, rapid content creation of human entities is addressed through the development of a native tag set for the Humanoid Animation (H-Anim) 1.1 Specification in Extensible 3D (X3D). Conventions are demonstrated for integrating the DIS-Java-VRML and H-Anim draft standards using either VRML97 or X3D encodings. The result of this work is an interface to aggregate and control articulated humans using an existing model with a standardized motion library in a networked virtual environment. Virtual human avatars can be mounted and unmounted from aggregation entities. Simple demonstration examples show coordinated tactical maneuver among multiple humans with and without vehicles. Live 3D visualization of animated humanoids on realistic terrain is then portrayed inside freely available web browsers.Approved for public release; distribution is unlimited

Task-based Adaptation of Graphical Content in Smart Visual Interfaces

To be effective visual representations must be adapted to their respective context of use, especially in so-called Smart Visual Interfaces striving to present specifically those information required for the task at hand. This thesis proposes a generic approach that facilitate the automatic generation of task-specific visual representations from suitable task descriptions. It is discussed how the approach is applied to four principal content types raster images, 2D vector and 3D graphics as well as data visualizations, and how existing display techniques can be integrated into the approach.Effektive visuelle Repräsentationen müssen an den jeweiligen Nutzungskontext angepasst sein, insbesondere in sog. Smart Visual Interfaces, welche anstreben, möglichst genau für die aktuelle Aufgabe benötigte Informationen anzubieten. Diese Arbeit entwirft einen generischen Ansatz zur automatischen Erzeugung aufgabenspezifischer Darstellungen anhand geeigneter Aufgabenbeschreibungen. Es wird gezeigt, wie dieser Ansatz auf vier grundlegende Inhaltstypen Rasterbilder, 2D-Vektor- und 3D-Grafik sowie Datenvisualisierungen anwendbar ist, und wie existierende Darstellungstechniken integrierbar sind