Made available in DSpace on 2016-04-26T18:10:09Z (GMT). No. of bitstreams: 1 Gustavo Augusto Tavares Cavalheiro.pdf: 1998955 bytes, checksum: 08e4882e5f83d251d445152ccc759d12 (MD5) Previous issue date: 2010-09-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Based on the analisys of the historical and cultural relationship that, in the literary heteronomy, is developed by the current propensity to the digital alterity, this study points out the similarities, differences and similitudes between the civil person, the cybercultural spectrum and images of "self-other". The presentation of the subject and the problem focus on questioning the construction and acceptance of the real/true in his overlaps of forged identification, which can be widely discussed in the pre-cybercultural period. Bringing to the comunication, the elements and concepts of being (far/close) yourself as much as the mediatic structures builds and/or translates the civil society as an imagery (re/a)presentation of yourself; is it studied the expansion of yourself in the digital space in a digital nets new time-untimed, from the image to the formation of an "other" (or personaskilled) and its seduction built under the logic of appearance design construction /management/power of an Avatar / Ante a análise da relação histórico-cultural que, situada na heteronímia literária, se desenvolve até a atual propensão à alteridade digital, o trabalho aponta as semelhanças, diferenças e similitudes, entre a persona civil, o espectro cibercultural e as imagens de um eu-outro . A apresentação do tema e do problema tem sob foco o questionamento da construção e aceitação cotidiana do real/verdadeiro no seu confronto com outras identificações forjadas, que podem ser amplamente encontradas e analisadas desde o período pré-cibercultural. Trazendo para a comunicação, elementos e conceitos de (di/e)star-se sobre a forma como as estruturas mediáticas constróem e/ou traduzem a sociedade civil em (re/a)presentações imagéticas de si, estuda-se sua expansão no espaço digital do novo tempodestemporializado das redes digitais, até a formação da imagem de um eu-outro (ou persona-hábil) e sua sedução, construídas sob a lógica do design da aparência/gestão/poder de um Avatar

Propiciar uma boa experiência de imersão ao usuário, quando este interage com conteúdos ou ambientes virtuais, é um dos principais desafios dos desenvolvedores e pesquisadores de tecnologias interativas, com destaque para realidade virtual e aumentada. Em especial nas áreas de educação e entretenimento, nas quais o engajamento do usuário e a significância dos conteúdos são cruciais para o sucesso da aplicação, é comum a busca por uma experiência que se aproxime de uma imersão total do participante. Quando as atividades envolvem interações a distância, um possível meio de se obter maior imersão são os chamados sistemas de telecomunicação imersiva. Tais sistemas oferecem compartilhamento de um ambiente virtual e troca de informações entre participantes remotos, além da interação desses com o ambiente. Um componente importante desses sistemas é o vídeo-avatar, uma representação visual do participante dentro do ambiente, baseado em sua captura de vídeo em tempo-real. Este trabalho apresenta novas propostas de reconstrução geométrica e renderização para a geração e apresentação de um vídeo-avatar. Inicialmente, um modelo teórico para se modularizar as técnicas de reconstrução e renderização existentes foi proposto. Por meio desse modelo foi criada uma nova técnica de reconstrução geométrica e renderização, denominada Video-based Microfacet Billboarding. Essa técnica emprega uma reconstrução e renderização em tempo-real que possibilita a representação de detalhes e melhora a percepção de integração com o ambiente. É também proposta neste trabalho o conceito de non-photorealistic video-avatar, que visa aplicar um estilo não fotorrealístico único sobre toda a cena, afim de melhorar a integração do avatar com o ambiente e, por sua vez, aumentar a imersão do usuário. Os resultados obtidos através da implementação do vídeo-avatar com essas técnicas e testes preliminares com usuários dão fortes indícios de que é possível a geração de uma representação visual que possua todos os requisitos do sistema iLive, sistema de telecomunicação imersiva voltado a educação e jogos eletrônicos em desenvolvimento pelo Laboratório de Tecnologias Interativas (Interlab) da Escola Politécnica da Universidade de São Paulo. / Providing good immersion experiences for users interacting with virtual contents or an environment is one of the main challenges for developers and researchers in interactive technologies, mainly virtual and augmented reality. Especially in areas of education and entertainment, in which the engagement of the user and the significance of content are of crucial importance for the success of the application, the search for experiences that approximate to one of a total immersion of the participant is common practice. When interaction at distance is necessary, one way to provide better immersion experiences is the use of a solution called Immersive Telecommunication System. This kind of system can provide the sharing of the virtual environment among participants, information exchange among them, and also their interaction with the virtual environment. One of the most important component of these systems is the video-avatar, the representation of the participant in the virtual environment based on a video of the participant captured in real-time. This work presents new approaches of geometric reconstruction and rendering for the creation of a video-avatar. First, a theoretical model to modularize the existing reconstruction and rendering approaches was proposed. Based on this model, a new approach of geometric reconstruction and rendering, called Video-based Microfacet Billboarding, was conceived. This approach uses a technique of real-time reconstruction and rendering that enables the representation of the object details and improves the integration of the avatar in the virtual environment. In this work, it is also proposed the concept of non-photorealistic video-avatar, that aims to apply a non-photorealistic style over all the scene to improve the avatar integration with the environment, and with this, to enhance the user\'s immersion. The results obtained by the implementation of a video-avatar with these approaches, as well as preliminary users tests, gives us strong evidences that we could create a user representation that attends all the requisites of the iLive system, an immersive telecommunication system for education and gaming purposes, in development by the Interactive Technologies Laboratory (Interlab) of Escola Politécnica da Universidade de São Paulo.

Propiciar uma boa experiência de imersão ao usuário, quando este interage com conteúdos ou ambientes virtuais, é um dos principais desafios dos desenvolvedores e pesquisadores de tecnologias interativas, com destaque para realidade virtual e aumentada. Em especial nas áreas de educação e entretenimento, nas quais o engajamento do usuário e a significância dos conteúdos são cruciais para o sucesso da aplicação, é comum a busca por uma experiência que se aproxime de uma imersão total do participante. Quando as atividades envolvem interações a distância, um possível meio de se obter maior imersão são os chamados sistemas de telecomunicação imersiva. Tais sistemas oferecem compartilhamento de um ambiente virtual e troca de informações entre participantes remotos, além da interação desses com o ambiente. Um componente importante desses sistemas é o vídeo-avatar, uma representação visual do participante dentro do ambiente, baseado em sua captura de vídeo em tempo-real. Este trabalho apresenta novas propostas de reconstrução geométrica e renderização para a geração e apresentação de um vídeo-avatar. Inicialmente, um modelo teórico para se modularizar as técnicas de reconstrução e renderização existentes foi proposto. Por meio desse modelo foi criada uma nova técnica de reconstrução geométrica e renderização, denominada Video-based Microfacet Billboarding. Essa técnica emprega uma reconstrução e renderização em tempo-real que possibilita a representação de detalhes e melhora a percepção de integração com o ambiente. É também proposta neste trabalho o conceito de non-photorealistic video-avatar, que visa aplicar um estilo não fotorrealístico único sobre toda a cena, afim de melhorar a integração do avatar com o ambiente e, por sua vez, aumentar a imersão do usuário. Os resultados obtidos através da implementação do vídeo-avatar com essas técnicas e testes preliminares com usuários dão fortes indícios de que é possível a geração de uma representação visual que possua todos os requisitos do sistema iLive, sistema de telecomunicação imersiva voltado a educação e jogos eletrônicos em desenvolvimento pelo Laboratório de Tecnologias Interativas (Interlab) da Escola Politécnica da Universidade de São Paulo. / Providing good immersion experiences for users interacting with virtual contents or an environment is one of the main challenges for developers and researchers in interactive technologies, mainly virtual and augmented reality. Especially in areas of education and entertainment, in which the engagement of the user and the significance of content are of crucial importance for the success of the application, the search for experiences that approximate to one of a total immersion of the participant is common practice. When interaction at distance is necessary, one way to provide better immersion experiences is the use of a solution called Immersive Telecommunication System. This kind of system can provide the sharing of the virtual environment among participants, information exchange among them, and also their interaction with the virtual environment. One of the most important component of these systems is the video-avatar, the representation of the participant in the virtual environment based on a video of the participant captured in real-time. This work presents new approaches of geometric reconstruction and rendering for the creation of a video-avatar. First, a theoretical model to modularize the existing reconstruction and rendering approaches was proposed. Based on this model, a new approach of geometric reconstruction and rendering, called Video-based Microfacet Billboarding, was conceived. This approach uses a technique of real-time reconstruction and rendering that enables the representation of the object details and improves the integration of the avatar in the virtual environment. In this work, it is also proposed the concept of non-photorealistic video-avatar, that aims to apply a non-photorealistic style over all the scene to improve the avatar integration with the environment, and with this, to enhance the user\'s immersion. The results obtained by the implementation of a video-avatar with these approaches, as well as preliminary users tests, gives us strong evidences that we could create a user representation that attends all the requisites of the iLive system, an immersive telecommunication system for education and gaming purposes, in development by the Interactive Technologies Laboratory (Interlab) of Escola Politécnica da Universidade de São Paulo.

Au cours des dernières années les Mondes Virtuels 3D (MV3D) sont devenus une réalité. Initialement considérés comme un nouveau moyen de communication sociale, initiés par le développement logiciel et matériel, les MV3Ds révèlent diverses fonctionnalités, des expériences et des connaissances. Étant la représentation de l'utilisateur, l'avatar est l’une des ressources les plus significatives et les plus complexes d'un monde virtuel. Une courte analyse d'un contenu de MV nous informe que le stockage/transmission est la partie la plus significative des ressources du MV. Dans l’ensemble des ressources, les avatars sont les structures les plus complexes, représentés par différents composants : géométrie, images, animations, etc. Donc, en abordant les problématiques de compression, d'adaptation et d'interopérabilité liées aux avatars, nous traitons implicitement presque tout type de ressources tifs qu’on pourrait retrouver dans les MVs. L'objectif global du développement d’outils et des méthodes, pour un déploiement élargi de MV, est traduit par les trois points spécifiques suivants: Proposer un framework de compression pour permettre le transfert efficace et compact d'avatars et de ressources graphiques 3D généraux. Spécifiquement pour des avatars, le framework devrait être indépendante avec un formalisme de représentation. Proposer une solution optimisée permettant l’accessibilité aux avatars sur des terminaux à faibles ressources tels que les téléphones portables. Définir un modèle de métadonnées permettant l'interopérabilité d'avatars entre différents MVs. Les trois objectifs sont traités dans ce manuscrit et pour chacun nous proposons des contributions originales. / In the last few years 3D Virtual Worlds (3DVWs) became a reality. Initially considered as a new mean for social communication, triggered by the development of software and hardware technology, 3DVWs are exposing now different functionalities, experiences and acquaintances. Therefore, they achieved their popularity very fast, indicated by the number and the progression of active users. Being the representation of the user, the avatar is one of the most significant and most complex assets of a Virtual World. A short analysis of a VW content allows one to observe that from the point of view of the storage/transmission the most significant amount is represented by the VW assets. Within the set of assets, the avatars are the most complex structures, consisting of different components: geometry, images, animations, structures, etc. The overall objective of developing tools and methods for a large deployment of VW are translated into three specific ones: To propose a compression framework to enable efficient, compact transfer of avatars, and general 3D graphics assets. Specifically for avatars, the framework should be independent from the representation formalism. To propose an optimized solution making the avatars accessible on weak terminals such as mobile phones. To define a metadata model allowing avatars interoperability between different VWs. The three objectives are addressed in this thesis and for each we propose original contributions.

Magister Scientiae - MSc / This thesis presents an approach for automatically generating signing animations from a sign language notation. An avatar endowed with expressive gestures, as subtle as changes in facial expression, is used to render the sign language animations. SWML, an XML format of SignWriting is provided as input. It transcribes sign language gestures in a format compatible to virtual signing. Relevant features of sign language gestures are extracted from the SWML. These features are then converted to body animation pa- rameters, which are used to animate the avatar. Using key-frame animation techniques, intermediate key-frames approximate the expected sign language gestures. The avatar then renders the corresponding sign language gestures. These gestures are realistic and aesthetically acceptable and can be recognized and understood by Deaf people. / South Africa

Les travaux présentés dans cette thèse sont dédiés à la conception et l'animation d'entités virtuelles autonomes et réalistes, capables de générer des gestes de la Langue des Signes. L'accent est mis sur la qualité expressive des gestes. Nous montrons que les aspects expressifs du geste, en plus de conférer au mouvement un aspect réaliste, participent à la construction du sens dans le cadre de la visée iconisatrice de la langue des signes. Nous proposons un modèle du discours prenant en compte les visées illustrative et non illustrative de la langue des signes ainsi que ses principales structures de grande iconicité. Ce modèle appelle une spécification des gestes capable de gérer les différentes modes expressifs. Une phase d'analyse nous permet ensuite d'identifier certains paramètres d'expressivité. Cette analyse s'applique sur une séquence de gestes en langue des signes française réalisée par un locuteur sourd selon différentes qualités expressives. Enfin, nous proposons une méthode de génération de mouvement compatible avec le modèle de description des gestes. Cette méthode de génération met en oeuvre différentes méthodes de génération de mouvement dont un modèle de contrôle sensorimoteur capable de s'adapter aux variabilités spatiales et temporelles induites par les paramètres d'expressivité.

Parametric visual effects such as texture generation and shape grammars can be controlled to produce visually perceptible variation. This variation can be rendered on avatars in groupware systems in real time to represent user information in online environments. This type of extra information has been shown to enrich recognition and characterization, but has previously been limited to iconic representations. Modern, highly graphical virtual worlds require more naturalistic and stylistically consistent techniques to represent information.<p> A number of different parametric texture generation techniques are considered and a set of texture characteristics are developed. The variations of these texture characteristics are examined in a study to determine how well users can recognize the visual changes in each. Another study is done to determine how much screen space is required for users to recognize these visual changes in a subset of these texture characteristics.<p> Additionally, an example shape generation system is developed as an example of how shape grammars and L-systems can be used to represent information using a space ship metaphor.<p> These different parametric visual effects are implemented in an example prototype system using space ships. This prototype is a complete functioning groupware application developed in XNA that utilizes many parametric texture and shape effects.

Ce mémoire porte sur l'identité virtuelle qu'est l'avatar. Nous nous intéressons en particulier à l'avatar au sein du métavers Second Life, un univers virtuel tridimensionnel et interactif en temps réel. Second Life est présenté comme un monde où chacun peut vivre une seconde vie. L'usager y crée un avatar, le personnalise, lui attribue une personnalité et une histoire, notamment à travers son apparence. C'est précisément ce processus de construction d'un avatar qui fait l'objet de ce mémoire : comment l'individu construit-il son avatar dans Second Life? Pour répondre à cette question, nous avons mobilisé un cadre théorique constitué de travaux sur les identités virtuelles dans Internet provenant de la sociologie et de la communication, ainsi que de quelques études psychanalytiques. Nous avons effectué une ethnographie en ligne au sein de Second Life pendant une période de six mois, ainsi que des entretiens semi-dirigés avec douze utilisateurs de Second Life. Nos résultats montrent que le processus de construction de l'avatar, notamment sa personnalisation, constitue une occupation centrale dans le métavers. L'avatar est à la fois une projection fantasmée de l'individu et un prolongement de sa personnalité en visant l'expression de son authenticité. La recherche s'accompagne d'un projet créatif, Projections, qui, à des fins d'illustration, témoigne de notre expérience personnelle dans Second Life et de notre relation à l'avatar. ______________________________________________________________________________ MOTS-CLÉS DE L’AUTEUR : Internet, avatar, identité virtuelle, Second Life, métavers.

Parametric visual effects such as texture generation and shape grammars can be controlled to produce visually perceptible variation. This variation can be rendered on avatars in groupware systems in real time to represent user information in online environments. This type of extra information has been shown to enrich recognition and characterization, but has previously been limited to iconic representations. Modern, highly graphical virtual worlds require more naturalistic and stylistically consistent techniques to represent information.<p> A number of different parametric texture generation techniques are considered and a set of texture characteristics are developed. The variations of these texture characteristics are examined in a study to determine how well users can recognize the visual changes in each. Another study is done to determine how much screen space is required for users to recognize these visual changes in a subset of these texture characteristics.<p> Additionally, an example shape generation system is developed as an example of how shape grammars and L-systems can be used to represent information using a space ship metaphor.<p> These different parametric visual effects are implemented in an example prototype system using space ships. This prototype is a complete functioning groupware application developed in XNA that utilizes many parametric texture and shape effects.

Frågan om verkligheten och dess beskaffenhet har länge orsakat stor förbryllning hos människan, vilken historiskt sett har försökt förklarats på olika sätt. Inte minst genom olika slags gudaläror. Idag lever vi helt annorlunda än vad vi gjorde för exempelvis 1000 år sedan. Det är inte längre gudar som är den dominerande verkligheten – det är IT-tekniken. Idag lever alltfler människor i virtuella världar, så kallade Virtual Realities, som en stor del i deras liv. Så vad är verkligheten? Kan en virtuell verklighet vara verklig? Med dessa frågor i bakgrunden, och genom att applicera ett vardagssociologiskt perspektiv på forskningsresultat inom Virtual Reality, prövar denna uppsats synen av vad som är verkligt eller inte. / Projekt Visualisering