CoordenaÃÃo de AperfeiÃoamento de Pessoal de NÃvel Superior / A dissertaÃÃo analisa o processo de criaÃÃo do sistema de realidade virtual e multimÃdia Visorama, criado em parceria entre a Escola de ComunicaÃÃo da UFRJ e o Instituto de MatemÃtica Pura e Aplicada (IMPA) e coordenado pelos pesquisadores Andrà Parente e Luiz Velho. A pesquisa tem como objeto analisar a dinÃmica passado-presente na concepÃÃo de um sistema panorÃmico imersivo contemporÃneo (Visorama), concebido com base nos sistemas panorÃmicos do sÃculo XIX. Apresenta um histÃrico cronolÃgico, pretensÃes e objetivos da pesquisa e como a questÃo passado-presente foi estabelecida durante todo o processo de produÃÃo do sistema. A anÃlise desse processo toma como base entrevistas realizadas com os pesquisadores coordenadores do projeto e de documentos produzidos entre os anos de 1996 e 2007. à feita uma discussÃo de como as chamadas ânovas tecnologiasâ, em alguns casos, apresentam uma mudanÃa tÃcnica, mas fazem uso de tecnologias ditas âsuperadasâ ou antigas. A questÃo da dinÃmica do tempo à apresentada tambÃm do ponto de vista tecnolÃgico â como procedimentos e problemas de sÃculos passados podem ainda estar presentes em uma produÃÃo contemporÃnea. Por fim, apresentamos os projetos que fizeram uso do sistema e suas relaÃÃes com os espaÃos expositivos.

Thesis (Ph. D.)--Simon Fraser University, 2007. / Senior Supervisor: Jerald Zaslove. Includes bibliographical references (leaves 291-310). Also issued in digital format and available on the World Wide Web.

El uso de los métodos estereoscópicos añade una nueva dimensión a las representaciones y amplía el conocimiento del objeto representado, a la vez que despierta el interés del espectador por aquello que visualiza. Sin embargo, las técnicas estereoscópicas, que tuvieron su origen hace casi dos siglos, son actualmente poco conocidas y apenas se utilizan en el campo científico y docente, pues parece como si sólo estuvieran en manos de los gurús de la industria cinematográfica y sus fundamentos hubieran caído en el olvido, precisamente en un momento en el que las nuevas tecnologías nos abren un mundo de posibilidades. En esta Tesis se pretende aglutinar los aspectos históricos y técnicos de la estereoscopia en un documento único, que pueda servir de ayuda a todos aquellos que quieran incorporarla como una vía complementaria de expresión, tanto en el campo de la divulgación científica, como en el docente. Por este motivo no se aborda sólo una cuestión específica, sino que se pretende ofrecer una visión global del problema estereoscópico y resolver una serie de carencias particulares, detectadas con la práctica de la estereoscopia, realizando aportaciones propias tanto desde el punto de vista técnico, como del histórico. Es importante contextualizar los contenidos, analizando los antecedentes y su historia, empezando por los protagonistas y las aportaciones más relevantes. Resulta igualmente necesario prestar especial atención a los aspectos psicofisiológicos de la visión, que resultan determinantes en el fenómeno de la percepción estereoscópica, teniendo en cuenta los estudios más relevantes en el campo del confort visual. Todo ello permite identificar los parámetros clave de la percepción estereoscópica y los factores que pueden inducir distorsiones perceptivas; a partir de ellos se diseña una metodología de captura estereoscópica propia para establecer los parámetros óptimos, que garanticen una experiencia de visualización confortable y eviten las distorsiones perceptivas del modelo representado. Se analizan también los medios de reproducción y visionado actuales, estudiando los formatos multimedia compatibles con los modernos televisores 3D y las plataformas de distribución de contenido estereoscópico a través de internet. A raíz de este análisis se aporta una metodología eficaz y práctica, basada en software libre, para elaborar y editar material estereoscópico propio, ya sean imágenes estáticas o vídeos. Los panoramas esféricos se han convertido en un recurso muy apreciado en la representación arquitectónica y en las técnicas de realidad virtual, pero nunca antes se había planteado una versión estereoscópica de este tipo de imágenes panorámicas. Por ello, se ha diseñado un método de captura fotográfica que permite obtener panoramas esféricos estereoscópicos y se han desarrollado los algoritmos necesarios para poder elaborar un visor específico con el que visualizarlos de manera efectiva. Se ha realizado una profunda búsqueda bibliográfica y un análisis comparativo de las publicaciones estereoscópicas relacionadas con la expresión gráfica. También se han destacado varios de los escasos ejemplos de aplicación en el campo científico, sacando a la luz algunos casos inéditos. Por último, se ha llevado a cabo un minucioso estudio documental, para tratar de censar y obtener las fotografías estereoscópicas de Valencia, publicadas por los editores comerciales del siglo XIX. Ello permitirá recuperar la memoria de diversos elementos arquitectónicos desaparecidos y conocer los aspectos urbanos de este periodo, en visión estereoscópica. / Cabezos Bernal, PM. (2014). Imágenes estereoscópicas aplicadas a la representación arquitectónica [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/46640 / TESIS / Premios Extraordinarios de tesis doctorales

Tang Wai-Kwan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 88-95). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgement --- p.iii / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Applications --- p.3 / Chapter 1.2 --- Motivation and Goal --- p.6 / Chapter 1.3 --- Thesis Outline --- p.7 / Chapter 2 --- Background and Related Work --- p.8 / Chapter 2.1 --- Panoramic Image Navigation --- p.8 / Chapter 2.2 --- Image Mosaicing --- p.9 / Chapter 2.2.1 --- Image Registration --- p.10 / Chapter 2.2.2 --- Image Composition --- p.12 / Chapter 2.3 --- Immersive Display --- p.13 / Chapter 2.4 --- Video Streaming --- p.14 / Chapter 2.4.1 --- Video Coding --- p.15 / Chapter 2.4.2 --- Transport Protocol --- p.18 / Chapter 3 --- System Design --- p.19 / Chapter 3.1 --- System Architecture --- p.19 / Chapter 3.1.1 --- Video Capture Module --- p.19 / Chapter 3.1.2 --- Video Streaming Module --- p.23 / Chapter 3.1.3 --- Stitching and Rendering Module --- p.24 / Chapter 3.1.4 --- Display Module --- p.24 / Chapter 3.2 --- Design Issues --- p.25 / Chapter 3.2.1 --- Modular Design --- p.25 / Chapter 3.2.2 --- Scalability --- p.26 / Chapter 3.2.3 --- Workload distribution --- p.26 / Chapter 4 --- Panoramic Video Mosaic --- p.28 / Chapter 4.1 --- Video Mosaic to Image Mosaic --- p.28 / Chapter 4.1.1 --- Assumptions --- p.29 / Chapter 4.1.2 --- Processing Pipeline --- p.30 / Chapter 4.2 --- Camera Calibration --- p.33 / Chapter 4.2.1 --- Perspective Projection --- p.33 / Chapter 4.2.2 --- Distortion --- p.36 / Chapter 4.2.3 --- Calibration Procedure --- p.37 / Chapter 4.3 --- Panorama Generation --- p.39 / Chapter 4.3.1 --- Cylindrical and Spherical Panoramas --- p.39 / Chapter 4.3.2 --- Homography --- p.41 / Chapter 4.3.3 --- Homography Computation --- p.42 / Chapter 4.3.4 --- Error Minimization --- p.44 / Chapter 4.3.5 --- Stitching Multiple Images --- p.46 / Chapter 4.3.6 --- Seamless Composition --- p.47 / Chapter 4.4 --- Image Mosaic to Video Mosaic --- p.49 / Chapter 4.4.1 --- Varying Intensity --- p.49 / Chapter 4.4.2 --- Video Frame Management --- p.50 / Chapter 5 --- Immersive Display --- p.52 / Chapter 5.1 --- Human Perception System --- p.52 / Chapter 5.2 --- Creating Virtual Scene --- p.53 / Chapter 5.3 --- VisionStation --- p.54 / Chapter 5.3.1 --- F-Theta Lens --- p.55 / Chapter 5.3.2 --- VisionStation Geometry --- p.56 / Chapter 5.3.3 --- Sweet Spot Relocation and Projection --- p.57 / Chapter 5.3.4 --- Sweet Spot Relocation in Vector Representation --- p.61 / Chapter 6 --- Video Streaming --- p.65 / Chapter 6.1 --- Video Compression --- p.66 / Chapter 6.2 --- Transport Protocol --- p.66 / Chapter 6.3 --- Latency and Jitter Control --- p.67 / Chapter 6.4 --- Synchronization --- p.70 / Chapter 7 --- Implementation and Results --- p.71 / Chapter 7.1 --- Video Capture --- p.71 / Chapter 7.2 --- Video Streaming --- p.73 / Chapter 7.2.1 --- Video Encoding --- p.73 / Chapter 7.2.2 --- Streaming Protocol --- p.75 / Chapter 7.3 --- Implementation Results --- p.76 / Chapter 7.3.1 --- Indoor Scene --- p.76 / Chapter 7.3.2 --- Outdoor Scene --- p.78 / Chapter 7.4 --- Evaluation --- p.78 / Chapter 8 --- Conclusion --- p.83 / Chapter 8.1 --- Summary --- p.83 / Chapter 8.2 --- Future Directions --- p.84 / Chapter A --- Parallax --- p.86

Depth detection is a very common computer vision problem. It shows up primarily in robotics, automation, or 3D visualization domains, as it is essential for converting images to point clouds. One of the poster child applications is self driving cars. Currently, the best methods for depth detection are either very expensive, like LIDAR, or require precise calibration, like stereo cameras. These costs have given rise to attempts to detect depth from a monocular camera (a single camera). While this is possible, it is harder than LIDAR or stereo methods since depth can't be measured from monocular images, it has to be inferred. A good example is covering one eye: you still have some idea how far away things are, but it's not exact. Neural networks are a natural fit for this. Here, we build on previous neural network methods by applying a recent state of the art model to panoramic images in addition to pinhole ones and performing a comparative evaluation. First, we create a simulated depth detection dataset that lends itself to panoramic comparisons and contains pre-made cylindrical and spherical panoramas. We then modify monodepth2 to support cylindrical and cubemap panoramas, incorporating current best practices for depth detection on those panorama types, and evaluate its performance for each type of image using our dataset. We also consider the resources used in training and other qualitative factors.

This thesis analyzes the problem of acquiring stereoscopic images in all gazing directions around a reference viewpoint in space with the purpose of creating stereoscopic panoramas of non-static scenes. The generation of immersive stereoscopic imagery suitable to stimulate human stereopsis requires images from two distinct viewpoints with horizontal parallax in all gazing directions, or to be able to simulate this situation in the generated imagery. The available techniques to produce omnistereoscopic imagery for human viewing are not suitable to capture dynamic scenes stereoscopically. This is a not trivial problem when considering acquiring the entire scene at once while avoiding self-occlusion between multiple cameras. In this thesis, the term omnidirectional refers to all possible gazing directions in azimuth and a limited set of directions in elevation. The acquisition of dynamic scenes restricts the problem to those techniques suitable for collecting in one simultaneous exposure all the necessary visual information to recreate stereoscopic imagery in arbitrary gazing directions. The analysis of the problem starts by defining an omnistereoscopic viewing model for the physical magnitude to be measured by a panoramic image sensor intended to produce stereoscopic imagery for human viewing. Based on this model, a novel acquisition model is proposed, which is suitable to describe the omnistereoscopic techniques based on horizontal stereo. From this acquisition model, an acquisition method based on multiple cameras combined with the rendering by mosaicking of partially overlapped stereoscopic images is identified as a good candidate to produce omnistereoscopic imagery of dynamic scenes. Experimental acquisition and rendering tests were performed for different multiple-camera configurations. Furthermore, a mosaicking criterion between partially overlapped stereoscopic images based on the continuity of the perceived depth and the prediction of the location and magnitude of unwanted vertical disparities in the final stereoscopic panorama are two main contributions of this thesis. In addition, two novel omnistereoscopic acquisition and rendering techniques were introduced. The main contributions to this field are to propose a general model for the acquisition of omnistereoscopic imagery, to devise novel methods to produce omnistereoscopic imagery, and more importantly, to contribute to the awareness of the problem of acquiring dynamic scenes within the scope of omnistereoscopic research.

This thesis analyzes the problem of acquiring stereoscopic images in all gazing directions around a reference viewpoint in space with the purpose of creating stereoscopic panoramas of non-static scenes. The generation of immersive stereoscopic imagery suitable to stimulate human stereopsis requires images from two distinct viewpoints with horizontal parallax in all gazing directions, or to be able to simulate this situation in the generated imagery. The available techniques to produce omnistereoscopic imagery for human viewing are not suitable to capture dynamic scenes stereoscopically. This is a not trivial problem when considering acquiring the entire scene at once while avoiding self-occlusion between multiple cameras. In this thesis, the term omnidirectional refers to all possible gazing directions in azimuth and a limited set of directions in elevation. The acquisition of dynamic scenes restricts the problem to those techniques suitable for collecting in one simultaneous exposure all the necessary visual information to recreate stereoscopic imagery in arbitrary gazing directions. The analysis of the problem starts by defining an omnistereoscopic viewing model for the physical magnitude to be measured by a panoramic image sensor intended to produce stereoscopic imagery for human viewing. Based on this model, a novel acquisition model is proposed, which is suitable to describe the omnistereoscopic techniques based on horizontal stereo. From this acquisition model, an acquisition method based on multiple cameras combined with the rendering by mosaicking of partially overlapped stereoscopic images is identified as a good candidate to produce omnistereoscopic imagery of dynamic scenes. Experimental acquisition and rendering tests were performed for different multiple-camera configurations. Furthermore, a mosaicking criterion between partially overlapped stereoscopic images based on the continuity of the perceived depth and the prediction of the location and magnitude of unwanted vertical disparities in the final stereoscopic panorama are two main contributions of this thesis. In addition, two novel omnistereoscopic acquisition and rendering techniques were introduced. The main contributions to this field are to propose a general model for the acquisition of omnistereoscopic imagery, to devise novel methods to produce omnistereoscopic imagery, and more importantly, to contribute to the awareness of the problem of acquiring dynamic scenes within the scope of omnistereoscopic research.

Le XIXe siècle fut celui de l'apogée de la production mondiale de panoramas : plusieurs furent produits et montrés. Il existe quelques exemples conservés un peu partout dans le monde. Le Cyclorama de Jérusalem fait partie d'un ensemble d'œuvres exécutées sur le thème de la crucifixion, en Europe et en Amérique du Nord. La présente recherche aborde en tout premier lieu, le panorama comme genre dans son univers littéraire et lexical. Le deuxième chapitre trace le portrait de la situation québécoise, pour ce qui est des types de spectacles en place, au moment de l'avènement du panorama. Le troisième chapitre est orienté vers les technologies et leur influence sur les panoramas. Le quatrième chapitre présente les panoramas à thème de crucifixion, produits à partir de 1816 dans le monde. Puis, dans le cinquième chapitre nous avons procédé à l'analyse des problèmes d'attribution du Cyclorama de Jérusalem. / Québec Université Laval, Bibliothèque 2013

[pt] Rendering Baseado em Imagens (IBR - Image-Based Rendering) é um a tendência forte em visualização devido à alta qualidade da imagem. Um dos problemas mais complexos é a composição de objetos (3D ou não) na imagem do panorama. O uso de IBR em plataformas restritas, como os celulares, encontra inúmeras dificuldades e não conta com muitos trabalhos na literatura. Este trabalho analisa as possibilidades de implementação de IBR com objetos ativos em celulares. Um protótipo é proposto e resultados são comentados. / [en] Image Based Rendering (IBR) is a strong tendence in visualization due to the high quality of the images. One of the most complex problems is the 2D/3D object composition in a panorama. The use of IBR in limited platforms, like cell phones, faces a number of problems and the literature is scarse. This work analizes the possibility of implementing IBR with active objects in cell phones. A prototype is presented and results are analyzed.

Este trabalho aborda a utilização de tecnologias para a criação de ambientes virtuais baseados em imagens, com uma aplicação na praça central da cidade de Pelotas/RS. Possibilita que o usuário realize interativamente um passeio no entorno da praça com recursos que permitem avaliações arquitetônicas e urbanísticas por meio de simulações de troca de cor nos prédios, inserção de novas construções e análise do estado de conservação de imóveis, com vantagens sobre métodos tradicionais de análises em montagens fotográficas estáticas. Enfatiza a pesquisa de soluções para visualização interativa de ambientes, focado na identificação de fontes de informação e não na sua modelagem matemática. Para a apresentação do trabalho, além da seleção das cenas urbanas que seriam estudadas, foram consideradas técnicas para a modelagem dos elementos arquitetônicos de forma que se obtivesse a máxima preservação das características naturais (estado de conservação, cores e riqueza de detalhes), formas para a visualização destes dados de maneira integrada com dados bibliográficos (histórico, técnicas construtivas e localização) e também a utilização de objetos multimídia para o enriquecimento na apresentação de conteúdos. Na busca de soluções, foram investigadas as técnicas de modelagem fotogramétrica como forma de obtenção de objetos realísticos com a manutenção das características do objeto original em modelos geométricos simplificados. Foram feitos estudos sobre as formas de apresentação de ambientes virtuais navegáveis através de panoramas interativos e também foi estudada uma forma de aproximar a visualização dos conteúdos com a visão natural humana, através da estereoscopia. O trabalho culmina com a fusão de todas as tecnologias estudadas em uma aplicação denominada “Praça República Virtual – PRV” (para resgatar o antigo nome da atual Praça Coronel Pedro Osório), que funciona como um canteiro de provas na medida que abre um leque de opções para utilização em estudos na área de Arquitetura e Urbanismo. / This work approaches the uses of technologies for creation of virtual environments based on images, with an application to the central square of the city of Pelotas/RS. It makes possible to the user to accomplish an interactive walkthrough with resources that allows architectural and urban planning evaluations through simulations of color changes in the buildings, insertion of new constructions and analysis of the conservation condition of the buildings, with advantages if compared to traditional methods of analysis with static photographic assemblies. It emphasizes the research of solutions for interactive visualization of environments, focused in the identification of sources of information and not in mathematical modeling. Besides the selection of the urban scenes to be studied, it was considered techniques for modeling the architectural elements to obtain the maximal preservation of their natural characteristics (conservation state, colors and wealth of details), ways of visualization of nowadays conservation, but integrated with bibliographical dates (historical, constructive techniques and location). It also includes the uses of multimedia objects to the presentation of contents. In the search of solutions, techniques of photogrammetric modeling were investigated, looking for the construction of realistic objects and maintenance of the characteristics of the original object but using simplified geometric models. It was done a search about forms of presentation of navigable virtual environments through interactive panoramas and also using a prototype of stereoscopy. The work culminates with the coalition of all studied technologies in a prototype of the central square of Pelotas called “Praça República Virtual–PRV” (to rescue the old name of the current Square Cel. Pedro Osório). It works like a stonemason of proofs in the measure that opens various options of use in studies in the area of Architecture and Urban Planning.