This thesis work regards free viewpoint TV. The main idea is that users can switch between multiple streams in order to find views of their own choice. The purpose is to provide fast switching between the streams, so that users experience less delay while view switching. In this thesis work we will discuss different video stream switching methods in detail. Then we will discuss issues related to those stream switching methods, including transmission and switching. We shall also discuss different scenarios for fast stream switching in order to make services more interactive by minimizing delays. Stream switching time varies from live to recorded events. Quality of service (QoS) is another factor to consider which can be improved by assigning priorities to the packets. We will discuss simultaneous stream transmission methods which are based on predictions and reduced quality streams for providing fast switching. We will present prediction algorithm for viewpoint prediction, propose system model for fast viewpoint switching and make evaluation of simultaneous stream transmission methods for free viewpoint TV. Finally, we draw our conclusions and propose future work. / Degree project

Cette étude a des assises autant dans l’histoire de l’art que dans l’esthétique du cinéma. Son point de départ est une aporie : « Qu’est-ce que le mouvement en image dès lors il s’agit de le chercher en dehors des représentations et de leurs techniques ? ». La substance mobile des images dont nous souhaitons faire ici le cas se situe à l’intérieur même du point de vue et non pas à l’enchaînement entre points de vue. Il s’agit de penser sa construction en termes d’un clivage interne, d’une bifurcation. Il s’agit surtout de placer la construction du point de vue au croisement de deux apprentissages [mathésis] : d’un côté celle de la contemplation du monde à partir d’un point fixe, unique ou changeant, de l’autre celle de la mobilité inhérente qui régit tout aspect de la vie. Dans ce contexte, le mouvement des images ne serait pas seulement le résultat d’une révolution du regard ou l’aboutissement d’une aventure technique, mais également et au même titre qu’eux, le résultat d’un événement conflictuel entre deux configurations du [sa]voir différentes bien que totalement pondérées. « Qu’est-ce qui ne marche pas ? » est la question qui nous guide à travers l’écriture. Les images témoignent d’une forme de [dé]marche transversale, d’un accident de la « marche » tant au niveau structurel du film qu’au niveau diégétique. Elles renvoient à quelque chose comme un trouble, un dissentiment. Chaque partie de ce travail constitue, enfin, une étude de cas. Chaque cas dénonce une aporie de point de vue : pittoresque, elliptique, théorique. Les films analysés, très différents les uns des autres, proviennent du cinéma et de ses pratiques élargies. Mais chacune des trois parties est également conçue autour d’un « metteur-en-scène » au sens large : Robert Smithson, Gus van Sant, Victor Burgin. Issus de la grande famille des artistes et non seulement de celle des cinéastes confirmés, ils nous guident à travers la construction de récits ancrés autant dans l’histoire des arts [peinture, sculpture, architecture] que dans les péripéties du cinéma contemporain. / Both art history and cinema aesthetics lie at the foundations of this study. Our starting point is a perplexing difficulty [an aporia]: “What is an image motion when we think about movement beyond its representations and the techniques that accompany them?”. In this dissertation, we examine the mobile substance of images from within the standpoint itself and what resembles to an internal cleavage. We argue that a particular kind of viewpoint can emerge at the crossroads of two different understandings [mathesis]: on the one hand, the contemplation of the world from a single or interchangeable fixed point; on the other hand, the corporeal mobility inherent to every aspect of life. Within this context, image motion is more than just the consequence of a major change in our “ways of looking”, or the outcome of a technical adventure. We argue that image motion is equally the result of a conflict between two different configurations of knowledge - seeing. The images attest to a way of thinking and unthinking motion, illustrated by a disruption in “the walk of the images” which takes place both in the film’s narrative and in the film’s structure revealing something like a trouble, or a dissent. Each section in this work constitutes an autonomous case study. Each case relates to a particular bifurcation of the standpoint: picturesque; elliptical; theoretical. The films in question, very different from one another, stem from cinema and its expanded practices. These three sections are also articulated around three “metteurs-en-scène”: Robert Smithson, Gus Van Sant, Victor Burgin. Belonging to the larger family of artists [and not only to that of confirmed filmmakers], they guide us through the unfolding of a narrative, whose roots are to be found as much in the history of the arts [painting, sculpture, architecture], as in the vicissitudes of contemporary cinema.

Abstract Three-dimensional scene reconstruction has been an important area of research for many decades. It has a myriad of applications ranging from entertainment to medicine. This thesis explores the 3D reconstruction pipeline and proposes novel methods to improve many of the steps necessary to achieve a high quality reconstruction. It proposes novel methods in the areas of depth sensor calibration, simultaneous localization and mapping, depth map inpainting, point cloud simplification, and free-viewpoint rendering. Geometric camera calibration is necessary in every 3D reconstruction pipeline. This thesis focuses on the calibration of depth sensors. It presents a review of sensors models and how they can be calibrated. It then examines the case of the well-known Kinect sensor and proposes a novel calibration method using only planar targets. Reconstructing a scene using only color cameras entails di_erent challenges than when using depth sensors. Moreover, online applications require real-time response and must update the model as new frames are received. The thesis looks at these challenges and presents a novel simultaneous localization and mapping system using only color cameras. It adaptively triangulates points based on the detected baseline while still utilizing non-triangulated features for pose estimation. The thesis addresses the extrapolating missing information in depth maps. It presents three novel methods for depth map inpainting. The first utilizes random sampling to fit planes in the missing regions. The second method utilizes a 2nd-order prior aligned with intensity edges. The third method learns natural filters to apply a Markov random field on a joint intensity and depth prior. This thesis also looks at the issue of reducing the quantity of 3D information to a manageable size. It looks at how to merge depth maps from multiple views without storing redundant information. It presents a method to discard this redundant information while still maintaining the naturally variable resolution. Finally, transparency estimation is examined in the context of free-viewpoint rendering. A procedure to estimate transparency maps for the foreground layers of a multi-view scene is presented. The results obtained reinforce the need for a high accuracy 3D reconstruction pipeline including all the previously presented steps. / Tiivistelmä Kolmiuloitteisen ympäristöä kuvaavan mallin rakentaminen on ollut tärkeä tutkimuksen kohde jo usean vuosikymmenen ajan. Sen sovelluskohteet ulottuvat aina lääketieteestä viihdeteollisuuteen. Väitöskirja tarkastelee 3D ympäristöä kuvaavan mallin tuottamisprosessia ja esittää uusia keinoja parantaa korkealaatuisen rekonstruktion tuottamiseen vaadittavia vaiheita. Työssä esitetään uusia menetelmiä etäisyyssensoreiden kalibrointiin, samanaikaisesti tapahtuvaan paikannukseen ja kartoitukseen, syvyyskartan korjaamiseen, etäisyyspistepilven yksinkertaistamiseen ja vapaan katselukulman kuvantamiseen. Väitöskirjan ensi osa keskittyy etäisyyssensoreiden kalibrointiin. Työ esittelee erilaisia sensorimalleja ja niiden kalibrointia. Yleisen tarkastelun lisäksi keskitytään hyvin tunnetun Kinect-sensorin käyttämiseen, ja ehdotetaan uutta kalibrointitapaa pelkkiä tasokohteita hyväksikäyttäen. Pelkkien värikameroiden käyttäminen näkymän rekonstruointiin tuottaa erilaisia haasteita verrattuna etäisyyssensoreiden käyttöön kuvan muodostamisessa. Lisäksi verkkosovellukset vaativat reaaliaikaista vastetta. Väitös tarkastelee kyseisiä haasteita ja esittää uudenlaisen yhtäaikaisen paikannuksen ja kartoituksen mallin tuottamista pelkkiä värikameroita käyttämällä. Esitetty tapa kolmiomittaa adaptiivisesti pisteitä taustan pohjalta samalla kun hyödynnetään eikolmiomitattuja piirteitä asentotietoihin. Työssä esitellään kolme uudenlaista tapaa syvyyskartan korjaamiseen. Ensimmäinen tapa käyttää satunnaispisteitä tasojen kohdentamiseen puuttuvilla alueilla. Toinen tapa käyttää 2nd-order prior kohdistusta ja intensiteettireunoja. Kolmas tapa oppii filttereitä joita se soveltaa Markov satunnaiskenttiin yhteisillä tiheys ja syvyys ennakoinneilla. Tämä väitös selvittää myös mahdollisuuksia 3D-information määrän pienentämiseen käsiteltävälle tasolle. Työssä selvitetään, kuinka syvyyskarttoja voidaan yhdistää ilman päällekkäisen informaation tallentamista. Työssä esitetään tapa jolla päällekkäisestä datasta voidaan luopua kuitenkin säilyttäen luonnollisesti muuttuva resoluutio. Viimeksi, tutkimuksessa on esitetty läpinäkyvyyskarttojen arviointiproseduuri etualan kerroksien monikatselukulmanäkymissä vapaan katselukulman renderöinnin näkökulmasta. Saadut tulokset vahvistavat tarkan 3D-näkymän rakentamisliukuhihnan tarvetta sisältäen kaikki edellä mainitut vaiheet.

As técnicas de renderização baseadas em imagens permitem que novas visualizações de uma cena sejam geradas a partir de um conjunto de imagens, obtidas a partir de pontos de vista distintos. Pela extensão dessas técnicas para o tratamento de vídeos, podemos permitir a navegação no tempo e no espaço de uma cena obtida a partir de múltiplas câmeras. Nesse trabalho, abordamos o problema de gerar novas visualizações fotorealistas de cenas dinâmicas, com objetos móveis independentes, a partir de vídeos obtidos de múltiplas câmeras com pontos de vista distintos. Os desafios para a solução do problema envolvem a fusão das imagens das múltiplas câmeras minimizando as diferenças de brilho e cor entre elas, a detecção e extração dos objetos móveis da cena e a renderização de novas visualizações combinando um modelo estático da cena com os modelos aproximados dos objetos móveis. Além disso, é importante que novas visualizações possam ser geradas em taxas de quadro interativas de maneira a permitir que um usuário navegue com naturalidade pela cena renderizada. As aplicações dessas técnicas são diversas e incluem aplicações na área de entretenimento, como nas televisões digitais interativas que permitem que o usuário escolha o ponto de vista de filmes ou eventos esportivos, e em simulações para treinamento usando realidade virtual, onde é importante que se haja cenas realistas e reconstruídas a partir de cenas reais. Apresentamos um algoritmo para a calibração das cores capaz de minimizar a diferença de cor e brilho entre as imagens obtidas a partir de câmeras que não tiveram as cores calibradas. Além disso, descrevemos um método para a renderização interativa de novas visualizações de cenas dinâmicas capaz de gerar visualizações com qualidade semelhante à dos vídeos da cena. / Image-based rendering techniques allow the synthesis of novel scene views from a set of images of the scene, acquired from different viewpoints. By extending these techniques to make use of videos, we can allow the navigation in time and space of a scene acquired by multiple cameras. In this work, we tackle the problem of generating novel photorealistic views of dynamic scenes, containing independent moving objects, from videos acquired by multiple cameras with different viewpoints. The challenges presented by the problem include the fusion of images from multiple cameras while minimizing the brightness and color differences between them, the detection and extraction of the moving objects and the rendering of novel views combining a static scene model with approximate models for the moving objects. It is also important to be able to generate novel views in interactive frame rates allowing a user to navigate and interact with the rendered scene. The applications of these techniques are diverse and include applications in the entertainment field, with interactive digital televisions that allow the user to choose the viewpoint while watching movies or sports events, and in virtual-reality training simulations, where it is important to have realistic scenes reconstructed from real scenes. We present a color calibration algorithm for minimizing the color and brightness differences between images acquired from cameras that didn\'t have their colors calibrated. We also describe a method for interactive novel view rendering of dynamic scenes that provides novel views with similar quality to the scene videos.

The theoretical part of the diploma thesis introduces the issue of gradebooks and school information systems. Finally, it describes the selected school information system Bakaláři, which is the subject of research. The research part deals with the view of teachers on online record books in education, on their evaluation and use of the Bachelors system. To collect research data, it was conducted through a questionnaire survey.

Network documentation is often a low-priority task at many companies. Despite this, there are many benefits that should be considered against the fact that it is a comprehensive job. Good network documentation can provide companies the opportunity to reduce dependence on individuals, take proactive decisions and save money. Network documentation mainly consist of physical and/or logical topology descriptions that describes the logical and/or physical layout of the network. These so-called architectural views focus on technology rather than the services and features that the company's network provides. To simplify communication between stakeholders with different areas of knowledge, e.g. between an engineers and corporate management, I propose a model that complement traditional visual description of a network. With the help of viewpoint frameworks such as Kruchten's "4+1" model, I want to visualize relationships between corporate services, business processes, applications and the underlying infrastructure. A qualitative case study at a company with needs of network documentation has resulted in a prototype, a viewpoint framework, based on concepts of enterprise architecture. Analyzing a use case together with the prototype demonstrated that the prototype can visualize relationships between different layers in an organization. The prototype can be used as a starting point or guidance for those who want to document architecture of an enterprise network. The prototype can serve as means of communication in order to justify the investment that in turn ensures a modern energy-efficient operating environment that creates conditions for sustainable information- and communication technology. / Nätverksdokumentation är ofta lågt prioriterat på många företag idag. Men det finns många fördelar som borde vägas mot det faktum att det är ett omfattande jobb. Bra nätverksdokumentation kan ge företag möjligheten att minska personberoende, ta proaktiva beslut och spara pengar. Nätverksdokumentation består huvudsakligen av fysiska och/eller logiska topologidiagram, som beskriver nätverkets utformning. Dessa så kallade vyer fokuserar mer på teknik än de tjänster och funktioner som företagets nätverk tillhandahåller. För att förenkla kommunikation mellan olika intressenter med olika kunskapsbakgrund, t.ex. mellan ingenjörer och ledningen på ett företag, föreslår jag en modell som kompletterar den traditionella visuella beskrivningen av ett nätverk. Med hjälp av ramverk för vyer som t.ex. Kruchtens "4+1" modell, vill jag synliggöra samband mellan företagets tjänster, affärsprocesser, applikationer och den underliggande infrastrukturen. En kvalitativ fallstudie hos ett företag med behov av nätverksdokumentation har resulterat i en prototyp, ett ramverk för vyer, som bygger på koncept inom verksamhetsarkitektur. Analys av ett användarfall med prototypen som underlag demonstrerade att modellen kan synliggöra samband mellan olika skikt i en organisation. Prototypen kan användas som utgångspunkt för den som vill dokumentera arkitekturen hos ett företagsnätverk. Min modell kan fungera som ett kommunikationsmedel för att kunna motivera investeringar i nätverket, som i sin tur säkerställer en modern driftmiljö som skapar förutsättningar för hållbar informations- och kommunikationsteknik.

The aim of the thesis is to create a landscape that supports water retention and helps the river Dyje to create a branched, meandering watercourse. The design also deals with the permeability of the territory and the design of wooden objects that respond in function and shape to the created landscape.

Reconhecimento de objetos é uma aplicação básica da área de processamento de imagens e visão computacional. O procedimento comum do reconhecimento consiste em achar ocorrências de uma imagem modelo numa outra imagem a ser analisada. Consequentemente, se as imagens apresentarem mudanças no ponto de vista da câmera o algoritmo normalmente falha. A invariância a pontos de vista é uma qualidade que permite reconhecer um objeto, mesmo que este apresente distorções resultantes de uma transformação em perspectiva causada pela mudança do ponto de vista. Uma abordagem baseada na simulação de pontos de vista, chamada ASIFT, tem sido recentemente proposta no entorno desta problemática. O ASIFT é invariante a pontos de vista, no entanto falha na presença de padrões repetitivos e baixo contraste. O objetivo de nosso trabalho é utilizar uma variante da técnica de simulação de pontos de vista em combinação com a técnica de extração dos coeficientes de Fourier de projeções radiais e circulares (FORAPRO), para propor um algoritmo invariante a pontos de vista, e robusto a padrões repetitivos e baixo contraste. De maneira geral, a nossa proposta resume-se nas seguintes fases: (a) Distorcemos a imagem, variando os parâmetros de inclinação e rotação da câmera, para gerar alguns modelos e conseguir a invariância a deformações em perspectiva, (b) utilizamos cada como modelo a ser procurado na imagem, para escolher o que melhor case, (c) realizamos o casamento de padrões. As duas últimas fases do processo baseiam-se em características invariantes por rotação, escala, brilho e contraste extraídas pelos coeficientes de Fourier. Nossa proposta, que chamamos AFORAPRO, foi testada com 350 imagens que continham diversidade nos requerimentos, e demonstrou ser invariante a pontos de vista e ter ótimo desempenho na presença de padrões repetitivos e baixo contraste. / Object recognition is a basic application from the domain of image processing and computer vision. The common process recognition consists of finding occurrences of an image query in another image to be analyzed A. Consequently, if the images changes viewpoint in the camera it will normally result in the algorithm failure. The invariance viewpoints are qualities that permit recognition of an object, even if this present distortion resultant of a transformation of perspective is caused by the change in viewpoint. An approach based on viewpoint simulation, called ASIFT, has recently been proposed surrounding this issue. The ASIFT algorithm is invariant viewpoints; however there are flaws in the presence of repetitive patterns and low contrast. The objective of our work is to use a variant of this technique of viewpoint simulating, in combination with the technique of extraction of the Coefficients of Fourier Projections Radials and Circulars (FORAPRO), and to propose an algorithm of invariant viewpoints and robust repetitive patterns and low contrast. In general, our proposal summarizes the following stages: (a) We distort the image, varying the parameters of inclination and rotation of the camera, to produce some models and achieve perspective invariance deformation, (b) use as the model to be search in the image, to choose the that match best, (c) realize the template matching. The two last stages of process are based on invariant features by images rotation, scale, brightness and contrast extracted by Fourier coefficients. Our approach, that we call AFORAPRO, was tested with 350 images that contained diversity in applications, and demonstrated to have invariant viewpoints, and to have excellent performance in the presence of patterns repetitive and low contrast.

Reconhecimento de objetos é uma aplicação básica da área de processamento de imagens e visão computacional. O procedimento comum do reconhecimento consiste em achar ocorrências de uma imagem modelo numa outra imagem a ser analisada. Consequentemente, se as imagens apresentarem mudanças no ponto de vista da câmera o algoritmo normalmente falha. A invariância a pontos de vista é uma qualidade que permite reconhecer um objeto, mesmo que este apresente distorções resultantes de uma transformação em perspectiva causada pela mudança do ponto de vista. Uma abordagem baseada na simulação de pontos de vista, chamada ASIFT, tem sido recentemente proposta no entorno desta problemática. O ASIFT é invariante a pontos de vista, no entanto falha na presença de padrões repetitivos e baixo contraste. O objetivo de nosso trabalho é utilizar uma variante da técnica de simulação de pontos de vista em combinação com a técnica de extração dos coeficientes de Fourier de projeções radiais e circulares (FORAPRO), para propor um algoritmo invariante a pontos de vista, e robusto a padrões repetitivos e baixo contraste. De maneira geral, a nossa proposta resume-se nas seguintes fases: (a) Distorcemos a imagem, variando os parâmetros de inclinação e rotação da câmera, para gerar alguns modelos e conseguir a invariância a deformações em perspectiva, (b) utilizamos cada como modelo a ser procurado na imagem, para escolher o que melhor case, (c) realizamos o casamento de padrões. As duas últimas fases do processo baseiam-se em características invariantes por rotação, escala, brilho e contraste extraídas pelos coeficientes de Fourier. Nossa proposta, que chamamos AFORAPRO, foi testada com 350 imagens que continham diversidade nos requerimentos, e demonstrou ser invariante a pontos de vista e ter ótimo desempenho na presença de padrões repetitivos e baixo contraste. / Object recognition is a basic application from the domain of image processing and computer vision. The common process recognition consists of finding occurrences of an image query in another image to be analyzed A. Consequently, if the images changes viewpoint in the camera it will normally result in the algorithm failure. The invariance viewpoints are qualities that permit recognition of an object, even if this present distortion resultant of a transformation of perspective is caused by the change in viewpoint. An approach based on viewpoint simulation, called ASIFT, has recently been proposed surrounding this issue. The ASIFT algorithm is invariant viewpoints; however there are flaws in the presence of repetitive patterns and low contrast. The objective of our work is to use a variant of this technique of viewpoint simulating, in combination with the technique of extraction of the Coefficients of Fourier Projections Radials and Circulars (FORAPRO), and to propose an algorithm of invariant viewpoints and robust repetitive patterns and low contrast. In general, our proposal summarizes the following stages: (a) We distort the image, varying the parameters of inclination and rotation of the camera, to produce some models and achieve perspective invariance deformation, (b) use as the model to be search in the image, to choose the that match best, (c) realize the template matching. The two last stages of process are based on invariant features by images rotation, scale, brightness and contrast extracted by Fourier coefficients. Our approach, that we call AFORAPRO, was tested with 350 images that contained diversity in applications, and demonstrated to have invariant viewpoints, and to have excellent performance in the presence of patterns repetitive and low contrast.

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