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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Automação do processo de corte e dobra de armaduras para estruturas de concreto integrada ao processo BIM. / Automation of the cutting and bending process of reinforcing bars for concrete structures integrated to the BIM process.

Maciel, Alex Roda 29 May 2018 (has links)
A consolidação do processo de Modelagem da Informação da Construção (BIM) tende a contribuir para o aumento da eficiência da indústria da construção civil, fomentando novos fluxos de trabalho e permitindo o reuso de informações ao longo do ciclo de vida dos empreendimentos. Apesar do potencial de integração e automação associados ao processo BIM, o uso das informações digitais contidas no modelo para facilitar a pré-fabricação de produtos para a construção mostra-se incipiente. Nota-se que emprego da fabricação digital encontra obstáculos sobretudo em setores que atuam de modo segregado, e que por isto mesmo demandam sinergia, bem como o uso de normas e padrões que possibilitem a interoperabilidade e reuso das informações geradas nas fases anteriores a fabricação. Neste contexto, foi feita uma análise do uso da fabricação digital aplicada ao processamento industrial de aço para estruturas de concreto armado (corte e dobra). Embora os fabricantes que atuam neste setor possuam suporte a interface digital com os demais agentes, a configuração de sua cadeia de produtiva, bem como os processos tradicionalmente adotados, promovem a ocorrência de ilhas de automação ligadas por transferência manual e reentrada de dados. Como forma de reduzir a intervenção manual para a transcrição dos dados, propõe-se o uso do esquema de dados Industry Foundation Classes (IFC) na fabricação digital de componentes de armadura. Este trabalho tem por objetivo apresentar uma solução técnica, baseada no esquema IFC, aos requisitos de troca de informação necessários no fluxo de trabalho proposto. Com base nos requisitos de troca identificados por meio do método Information Delivery Manual (IDM), apresenta-se como essas informações podem ser mapeadas e qual o subconjunto de dados necessários à fabricação digital baseada no esquema IFC4. Por fim, apresenta-se a documentação e validação da solução técnica desenvolvida de acordo com o método Model View Definition (MVD) e com o uso da ferramenta ifcDoc. Após a realização de testes com base no esquema IFC4 foi constatada a viabilidade para recuperação dos dados contidos no modelo. Entretanto também foi identificada a carência de ferramentas comerciais que suportem tal funcionalidade. / The consolidation of Building Information Modeling (BIM) possibly contributes to the increase of the efficiency in the construction industry, by fostering new workflows and data reuse throughout projects life cycle. Despite the potential for integration and automation associated with BIM, the use of the digital information contained in the model to facilitate prefabrication of construction products is still incipient. The digital fabrication finds obstacles in sectors that act in a segregated manner, henceforth needs standard adoption to allow reuse of the information generated in the phases prior to production. In this context, it was analyzed the use of digital fabrication applied to the industrial processing of reinforcement bars for concrete structures (rebar cutting and bending). Although the fabricators who act in this sector already have support to the digital interface with other agents, the supply chain configuration adopted by the Brazilian market, as well as the traditional paper-based processes employed, promote the occurrence of \"islands of automation\" connected by manual data transfer. In order to reduce the need for manual intervention for data re-interpretation and re-entry, it is proposed to use the Industry Foundation Classes (IFC) data schema to promote the digital interface between the reinforcing bar supply chain stakeholder\'s. This work aims to present an IFC-based technical solution to the fabricator\'s information requirements by means of the Information Delivery Manual (IDM) and Model View Definition (MVD) standards. On the basis of the exchange requirements specified by rebar fabricator through IDM method, it is presented the IFC schema subset entailed and how this information can be mapped in order to allow the use of IFC on the cut & bend rebar supply chain. Finally, the technical solution was documented in an MVD and validate with the ifcDoc tool. After conducting validation tests based on the IFC4 schema, it was verified the viability to recover the data contained in the model. However, the lack of commercial tools that support such functionality has also been identified.
2

Un environnement méthodologique et logiciel pour l'interopérabilité de la maquette numérique du bâtiment et de la simulation énergétique : application à la réglementation thermique RT2012. / A methodological and software environment for the interoperability between Building Information Models and energy simulation : application to the French Thermal Regulation RT 2012

El Asmi, Emira 13 April 2016 (has links)
L’analyse de la performance énergétique des bâtiments neufs repose massivement sur des outils logiciels de simulation. La valeur ajoutée de ces derniers est indéniable : ils permettent d’optimiser la conception en facilitant l’évaluation des performances énergétiques du bâtiment durant la phase de conception. Leur impact est cependant limité par plusieurs obstacles, dont les principaux sont le niveau d’expertise requis pour leur utilisation et l’absence de connexion aux outils de Conception Assistée par Ordinateur (CAO). Ce dernier point devient particulièrement critique au moment où l’utilisation de la maquette numérique BIM (Building Information Model) se généralise et où les modèles issus d’outils de CAO sont de plus en plus riches.Cette thèse repose sur cette observation et propose, afin de profiter pleinement du potentiel du BIM et des outils en lien, de contribuer à l’émergence d’approches permettant une transformation fiable et transparente des informations du bâtiment numérique BIM vers les fichiers d'entrée des environnements de simulation. Cela se traduirait par des avantages significatifs, tant sur le rapport coût-efficacité (l’analyse est effectuée plus efficacement), qu’au niveau de la fiabilité (les modèles de simulation sont conformes aux modèles de conception). Toutefois, pour mettre en œuvre de telles approches, plusieurs obstacles doivent être pris en compte : le premier est la nécessité de disposer d’un langage normalisé commun pour le BIM, le deuxième est la définition de mécanismes méthodologiques efficaces et normalisés afin d’enrichir le BIM pour la simulation, le troisième est la mise à disposition d'outils logiciels fiables pour la transformation automatisée du BIM vers les modèles de simulation thermique.Le premier obstacle est en passe d’être levé grâce aux standards issus du consortium international buildingSMART, en particulier les « Industry Foundation Classes » (IFC) qui sont désormais largement reconnus comme un format d'échange standard du BIM dans le domaine de la construction. Le deuxième verrou reste actuel : l’IFC, même dans sa dernière version IFC4, laisse entier de nombreux problèmes de formulation de concepts propres aux domaines métiers, en particulier celui de la simulation énergétique. Cependant, des environnements méthodologiques ont vu le jour permettant d’étendre et d’enrichir de façon structurée les formats de données BIM. C’est par exemple le cas de l’IDM (Information Delivery Manual) et du MVD (Model View Définition) de buildingSMART, pour les IFC.L’objectif de nos travaux est triple. En premier lieu, il s’agit de mettre en œuvre et évaluer l’environnement IDM/ MVD de buildingSMART pour l’interconnexion entre le BIM (format IFC) et la simulation énergétique. Cette étude nous a amenés à proposer un modèle pivot (BSM pour « Building Simulation Model ») basé sur une analogie avec les approches prônées par l’ingénierie dirigée par les modèles. Nous avons également développé un outil logiciel, qui inclut une base de règles de mapping, afin d’automatiser la traduction de l’information entre le modèle IFC et le modèle de simulation. Cette approche a été évaluée sur la base de l’outil COMETH (moteur de simulation de la régulation thermique française RT2012) mais elle est généralisable. / Energy performance analysis of new buildings strongly relies on simulation tools. They optimize the design by facilitating building performance analysis during the design phase. However, there are several limitations, among which one of the main is the lack of reliable connections between Computer Aided Design (CAD) and simulation tools. This is particularly critical at a time when the concept of Building Information Model (BIM) is widely applied and the CAD models are becoming richer.This thesis proposes to take advantage of the potential of BIM in order to contribute to emerging approaches for a reliable and seamless interconnection between building information models and simulation environment input files. This would result into significant benefits, both from the cost-effectiveness (analysis is performed more effectively) and the reliability (simulation models strictly comply with design models) points of view. However, to implement such approaches, several barriers have to be considered. The first is the need for a common, standardized BIM language. The second is the definition of adequate and standardized extension mechanisms, to customize BIM for simulation-specific purposes. The third is the provision of software tools, for effective and reliable BIM to simulation models transformation.The first barrier is likely to be overcome through the advent of the buildingSMART Industry Foundation Classes (IFC), which is widely recognized as a standard BIM exchange format in the construction industry. However, with respect to the second barrier, the IFC remains a wide-purpose modelling language and as such, fails to address many domain-specific issues, like e.g. energy simulation. This limitation has been acknowledged by buildingSMART, who have delivered novel methodological tools to allow for domain-specific customization of IFC. The main one is called the Information Delivery Manual (IDM). The aim of our work is the implementation and evaluation the BuildingSMART framework IDM/MVD to interconnect BIM (IFC) and energy simulation. This study led us to propose a pivotal model (BSM for « Building Simulation Model») based on an analogy with model driven engineering approaches. We also have developed a software prototype, which includes a set of mapping rules that automates the translation process between the IFC model and the simulation tool. In the scope of this study, we targeted the COMETH simulation tool (a simulation engine based on the French thermal regulation RT2012) but our results can easily be extended to additional tools.
3

Edge-aided virtual view rendering for multiview video plus depth

Muddala, Suryanarayana Murthy, Sjöström, Mårten, Olsson, Roger, Tourancheau, Sylvain January 2013 (has links)
Depth-Image-Based Rendering (DIBR) of virtual views is a fundamental method in three dimensional 3-D video applications to produce dierent perspectives from texture and depth information, in particular the multi-viewplus-depth (MVD) format. Artifacts are still present in virtual views as a consequence of imperfect rendering using existing DIBR methods. In this paper, we propose an alternative DIBR method for MVD. In the proposed method we introduce an edge pixel and interpolate pixel values in the virtual view using the actual projected coordinates from two adjacent views, by which cracks and disocclusions are automatically lled. In particular, we propose a method to merge pixel information from two adjacent views in the virtual view before the interpolation; we apply a weighted averaging of projected pixels within the range of one pixel in the virtual view. We compared virtual view images rendered by the proposed method to the corresponding view images rendered by state-of-theart methods. Objective metrics demonstrated an advantage of the proposed method for most investigated media contents. Subjective test results showed preference to dierent methods depending on media content, and the test could not demonstrate a signicant dierence between the proposed method and state-of-the-art methods.
4

Automação do processo de corte e dobra de armaduras para estruturas de concreto integrada ao processo BIM. / Automation of the cutting and bending process of reinforcing bars for concrete structures integrated to the BIM process.

Alex Roda Maciel 29 May 2018 (has links)
A consolidação do processo de Modelagem da Informação da Construção (BIM) tende a contribuir para o aumento da eficiência da indústria da construção civil, fomentando novos fluxos de trabalho e permitindo o reuso de informações ao longo do ciclo de vida dos empreendimentos. Apesar do potencial de integração e automação associados ao processo BIM, o uso das informações digitais contidas no modelo para facilitar a pré-fabricação de produtos para a construção mostra-se incipiente. Nota-se que emprego da fabricação digital encontra obstáculos sobretudo em setores que atuam de modo segregado, e que por isto mesmo demandam sinergia, bem como o uso de normas e padrões que possibilitem a interoperabilidade e reuso das informações geradas nas fases anteriores a fabricação. Neste contexto, foi feita uma análise do uso da fabricação digital aplicada ao processamento industrial de aço para estruturas de concreto armado (corte e dobra). Embora os fabricantes que atuam neste setor possuam suporte a interface digital com os demais agentes, a configuração de sua cadeia de produtiva, bem como os processos tradicionalmente adotados, promovem a ocorrência de ilhas de automação ligadas por transferência manual e reentrada de dados. Como forma de reduzir a intervenção manual para a transcrição dos dados, propõe-se o uso do esquema de dados Industry Foundation Classes (IFC) na fabricação digital de componentes de armadura. Este trabalho tem por objetivo apresentar uma solução técnica, baseada no esquema IFC, aos requisitos de troca de informação necessários no fluxo de trabalho proposto. Com base nos requisitos de troca identificados por meio do método Information Delivery Manual (IDM), apresenta-se como essas informações podem ser mapeadas e qual o subconjunto de dados necessários à fabricação digital baseada no esquema IFC4. Por fim, apresenta-se a documentação e validação da solução técnica desenvolvida de acordo com o método Model View Definition (MVD) e com o uso da ferramenta ifcDoc. Após a realização de testes com base no esquema IFC4 foi constatada a viabilidade para recuperação dos dados contidos no modelo. Entretanto também foi identificada a carência de ferramentas comerciais que suportem tal funcionalidade. / The consolidation of Building Information Modeling (BIM) possibly contributes to the increase of the efficiency in the construction industry, by fostering new workflows and data reuse throughout projects life cycle. Despite the potential for integration and automation associated with BIM, the use of the digital information contained in the model to facilitate prefabrication of construction products is still incipient. The digital fabrication finds obstacles in sectors that act in a segregated manner, henceforth needs standard adoption to allow reuse of the information generated in the phases prior to production. In this context, it was analyzed the use of digital fabrication applied to the industrial processing of reinforcement bars for concrete structures (rebar cutting and bending). Although the fabricators who act in this sector already have support to the digital interface with other agents, the supply chain configuration adopted by the Brazilian market, as well as the traditional paper-based processes employed, promote the occurrence of \"islands of automation\" connected by manual data transfer. In order to reduce the need for manual intervention for data re-interpretation and re-entry, it is proposed to use the Industry Foundation Classes (IFC) data schema to promote the digital interface between the reinforcing bar supply chain stakeholder\'s. This work aims to present an IFC-based technical solution to the fabricator\'s information requirements by means of the Information Delivery Manual (IDM) and Model View Definition (MVD) standards. On the basis of the exchange requirements specified by rebar fabricator through IDM method, it is presented the IFC schema subset entailed and how this information can be mapped in order to allow the use of IFC on the cut & bend rebar supply chain. Finally, the technical solution was documented in an MVD and validate with the ifcDoc tool. After conducting validation tests based on the IFC4 schema, it was verified the viability to recover the data contained in the model. However, the lack of commercial tools that support such functionality has also been identified.
5

Rule logic and its validation framework of model view definitions for building information modeling

Lee, Yong Cheol 07 January 2016 (has links)
With the growing number of complex requirements for building and facility projects, diverse domain experts iteratively exchange building design and product data during the design, construction, and facility management phases. Such data exchanges, however, frequently involve unintended geometric transformations, inaccurate project requirements, and insufficient syntactic and semantic elements in building model data. To ensure the interoperability of building information models, this dissertation includes an examination of rules categorized from the Precast Concrete Institute model views and a generalization of the rule logic and structures of each rule set. Moreover, rule logic is coded and implemented on modularized validation platforms of a validation tool referred to as the IfcDoc tool, an automated model view documentation and validation application. This dissertation is expected to help domain experts evaluate whether building design data fulfill the data exchange specifications of their domain and the objectives of a proposed project. Furthermore, to identify unreliable and inconsistent IFC mapping procedures of BIM authoring tools, software developers using the proposed approach would implement an automated debugging process in their IFC interfaces according to the specifications of a targeted model view.
6

Formal specification of industry foundation class concepts using engineering ontologies

Venugopal, Manu 14 November 2011 (has links)
Architecture, Engineering, Construction (AEC) and Facilities Management (FM) involve domains that require a very diverse set of information and model exchanges to fully realize the potential of Building Information Modeling (BIM). Industry Foundation Classes (IFC) provides a neutral and open schema for interoperability. Model View Definitions (MVD) provide a common subset for specifying the exchanges using IFC, but are expensive to build, test and maintain. A semantic analysis of IFC data schema illustrates the complexities of embedding semantics in model views. A software engineering methodology based on formal specification of shared resources, reusable components and standards that are applicable to the AEC-FM industry for development of a Semantic Exchange Module (SEM) structure for IFC schema is adopted for this research. This SEM structure is based on engineering ontologies that are capable of developing more consistent MVDs. In this regard, Ontology is considered as a machine-readable set of definitions that create a taxonomy of classes and subclasses, and relationships between them. Typically, the ontology contains the hierarchical description of important entities that are used in IFC, along with their properties and business rules. This model of an ontological framework, similar to that of Semantic Web, makes the IFC more formal and consistent as it is capable of providing precise definition of terms and vocabulary. The outcome of this research, a formal classification structure for IFC implementations for the domain of Precast/ Prestressed Concrete Industry, when implemented by software developers, provides the mechanism for applications such as modular MVDs, smart and complex querying of product models, and transaction based services, based on the idea of testable and reusable SEMs. It can be extended and also helps in consistent implementation of rule languages across different domains within AEC-FM, making data sharing across applications simpler with limited rework. This research is expected to impact the overall interoperability of applications in the BIM realm.
7

Modelling and Optimization of Conventional and Unconventional Batch Reactive Distillation Processes. Investigation of Different Types Batch Reactive Distillation Columns for the Production of a Number of Esters such as Methyl Lactate, Methyl Decanoate, Ethyl Benzoate, and Benzyl Acetate using gPROMS

Aqar, Dhia Y. January 2018 (has links)
The synthesis of a number of alkyl esters such as methyl lactate, methyl decanoate, and ethyl benzoate via esterification in a reactive distillation is quite challenging. It is due to the complexity in the thermodynamic behaviour of the chemical species in the reaction mixture in addition to the difficulty of keeping the reactants together in the reaction section. One of the reactants (in these esterification reactions) having the lowest boiling point can separate from the other reactant as the distillation continues. This can result in a significant drop in the reaction conversion in a conventional reactive distillation whether it is a batch or a continuous column. To overcome this challenge, new different types of batch reactive distillation column configurations: (1) integrated conventional (2) semi-batch (3) integrated semi-batch (4) integrated dividing-wall batch distillation columns have been proposed here. Four esterification reaction schemes such as (a) esterification of lactic acid (b) esterification of decanoic acid (c) esterification of benzoic acid (d) esterification of acetic acid are investigated here. A detailed dynamic model based on mass, energy balances, chemical reaction, and rigorous thermodynamic (chemical and physical) properties is considered and incorporated in the optimisation framework within gPROMS (general PROcess Modelling System) software. It is found that for the methyl lactate system, the i-SBD operation outperforms the classical batch operations (CBD or SBD columns) to satisfy the product constraints. While, for the methyl decanoate system, the i-DWCBD operation outperforms all CBD, DWBD and sr-DWBD configurations by achieving the higher reaction conversion and the maximum product purity. For the ethyl benzoate system, the performance of i-CBD column is superior to the CBD process in terms of product quality, and conversion rate of acid. The CBD process is found to be a more attractive in terms of operating time saving, and annual profit improvement compared to the IBD, and MVD processes for the benzyl acetate system. / The Higher Committee for Education Development in Iraq (HCED)
8

Tecnologia BIM na arquitetura

Maria, Mônica Mendonça 04 February 2009 (has links)
Made available in DSpace on 2016-04-18T12:12:29Z (GMT). No. of bitstreams: 4 Monica Mendonca Maria1.pdf: 763444 bytes, checksum: d5fe5f8d60e9e7bd08aecfc0a88b8198 (MD5) Monica Mendonca Maria2.pdf: 1212194 bytes, checksum: b5f0b63d350777866e3955220d604827 (MD5) Monica Mendonca Maria3.pdf: 1656626 bytes, checksum: c2a9d642d2e4d86b7409ce54aabebe89 (MD5) Monica Mendonca Maria4.pdf: 2215429 bytes, checksum: 64893a7cd54a8d0497c2dc13776f74e4 (MD5) Previous issue date: 2009-02-04 / This dissertation presents the technology within BIM and its implication in the architectural and engineering design process. Since the 60 s, aerospace and automotive industries have already revolutionized the way of project with the CAD, and manufacture with the assembly lines. In AEC, the CAD became BIM, a new way of project, build and manage, from conception till life cycle building. This brought a project and construction time reduction, cost and environmental impacts decrease foreseen in LEED and merged in BIM. / Este trabalho objetiva apresentar a tecnologia contida no BIM e suas implicações no processo de projeto da arquitetura e engenharia civil. A partir de 1960, as indústrias, aeronáutica e automotiva, já haviam revolucionado a forma de projetar com o CAD, e de fabricar com as linhas de montagem. Na Arquitetura, Engenharia e Construção, o CAD está evoluindo para o BIM (Building Information Modeling), uma forma de projetar, construir e gerenciar, da concepção ao habite-se, aplicável a todo o ciclo de vida da edificação. Dessa forma houve não só uma redução no tempo de projeto e construção, mas também em custos e impactos ambientais previstos em normas internacionais incorporadas ao BIM.
9

Thérapie cellulaire de l’angiogenèse tumorale : évaluation par imagerie morphologique et fonctionnelle en IRM et vidéomicroscopie de fluorescence / Cellular therapy of tumor angiogenesis : morphological and functional imaging using MRI and videomicroscopy

Faye, Nathalie 07 December 2011 (has links)
Introduction : L’angiogenèse tumorale conduit au développement de nouveaux vaisseaux destinés à permettre la croissance de la tumeur. Les vaisseaux tumoraux sont caractérisés notamment par des anomalies des cellules murales (cellules musculaires périvasculaires), responsables d’anomalies de la fonctionnalité et de la maturation. Dans ce travail de thèse, nous avons étudié un modèle tumoral de thérapie cellulaire par injection de cellules murales en IRM et vidéomicroscopie de fluorescence. Matériels et méthodes : Notre étude a porté sur un modèle sous cutané de carcinome épidermoïde chez la souris nude. Les animaux étaient divisés en trois groupes : contrôle (n=17), contrôle négatif (n=16) et « traité » avec injection locale de cellules murales humaines (n=17). Les animaux bénéficiaient d’une IRM et d’une exploration par vidéomicroscopie avant (J7) et après traitement (J14). Les paramètres mesurés étaient la taille tumorale (pied-à-coulisse et IRM), la densité microvasculaire (DMV par IRM, vidéomicroscopie et histologie), l’ADC, f, Dr et D* (IRM de diffusion), les variations de R2* sous air, oxygène et carbogène (IRM par effet BOLD) et « l’index leakage » (reflétant la perméabilité capillaire, en vidéomicroscopie). Résultats : Lors de la croissance tumorale, le groupe contrôle a montré une diminution des vaisseaux circulants (ou fonctionnels) qui se reflétait par une diminution du D* et du R2* sous air, une perte de la capacité à répondre au carbogène qui se reflétait par une augmentation du delta R2* sous carbogène, et une augmentation de la perméabilité capillaire qui se traduisait par un « index leakage » plus élevé. Dans le groupe traité par injection de cellules murales, nous avons observé un ralentissement de la croissance tumorale et une stabilisation de ces paramètres de microcirculation et maturation vasculaire. Conclusion : Nous avons montré un effet biologique de notre thérapie cellulaire par injection locale de cellules murales qui se traduisait par un ralentissement de la croissance tumorale, une stabilisation de l’hémodynamique microcirculatoire et de la maturation, et une perméabilité capillaire diminuée, concordants avec l’effet présumé stabilisateur et normalisateur des cellules murales sur les microvaisseaux. / Introduction : Tumor angiogenesis leads to the development of new vessels enabling the growth of the tumor. Tumor vessels are characterized by abnormalities including mural cells (perivascular muscular cells) responsible for abnormal vessel function and maturation. In this thesis, we studied cellular therapy in a tumor model by injection of mural cells using MRI and fluorescence videomicroscopy. Materiels and methods: Nude mice were injected with squamous cell TC1 tumors and animals were divided in three groups: control (n=17), sham control (n=16) and treated by local injection of human mural cells (n=17). Animals underwent MRI and videomicroscopy before (D7) and after (D14) treatment. Measured parameters included tumor size (caliper and MRI), microvessels density (MVD using MRI, videomicroscopy and pathology), ADC, f, Dr, D* (diffusion MRI), R2* variations under air, oxygen and carbogen (BOLD MRI), and ‘index leakage’ (reflecting capillary permeability, using videomicroscopy). Results: During tumor growth, the control group showed a decrease in circulating (or functional) vessels reflected by a decrease in D* and R2* under air, the loss of vessel ability to respond to carbogen reflected by an increase of the delta R2* under carbogen, and increased capillary permeability resulting in a higher ”index leakage”. In the group treated by injection of mural cells, we observed a slowing of tumor growth and stabilization of these parameters of microcirculation and vessel maturation. Conclusion : Therapy by local injection of mural cells was effective resulting in slower tumor growth, stabilization of microcirculatory hemodynamics and maturation, and decreased capillary permeability, consistent with the alleged ‘stabilizing’ and ‘normalizing’ effects of mural cells on microvessels.
10

Compression des données Multi-View-plus-Depth (MVD): de l'analyse de la qualité perçue à l'élaboration d'outils pour le codage des données MVD

Bosc, Emilie 22 October 2012 (has links) (PDF)
Cette thèse aborde la problématique de compression des vidéos multi-vues avec pour pilier un souci constant du respect de la perception humaine du media, dans le contexte de la vidéo 3D. Les études et les choix portés durant cette thèse se veulent orientés par la recherche de la meilleure qualité perçue possible des vues synthétisées. L'enjeu des travaux que de cette thèse réside dans l'investigation de nouvelles techniques de compression des données multi-view-plus-depth (MVD) limitant autant que possible les dégradations perceptibles sur les vues synthétisées à partir de ces données décodées. La difficulté vient du fait que les sources de dégradations des vues synthétisées sont d'une part multiples et d'autre part difficilement mesurables par les techniques actuelles d'évaluation de qualité d'images. Pour cette raison, les travaux de cette thèse s'articulent autour de deux axes principaux: l'évaluation de la qualité des vues synthétisées ainsi que les artefacts spécifiques et l'étude de schémas de compression des données MVD aidée de critères perceptuels. Durant cette thèse nous avons réalisé des études pour caractériser les artefacts liés aux algorithmes DIBR. Les analyses des tests de Student réalisés à partir des scores des tests de Comparaisons par paires et ACR-HR ont permis de déterminer l'adéquation des méthodes d'évaluation subjective de qualité pour le cas des vues synthétisées. L'évaluation des métriques objectives de qualité d'image/vidéo ont également permis d'établir leur corrélation avec les scores subjectifs. Nous nous sommes ensuite concentrés sur la compression des cartes de profondeur, en proposant deux méthodes dérivées pour le codage des cartes de profondeur et basées sur la méthode LAR. En nous appuyant sur nos observations, nous avons proposé une stratégie de représentation et de codage adaptée au besoin de préserver les discontinuités de la carte tout en réalisant des taux de compression importants. Les comparaisons avec les codecs de l'état de l'art (H.264/AVC, HEVC) montrent que notre méthode propose des images de meilleure qualité visuelle à bas débit. Nous avons également réalisé des études sur la répartition du débit entre la texture et la profondeur lors de la compression de séquences MVD. Les résultats de cette thèse peuvent être utilisés pour aider à la conception de nouveaux protocoles d'évaluation de qualité de données de synthèse; pour la conception de nouvelles métriques de qualité; pour améliorer les schémas de codage pour les données MVD, notamment grâce aux approches originales proposées; pour optimiser les schémas de codage de données MVD, à partir de nos études sur les relations entre la texture et la profondeur.

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