<p>Existing VoD solutions often rely on unicast to distribute content, which leads to a higher load on the VoD server as more nodes become interested in the content. In such case, P2P is an alternative way of distributing content since it makes better use of available resources in the network. In this report, several P2P structures are evaluated from an operators point of view. We believe BitTorrent is the most adequate protocol for a P2P solution in IPTV environments. Two BitTorrent clients have been implemented on an IP-STB as proof of concept to find out whether P2P is suited for IPTV environments. Several tests were conducted to evaluate the performance of both clients and to see if they were able to reach a sufficient throughput on the IP-STB. Based upon the tests and the overall impressions, we are convinced that this particular P2P protocol is well suited for IPTV environments. Hopefully, a client developed from scratch for the IP-STB will offer even greater characteristics.</p><p>Further, we have studied how to share recorded content among IP-STBs. Such a design would probably have many similarities to BitTorrent since a central node needs to keep track of content; the IP-STBs take care of the rest.</p><p>The report also brings up whether BitTorrent is suitable for streaming. We believe that the necessary changes required to obtain such functionality will disrupt the strengths of BitTorrent. Some alternative solutions are presented where BitTorrent has been extended with additional modules, such as a server.</p>

<p>TV and radio services have always been distributed over analogue broadcasting networks and been received on a TV -set or a radio receiver. Today this situation is changing due to digitalization and convergence between broadcasting, telecommunications and data communications. Other terminals, such as a PC, can also receive TV and radio services. Digital TV and radio can offer additional services such as e-commerce, electronic program guides and content synchronized to the TV and radio shows. If these services are to be received by several receiving terminals with different properties, the services must be adapted to the terminals. This can be done by scaling the services, meaning that the appearances and functionality of the services vary depending on the terminals’ properties. In this thesis scalable services are examined from a terminal point of view. Present and future receivers, platforms and possible methods to achieve scalability are presented, and their effects on scalable services are discussed.</p> / <p>TV- och radiosändningar har fram till nyligen endast distribuerats över analoga TV- och radionät och tagits emot av traditionella TV- och radioapparater, men detta håller på att ändras i och med att sändningarna digitaliseras och konvergens sker mellan broadcasting, telekom och datakom. Nu kan även andra terminaler fungera som mottagare, t.ex. en PC med ett digital-TVkort eller ett digital-radiokort. Digital TV och radio erbjuder tilläggstjänster som t.ex. ehandel, tjänster kopplade till radio- eller TV-program och elektroniska programguider. Om samma tjänst ska kunna tas emot på flera olika mottagarterminaler med olika egenskaper, måste tjänsten anpassas efter terminalerna. Detta kan göras genom att skala tjänsten, dvs. utseendet och funktionerna varierar beroende på bl.a. terminalens kapacitet. I detta arbete har terminalaspekterna på skalbara tjänster undersökts. Aktuella och framtida terminaler, plattformar och eventuella skalbarhetslösningar presenteras, och deras påverkan på skalbara tjänster diskuteras.</p>

Workshop Mensch-Computer-Vernetzung vom 14.-17. April 2003 in Löbsal (bei Meißen)

Thèse de doctorat : sciences. Informatique : Ecully, Ecole centrale de Lyon : 2005. / 81 réf.

Thèse de doctorat : sciences. Informatique : Ecully, Ecole centrale de Lyon : 2005. / Titre provenant de l'écran-titre. 81 réf.

All digital-TV receivers that are existent on the market today include some sort of a multiplexer which filters the data, the sound and the picture from the digital stream. These de-multiplexers are rather complex and general. The purpose of this Master Thesis is to develop a de-multiplexer which would solely filter one specific type of information out of the data stream, in our case the name of the network. The main task of this project contains a close study of MPEG2 and the transport streams in order to find a solution and create a static de-multiplexer. Another part of this project is to choose an adequate method for the control and data communication. We will study the bus protocols I2C and SPI. Finally we will construct the entire circuit after having chosen the Development Environment, DE and considered all the different circuit designs suitable for our task as well as the working at a low production cost, which is of course an important factor and challenge. The first part of construction will be made in Very High Speed Integrated Circuit Hardware Description Language, VHDL, code and once the program is tested and working we will implement it and create the circuit. We will run a test of the final circuit test by filtering a near satellite signal and the get the name of the aimed network.

Développer un système de rendu distant pour terminaux légers et mobiles traitant d'objets multimédias et de leur sémantique consiste à (1) offrir une véritable expérience multimédia collaborative au niveau du terminal, (2) assurer la compatibilité avec les contraintes liées au réseau (bande passante, erreurs et latence variables en temps) et au terminal (ressources de calcul et de mémoire réduites) et (3) s'affranchir des types de terminaux et des spécificités des communautés.Cette thèse traite de ces enjeux et se positionne en rupture avec l'état de l'art en développant une architecture support fondée sur la gestion sémantique du contenu multimédia. Le principe consiste à convertir en temps réel le contenu graphique généré par l'application en un graphe de scène multimédia et à le gérer en fonction de la sémantique de ses composantes.L'optimisation de la bande passante est assurée par la compression adaptative du graphe de scène et par la compression sans perte des messages de collaboration. Les deux méthodes développées sont caractérisées respectivement par la création d'un unique graphe de scène intrinsèquement adaptable au réseau/terminal et par la mise à jour dynamique du dictionnaire de codage en fonction des messages générés par les utilisateurs. Elles sont brevetées.Les fonctionnalités collaboratives interviennent directement au niveau du contenu grâce à l'enrichissement du graphe de scène par un nouveau type de nœud, dont la normalisation ISO est en cours.Le démonstrateur logiciel sous-jacent, dénommé MASC (Multimedia Adaptive Semantic Collaboration), permet de comparer objectivement cette nouvelle architecture aux solutions actuellement déployées par des acteurs majeurs du domaine (VNC RBF ou Microsoft RDP). Deux types d'application ont été considérés : l'édition du texte et la navigation sur Internet. Les évaluations quantitatives montrent: (1) un impact limité des artéfacts visuels de conversion (PSNR compris entre 30 et 42 dB et SSIM supérieur à 0,9999), (2) consommation de la bande passante downlink (resp. uplink) réduite d'un facteur de 2 à 60 (resp. de 3 à 10), (3) latence dans la transmission des événements générés par l'utilisateur réduite d'un facteur de 4 à 6, (4) consommation des ressources de calcul côté client réduite d'un facteur 1,5 par rapport à VNC RFB.

No description available.

No description available.

Nowadays the World Wide Web increasingly provides rich multimedia contents to its users.In order to further enhance the experience of web-users, researchers have sought solutions to integrate yet another modality into the web experience by augmenting web content with haptic properties. In those applications, users are able to interact with web virtual environments (such as games and e-learning systems) enriched with haptic contents. However, it is not easy for designers without pro cient web programming background and basic knowledge regarding haptics, to develop a web application with haptic content enabled. Additionally, there is currently no standard to describe and reuse a well-described haptic application which can be played in web browsers. In this thesis, I present an MPEG-V based authoring tool for facilitating the development procedure of haptics-enabled web applications. The system provides an interface for users to create their own application, add custom 3D models, and modify their graphic and haptic properties. Haptic properties include the speci cation of collision detection mechanism and object surface properties which in turn directly a ect the force simulations. Finally, the user is able to export a haptic-enabled 3D scene in a standard MPEG-V format which can be reconstructed in a web haptic player. A detailed experiment is conducted to evaluate the force simulations, application development process and design of user interface. The results not only verify my proposed methodology, but also show the high acceptance level by users with all levels of programming knowledge of the system.