Diseño centrado en calidad para la difusión Peer-to-Peer de video en vivo

El uso de redes Peer-to-Peer (P2P) es una forma escalable para ofrecer servicios de video sobre Internet. Este documento hace foco en la definición, desarrollo y evaluación de una arquitectura P2P para distribuir video en vivo. El diseño global de la red es guiado por la calidad de experiencia (Quality of Experience - QoE), cuyo principal componente en este caso es la calidad del video percibida por los usuarios finales, en lugar del tradicional diseño basado en la calidad de servicio (Quality of Service - QoE) de la mayoría de los sistemas. Para medir la calidad percibida del video, en tiempo real y automáticamente, extendimos la recientemente propuesta metodología Pseudo-Subjective Quality Assessment (PSQA). Dos grandes líneas de investigación son desarrolladas. Primero, proponemos una técnica de distribución de video desde múltiples fuentes con las características de poder ser optimizada para maximizar la calidad percibida en contextos de muchas fallas y de poseer muy baja señalización (a diferencia de los sistemas existentes). Desarrollamos una metodología, basada en PSQA, que nos permite un control fino sobre la forma en que la señal de video es dividida en partes y la cantidad de redundancia agregada, como una función de la dinámica de los usuarios de la red. De esta forma es posible mejorar la robustez del sistema tanto como sea deseado, contemplando el límite de capacidad en la comunicación. En segundo lugar, presentamos un mecanismo estructurado para controlar la topología de la red. La selección de que usuarios servirán a que otros es importante para la robustez de la red, especialmente cuando los usuarios son heterogéneos en sus capacidades y en sus tiempos de conexión.Nuestro diseño maximiza la calidad global esperada (evaluada usando PSQA), seleccionado una topología que mejora la robustez del sistema. Además estudiamos como extender la red con dos servicios complementarios: el video bajo demanda (Video on Demand - VoD) y el servicio MyTV. El desafío en estos servicios es como realizar búsquedas eficientes sobre la librería de videos, dado al alto dinamismo del contenido. Presentamos una estrategia de "caching" para las búsquedas en estos servicios, que maximiza el número total de respuestas correctas a las consultas, considerando una dinámica particular en los contenidos y restricciones de ancho de banda. Nuestro diseño global considera escenarios reales, donde los casos de prueba y los parámetros de configuración surgen de datos reales de un servicio de referencia en producción. Nuestro prototipo es completamente funcional, de uso gratuito, y basado en tecnologías bien probadas de código abierto

Audiovisual Media Services in the EU. Next Generation Approach or Old Wine in New Barrels?

In this article, we analyse how the European legislator is currently responding to some of the recent changes in the media and communications environment with the adoption of the Audiovisual Media Services Directive. What is the European approach to address the challenges brought about by the technological changes in the audiovisual sector? How is the EU devising a future model for content regulation? The article also puts forward a number of critical remarks that should be taken into account in the framework of the debate on future content regulation, indicating where the AVMS Directive falls short.content regulation, audiovisual media services.

Context-Aware DVB-H Service Software Framework

Kontekstilla tarkoitetaan tietoa, jota voidaan käyttää jonkin kokonaisuuden tilanteen luonnehtimiseen. Kontekstitietoinen järjestelmä hyödyntää tätä kontekstia tuottaakseen merkityksellistä tietoa ja/tai palveluita järjestelmän käyttäjälle. Kontekstitietoisuus on yhä olennaisempi käsite tulevaisuuden mobiilipalveluissa ja -sovelluksissa. Personointi on myös olennainen käsite: sitä käytetään tarjotun sisällön ja käyttäjän kiinnostusten väliseen vertailuun. Mobiilipalveluntarjoajat tarvitsevat edullisia sisällönlähetystapoja. Eräs mahdollinen ratkaisu tähän on DVB-H-teknologian käyttö. DVB-H on digitaali-TV-spesifikaatio, joka on suunniteltu käytettäväksi mobiiliympäristöissä. DVB-H:n avulla voidaan tavoittaa suuri joukko asiakkaita erittäin kustannustehokkaasti. Kontekstitietoisuuden ja DVB-H-teknologian yhdistäminen mobiilipalveluksi on potentiaalisesti merkittävä skenaario: tämän kaltaisen palvelun käyttäjät pystyisivät kuluttamaan juuri sellaista sisältöä, jota he tarvitsevat ja josta he ovat kiinnostuneita; toisaalta palveluntarjoajat hyötyvät huomattavasti tästä rahallisesti. Edellä kuvattuun skenaarioon perustuen tässä diplomityössä esitetään i) kehitetty kontekstitietoisen DVB-H-palvelun ohjelmistokehys ja ii) referenssitoteutus, joka tehtiin ohjelmistokehyksen suunnittelun validoimiseksi. Tutkimuskysymys oli seuraavanlainen: millä tavoin kontekstitietoisuutta ja personointia voidaan hyödyntää DVB-H:n avulla välitetyn sisällön suosittelemiseksi käyttäjille. Kehitetty ohjelmistokehys suunniteltiin aiempaan tutkimukseen ja kontekstitietoisten mobiilipalveluiden ja -sovelluksien kehittämissuosituksiin perustuviin vaatimuksiin nojautuen. Ongelmat, jotka liittyvät kontekstitietoisuuden hyödyntämiseen DVB-H:ssa, käsiteltiin myös ohjelmistokehyksen kehittämisen täydentämiseksi. Referenssitoteutuksen vaatimusten mukainen toiminta validoitiin testiskenaarioilla. Skenaarioista saatujen tulosten avulla kontekstitietoisen DVB-H-palvelun kehittäjät voivat edelleen parantaa ohjelmistokehyksen toimintaa. Skenaariot osoittavat, että kontekstitietoisen mobiilisuosittelupalvelun kehittäminen DVB-H:lle ei ole vain mahdollista mutta myös suotavaa.Context is any information that can be used to characterize the situation of an entity. Context-aware system uses this context to provide relevant information and/or services to user. Context-awareness is a concept, which is increasingly both prevalent and essential in mobile services and applications. Additionally, personalization is a relevant concept in the field of mobile services. It is used to match the offered content and services to user's personal preferences. Mobile service providers require affordable content delivery methods. One viable alternative is DVB-H, a digital TV specification, which is specifically designed for mobile environments. Utilizing broadcasting, DVB-H is able to serve large amounts of customers in extremely cost-efficient way. Combining context-awareness with DVBH is potentially a remarkable scenario: users of this kind of service are able to consume content specific to their needs and preferences, while service providers gain maximal profits due to the inexpensive DVB-H delivery network. Based on this scenario, this Thesis presents i) a context-aware DVB-H service software framework that was developed and ii) a reference implementation, which was actualized to validate the framework design. The fundamental research question was: in what way can context-awareness and personalization be utilized in recommending DVB-H-mediated content to users. The developed framework was designed based on the requirements derived from earlier work related to context-aware system architectures and on guidelines related to designing context-aware mobile services and applications. DVB-H-specific context-awareness problems were considered to complete the design. The functioning of the reference implementation was confirmed with test scenarios, which validate the set requirements and provide valuable insights for the future developers of Context-Aware DVB-H Service. The scenarios validate that it is possible and even beneficial to create a context-aware mobile recommendation service, whose target content delivery medium is DVB-H

Digital Media Battleground

Current digital media distribution platforms continue their march towards streaming service-based infrastructures, delivering content to users when and where they want it: laptops, set top boxes, home entertainment systems, and the new ubiquity: mobile devices. This model was first demonstrated by utilizing the multicast backbone technology in the early 1990s and took the better part of a decade to make inroads in changing the way individuals consume broadcast, mainstream, and syndicated video media. It took the advent of streaming technology, high-speed internet adoption, and a willingness from content owners to license their treasured content with upstart streaming media platform companies. Digital music distribution showed consumers, content owners, and distribution channels what can happen when one player effectively creates a new, disruptive technology platform, i.e. Apple’s iTunes Music Store. Now content owners are afraid of a single distributor dictating the methods, prices, and channels by which their content reaches consumers. Today, streaming technology is making a play against the incumbent iTunes transactional model of Buy, Download, and Own digital distribution by providing varies models to consumers: integrated advertising-based, subscription-based, and traditional cable “packages” with integrated on-demand streaming, all of which retain no permanence or ownership for the end user. Content owners are treading carefully, trying to avoid the single, dominant point of distribution that Apple achieved in music distribution. The results of this are less optimal from both a market standpoint and especially the experience for consumers. Media companies frequently change the terms of their licenses, or drastically increasing their licensing costs, causing radical fluctuations in the long-term viability of the nascent distribution platforms. Consumers interact with this environment through complicated, multiparty subscriptions, multiple applications or web interfaces, umpteen logins, various bills, and a nebulous understanding and ability to sit down and watch premium content when and where they want it. The entire market is in its juvenile form, stretching, growing, and trying to find that balance of monetization and the critical mass of consumer adoption required to truly transform media consumption from the real-time, over-the-air broadcast format it has been since television’s inception, to a time-shifted, choose your own, content delivery system based around the internet as the delivery medium. In this paper we idealize the situation by analyzing the largest incumbents for each of the monetization models, provide input into their strength and weaknesses and finally analyze and postulate what we believe will the trends and concerns moving forward into this new digital media panacea

Video Multicasting Over 3g/umts Networks

Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 2009Thesis (M.Sc.) -- İstanbul Technical University, Institute of Science and Technology, 2009Bu çalışmada, UMTS şebekelerinde kullanılan farklı çeşitteki çoğa gönderim teknolojileri olumlu ve olumsuz yanları ile birlikte açıklanmıştır. 3GPP standardı, çoklu dağıtımı desteklemek için MBMS (Multimedia Broadcast/Multicast Services – Çoğul Ortam Yayın ve Çoklu Dağıtım Servisi) ile geliştirilmiştir. Bu tez esas olarak MBMS standardı, UMTS şebekelerine uygulanabilen video aktarım protokolleri ve teknikleri ile en önemli çoklu dağıtım servisi olarak görülen mobil televizyon uygulamasına odaklanmıştır. Teknolojik yeniliklerin başarısı ve kullanıcılar tarafından kabulü önemli ölçüde içeriğe dayalıdır. İçerik, kullanıcıların isteklerine göre tasarlanmalıdır ve mobil TV için önemli bir rol oynar. Bu tezde, kullanıcı istekleri ortaya konulmuş ve ayrıca mobil TV teknolojilerinin mevcut durumu, deneme sonuçları ve ticari olarak piyasaya sürülmesi tanımlanmıştır. Hangi durumlarda, nerelerde ve ne zaman bu hizmetlerin kullanılabileceğini tanımlamak için gerçekleştirilen araştırma sonuçları ortaya konulmuştur. Tezin bu konuya katkısı yeniden belirtilip, gelecekteki araştırmalara yön verecek bazı konulardan bahsedilmiştir.In this study different types of multicast technologies which are used in UMTS networks are introduced with their pros and cons. The 3GPP standard has been enhanced with MBMS (Multimedia Broadcast/Multicast Services) to support multicasting. This thesis mainly focuses on MBMS standard, video streaming protocols and techniques that are applicable to UMTS networks and especially the mobile TV service. Success and user acceptance of new technology innovations are highly depend on the content. It needs to be designed according to consumers’ demands and play an important role for mobile TV. In this thesis, users’ demands are introduced, also mobile TV technologies current status, trial results and commercial launches are described. Research results are presented which are performed to define in what situations, where and when the service can be used. The contributions are restated and some insight into future research directions is given.Yüksek LisansM.Sc

SUMMARIZATION AND VISUALIZATION OF DIGITAL CONVERSATIONS

Digital conversations are all around us: recorded meetings, television debates, instant messaging, blogs, and discussion forums. With this work, we present some solutions for the condensation and distillation of content from digital conversation based on advanced language technology. At the core of this technology we have argumentative analysis, which allow us to produce high-quality text summaries and intuitive graphical visualizations of conversational content enabling easier and faster access to digital conversations

A semiotic approach to ad-hoc networked environments

The aim of the work in this thesis is to develop a new approach of interacting with adhoc networked environments. These are networks where devices connect on demand with no underlying network infrastructure. The intention of this work is to develop these environments so that devices and services on these networks can publish their services, query for other services and connect with each other when required. The devices need to be able to perform these actions without prior knowledge of each other, therefore a theory of communication, semiotics, is presented. Ad-hoc networks provide an appropriate test-bed for this application of semiotics as they allow services to `know' about each other and communicate with one another. By using semiotics, we aim to create a representation of communication that allows a system to communicate within the networked environment and ask for services and connections as well as interact with users and provide. This way a user can demand something from the surrounding environment and the elements within this environment can communicate with each other to provide the service the user required. To create an effective model for this representation, various research areas will be discussed such as smart environments, natural language processing, multicast environments and human computer interaction. Principles will be used from all these areas to implement an approach of interacting with smart environments. Different types of smart environments, such as as smart homes and m-commerce environments, will be used to observe how di erent contexts a ect communication. A prototype system was realised for proof of concept and evaluated by subjects. This work highlighted the feasibility of this approach and opened a new area worthwhile of further research.EThOS - Electronic Theses Online ServiceGBUnited Kingdo