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Liu, Jiayi. "Multiple Live Videos Delivery in Underprovisioned Networks". Télécom Bretagne, 2013. http://www.telecom-bretagne.eu/publications/publication.php?idpublication=14166.
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Avec la prolifération de nouveaux appareils (tels que les smartphones et tablettes), de nouveaux services multimédias (e. G. Vidéo en direct généré par les utilisateurs), ainsi que de nouvelles techniques de diffusion (e. G. Le streaming adaptatif) sont apparues. Les scientifiques observent une croissance formidable du trafic Internet lié au streaming vidéo, au point que les réseaux de distribution peuvent être insuffisamment provisionné. Ce problème est particulièrement sévère pour les vidéos en direct en raison de sa condition en temps réel. Dans cette thèse, nous nous concentrons sur des solutions de diffusion vidéo en direct efficaces en bande passante depuis les réseaux sous-provisionnés. Nous avons deux contributions principales: (1) un système basé sur les réseaux pair-à-pair(P2P) pour partager des vidéos en direct générées par les utilisateurs, et (2) un système de streaming des vidéos en direct en débit adaptatif reposant sur un Content Delivery Network(CDN). Dans le cas du système de partage de vidéos basé sur les réseaux P2P, un problème apparaît quand il y a de multiples vidéos dans le système car chaque pair doit alors allouer ses ressources parmi de nombreux réseaux P2P. Nous avons conçu différents algorithmes pour ce problème et montré comment des solutions optimales peuvent être calculées rapidement. Ensuite, nous avons étudié le problème de diffuser des vidéos en direct adaptatif dans le CDN. Pour ce problème, nous avons identifié un modèle de « streaming discrétisé », et formulé un problème d'optimisation général qui est NP-complet. En outre, nous avons présenté un algorithme rapide, facile à mettre en oeuvre, et quasi-optimal pour un scénario spécifique. Ce travail est la première étape vers le streaming des vidéos en direct multiples avec débit adaptatif dans CDN. Enfin, nous avons étendu le modèle discrétisé général à un modèle centré sur les utilisateurs, qui maximise la satisfaction d'une population d'utilisateurs. Nous avons présenté un système pratique, qui utilise efficacement l'infrastructure CDN pour fournir des flux vidéos en direct aux téléspectateurs. Les avantages de nos approches sur la réduction de la capacité de l'infrastructure CDN sont validés par un ensemble de simulations à grande échelle réalistes. Plus généralement, cette thèse explore des solutions de diffusion vidéo en direct efficace dans des réseaux de distribution sous-provisionnés pour plusieurs technologies de streaming. L'objectif est d'utiliser au maximum la bande passante de noeuds relais (pairs dans P2P et les équipements de CDN) pour atteindre un objectif d'optimisationThe proliferation of new devices (such as smartphones and tablets) promotes new multimedia services (e. G. User-generated live video broadcasting), as well as new streaming techniques (e. G. Rate-adaptive streaming). As a matter of fact, scientists observe a formidable, sustainable growth of Internet traffic related to video streaming. Yet, network infrastructures struggle to cope with this growth and it is now frequent that a delivery network is insufficiently provisioned. Such underprovisioning problem is more severe for live videos due to its real-time requirement. In this thesis, we focus on bandwidth efficient video delivery solutions for live streaming in underprovisioned video delivery networks. Specifically, we have two main contributions: (1) a user-generated live videos sharing system based on peer-to-peer (P2P) technique, and (2) a live rate-adaptive streaming system based on Content Delivery Network (CDN). First of all, we built an multioverlay P2P video sharing system which allows Internet users to broadcast their own live videos. Typically, such a system consists of multiple P2P live video streaming systems, and faces the problem of finding a suitable allocation of peer upload bandwidth. We designed various bandwidth allocation algorithms for this problem and showed how optimal solutions can be efficiently computed. Then, we studied the problem of delivering live rate-adaptive streams in the CDN. We identified a discretize streaming model for multiple live videos in modern CDNs. We formulated a general optimization problem through Integer Linear Programming (ILP) and showed that it is NP-complete. Further, we presented a fast, easy to implement, and near-optimal algorithm with approved approximation ratios for a specific scenario. This work is the first step towards streaming multiple live rate-adaptive videos in CDN and provides a fundamental theoretical basis for deeper investigation. Last, we further extended the discretized streaming model into an user-centric one which maximizes the overall satisfaction of an user population. Further, we presented a practical system, which efficiently utilizes CDN infrastructure to deliver live video streams to viewers in dynamic and large-scale CDNs. The benefits of our approaches on reducing the CDN infrastructure capacity is validated through a set of realistic trace-driven large-scale simulations. All in one, this thesis explores bandwidth efficient live video delivery solutions in underprovisioned delivery network for multiple streaming technologies. The aim is to maximally utilize the bandwidth of relay nodes (peers in P2P and forwarding equipments in CDN) to achieve an optimization goal
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But, Jason. "A novel MPEG-1 partial encryption scheme for the purposes of streaming video". Monash University, Dept. of Electrical and Computer Systems Engineering, 2004. http://arrow.monash.edu.au/hdl/1959.1/9709.
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Lin, Ching-Ping. "Streaming video for parental involvement education". CSUSB ScholarWorks, 2003. https://scholarworks.lib.csusb.edu/etd-project/2473.
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The purpose of this project is to develop a way of communication between school and parents. It aims to help parents to be more involved in their children's education. One of the main aspects and focus of this project is the analysis of the use of streaming video.
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Lang, Linda Sue. "An analysis of instructor streaming videos on the practice sets in the Accounting 1 online course at Chippewa Valley Technical College". Menomonie, WI : University of Wisconsin--Stout, 2004. http://www.uwstout.edu/lib/thesis/2004/2004langl.pdf.
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Nair, Binu Muraleedharan. "Learning Latent Temporal Manifolds for Recognition and Prediction of Multiple Actions in Streaming Videos using Deep Networks". University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1429532297.
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MACHADO, NETO Luiz Teixeira. "Avaliação da qualidade de vídeos transmitidos via vídeo streaming em ambientes residenciais". Universidade Federal de Campina Grande, 2015. http://dspace.sti.ufcg.edu.br:8080/jspui/handle/riufcg/593.
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LUIZ TEIXEIRA MACHADO NETO - DISSERTAÇÃO PPGCC 2015..pdf: 936539 bytes, checksum: 75e4ab7774a9d4c965e23ec09254fc86 (MD5)Made available in DSpace on 2018-05-07T15:46:17Z (GMT). No. of bitstreams: 1 LUIZ TEIXEIRA MACHADO NETO - DISSERTAÇÃO PPGCC 2015..pdf: 936539 bytes, checksum: 75e4ab7774a9d4c965e23ec09254fc86 (MD5) Previous issue date: 2015-03-01
A utilização de serviços de streaming cresceu bastante nos últimos anos, por meio de sistemas como Youtube, Hulu, Netflix, Vimeo, etc. Utilizando o stream, os vídeos são transmitidos e exibidos em tempo real e em qualquer lugar do mundo por meio da internet. Muitosusuáriosdestessistemasosutilizamemsuaresidênciaondeébastante comumencontrarumaredesemfio(devidoàmobilidadequesepodealcançarpormeio deste tipo de rede). Apesar de mais mobilidade, uma rede sem fio está mais suscetível a interferências do que a rede cabeada e, por isso, um vídeo pode ter sua imagem degradada com mais facilidade. Neste trabalho, é avaliada a transmissão de vídeos via stream para descobrir se o vídeo realmente é degradado pela transmissão; se tipos de conteúdos diferentes afetam a qualidade do vídeo recebido; e se de acordo com o padrão de compressão utilizado, é possível observar melhorias na qualidade do vídeo recebido. Por meio de uma abordagem experimental com um design de experimentos fatorial completo, foram feitas transmissões de vídeos utilizando o H.264, o HEVC e o MPEG-4; padrões mais utilizados atualmente. Além de definir os padrões, foram definidas outras variáveis: porcentagem de ocupação do canal de transmissão (com o objetivo de avaliar a degradação dos vídeos de acordo com a competição que a rede está sofrendo); potência do sinal de transmissão (com o objetivo de avaliar o impacto da qualidade do sinal da rede no vídeo recebido); quantidade de movimento no vídeo (para avaliar se a quantidade de movimento que o vídeo exibe impacta na sua qualidade). Nos experimentos, foi utilizado um ambiente residencial que conta as interferências de outras redes, exatamente como pode acontecer em um ambiente real. Para definir as porcentagens de ocupação, foram realizados experimentos para medição da capacidade máxima de transmissão da rede de testes. Em se tratando da quantidade de movimento, foi necessário fazer uma classificação prévia dos vídeos de acordo com características espaciais e temporais de cada vídeo. Os vídeos foram separados em três categorias e dentro dessas categorias, três vídeos foram escolhidos aleatoriamente para participar dos experimentos. Os resultados mostram que o HEVC obteveamelhormédiaparaasmétricasdequalidadedevídeoescolhidas, sendoocodec que menos perde qualidade numa transmissão sem fio. Também foi possível observar que a quantidade de movimento foi o parâmetro que mais influenciou na qualidade do vídeos nos experimentos realizados.
The use of streaming services has grown significantly in recent years, through systems such as Youtube, Hulu, Netflix, Vimeo, etc. Using the stream, videos are transmitted and displayed in real time and from anywhere in the world via the Internet. Many users of these systems use the same in their homes where it is quite common to find a wireless network (due to the mobility we can achieve through this type of computer network). In spite of having more mobility, a wireless network is more susceptible to interference than the wired network so a video can have its picture degraded more easily just because it is transmitted over a wireless network. We evaluate the transmission of videos via stream to find out whether the video is actually degraded by transmission; if different types of content affect the quality of the received video; and if there are compression standarts (H.264 and MPEG-4 HEVC, the most currently used) which ensure a better received video quality. Through an experimental approach with a design of full factorial experiments, several transmissions of videos were made in the three chosen standarts. In addition to defining the standarts, other variables were defined as: transmission channel occupancy percentage (in order to evaluate the degradation of videos according to occupation); power transmission signal (in order to assess the impact of network signal quality in the video received); amount of motion in the video (to evaluate whether the amount of motion the video displays impacts on its quality). For the experiments we used a residential environment that has all the interference from other networks, just as it can happen in a real environment. To set the occupancy percentages, experiments were performed to measure the maximum transmission capacity of the test network. Concerning the quantity of movement, it was necessary to make a preliminary classification of videos according to spatial and temporal characteristics of each one. The videos were separated into three categories and within these categories, three videos were chosen at random to participate in the experiments. The results show that the HEVC achieved the highest average for quality metricsofthechosenvideos,andthecodecistheonethatloseslessqualityinawireless transmission. The amount of movement affects the quality of the received video, and the greater the amount of motion, the bigger the loss of image quality.
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Mittal, Ashutosh. "Novel Approach to Optimize Bandwidth Consumption for Video Streaming using Eye Tracking". Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-212061.
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Recent leaps in eye tracking technology have made it possible to enable eye tracking as a cheap, reliable and efficient addition to the human computer interaction technologies. This thesis looks into the possibility of utilizing it for client aware video streaming. Increasingly people are consuming high quality video content on wireless network devices, thus there is need to optimize bandwidth consumption for efficient delivery of such high resolution content, both for 2D and 360°videos.This work proposes SEEN (Smart Eye-tracking Enabled Networking), a novel approach to streaming video content using real time eye tracking information. This uses HEVC video tiling techniques to display high and low qualities in the same video frame depending on where the user is looking. The viability of proposed approach is validated using extensive user testing conducted on a Quality of Experience (QoE) testbed which was also developed as part of this thesis. Test results show significant bandwidth savings of up to 71% for 2D videos on standard 4K screens, and up to 83% for 360°videos on Virtual Reality (VR) headsets for acceptable QoE ratings. A comparative study on viewport tracking and eye tracking for VR headsets is also included in the thesis in order to further advocate the necessity of eye tracking.This research was conducted in collaboration with Ericsson, Tobii and KTH under the umbrella project SEEN: Smart Eye-tracking Enabled Networking.Nya framsteg inom ögonstyrningsteknologi har möjliggjort att betrakta ögonstyrning (o.k.s. eyetracking) som ett billigt, pålitligt och effektivt tillägg till teknologier för människa-dator interaktion. Det här examensarbetet utforskar möjligheten att använda ögonstyrning för klientmedveten videoströmning. Allt fler personer förbrukar videoinnehåll av hög kvalitet genom trådlösa nätverk, därmed finns det ett behov av att optimera bandbreddskonsumtionen för effektiv leverans av ett sådant högkvalitativt innehåll, både för 2Doch 360°-videor.Det här arbetet introducerar SEEN (Smart Eye-tracking Enabled Networking), en ny approach för att strömma videoinnehåll, som bygger på realtidsinformation från ögonstyrning. Den använder HEVC-metoder för rutindelning av video för att visa högkvalitativt och lågkvalitativt innehåll i samma videoram, beroende på vart användaren tittar. Lönsamheten av den föreslagna approachen validerades med hjälp av omfattande användartester utförda på en testbädd för upplevelsekvalité (Quality of Experience, QoE) som också utvecklades som en del av det här examensarbetet. Testresultaten visar betydande bandbreddsbesparingar på upp till 71% för 2D-videor på vanliga 4K-skärmar samt upp till 83% för 360°-videor på VR-headset för acceptabla QoE-betyg. En komparativ studie om viewport tracking och ögonstyrning i VR-headset är också inkluderad i det här examensarbetet för att ytterligare förespråka behovet av ögonstyrning.Denna forskning genomfördes i samarbete med Ericsson, Tobii och KTH under paraplyprojektet SEEN: Smart Eye-tracking Enabled Networking.
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Ejembi, Oche Omobamibo. "Enabling energy-awareness for internet video". Thesis, University of St Andrews, 2016. http://hdl.handle.net/10023/9768.
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Continuous improvements to the state of the art have made it easier to create, send and receive vast quantities of video over the Internet. Catalysed by these developments, video is now the largest, and fastest growing type of traffic on modern IP networks. In 2015, video was responsible for 70% of all traffic on the Internet, with an compound annual growth rate of 27%. On the other hand, concerns about the growing energy consumption of ICT in general, continue to rise. It is not surprising that there is a significant energy cost associated with these extensive video usage patterns. In this thesis, I examine the energy consumption of typical video configurations during decoding (playback) and encoding through empirical measurements on an experimental test-bed. I then make extrapolations to a global scale to show the opportunity for significant energy savings, achievable by simple modifications to these video configurations. Based on insights gained from these measurements, I propose a novel, energy-aware Quality of Experience (QoE) metric for digital video - the Energy - Video Quality Index (EnVI). Then, I present and evaluate vEQ-benchmark, a benchmarking and measurement tool for the purpose of generating EnVI scores. The tool enables fine-grained resource-usage analyses on video playback systems, and facilitates the creation of statistical models of power usage for these systems. I propose GreenDASH, an energy-aware extension of the existing Dynamic Adaptive Streaming over HTTP standard (DASH). GreenDASH incorporates relevant energy-usage and video quality information into the existing standard. It could enable dynamic, energy-aware adaptation for video in response to energy-usage and user ‘green' preferences. I also evaluate the subjective perception of such energy-aware, adaptive video streaming by means of a user study featuring 36 participants. I examine how video may be adapted to save energy without a significant impact on the Quality of Experience of these users. In summary, this thesis highlights the significant opportunities for energy savings if Internet users gain an awareness about their energy usage, and presents a technical discussion how this can be achieved by straightforward extensions to the current state of the art.
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Theriault, Shelli. "Enhancing visual arts instruction through technology : how the integration of Discovery Education's United Streaming Videos and the interactive SMART Board is changing instruction in the art room /". Abstract Full Text (HTML) Full Text (PDF), 2007. http://eprints.ccsu.edu/archive/00000437/02/1933FT.htm.
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Thesis (M.S.) -- Central Connecticut State University, 2007.Thesis advisor: Cora Marshall. "... in partial fulfillment of the requirements for the degree of Master of Science in Art Education." Includes bibliographical references (leaves 77-80). Also available via the World Wide Web.
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Corbillon, Xavier. "Enable the next generation of interactive video streaming". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2018. http://www.theses.fr/2018IMTA0103/document.
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Les vidéos omnidirectionnelles, également appelées vidéos sphériques ou vidéos360°, sont des vidéos avec des pixels enregistrés dans toutes les directions de l’espace. Un utilisateur qui regarde un tel contenu avec un Casques de Réalité Virtuelle (CRV) peut sélectionner la partie de la vidéo à afficher, usuellement nommée viewport, en bougeant la tête. Pour se sentir totalement immergé à l’intérieur du contenu, l’utilisateur a besoin de voir au moins 90 viewports par seconde en 4K. Avec les technologies de streaming traditionnelles, fournir une telle qualité nécessiterait un débit de plus de100 Mbit s−1, ce qui est bien trop élevé. Dans cette thèse, je présente mes contributions pour rendre possible le streaming de vidéos omnidirectionnelles hautement immersives sur l’Internet. On peut distinguer six contributions : une proposition d’architecture de streaming viewport adaptatif réutilisant une partie des technologies existantes ; une extension de cette architecture pour des vidéos à six degrés de liberté ; deux études théoriques des vidéos à qualité spatiale non-homogène; un logiciel open source de manipulation des vidéos 360°; et un jeu d’enregistrements de déplacements d’utilisateurs regardant des vidéos 360°Omnidirectional videos, also denoted as spherical videos or 360° videos, are videos with pixels recorded from a given viewpoint in every direction of space. A user watching such an omnidirectional content with a Head Mounted Display (HMD) can select the portion of the videoto display, usually denoted as viewport, by moving her head. To feel high immersion inside the content a user needs to see viewport with 4K resolutionand 90 Hz frame rate. With traditional streaming technologies, providing such quality would require a data rate of more than 100 Mbit s−1, which is far too high compared to the median Internet access band width. In this dissertation, I present my contributions to enable the streaming of highly immersive omnidirectional videos on the Internet. We can distinguish six contributions : a viewport-adaptive streaming architecture proposal reusing a part of existing technologies ; an extension of this architecture for videos with six degrees of freedom ; two theoretical studies of videos with non homogeneous spatial quality ; an open-source software for handling 360° videos ; and a dataset of recorded users’ trajectories while watching 360° videos
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Abousabea, Emad Mohamed Abd Elrahman. "Optimization algorithms for video service delivery". Thesis, Evry, Institut national des télécommunications, 2012. http://www.theses.fr/2012TELE0030/document.
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L'objectif de cette thèse est de fournir des algorithmes d'optimisation pour l'accès aux services vidéo qu’ils soient non-gérés (Internet TV) ou gérés (IPTV). Nous étudions des statistiques récentes concernant les services vidéo non-gérés comme YouTube et nous proposons des techniques d'optimisation appropriées qui pourraient améliorer l'accès aux fichiers vidéos et réduire le coût de cet accès. En outre, l’analyse des coûts joue un rôle important dans les décisions qui concernent la mise en cache des fichiers vidéos et celles liées au choix des périodes temporelles d'hébergement de ces fichiers sur les serveurs. En ce qui concerne les services vidéo gérés appelés IPTV, nous avons mené des expériences sur une architecture ouverte IPTV-collaboration entre différents opérateurs. Ce modèle est analysé selon un critère de coût d’investissement et d'exploitation à l'intérieur de la sphère domestique. En outre, nous avons introduit une solution d’optimisation dynamique de l'arbre « minimum spanning tree » (MST) pour le service IPTV multicast. Lors d’un accès nomade, les arbres statiques pourraient être incapables de fournir le service de manière efficace vu que l'utilisation de la bande passante augmente aux côté des points de streaming (racines de la topologie). Finalement, nous étudions des mesures de sécurité fiables en streaming vidéo basées sur la méthodologie de la chaîne de hachage et nous proposons un nouvel algorithme hybride. Nous effectuons des comparaisons entre les différentes manières utilisées dans la réalisation de la fiabilité des chaînes de hachage basées sur les classifications génériquesThe aim of this thesis is to provide optimization algorithms for accessing video services either in unmanaged or managed ways. We study recent statistics about unmanaged video services like YouTube and propose suitable optimization techniques that could enhance files accessing and reduce their access costs. Moreover, this cost analysis plays an important role in decision making about video files caching and hosting periods on the servers. Under managed video services called IPTV, we conducted experiments for an open-IPTV collaborative architecture between different operators. This model is analyzed in terms of CAPEX and OPEX costs inside the domestic sphere. Moreover, we introduced a dynamic way for optimizing the Minimum Spanning Tree (MST) for multicast IPTV service. In nomadic access, the static trees could be unable to provide the service in an efficient manner as the utilization of bandwidth increases towards the streaming points (roots of topologies). Finally, we study reliable security measures in video streaming based on hash chain methodology and propose a new algorithm. Then, we conduct comparisons between different ways used in achieving reliability of hash chains based on generic classifications
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Čeněk, Radek. "Audio/Video streaming". Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2015. http://www.nusl.cz/ntk/nusl-220405.
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This thesis introduces the reader in detail with the problem of audio / video streaming overtheInternet.IntroducestechnologiesMySQL,PHP,JavaScriptandffmpegfurthermore. There is little research which examines presented similar solutions. Creating video library program shows the complexity of the problem and its possible solution. The work also finding how is compression difficult for the server.
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Ben, Yahia Mariem. "Low latency video streaming solutions based on HTTP/2". Thesis, Ecole nationale supérieure Mines-Télécom Atlantique Bretagne Pays de la Loire, 2019. http://www.theses.fr/2019IMTA0136/document.
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Les techniques adaptatives de transmission vidéo s’appuient sur un contenu qui est encodé à différents niveaux de qualité et divisé en segments temporels. Avant de télécharger un segment, le client exécute un algorithme d’adaptation pour décider le meilleur niveau de qualité à considérer. Selon les services, ce niveau de qualité doit correspondre aux ressources réseaux disponibles, mais aussi à d’autres éléments comme le mouvement de tête d’un utilisateur regardant une vidéo immersive (à 360°) afin de maximiser la qualité de la portion de la vidéo qui est regardée. L’efficacité de l’algorithme d’adaptation a un impact direct sur la qualité de l’expérience finale. En cas de mauvaise sélection de segment, un client HTTP/1 doit attendre le téléchargement du prochain segment afin de choisir une qualité appropriée. Dans cette thèse, nous proposons d’utiliser le protocole HTTP/2 pour remédier à ce problème. Tout d’abord, nous nous focalisons sur le service de vidéo en direct. Nous concevons une stratégie de rejet d’images vidéo quand la bande passante est très variable afin d’éviter les arrêts fréquents de la lecture vidéo et l’accumulation des retards. Le client doit demander chaque image vidéo dans un flux HTTP/2 dédié pour contrôler la livraison des images par appel aux fonctionnalités HTTP/2 au niveau des flux concernées. Ensuite, nous optimisons la livraison des vidéos immersives en bénéficiant de l’amélioration de la prédiction des mouvements de têtes de l’utilisateur grâce aux fonctionnalités d’initialisation et de priorité de HTTP/2. Les résultats montrent que HTTP/2 permet d’optimiser l’utilisation des ressources réseaux et de s’adapter aux latences exigées par chaque serviceAdaptive video streaming techniques enable the delivery of content that is encoded at various levels of quality and split into temporal segments. Before downloading a segment, the client runs an adaptation algorithm to determine the level of quality that best matches the network resources. For immersive video streaming this adaptation mechanism should also consider the head movement of a user watching the 360° video to maximize the quality of the viewed portion. However, this adaptation may suffer from errors, which impact the end user’s quality of experience. In this case, an HTTP/1 client must wait for the download of the next segment to choose a suitable quality. In this thesis, we propose to use the HTTP/2 protocol instead to address this problem. First, we focus live streaming video. We design a strategy to discard video frames when the band width is very variable in order so as to avoid the rebuffering events and the accumulation of delays. The customer requests each video frame in an HTTP/2 stream which allows to control the delivery of frames by leveraging the HTTP/2 features at the level of the dedicated stream. Besides, we use the priority and reset stream features of HTTP/2 to optimize the delivery of immersive videos. We propose a strategy to benefit from the improvement of the user’s head movements prediction overtime. The results show that HTTP/2 allows to optimize the use of network resources and to adapt to the latencies required by each service
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Chatzidrossos, Ilias. "P2P Live Video Streaming". Licentiate thesis, KTH, Communication Networks, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-12373.
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The ever increasing demand for video content directed the focus of researchfrom traditional server-based schemes to peer-to-peer systems for videodelivery. In such systems, video data is delivered to the users by utilizing theresources of the users themselves, leading to a potentially scalable solution.Users connect to each other, forming a p2p overlay network on top of theInternet and exchange the video segments among themselves. The performanceof a p2p system is characterized by its capability to deliver the videocontent to all peers without errors and with the smallest possible delay. Thisconstitutes a challenge since peers dynamically join and leave the overlay andalso contribute different amounts of resources to the system.The contribution of this thesis lies in two areas. The first area is theperformance evaluation of the most prominent p2p streaming architectures.We study the streaming quality in multiple-tree-based systems. We derivemodels to evaluate the stability of a multiple tree overlay in dynamic scenariosand the efficiency of the data distribution over the multiple trees. Then, westudy the data propagation in mesh-based overlays. We develop a generalframework for the evaluation of forwarding algorithms in such overlays anduse this framework to evaluate the performance of four different algorithms.The second area of the thesis is a study of streaming in heterogeneous p2poverlays. The streaming quality depends on the aggregate resources that peerscontribute to the system: low average contribution leads to low streamingquality. Therefore, maintaining high streaming quality requires mechanismsthat either prohibit non-contributing peers or encourage contribution. In thisthesis we investigate both approaches. For the former, we derive a model tocapture the evolution of available capacity in an overlay and propose simpleadmission control mechanisms to avoid capacity drainage. For the latter, inour last work, we propose a novel incentive mechanism that maximizes thestreaming quality in an overlay by encouraging highly contributing peers tooffer more of their resources.
QC 20100506
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Plissonneau, Louis. "Network tomography from an operator perspective". Thesis, Paris, ENST, 2012. http://www.theses.fr/2012ENST0033/document.
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Le domaine de la mesure des caractéristiques du trafic transitant sur un réseau a été largement traité par une vaste communauté de chercheurs, en premier lieu pour répondre aux attentes des opérateurs fournisseurs d'accès à Internet. En effet, leur première préoccupation est de savoir quel type de trafic ils doivent transporter. Une des principales caractéristiques de l'Internet est qu'il évolue très vite, de sorte que le besoin de mesures du trafic grand public ne se tarit jamais. Dans ce travail, nous abordons la question de la mesure du trafic Internet grand public par deux perspectives différentes: les mesures passives et les mesures actives. Dans la première partie de cette thèse, nous capturons et analysons passivement les statistiques des connections d'utilisateurs d'Internet durant plus d'une semaine. Nous utilisons ces données pour réviser et approfondir notre connaissance du trafic Internet résidentiel. Ensuite, nous utilisons des méthodes de regroupement pour créer des ensembles d'utilisateurs en fonctions des applications qu'ils utilisent. Nous apprenons donc qu'une vaste majorité des clients se connectent à Internet principalement pour surfer sur le Web et regarder des vidéos en streaming. Ces données nous servent aussi à évaluer de nouvelles possibilités de contrôler le trafic d'une plateforme ADSL. Comme la principale partie du trafic provient du vidéo streaming, nous prenons plusieurs instantanés de ce trafic avec des captures paquet durant une période de plusieurs années, ceci pour comprendre précisément l'évolution de ce trafic. De plus, nous analysons et relions la performance du vidéo streaming, définie par des indicateurs de qualité de service, au comportement des utilisateurs de ce service. Dans la deuxième partie de cette thèse, nous tirons parti de cette connaissance pour concevoir une sonde active capable de mesurer la qualité d'expérience des sites de vidéo streaming. Nous avons modélisé la lecture des vidéos \emph{streaming} pour pouvoir déterminer leur qualité telle qu'elle est perçue par les utilisateurs. Grâce à cet outil, nous pouvons comprendre l'impact de la sélection du serveur vidéo et du serveur DNS sur la perception de la qualité vidéo par l'utilisateur. De plus, la possibilité de réaliser des mesures depuis divers opérateurs, nous permet de détailler les politiques de distribution vidéo utilisées par les sites de streamingNetwork tomography is the study of a network's traffic characteristics using measures. This subject has already been addressed by a whole community of researchers, especially to answer the need for knowledge of residential Internet traffic that ISPs have to carry. One of the main aspects of the Internet is that it evolves very quickly, so that there is a never ending need for Internet measurements. In this work, we address the issue of residential Internet measure from two different perspectives: passive measurements and active measurements. In the first part of this thesis, we passively collect and analyse statistics of residential users' connections spanning over a whole week. We use this data to update and deepen our knowledge of Internet residential traffic. Then, we use clustering methods to form groups of users according to the application they use. This shows how the vast majority of customers are now using the Internet mainly for Web browsing and watching video Streaming. This data is also used to evaluate new opportunities for managing the traffic of a local ADSL platform. As the main part of the traffic is video streaming, we use multiple snapshots of packet captures of this traffic over a period of many years to accurately understand its evolution. Moreover we analyse and correlate its performance, defined out of quality of service indicators, to the behavior of the users of this service. In the second part of this thesis, we take advantage of this knowledge to design a new tool for actively probing the quality of experience of video streaming sites. We have modeled the playback of streaming videos so that we are able to figure out its quality as perceived by the users. With this tool, we can understand the impact of the video server selection and the DNS servers on the user's perception of the video quality. Moreover the ability to perform the experiments on different ISPs allows us to further dig into the delivery policies of video streaming sites
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Bösken, Michael. "Streaming-Video und Web-TV /". Hamburg : Diplomica-Verl, 2007. http://www.diplom.de/katalog/arbeit/10452.
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Bösken, Michael. "Streaming Video & Web TV /". Hamburg : Diplomica Verl, 2007. http://www.diplom.de/katalog/arbeit/10452.
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Johansson, Markus, e Sebastian Andersson. "Multi-Video Streaming with DASH". Thesis, Linköpings universitet, Institutionen för datavetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-138755.
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Multi-video streaming allows the viewer to interact with the stream by choosing andswitching between several different camera angles to view the stream from. For this reportwe implement and evaluate adaptive multi-video streaming with dash.js. With the help ofdash.js and self-made additions, multiple parallel video streams which are synchronized intime are implemented to provide a good user experience with smooth switching betweenstreams. These streams will be delivered according to dash.js own HTTP-based AdaptiveStreaming algorithms to achieve adaptive streams for varying conditions. In order to optimizethe usage of the available bandwidth in terms of video quality in a multi-videoenvironment we implement probabilities of camera switching to adapt qualities and allocatedbandwidth of streams. By utilizing the functions of dash.js we create two prefetchingpolicies and analyze these results together with the standard non-prefetch dash.js implementationin a multi-view video environment. Our results present the improvements interms of stalling with a prefetch implementation and the possibility of a good policy tofurther optimize a multi-view video implementation in terms of stalling, quality and bandwidthusage. Evaluation of dash.js compatibility for a multi-view video environment is alsodiscussed where pros and cons of dash.js in their current state are presented.
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Planer, Jan. "Mobilní aplikace zpracování obrazu". Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-264975.
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This thesis addresses video streaming from smartphone to smartwatch. The main goal of the thesis is to find a way how to handle the limited hardware features of the watch and make video streaming as fast and smooth as possible. A part of this work is focused on implementation of client-server application, which streams video from Android device to Tizen smartwatch over Bluetooth channel.
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Lin, Yu-Ting. "Analyse de performance des services de vidéo streaming dans les réseaux mobiles". Thesis, Paris, ENST, 2016. http://www.theses.fr/2016ENST0080/document.
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Le trafic de vidéo streaming étant en très forte augmentation dans les réseaux mobiles, il devient essentiel pour les opérateurs de tenir compte des spécificités de ce trafic pour bien dimensionner et configurer le réseau. Dans cette thèse, nous nous intéressons à la modélisation du trafic de vidéo streaming dans les réseaux mobiles. Pour le trafic de vidéo streaming en temps-réel, nous obtenons une forme analytique pour une métrique de qualité de service (QoS) importante, le taux de perte de paquets, et utilisons ce modèle à faire du dimensionnement. Pour le trafic de vidéo streaming de type HTTP adaptatif, nous proposons et analysons d’autres métriques de QoS comme le bitrate moyen, le taux de déficit vidéo et le surplus de buffer, afin de trouver le bon compromis entre résolution de la vidéo et fluidité de la diffusion vidéo. Nous étudions par simulation l’impact de quelque paramètres clés du systéme. Nous montrons que l’utilisation de segments de vidéo courts, d’un nombre réduit d’encodages vidéos et de l’ordonnancement de type round robin améliore la fluidité de la vidéo tout en diminuant sa résolution. Nous proposons par ailleurs d’adapter le nombre des segments téléchargés dans une requête HTTP de sorte que chaque requête corresponde au même volume de données. Enfin, nous appliquons les techniques de l’apprentissage automatique pour analyser la corrélation entre les caracteristiques du système et la qualité d’expérience (QoE) des utilisateursAs the traffic of video streaming increases significantly in mobile networks, it is essential for oper- ators to account for the features of this traffic when dimensioning and configuring the network. The focus of this thesis is on traffic models of video streaming in mobile networks. For real-time video streaming traffic, we derive an analytical form for an important Quality-of-Service (QoS) metric, the packet outage rate, and utilize the model for dimensioning. For HTTP adaptive video streaming traffic, we propose and evaluate other QoS metrics such as the mean video bit rate, the deficit rate and the buffer surplus, so as to find the good trade-off between video resolution and playback smoothness. We study by simulation the impacts of some key parameters of the system. We show that using smaller chunk durations, fewer video coding rates and round-robin scheduling may provide a smoother video playback but decrease the mean video resolution. We also propose to adapt the number of chunks downloaded in an HTTP request so that each HTTP request has the same data volume. Finally, we apply machine learning techniques to analyze the correlation between system characteristics and the quality of experience (QoE) of users
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Karagkioules, Theodoros. "Optimization of adaptive video streaming in mobile networks". Electronic Thesis or Diss., Institut polytechnique de Paris, 2019. http://www.theses.fr/2019IPPAT005.
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Grâce à l'évolution des technologies des Réseaux et des dispositifs mobiles (téléphones, tablettes), les utilisateurs sont amenés à utiliser de plus en plus de services à forte consommation de bande passante, comme le streaming vidéo. Selon un report de CISCO, en 2017, le streaming vidéo mobile représentait 58% du trafic de données mobile mondial, un pourcentage qui devrait atteindre 79% d’ici 2022. Ce trafic est principalement constitué de vidéo à la demande (VoD) sur HTTP Adaptive Streaming (HAS), qui est désormais une technologie incontournable des dispositifs mobiles. Les solutions HAS utilisent des algorithmes d’adaptation de débit, qui ajustent de manière transparente le débit du flux multimédia pour compenser les conditions changeantes du réseau. Néanmoins, la transmission vidéo sur les réseaux mobiles fait toujours face à des défis importants car ces réseaux se caractérisent par une variation continuelle du débit, principalement attribuable aux effets physiques associés à la propagation radio ainsi qu’à la mobilité des utilisateurs (interruptions de session). L’objectif est de traiter ces défis de la diffusion vidéo dans les réseaux mobiles et de proposer des solutions optimisées sous deux perspectives distinctes. Dans la perspective des fournisseurs de services vidéo Over the Top (OTT), nous proposons de nouveaux algorithmes d’adaptation du débit mobile; tandis que, dans la perspective des vendeurs d’équipements de télécommunication et des opérateurs réseau, nous explorons les avantages que la collecte du trafic HAS et de son analyse peuvent apporter à la gestion du réseau. Plus précisément, lors de l’évaluation des performances de systèmes HAS actuels, nous avons identifié 3 problèmes : [1] concerne les données d’entrée qui pilotent les algorithmes d’adaptation de débit. Bien que plusieurs algorithmes d’adaptation de débit aient été introduits pour améliorer la qualité d’expérience (QoE) de l’utilisateur, seuls quelques-uns exploitent les informations provenant des couches inférieures et des capteurs actuellement disponibles sur tous les appareils mobiles modernes. Au contraire, la plupart des techniques d’adaptation de débit reposent sur une estimation de ce dernier ou sur d’autres mesures disponibles à niveau application, telles que la quantité de données pré-chargées. Dans cette direction, nous proposons une nouvelle solution d’adaptation de débit basée sur le contexte et intégrant les informations des capteurs du téléphone. [2] Concerne les fournisseurs de services video OTT. La plupart des algorithmes d’adaptation de débit existants dépendent de modèles statistiques et se heurtent donc à des difficultés quand il est nécessaire de généraliser de manière appropriée ces modèles en dehors des scénarios prévus lors de la modélisation statistique.Nous proposons un nouvel algorithme d’adaptation du débit basé sur l’apprentissage en ligne, qui fonctionne bien sur un large éventail de scénarios de streaming. Cela ne nécessite aucun réglage de paramètre, aucune modification en fonction du type d’application ou des hypothèses statistiques pour le canal.[3] Concerne l’absence de jeux de données disponibles et actualisés pour le trafic du streaming vidéo mobile. Afin de mieux comprendre le trafic HAS et d’obtenir des données fiables qui permettraient aux opérateurs d’optimiser leurs réseaux, nous avons mené une vaste campagne expérimentale visant à collecter des informations sur plusieurs couches à partir du trafic en streaming. L’ensemble de données qui en résulte est mis à la disposition de la communauté académique et industrielle, les données étant enregistrées aux niveaux réseau, transport et application.Nous avons aussi enregistré les données du streaming vidéo sur QUIC. Enfin, nous avons utilisé ces données pour concevoir une nouvelle technique de profilage de trafic, basée sur l’apprentissage automatique, et qui fournit une estimation des paramètres du système HAS à partir de mesures ”passives” uniquementAs mobile networking technology is experiencing perpetual evolution and the computing capabilities of mobile devices are being constantly enhanced, the demand for bandwidth-intensive mobile multimedia consumption is currently experiencing an unprecedented surge. In 2017, mobile video streaming accounted for 58% of the global mobile data traffic, a percentage that is projected to reach a striking 79% by 2022. Most of this traffic is Video on Demand (VoD) over HTTP Adaptive Streaming (HAS), which undoubtedly becomes fast an integral part of the mobile client’s life. HAS solutions employ rate adaptation algorithms, that seamlessly adjust the rate of the media stream, to compensate for changing network conditions. Most notably, Dynamic Adaptive Streaming over HTTP (DASH) is a standard for HAS, that uses existing web server infrastructure and is now the dominant solution for video delivery. Nonetheless, video delivery over mobile networks still faces substantial challenges, primarily in mobile networks, that are commonly characterized by throughput variation; primarily attributed to physical effects associated with radio propagation, along with shortterm session interruptions attributed to user mobility. Depending on the current user location, channel degradation can have a detrimental impact on user Quality of Experience (QoE). The scope of this dissertation is to treat these challenges of video delivery in mobile networks and expedite its optimization, under two distinct perspectives. Under the perspective of Over the Top (OTT) video service providers, we propose new mobile rate adaptation algorithms; whereas, under the perspective of telecommunication equipment vendors and network service operators, we explore the merits of HAS traffic collection and its analysis, on network management. Upon conducting a performance evaluation of stateof- the-art HAS schemes, we have identified 3 open issues in the current state of HAS. The first issue concerns the type of input that drives the rate adaptation logic. Although several rate adaptation algorithms have been introduced in order to improve user QoE, only few leverage cross-layer and sensor information that is nowadays readily available in all modern mobile devices, while most rely on either throughput estimation or application-level readings, such as the amount of pre-fetched data. In that direction, we propose a new context-aware rate adaptation solution, that incorporates cellular sensor information into the rate adaptation process. The second open issue concerns OTT video service providers, who are continuously expanding their services to include more diverse user classes, network scenarios, and streaming applications. Most existing rate adaptation algorithms depend on statistical models for the unknowns and thus face complications at generalizing appropriately well beyond a certain scope of usage. To mitigate this limitation, we propose a novel rate adaptation algorithm based on online learning, that performs well over a wide spectrum of streaming scenarios due to its design principle; its ability to learn. It does so without requiring any parameter tuning, modifications according to application type or statistical assumptions for the channel. Last, the third open issue regards the absence of available data-sets for up-to-date mobile video streaming traffic. To better understand HAS traffic and also in order to obtain reliable data that would ultimately enable operators to optimize their networks, we conduct an extensive experimental campaign to collect crosslayer information from streaming traffic. The resulting data-set is made publicly available, with data recorded at the transport, network and application layer; capturing video streaming traffic over QUIC, for the first time. Additionally, we use this data-set to design a novel traffic profiling solution, based on machine learning, that estimates parameters of HAS applications from passive measurements
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Kim, Taehyun. "Scalable Video Streaming over the Internet". Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/6829.
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The objectives of this thesis are to investigate the challenges on video streaming, to explore and compare different video streaming mechanisms, and to develop video streaming algorithms that maximize visual quality. To achieve these objectives, we first investigate scalable video multicasting schemes by comparing layered video multicasting with replicated stream video multicasting. Even though it has been generally accepted that layered video multicasting is superior to replicated stream multicasting, this assumption is not based on a systematic and quantitative comparison. We argue that there are indeed scenarios where replicated stream multicasting is the preferred approach.
We also consider the problem of providing perceptually good quality of layered VBR video. This problem is challenging, because the dynamic behavior of the Internet's available bandwidth makes it difficult to provide good quality. Also a video encoded to provide a consistent quality exhibits significant data rate variability. We are, therefore, faced with the problem of accommodating the mismatch between the available bandwidth variability and the data rate variability of the encoded video. We propose an optimal quality adaptation algorithm that minimizes quality variation while at the same time increasing the utilization of the available bandwidth.
Finally, we investigate the transmission control protocol (TCP) for a transport layer protocol in streaming packetized media data. Our approach is to model a video streaming system and derive relationships under which the system employing the TCP protocol achieves desired performance. Both simulation results and the Internet experimental results validate this model and demonstrate the buffering delay requirements achieve desired video quality with high accuracy. Based on the relationships, we also develop realtime estimation algorithms of playout buffer requirements.
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Gurses, Eren. "Optimal Streaming Of Rate Adaptable Video". Phd thesis, METU, 2006. http://etd.lib.metu.edu.tr/upload/12607352/index.pdf.
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In this study, we study the dynamics of network adaptive video streaming and propose novel algorithms for rate distortion control in video streaming. While doing so, we maintain inter-protocol fairness with TCP (Transmission Control Protocol) that is the dominant transport protocol in the current Internet. The proposed algorithms are retransmission-based and necessitate the use of playback buffers in order to tolerate the extra latency introduced by retransmissions. In the first part, we propose a practical network-adaptive streaming scheme based on TCP transport and the idea of Selective Frame Discarding (SFD) that makes use of two-layer temporally scalable video. The efficacy of the SFD scheme is validated for playout buffer times in the order of seconds and therefore makes it suitable more for delay tolerant streaming applications.
In the second part of the thesis, we propose an application layer rate-distortion control algorithm which provides Optimal Scheduling and Rate Control (OSRC) policies in the average reward sense in order to achieve efficient streaming of video. The Optimal Scheduling (OS) we propose maximizes the probability of successfully on time delivery according to a prespecified set of rate constraints, and different channel conditions by using Markov Decision Process (MDP) models. On the other hand optimal rate control (RC) is achieved by calculating the optimal rate constraint which minimizes the average distortion of a video streaming session by making use of the video distortion model derived for lossy channels and achievable success probabilities provided by the set of optimal schedules. For numerical examples, we focus on an equation-based TCP friendly rate control (TFRC) protocol where transport layer retransmissions are disabled and Fine Granular Scalable (FGS) coded video is used for improved rate adaptation capabilities but with an additional rate distortion penalty. The efficacy of the proposed OSRC algorithm is demonstrated by means of both analytical results and ns-2 simulations.
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Afzaal, Qasim, e Usman Ahmad. "Audio Video Streaming Solution for Bambuser". Thesis, Umeå universitet, Institutionen för datavetenskap, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-58494.
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Audio/Video streaming has widely been used in different applications but the social communication applications have especially raised its usage. The aim of this thesis is to design and develop an improved Audio/Video streaming solution for a Swedish company Bambuser and can easily be extended with new features where necessary. Currently Bambuser is using the Flash Media Server (FMS) for streaming the media, but it is license based and adds the extra cost to the company's budget. It does not support a wide range of platforms (e.g. OpenBSD and various Linux distributions) and also has limited options for the streaming. There is no real time monitoring and controlling functionality, which can show the status of essential services to the user, needed for the streaming (for example if the camera is working, microphone is turned on, battery power status. etc.). In order to solve these issues the GStreamer is used, which is an Open source multimedia streaming framework. The GStreamer environment was tested on different Linux distributions. The research and implementation includes the creation of the streaming pipeline and analyzing which options (i.e. GStreamer elements and plugins) are required to stream the media. It also includes the testing of different pipeline parameters (for example video rate, audio rate etc.) and noting their effects in a real working environment. Python binding with GStreamer is used to have better control over the pipeline. Another requirement of this project was to add the functionality of monitoring and control that shows the status of essential services to the user. Implementation of this part is done by using server and client side coding. Further improvements and suggestions are also proposed in this report.
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Brandt, Jens. "Multidimensional transcoding for adaptive video streaming". Berlin Logos, 2009. http://d-nb.info/1000185028/04.
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Mao, Hongzi. "Neural adaptive video streaming with pensieve". Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/111926.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 55-59).
Client-side video players employ bitrate adaptation algorithms to cater to the ever-growing QoE requirements of users. These ABR algorithms must balance multiple QoE factors, such as maximizing video bitrate and minimizing rebuffering times. Despite the abundance of recently proposed ABR algorithms, state-of-the-art schemes suffer from two practical challenges: (1) throughput prediction is difficult and inaccurate predictions can lead to degraded performance; (2) existing algorithms use fixed heuristics which have been fine-tuned according to strict assumptions about deployment environments - such tuning precludes generalization across network conditions and QoE objectives. To overcome these challenges, we develop Pensieve, a system that generates ABR algorithms entirely using Reinforcement Learning (RL). Pensieve uses RL to train a neural network model that selects bitrates for future video chunks based on observations collected by client video players. Unlike existing approaches, Pensieve does not rely upon pre-programmed models or assumptions about the environment. Instead, it learns to make ABR decisions solely through observations of the resulting performance of past decisions. As a result, Pensieve can automatically learn ABR algorithms that adapt to a wide range of environmental conditions and QoE metrics. We compare Pensieve to state-of-the-art ABR algorithms using trace-driven and real world experiments spanning a wide variety of network conditions, QoE metrics, and video properties. In all considered scenarios, Pensieve outperforms the best stateof- the-art scheme, with improvements in average QoE of 13.1%-25.0%. Pensieve's policies generalize well, outperforming existing schemes even on networks on which it was not trained.
by Hongzi Mao.
S.M.
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Abe, Adewale. "High speed 802.11ad wireless video streaming". Thesis, University of Essex, 2018. http://repository.essex.ac.uk/22352/.
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The aim of this thesis is to investigate, both theoretically and experimentally, the capability of the IEEE 802.11ad device, the Wireless Gigabit Alliance known as WiGig operating in the 60 GHz band to handle rise in data traffic ubiquitous to high speed data transmission such as bulk data transfer, and wireless video streaming. According to Cisco and others, it is estimated that in 2020, internet video traffic will account for 82 % of all consumer internet traffic. This research evalu- ated the feasibility of the 60 GHz to provide minimum data rate of about 970 Mbps from the Ethernet link limited or clamped to 1 Gbps. This translated to 97 % effi- ciency with respect to the IEEE 802.11ad system performance. For the first time, the author proposed the enhancement of millimetre wave propagation through the use of specular reflection in non-line-of-sight environment, providing at least 94 % bandwidth utilization. Additional investigations result of the IEEE 802.11ad device in real live streaming of 4k ultra-high definition (UHD) video shows the feasibility of aggressive frequency reuse in the absence of co-channel interference. Moreover, using heuristic approach, this work compared materials absorption and signal reception at 60 GHz and the results gives better performance in contrast to the theoretical values. Finally, this thesis proposes a framework for the 802.11ad wireless H.264 video streaming over 60 GHz band. The work describes the potential and efficiency of WiGig device in streaming high definition (HD) video with high temporal index (TI) and 4k UHD video with no retransmission. Caching point established at the re-transmitter increase coverage and cache multimedia data. The results in this thesis shows the growing potential of millimeter wave technology, the WiGig for very high speed bulk data transfer, and live streaming video transmission.
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Altamimi, Sadi. "QoE-Fair Video Streaming over DASH". Thesis, Université d'Ottawa / University of Ottawa, 2018. http://hdl.handle.net/10393/38591.
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Video streaming has become, and is expected to remain, the dominant type of traffic over the Internet. With this high demand for multimedia streaming, there is always a question on how to provide acceptable and fair Quality of Experience (QoE) for consumers of the over-the-top video services, despite the best-effort nature of the Internet and the limited network resources, shared by concurrent users. MPEG-DASH, as one of the most widely used standards of HTTP-based adaptive streaming, uses a client-side rate adaptation algorithms; which is known to suffer from two practical challenges: in one hand, clients use fixed heuristics that have been fine-tuned according to strict assumptions about deployment environments which limit its ability to generalize across network conditions. On the other hand, the absence of collaboration among DASH clients leads to unfair bandwidth allocation, and typically ends up in an unbalanced equilibrium point. We believe that augmenting a server-side rate adaptation significantly improves the fairness of network bandwidth allocation among concurrent users. We have formulated the problem as a Decentralized Partially Observable Markov Decision Process (Dec-POMDP) model, and used RL to train two neural networks to find an optimal solution to the proposed Dec-POMDP problem in a distributed way. We showed that our proposed client-server collaboration outperforms the state-of-the-art schemes in terms of QoE-efficiency, QoE-fairness, and social welfare by as much as 16%, 21%, and 24% respectively.
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SANTOS, Gustavo Gentil Barreto. "Video streaming optimization in ADSL architecture". Universidade Federal de Pernambuco, 2007. https://repositorio.ufpe.br/handle/123456789/2712.
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Previous issue date: 2007Com a evolução do mercado de banda larga e a diminuição dos serviços de telefonia tradicionais, os provedores de serviço de telefonia têm a necessidade de oferecer uma grande gama de serviços para se manter competitivo e obter novas fatias do mercado. Novos serviços de áudio e vídeo podem ser oferecidos como nunca antes. Com a junção de serviços de voz, dados e vídeo, serviços Triple Play (3P) são essenciais para que as operadoras e provedores de serviço mantenham sua base seus usuários atuais. O oferecimento de serviços IPTV usando conexões DSL é uma tecnologia emergente que traz novas oportunidades de negócios para os provedores de serviços. Tecnologias de banda larga como o ADSL2+ possuem taxas de dados que tornam possível combinar serviços de voz, vídeo e dados utilizando uma única linha telefônica. Levando em consideração essas melhorias tecnológicas, o padrão ADSL2+ consegue obter taxas de 24 Mbps na teoria, o que seria o suficiente para oferecer alguns canais SDTV (1.5~4 Mbps dependendo do codec utilizado) e HDTV (8~12 Mbps dependendo do codec utilizado) para o usuário residencial. Entretanto outros fatores como ruídos e a distancia entre o usuário e o provedor de serviços pode tornar esse cenário impraticável. Na maioria das vezes o provedor de serviços de vídeo codifica o sinal utilizando o MPEG-2 ou MPEG-4. Aplicações de vídeo em rede requerem transferência de dados ininterrupta, pois a perda de poucos pacotes pode resultar em uma grande perda de qualidade do vídeo. Perda de pacotes pode ser causada de duas maneiras distintas. Por ruídos, que podem ser encontrados em qualquer ambiente de transmissão e podem gerar um efeito indesejável, introduzindo mais erros que o esperado durante a transmissão, ou por estouro do buffer em diferentes elementos da rede. Além do mais, em determinados cenários, a influência do delay e do jitter pode ser crucial na entrega do vídeo para o usuário. Este trabalho aborda os problemas presentes na transmissão de vídeo numa infra-estrutura ADSL, ilustrando diferentes cenários, tais como ambientes com ruído, com tráfego concorrente e diferentes distancias entre o usuário e a provedora de serviço. Variáveis relacionadas à infra-estrutura ADSL, como, por exemplo, proteção a ruído e mecanismos de QoS são observados e ajustes são realizados na intenção de oferecer ao usuário final uma melhoria na qualidade do vídeo. Parâmetros relacionados as Camada 1, 2 e 3 e a nível de aplicação são estudados e analisados. Além disso, diferentes tipos de ruídos na transmissão, tal como REIN, serão inseridos no intuito de simular problemas existentes em um cenário real. Os resultados gerados pelos experimentos mostram que para diferentes tipos de problemas agregados a linha, existem muitos fatores, tais como INP, SNR, Interleaving Delay, que podem ser ajustados visando a melhoria da qualidade do vídeo. No final deste trabalho é apresentada uma configuração desejável para sistemas ADSL no processo de transmissão de vídeo visando minimizar os problemas existentes na linha
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Nutalapati, Hima Bindu. "Sustainable Throughput Measurements for Video Streaming". Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-14003.
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With the increase in demand for video streaming services on the hand held mobile terminals with limited battery life, it is important to maintain the user Quality of Experience (QoE) while taking the resource consumption into consideration. Hence, the goal is to offer as good quality as feasible, avoiding as much user-annoyance as possible. Hence, it is essential to deliver the video, avoiding any uncontrollable quality distortions. This can be possible when an optimal (or desirable) throughput value is chosen such that exceeding the particular threshold results in entering a region of unstable QoE, which is not feasible. Hence, the concept of QoE-aware sustainable throughput is introduced as the maximal value of the desirable throughput that avoids disturbances in the Quality of Experience (QoE) due to delivery issues, or keeps them at an acceptable minimum. The thesis aims at measuring the sustainable throughput values when video streams of different resolutions are streamed from the server to a mobile client over wireless links, in the presence of network disturbances packet loss and delay. The video streams are collected at the client side for quality assessment and the maximal throughput at which the QoE problems can still be kept at a desired level is determined. Scatter plots were generated for the individual opinion scores and their corresponding throughput values for the disturbance case and regression analysis is performed to find the best fit for the observed data. Logarithmic, exponential, linear and power regressions were considered in this thesis. The R-squared values are calculated for each regression model and the model with R-squared value closest to 1 is determined to be the best fit. Power regression model and logarithmic model have the R-squared values closest to 1. Better quality ratings have been observed for the low resolution videos in the presence of packet loss and delay for the considered test cases. It can be observed that the QoE disturbances can be kept at a desirable level for the low resolution videos and from the test cases considered for the investigation, 360px video is more resilient in case of high delay and packet loss values and has better opinion score values. Hence, it can be observed that the throughput is sustainable at this threshold.
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Haywood, Richard James. "H.264 Data Partitioned Video Streaming". Thesis, Aston University, 2009. http://publications.aston.ac.uk/15320/.
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Motivated by the increasing demand and challenges of video streaming in this thesis, we investigate methods by which the quality of the video can be improved. We utilise overlay networks that have been created by implemented relay nodes to produce path diversity, and show through analytical and simulation models for which environments path diversity can improve the packet loss probability. We take the simulation and analytical models further by implementing a real overlay network on top of Planetlab, and show that when the network conditions remain constant the video quality received by the client can be improved. In addition, we show that in the environments where path diversity improves the video quality forward error correction can be used to further enhance the quality. We then investigate the effect of IEEE 802.11e Wireless LAN standard with quality of service enabled on the video quality received by a wireless client. We find that assigning all the video to a single class outperforms a cross class assignment scheme proposed by other researchers. The issue of virtual contention at the access point is also examined. We increase the intelligence of our relay nodes and enable them to cache video, in order to maximise the usefulness of these caches. For this purpose, we introduce a measure, called the PSNR profit, and present an optimal caching method for achieving the maximum PSNR profit at the relay nodes where partitioned video contents are stored and provide an enhanced quality for the client. We also show that the optimised cache the degradation in the video quality received by the client becomes more graceful than the non-optimised system when the network experiences packet loss or is congested.
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Balhaj, Mohamed. "Characterizing Latencies of Edge Video Streaming". Thesis, The University of North Carolina at Charlotte, 2017. http://pqdtopen.proquest.com/#viewpdf?dispub=10280746.
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The use of video streaming has been growing rapidly in the recent years and has been utilized in various applications. Many of these applications are latency sensitive, but the latency requirements varies largely from one application to another. The high quality videos captured by cameras are quite large in size, so they are encoded to reduce the video size to achieve a reasonable bandwidth when sent over a network.
In this work, we characterize the latency components of edge video streaming with the goal of identifying latency bottlenecks. In edge applications, the processing is performed at the edge of the network close to data generation, rather than in the cloud, to meet the latency requirements. This work specifically investigates the latencies in the transmit and receive paths in the Linux networking stack, and the impact of encoding parameters on the latency.
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Tripathi, Avanish. "Adaptive content-aware scaling for improved video streaming". Link to electronic thesis, 2001. http://www.wpi.edu/Pubs/ETD/Available/etd-0501101-142625.
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Bruneau-Queyreix, Joachim. "Multi-Criteria Optimization of Content Delivery within the Future Media Internet". Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0745/document.
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Les solutions de streaming vidéo adaptatives basées sur l’utilisation du protocol HTTP ont été largement plébiscitées dans les mondes de l’industrie et de la recherche, notamment pour les possibilités d’améliorations de qualité d’experience qu’elles offrent ainsi que pour leurs facilités de déploiement liées au protocol HTTP. Pour autant, bien que ces solutions permettent d’augmenter la qualité d’experience utilisateurs en diminuant la qualité de la vidéo transmise sur les réseaux pour minimiser les interruptions vidéo liées au temps de chargement, la qualité intrinsèque de la vidéo est limitée par les capacités physiques du chemin entre le serveur utilisé et le client. Dans l’objectif d’augmenter la qualité d’experience utilisateurs et de diminuer les couts de déploiements des services de streaming, les travaux de cette thèse de doctorat proposent de faire évoluer de façon pragmatique les solutions de streaming adaptatives actuelles vers l’utilisation en simultané de plusieurs sources (serveurs ou pairs). La première contribution de cette thèse présente MS-Stream, une technique évolutive de streaming adaptatif basé sur HTTP et utilisant plusieurs serveurs simultanément. MS-Stream offre la possibilité d’exploiter la bande passante disponible dans les infrastructures distribuées et les réseaux hétérogènes. La deuxieme contribution de ce document est MATHIAS, un groupe d’algorithmes d’adaptation centrés client, implémentés dans MS-Stream, qui a pour vocation d’optimiser l’utilisation des ressources réseau hétérogènes mises à disposition du client pour obtenir une qualité vidéo cible. MATHIAS permet à chaque client de controller le nombre de serveur utilisé en simultané, de faire face à l’hétérogeneité des resources disponibles, de réagir aux fluctuations soudaines et non-anticipées des capacités des serveurs tout en donnant à l’utilisateur une experience de streaming ininterrompu. Pour finir, nous allons plus loin dans les capacités de scalabilité et de qualité d’experience de MS-Stream et MATHIAS en tirant profit des ressources physiques des consommateurs. Nous proposons une solution hybride pair-à-pair/multi-server de streaming adaptative: PMS. Au sein de PMS, les logiques d’adaptation de la qualité vidéo et de la scalabilité sont distribuées pour permettre à chaque client de tendre vers une utilisation optimale de l’infrastructure de streamingSingle-source HTTP Adaptive Streaming solutions (HAS) have become the de-facto solutions to deliver video over the Internet mostly due to their capabilities to increase end-user’s Quality of Experience (QoE) as well as their ease of deployment due to the usage of the HTTP protocol. Although HAS solutions can increase QoE by trading off the delivered video quality to minimize the number of video freezing events, they are limited by the bandwidth available on the considered communication channel between the client and the server. This thesis exposes our contributions in building lightweight pragmatic and evolving solutions advocating for the simultaneous usage of multiple sources with heterogeneous capacities so as to achieve high QoE content delivery at low cost. The first contribution of this work presents a streaming solution extending HAS capabilities to a pragmatic multi-server technique: MS-Stream. MS-Stream provides the means to exploit expanded bandwidth and link diversity in distributed heterogeneous network infrastructures. In our second contribution, we propose MATHIAS, a client-side two-phase consumption and adaptation algorithm implemented into MSStream. MATHIAS aims at increasing the end-user’s perceived streaming quality while utilizing the most of the heterogeneous capacities offered at the service and network environments. Finally, we further extend the QoE and scalability capabilities of MS-Stream and MATHIAS by leveraging on clients’ connectivity capacities and we expose our third contribution: a hybrid P2P/Multi-server live-Streaming system (PMS) incorporating distributed quality and scalability adaptation mechanisms
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Chebudie, Abiy Biru. "Monitoring of Video Streaming Quality from Encrypted Network Traffic : The Case of YouTube Streaming". Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-13336.
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The video streaming applications contribute to a major share of the Internet traffic. Consequently, monitoring and management of video streaming quality has gained a significant importance in the recent years. The disturbances in the video, such as, amount of buffering and bitrate adaptations affect user Quality of Experience (QoE). Network operators usually monitor such events from network traffic with the help of Deep Packet Inspection (DPI). However, it is becoming difficult to monitor such events due to the traffic encryption. To address this challenge, this thesis work makes two key contributions. First, it presents a test-bed, which performs automated video streaming tests under controlled time-varying network conditions and measures performance at network and application level. Second, it develops and evaluates machine learning models for the detection of video buffering and bitrate adaptation events, which rely on the information extracted from packets headers. The findings of this work suggest that buffering and bitrate adaptation events within 60 second intervals can be detected using Random Forest model with an accuracy of about 70%. Moreover, the results show that the features based on time-varying patterns of downlink throughput and packet inter-arrival times play a distinctive role in the detection of such events.
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Pranke, Nico. "Skalierbares und flexibles Live-Video Streaming mit der Media Internet Streaming Toolbox". Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2010. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-26652.
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Die Arbeit befasst sich mit der Entwicklung und Anwendung verschiedener Konzepte und Algorithmen zum skalierbaren Live-Streaming von Video sowie deren Umsetzung in der Media Internet Streaming Toolbox. Die Toolbox stellt eine erweiterbare, plattformunabhängige Infrastruktur zur Erstellung aller Teile eines Live-Streamingsystems von der Videogewinnung über die Medienverarbeitung und Codierung bis zum Versand bereit. Im Vordergrund steht die flexible Beschreibung der Medienverarbeitung und Stromerstellung sowie die Erzeugung von klientenindividuellen Stromformaten mit unterschiedlicher Dienstegüte für eine möglichst große Zahl von Klienten und deren Verteilung über das Internet. Es wird ein integriertes graphenbasiertes Konzept entworfen, in dem das Component Encoding Stream Construction, die Verwendung von Compresslets und eine automatisierte Flussgraphenkonstruktion miteinander verknüpft werden. Die für die Stromkonstruktion relevanten Teile des Flussgraphen werden für Gruppen mit identischem Zustand entkoppelt vom Rest ausgeführt. Dies führt zu einer maximalen Rechenlast, die unabhängig von der Zahl der Klienten ist, was sowohl theoretisch gezeigt als auch durch konkrete Messungen bestätigt wird. Als Beispiele für die Verwendung der Toolbox werden unter Anderem zwei waveletbasierte Stromformate entwickelt, integriert und bezüglich Codiereffizienz und Skalierbarkeit miteinander verglichen
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Pranke, Nico. "Skalierbares und flexibles Live-Video Streaming mit der Media Internet Streaming Toolbox". Doctoral thesis, TU Bergakademie Freiberg, 2009. https://tubaf.qucosa.de/id/qucosa%3A22696.
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Die Arbeit befasst sich mit der Entwicklung und Anwendung verschiedener Konzepte und Algorithmen zum skalierbaren Live-Streaming von Video sowie deren Umsetzung in der Media Internet Streaming Toolbox. Die Toolbox stellt eine erweiterbare, plattformunabhängige Infrastruktur zur Erstellung aller Teile eines Live-Streamingsystems von der Videogewinnung über die Medienverarbeitung und Codierung bis zum Versand bereit. Im Vordergrund steht die flexible Beschreibung der Medienverarbeitung und Stromerstellung sowie die Erzeugung von klientenindividuellen Stromformaten mit unterschiedlicher Dienstegüte für eine möglichst große Zahl von Klienten und deren Verteilung über das Internet. Es wird ein integriertes graphenbasiertes Konzept entworfen, in dem das Component Encoding Stream Construction, die Verwendung von Compresslets und eine automatisierte Flussgraphenkonstruktion miteinander verknüpft werden. Die für die Stromkonstruktion relevanten Teile des Flussgraphen werden für Gruppen mit identischem Zustand entkoppelt vom Rest ausgeführt. Dies führt zu einer maximalen Rechenlast, die unabhängig von der Zahl der Klienten ist, was sowohl theoretisch gezeigt als auch durch konkrete Messungen bestätigt wird. Als Beispiele für die Verwendung der Toolbox werden unter Anderem zwei waveletbasierte Stromformate entwickelt, integriert und bezüglich Codiereffizienz und Skalierbarkeit miteinander verglichen
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Ye, Zakaria. "Analyse de Performance des Services de Vidéo Streaming Adaptatif dans les Réseaux Mobiles". Thesis, Avignon, 2017. http://www.theses.fr/2017AVIG0219/document.
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Le trafic vidéo a subi une augmentation fulgurante sur Internet ces dernières années. Pour pallier à cette importante demande de contenu vidéo, la technologie du streaming adaptatif sur HTTP est utilisée. Elle est devenue par ailleurs très populaire car elle a été adoptée par les différents acteurs du domaine de la vidéo streaming. C’est une technologie moins couteuse qui permet aux fournisseurs de contenu, la réutilisation des serveurs web et des caches déjà déployés. En plus, elle est exempt de tout blocage car elle traverse facilement les pare-feux et les translations d’adresses sur Internet. Dans cette thèse, nous proposons une nouvelle méthode de vidéo streaming adaptatif appelé “Backward-Shifted Coding (BSC)”. Il se veut être une solution complémentaire au standard DASH, le streaming adaptatif et dynamique utilisant le protocole HTTP. Nous allons d’abord décrire ce qu’est la technologie BSC qui se base sur le codec (encodeur décodeur) à multi couches SVC, un algorithme de compression extensible ou évolutif. Nous détaillons aussi l’implémentation de BSC dans un environnement DASH. Ensuite,nous réalisons une évaluation analytique de BSC en utilisant des résultats standards de la théorie des files d’attente. Les résultats de cette analyse mathématique montrent que le protocole BSC permet de réduire considérablement le risque d’interruption de la vidéo pendant la lecture, ce dernier étant très pénalisant pour les utilisateurs. Ces résultats vont nous permettre de concevoir des algorithmes d’adaptation de qualité à la bande passante en vue d’améliorer l’expérience utilisateur. Ces algorithmes permettent d’améliorer la qualité de la vidéo même étant dans un environnement où le débit utilisateur est très instable.La dernière étape de la thèse consiste à la conception de stratégies de caching pour optimiser la transmission de contenu vidéo utilisant le codec SVC. En effet, dans le réseau, des serveurs de cache sont déployés dans le but de rapprocher le contenu vidéo auprès des utilisateurs pour réduire les délais de transmission et améliorer la qualité de la vidéo. Nous utilisons la programmation linéaire pour obtenir la solution optimale de caching afin de le comparer avec nos algorithmes proposés. Nous montrons que ces algorithmes augmentent la performance du système tout en permettant de décharger les liens de transmission du réseau cœurDue to the growth of video traffic over the Internet in recent years, HTTP AdaptiveStreaming (HAS) solution becomes the most popular streaming technology because ithas been succesfully adopted by the different actors in Internet video ecosystem. Itallows the service providers to use traditional stateless web servers and mobile edgecaches for streaming videos. Further, it allows users to access media content frombehind Firewalls and NATs.In this thesis we focus on the design of a novel video streaming delivery solutioncalled Backward-Shifted Coding (BSC), a complementary solution to Dynamic AdaptiveStreaming over HTTP (DASH), the standard version of HAS. We first describe theBackward-Shifted Coding scheme architecture based on the multi-layer Scalable VideoCoding (SVC). We also discuss the implementation of BSC protocol in DASH environment.Then, we perform the analytical evaluation of the Backward-Sihifted Codingusing results from queueing theory. The analytical results show that BSC considerablydecreases the video playback interruption which is the worst event that users can experienceduring the video session. Therefore, we design bitrate adaptation algorithms inorder to enhance the Quality of Experience (QoE) of the users in DASH/BSC system.The results of the proposed adaptation algorithms show that the flexibility of BSC allowsus to improve both the video quality and the variations of the quality during thestreaming session.Finally, we propose new caching policies to be used with video contents encodedusing SVC. Indeed, in DASH/BSC system, cache servers are deployed to make contentsclosed to the users in order to reduce network latency and improve user-perceived experience.We use Linear Programming to obtain optimal static cache composition tocompare with the results of our proposed algorithms. We show that these algorithmsincrease the system overall hit ratio and offload the backhaul links by decreasing thefetched content from the origin web servers
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Ojanperä, T. (Tiia). "Cross-layer optimized video streaming in heterogeneous wireless networks". Doctoral thesis, Oulun yliopisto, 2013. http://urn.fi/urn:isbn:9789526201511.
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Abstract This dissertation studies the impact of heterogeneous wireless networks on the design and implementation of mobile video streaming services. The aim is to enable Quality of Service (QoS) sensitive video streaming services to take full advantage of the access diversity of heterogeneous networks in order to optimize their operation in terms of quality and efficiency of network resource usage. This nevertheless requires support beyond the layered communication architecture of today’s Internet. The thesis proposes an architecture for end-to-end cross-layer signaling and control for video streaming systems. The architecture supports extensive context informa- tion transfer in heterogeneous networks; thus, enabling the efficient management of video stream adaptation and user terminal mobility in a diverse and dynamic network environment. This thesis also studies and proposes cross-layer enhancements for adaptive video streaming and mobility management functions enabled by the cross- layer architecture. These include cross-layer video adaptation, congestion-triggered handovers, and concurrent utilization of multiple access networks in the video stream transport. For the video adaptation and multipath transmission, the flexible adaptation and transmission capabilities of the novel scalable video coding technology are used. Regarding the mobility management, the proposed solutions essentially enhance the handover decision-making of the Mobile IP protocol to better support QoS-sensitive video streaming. Finally, the thesis takes a holistic view on the application adaptation and mobility management, and proposes a solution for coordinated control of these two operations in order to achieve end-to-end optimization. The resulting mobile video streaming system architecture and the cross-layer control algorithms are evaluated using network simulations and real prototypes. Based on the results, the proposed mechanisms can be seen to be viable solutions for improving video streaming performance in heterogeneous wireless networks. They require changes in the communication end-points and the access network but support gradual deployment. This allows service providers and operators to select only a subset of the proposed mechanisms for implementation. The results also support the need for cross-layer signaling and control in facilitating efficient management and utilization of heterogeneous wireless networksTiivistelmä Väitöskirja tutkii langattomien ja heterogeenisen verkkoympäristöjen vaikutusta erityisesti mobiilikäyttöön suunnattuihin suoratoistovideopalveluihin (streaming). Työn tavoitteena on löytää keino optimoida verkkoyhteyden palvelunlaadulle (QoS) herkän suoratoistovideon toiminta sekä videopalvelun laadun että verkon tiedonsiirtokapasiteetin käytön osalta. Tämä tapahtuu mahdollistamalla heterogeenisten verkkojen tehokas käyttö suoratoistovideopalvelujen tapauksessa. Tavoitellut parannukset vaativat kuitenkin muutoksia nykyiseen kerroksittaiseen Internet-arkkitehtuuriin. Väitöskirjassa esitetään arkkitehtuuri protokollakerrosten välisen tiedon (cross-layer) välitykseen ja hyödyntämiseen suoratoistovideopalvelujen tiedonsiirron kontrolloinnissa. Arkkitehtuuria voidaan käyttää laaja-alaiseen kontekstitiedon välitykseen tietoverkoissa, mikä mahdollistaa tehokkaan videopalvelun adaptoinnin ja päätelaitteen liikkuvuudenhallinnan heterogeenisissa verkoissa, joissa palvelunlaatu vaihtelee. Väitöskirja myös ehdottaa erilaisia ratkaisuja videopalvelun adaptoinnin ja tiedonsiirron parantamiseksi arkkitehtuuria hyödyntämällä. Näihin lukeutuvat usealle protokollakerrokselle toteutettu videon adaptointi, verkkoyhteyden ruuhkautumiseen reagoiva yhteydensiirto sekä usean verkkoyhteyden samanaikainen käyttö videopalvelun tiedonsiirrossa. Videon adaptoinnissa ja siirrossa hyödynnetään uutta skaalautuvaa videonkoodausteknologiaa, joka mahdollistaa vaaditun, joustavan videobittivirran muokkauksen. Liikkuvuudenhallinnan osalta työssä keskitytään pääosin kehittämään Mobile IP -protokollan päätöksentekoa suoratoistovideopalvelujen tapauksessa. Lopuksi väitöskirjassa esitetään kokonaisvaltainen ja koordinoitu ratkaisu videopalvelun adaptoinnin sekä päätelaitteen liikkuvuuden hallintaan päästä päähän -optimoinnin saavuttamiseksi. Tuloksena esitetyt järjestelmäarkkitehtuuri ja protokollakerrosten välistä tietoa käyttävät hallinta-algoritmit evaluoitiin simulaatioiden ja oikeiden prototyyppien avulla. Tulokset osoittavat, että ehdotettuja menetelmiä voidaan käyttää parantamaan suoratoistovideopalvelujen suorituskykyä heterogeenisissa verkoissa. Ratkaisut vaativat muutoksia verkko- ja palveluarkkitehtuureihin, mutta niiden asteittainen tai osittainen käyttöönotto on mahdollista. Tulokset osoittavat myös protokollakerrosten välisen tiedon tarpeellisuuden langattomien ja heterogeenisten verkkojen tehokkaassa käytössä
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Aksay, Anil. "Error Resilient Multiview Video Coding And Streaming". Phd thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/12611682/index.pdf.
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In this thesis, a number of novel techniques for error resilient coding and streaming for multiview video are presented. First of all, a novel coding technique for stereoscopic video is proposed where additional coding gain is achieved by downsampling one of the views spatially or temporally based on the well-known theory that the human visual system can perceive high frequencies in 3D from the higher quality view. Stereoscopic videos can be coded at a rate upto 1.2 times that of monoscopic videos with little visual quality degradation with the proposed coding technique. Next, a systematic method for design and optimization of multi-threaded multi-view video encoding/decoding algorithms using multi-core processors is proposed. The proposed multi-core decoding architectures are compliant with the current international standards, and enable multi-threaded processing with negligible loss of encoding efficiency and minimum processing overhead. End-to-end 3D Streaming system over Internet using current standards is implemented. A heuristic methodology for modeling the end-toend rate-distortion characteristic of this system is suggested and the parameters of the system is optimally selected using this model. End-to-end 3D Broadcasting system over DVB-H using current standards is also implemented. Extensive testing is employed to show the importance and characteristics of several error resilient tools. Finally we modeled end-to-end RD characteristics to optimize the encoding and protection parameters.
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Kim, Joohee. "Error-resilient video streaming over lossy channels". Diss., Georgia Institute of Technology, 2003. http://hdl.handle.net/1853/13723.
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Addis, Antonio. "Deep reinforcement learning optimization of video streaming". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Questa tesi si occuperà dell'ottimizzazione delle performance di streaming video attraverso internet, divenute particolarmente problematiche con l'avvento delle nuove risoluzioni ultraHD e i video a 360 gradi per la realtà virtuale. Verranno confrontate le performance ottenute con gli algoritmi che attualmente fanno parte dello stato dell'arte, e sviluppato un modello di reinforcement learning che sia capace di effettuare scelte per migliorare la QoE(quality of experience) durante una sessione di streaming.
Per i video a 360 gradi, verrà inoltre implementata la tecnica snapchange, con questo metodo è possibile ridurre la banda utilizzata durante lo streaming, forzando la riposizione dello sguardo dell'utente in un'area di maggior interesse del video.
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Dimopoulos, Georgios. "Identifying and diagnosing video streaming performance issues". Doctoral thesis, Universitat Politècnica de Catalunya, 2018. http://hdl.handle.net/10803/461633.
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On-line video streaming is an ever evolving ecosystem of services and technologies, where content providers are on a constant race to satisfy the users' demand for richer content and higher bitrate streams, updated set of features and cross-platform compatibility. At the same time, network operators are required to ensure that the requested video streams are delivered through the network with a satisfactory quality in accordance with the existing Service Level Agreements (SLA).
However, tracking and maintaining satisfactory video Quality of Experience (QoE) has become a greater challenge for operators than ever before. With the growing popularity of content engagement on handheld devices and over wireless connections, new points-of-failure have added to the list of failures that can affect the video quality. Moreover, the adoption of end-to-end encryption by major streaming services has rendered previously used QoE diagnosis methods obsolete.
In this thesis, we identify the current challenges in identifying and diagnosing video streaming issues and we propose novel approaches in order to address them. More specifically, the thesis initially presents methods and tools to identify a wide array of QoE problems and the severity with which they affect the users' experience. The next part of the thesis deals with the investigation of methods to locate under-performing parts of the network that lead to drop of the delivered quality of a service.
In this context, we propose a data-driven methodology for detecting the under performing areas of cellular network with sub-optimal Quality of Service (QoS) and video QoE. Moreover, we develop and evaluate a multi-vantage point framework that is capable of diagnosing the underlying faults that cause the disruption of the user's experience. The last part of this work, further explores the detection of network performance anomalies and introduces a novel method for detecting such issues using contextual information. This approach provides higher accuracy when detecting network faults in the presence of high variation and can benefit providers to perform early detection of anomalies before they result in QoE issues.La distribución de vídeo online es un ecosistema de servicios y tecnologías, donde los proveedores de contenidos se encuentran en una carrera continua para satisfacer las demandas crecientes de los usuarios de más riqueza de contenido, velocidad de transmisión, funcionalidad y compatibilidad entre diferentes plataformas. Asimismo, los operadores de red deben asegurar que los contenidos demandados son entregados a través de la red con una calidad satisfactoria según los acuerdos existentes de nivel de servicio (en inglés Service Level Agreement o SLA). Sin embargo, la monitorización y el mantenimiento de un nivel satisfactorio de la calidad de experiencia (en inglés Quality of Experience o QoE) del vídeo online se ha convertido en un reto mayor que nunca para los operadores. Dada la creciente popularidad del consumo de contenido con dispositivos móviles y a través de redes inalámbricas, han aparecido nuevos puntos de fallo que se han añadido a la lista de problemas que pueden afectar a la calidad del vídeo transmitido. Adicionalmente, la adopción de sistemas de encriptación extremo a extremo, por parte de los servicios más importantes de distribución de vídeo online, ha dejado obsoletos los métodos existentes de diagnóstico de la QoE. En esta tesis se identifican los retos actuales en la identificación y diagnóstico de los problemas de transmisión de vídeo online, y se proponen nuevas soluciones para abordar estos problemas. Más concretamente, inicialmente la tesis presenta métodos y herramientas para identificar un conjunto amplio de problemas de QoE y la severidad con los que estos afectan a la experiencia de los usuarios. La siguiente parte de la tesis investiga métodos para localizar partes de la red con un rendimiento bajo que resultan en una disminución de la calidad del servicio ofrecido. En este contexto, se propone una metodología basada en el análisis de datos para detectar áreas de la red móvil que ofrecen un nivel subóptimo de calidad de servicio (en inglés Quality of Service o QoS) y QoE. Además, se desarrolla y se evalúa una solución basada en múltiples puntos de medida que es capaz de diagnosticar los problemas subyacentes que causan la alteración de la experiencia de usuario. La última parte de este trabajo explora adicionalmente la detección de anomalías de rendimiento de la red y presenta un nuevo método para detectar estas situaciones utilizando información contextual. Este enfoque proporciona una mayor precisión en la detección de fallos de la red en presencia de alta variabilidad y puede ayudar a los proveedores a la detección precoz de anomalías antes de que se conviertan en problemas de QoE.
La distribució de vídeo online és un ecosistema de serveis i tecnologies, on els proveïdors de continguts es troben en una cursa continua per satisfer les demandes creixents del usuaris de més riquesa de contingut, velocitat de transmissió, funcionalitat i compatibilitat entre diferents plataformes. A la vegada, els operadors de xarxa han d’assegurar que els continguts demandats són entregats a través de la xarxa amb una qualitat satisfactòria segons els acords existents de nivell de servei (en anglès Service Level Agreement o SLA). Tanmateix, el monitoratge i el manteniment d’un nivell satisfactori de la qualitat d’experiència (en anglès Quality of Experience o QoE) del vídeo online ha esdevingut un repte més gran que mai per als operadors. Donada la creixent popularitat del consum de contingut amb dispositius mòbils i a través de xarxes sense fils, han aparegut nous punts de fallada que s’han afegit a la llista de problemes que poden afectar a la qualitat del vídeo transmès. Addicionalment, l’adopció de sistemes d’encriptació extrem a extrem, per part dels serveis més importants de distribució de vídeo online, ha deixat obsolets els mètodes existents de diagnòstic de la QoE. En aquesta tesi s’identifiquen els reptes actuals en la identificació i diagnòstic dels problemes de transmissió de vídeo online, i es proposen noves solucions per abordar aquests problemes. Més concretament, inicialment la tesi presenta mètodes i eines per identificar un conjunt ampli de problemes de QoE i la severitat amb la que aquests afecten a la experiència dels usuaris. La següent part de la tesi investiga mètodes per localitzar parts de la xarxa amb un rendiment baix que resulten en una disminució de la qualitat del servei ofert. En aquest context es proposa una metodologia basada en l’anàlisi de dades per detectar àrees de la xarxa mòbil que ofereixen un nivell subòptim de qualitat de servei (en anglès Quality of Service o QoS) i QoE. A més, es desenvolupa i s’avalua una solució basada en múltiples punts de mesura que és capaç de diagnosticar els problemes subjacents que causen l’alteració de l’experiència d’usuari. L’última part d’aquest treball explora addicionalment la detecció d’anomalies de rendiment de la xarxa i presenta un nou mètode per detectar aquestes situacions utilitzant informació contextual. Aquest enfoc proporciona una major precisió en la detecció de fallades de la xarxa en presencia d’alta variabilitat i pot ajudar als proveïdors a la detecció precoç d’anomalies abans de que es converteixin en problemes de QoE.
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Su, Guan-Ming. "Dynamic resource allocation for multiuser video streaming". College Park, Md. : University of Maryland, 2006. http://hdl.handle.net/1903/3982.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2006.Thesis research directed by: Electrical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Österberg, Patrik. "Efficient multicast video streaming over heterogeneous networks /". Stockholm : KTH Microelectronics and Information Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-510.
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Alhaisoni, Majed Mohaia. "Video streaming using peer-to-peer networks". Thesis, University of Essex, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.528853.
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Shahbazian, John N. "Characterization and Generation of Streaming Video Traces". [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000160.
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Kritzner, Jan. "Tunable video streaming for wireless access networks". Aachen Shaker, 2009. http://d-nb.info/999465554/04.
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Lee, Yen-Chi. "Error resilient video streaming over lossy networks". Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04082004-180302/unrestricted/lee%5fyen-chi%5f200312%5fphd.pdf.
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Muzaffar, Raheeb. "Routing and video streaming in drone networks". Thesis, Queen Mary, University of London, 2017. http://qmro.qmul.ac.uk/xmlui/handle/123456789/24713.
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Drones can be used for several civil applications including search and rescue, coverage, and aerial imaging. Newer applications like construction and delivery of goods are also emerging. Performing tasks as a team of drones is often beneficial but requires coordination through communication. In this thesis, the communication requirements of video streaming drone applications based on existing works are studied. The existing communication technologies are then analyzed to understand if the communication requirements posed by these drone applications can be met by the available technologies. The shortcomings of existing technologies with respect to drone applications are identified and potential requirements for future technologies are suggested. The existing communication and routing protocols including ad-hoc on-demand distance vector (AODV), location-aided routing (LAR), and greedy perimeter stateless routing (GPSR) protocols are studied to identify their limitations in context to the drone networks. An application scenario where a team of drones covers multiple areas of interest is considered, where the drones follow known trajectories and transmit continuous streams of sensed traffic (images or video) to a ground station. A route switching (RS) algorithm is proposed that utilizes both the location and the trajectory information of the drones to schedule and update routes to overcome route discovery and route error overhead. Simulation results show that the RS scheme outperforms LAR and AODV by achieving higher network performance in terms of throughput and delay. Video streaming drone applications such as search and rescue, surveillance, and disaster management, benefit from multicast wireless video streaming to transmit identical data to multiple users. Video multicast streaming using IEEE 802.11 poses challenges of reliability, performance, and fairness under tight delay bounds. Because of the mobility of the video sources and the high data-rate of the videos, the transmission rate should be adapted based on receivers' link conditions. Rate-adaptive video multicast streaming in IEEE 802.11 requires wireless link estimation as well as frequent feedback from multiple receivers. A contribution to this thesis is an application-layer rate-adaptive video multicast streaming framework using an 802.11 ad-hoc network that is applicable when both the sender and the receiver nodes are mobile. The receiver nodes of a multicast group are assigned with roles dynamically based on their link conditions. An application layer video multicast gateway (ALVM-GW) adapts the transmission rate and the video encoding rate based on the received feedback. Role switching between multiple receiver nodes (designated nodes) cater for mobility and rate adaptation addresses the challenges of performance and fairness. The reliability challenge is addressed through re-transmission of lost packets while delays under given bounds are achieved through video encoding rate adaptation. Emulation and experimental results show that the proposed approach outperforms legacy multicast in terms of packet loss and video quality.