Les réseaux centrés sur l’information (ICN) sont une architecture prometteuse pour faire face à l’explosion du trafic multimédia sur internet et à la mobilité croissante des utilisateurs: non seulement ICN peut améliorer la qualité d’expérience de l’utilisateur, mais ICN peut également étendre naturelle et de façon transparente la prise en charge du trafic vidéo dans les fonctions réseau. Cependant, à notre connaissance, une évaluation approfondie des avantages apportés par ICN à la diffusion multimédia n’a pas encore été réalisée. Dans cette thèse, nous voulons réduire l’écart qui nous sépare d’une telle évaluation en prenant en compte ICN dans divers scénarios de diffusion multimédia.Tout d’abord, nous évaluons les avantages apportés par du DAS (Dynamic Adaptive Streaming) basé sur ICN par rapport au streaming basé sur TCP/IP, au moyen d’une campagne expérimentale comprenant plusieurs canaux (des émulations Wi-Fi et LTE, des traçes 3G/4G), plusieurs clients (mélange homogène et hétérogène, arrivées synchrones et asynchrones) et des logiques d’adaptation DAS soigneusement sélectionnées pour couvrir les deux grandes familles d’algorithmes disponibles. Nous mettons aussi enexergue les pièges potentiels qui sont néanmoins facilement évitables.Ensuite, nous montrons comment l’assistance du réseau contribue à améliorer la qualité d’expérience des utilisateurs. Pour ce faire, nous tirons parti de la fonctionnalité de mise en cache réseau d’ICN et proposons un signal re ́seau simple envoyé périodiquement par le cache à exploiter par l’algorithme d’adaptation DAS pour optimiser la qualité d’expérience de l’utilisateur en évitant le phénomène bien connu des oscillations induites par le cache. Des expériences nous permettent de valider le bien-fondé de notre approche.Enfin, puisque la diffusion multimedia en direct gagne du terrain, nous proposons hICN-RTC, en intégrant hICN (hybrid ICN), une solution ICN-dans-IP, à WebRTC, accompagné du protocole RICTP (Realtime Information Centric Transport Protocol), un protocole de transport basé sur le contenu, qui minimise la latence. Bien que toujours en développement, les résultats des premières expériences sont prometteurs car ils montrent que le trafic induit par hICN-RTC ne croit qu’avec le nombre de locuteurs actifs plutôt qu’avec le nombre total de participants. / Information-Centric Networking (ICN) is a promising architecture to address today Internet multimedia traffic explosion and increasing user mobility: not only to enhance the user’s quality of experience, but also to naturally and seamlessly extend video sup- port deeper in the network functions. However, to the best of our knowledge, a thorough assessment of the benefits brought by ICN to multimedia delivery has not been done yet. In this thesis, we aim at reducing the gap to such assessment, by considering ICN in various multimedia delivery scenarios.First, we assess the benefits brought by an ICN-based Dynamic Adaptive Streaming (DAS) compared to TCP/IP based streaming, by means of an experimental campaign that includes multiple channels (e.g., emulated Wi-Fi and LTE, real 3G/4G traces), multiple clients (homogeneous vs heterogeneous mixture, synchronous vs asynchronous arrivals) and carefully selected DAS adaptation logics to cover the broad families of available adaptation algorithms. We also warn about potential pitfalls that are nonethelesseasily avoidable.Second, we show how network assistance helps im- proving the users’ quality of experience. To do so, we leverage the in-network caching feature of ICN and propose a simple periodical network signal from the cache (i.e., per-quality hit ratio) to be exploited by DAS adaptation logic to enhance further the user’s quality of experience by avoiding the known cache-induced quality oscillations. We confirm the soundness of our approach through experiments.Finally, as live multimedia delivery is gaining momentum, we propose hICN-RTC by integrating hICN (hybrid ICN), an ICN-in-IP solution, to WebRTC and we design RICTP (Realtime Information Centric Trans- port Protocol), a content-aware transport that minimizes the communication latency. Although still in development, the results we gathered from early experiments are promising as they show that hICN-RTC scales with the number of active speakers rather than the total number of participants.

The web and mobile web traffic is growing rapidly due to service accessibility in densely populated areas and massive usage of smart hand held devices (smartphones, pads and Internet dongles). This is a challenge for mobile operators and service providers, because it forces systematically increasing network throughput capacity and in parallel to keep this investment on profitable basis. On the other side, the user satisfaction with mobile broadband service should be considered as well, in order to balance the user expectations and mobile operator investments. Our work provides extensive QoE study for different conditions in sense of mobile web service, web content, network conditions and end user device. Finally, the obtained results create basis for more dimensional overview of mobile web QoE and allow to recognize quality and saturation thresholds based on network parameters. Further, obtained data provide base for design three prediction models for prediction of MOS (one for notebook, one for mobile device) and acceptability.

Ces dernières années, les terminaux mobiles sont devenus plus performants en termes de puissance de calcul, de mémoire, de taille et de la qualité de l'écran. Ces améliorations ont fortement stimulé la demande de services multimédias notamment la vidéo streaming. Par ailleurs les clients sont de plus en plus exigeants quant à la qualité rendue sur ce type de service. En plus une mauvaise expérience de la vidéo streaming a un grand impact sur la perception qu’ont les clients de l’opérateur. Optimiser la qualité d’expérience (QdE) des clients sur les services de la vidéo streaming est donc un enjeu concurrentiel majeur. Dans cette thèse, nous nous intéressons à modéliser et optimiser la QdE des services streaming en tenant compte des usages et de la mobilité des clients. En particulier, nous nous intéresserons à deux stratégies de délivrance des contenus sur le réseau mobile : la stratégie ‘’Fast Caching’’ et la stratégie ‘’On-Off’’. Nous développons des modèles analytiques qui nous permettent de calculer des indicateurs majeurs de la QdE pour le service streaming qui sont : i) la famine, qui pousse les opérateurs à envoyer plus de contenu et ii) la perte due à abandonner la lecture d’une vidéo, qui pousse ces derniers à envoyer du contenu vidéo d’une manière strictement raisonnable. Un équilibre optimal est à trouver. Nous proposons aussi des stratégies de gestion de la QdE en maintenant un bon niveau de QdE sur la totalité du réseau et en optimiser les indicateurs de la QdE du service streaming. / In recent years, mobile devices have become more powerful in terms of computing power, memory, size and screen quality. These improvements have greatly stimulated demand for multimedia services including video streaming. Moreover, customers are increasingly demanding in terms of the quality rendered on this type of service. In addition, a bad experience of video streaming has a great impact on the perception that customers have of the operator. Optimizing the quality of experience (QoE) of customers on the services of video streaming is thus a major competitive challenge. In this thesis, we are interested in modeling and optimizing the QoE of the streaming services taking into account the usages and the mobility of the clients. In particular, we are interested in two strategies for delivering content on the mobile network: the Fast Caching strategy and the On-Off strategy. We develop analytical models that allow us to calculate major indicators of the QoE for the streaming service that are: i) starvation, which drives operators to send more video content to customers and ii) the loss due to abandoning the video playback, which pushes them to send video content in a strictly reasonable manner. An optimal balance is to be found. We also propose QoE oriented strategies by maintaining a good level of QoE over the entire network and optimizing the QoE indicators of streaming services.

This thesis dissertation addresses the problem of providing video streaming services over mobile wireless ad hoc networks. This sort of network represents a hostile environment for this kind of realtime data transmission to the extent that obtaining a good quality of viewer experience is challenging and still under study. Besides the research point of view, providing high-quality multimedia services is decisive for the practical usability and feasibility of wireless ad hoc networks so that service providers can broaden the range of services offered. So far, mobile wireless ad hoc networks have been used to provide network connection among users who could not have connectivity otherwise. However, quality expectations and requirements have been increased notably, fostered by the advent of real-time multimedia applications over mobile devices. Due to the considerable processing and bandwidth constraints underlying these types of devices, coupled with their ability to move freely, it becomes a difficult task to achieve an acceptable quality of service throughout the entire video transmission. Thus, the contribution of this thesis work is twofold. On the one hand, the main problems and limitations that may be encountered and should be faced when deploying real-time services over mobile wireless ad hoc networks are analyzed and discussed. Bandwidth constraints and node mobility are portrayed as the major causes that prevent good quality of service and smooth video playback. On the other hand, following then the aim of improving video streaming quality, this thesis proposes practical solutions that involve diverse routing and cross-layer techniques. One of the proposed approaches focuses on hierarchical routing. Hierarchical arrangement of network nodes may reduce packet interference as well as offer a structured architecture that reduces control traffic overhead. Particularly, the proposed hierarchical routing protocol aims at providing scalability when the number of nodes grows, while maintaining complexity as low as possible. The resulting reduction in packet losses and video playback interruptions finally enhances the quality of received video streams. Furthermore, on the basis that the nodes in an ad hoc network are willing to perform routing tasks, every node could become essential for the proper network operation and routing performance. In tune with this philosophy, a new cross-layer mechanism for recovering lost packets is proposed. By overhearing packets over the wireless shared medium, any node in the surrounding area of the destination endpoint can altruistically retransmit those video packets that have not been correctly received at destination. Moreover, due to the video awareness and frame prioritization algorithm considered in this proposal, it becomes very convenient for real-time video streaming services. The results show that the presented mechanism succeeds in improving video quality and user experience, especially when packet losses are caused due to the mobility of the destination node. / Arce Vila, P. (2014). Hierarchical routing and cross-layer mechanisms for improving video streaming quality of service over mobile wireless ad hoc networks [Tesis doctoral]. Editorial Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/36538 / Alfresco

Communication has always been a vital part of our society, and day-to-day communication is increasingly becoming more digital. VoIP (voice over IP) is used for real-time communication, and to be able to send the information over the internet must the speech be compressed to lower the number of bits needed for transmission. Codecs are used to compress the speech, or any other type of data transmitting over a network, which can introduce some noise if lossy compression is used. Depending on the bandwidth, bit rate, and codec used can distortion be minimized which would result in higher perceived speech quality. In the thesis, two codecs, G729D and Opus, were tested and evaluated with two different objective perceive speech quality metrics, POLQA and PESQ. The codecs were also tested with different emulated network scenarios, 2G, 3G, 4G, satellite two-hop, and LAN. Furthermore, Opus was tested with and without VAD (voice activity detection) to see how VAD could affect the perceived speech quality. The different network scenarios did not impact the results of the evaluation, since the main difference between the network scenarios was latency, which POLQA and PESQ do not consider in the evaluation. Opus achieved a higher MOS-LQO (mean opinion score listening quality objective) than G729D. However, when VAD was enabled with Opus for a low bit rate, 8 kbit/s, the MOS-LQO was lower than without VAD.

Molnbaserat spelande är spelande som sker över nätverket. Spelet streamas från servrar till användarens enhet. Detta ger möjligheten att spela på enheter som inte skulle vara tillräckligt kraftfulla för att spela vissa spel på annat sätt. Mobiltelefonen är den nuvarande primära enheten för spel och fortsätter att öka i popularitet. I tidigare forskningsstudier och litteratur finns det ett uttalat behov för mätning av upplevelsekvalitet, även känt som Quality of Experience (QoE) för nylanserade molntjänster. QoE är ett sätt att undersöka användarnöjdhet och nöje för en specifik applikation eller tjänst. Denna studie redogör upplevd QoE för den molnbaserade speltjänsten Google Stadia på mobila enheter. Studien använder en kvalitativ forskningsansats med semistrukturerade intervjuer som metod för datainsamling. Resultatet analyseras med hjälp av ramverket CCA och kvalitativ innehållsanalys. Resultatet visar att upplevd QoE är bra överlag men att det finns förbättringsområden för spelupplevelsen. Denna studie utvecklar kunskapen om hur väl molnbaserade speltjänster fungerar på en mobiltelefon i dagsläget och resultatet visar behovet att liknande forskningsstudier utförs för att fördjupa denna kunskap. / Cloud gaming provides a way to play games over the network. This presents the possibility to play on devices that would not be powerful enough to play certain games otherwise. The mobile phone is the current primary device for gaming and continues to rise in popularity. In previous research studies and literature, there is an expressed necessity for measuring the Quality of Experience (QoE) of the cloud gaming services. QoE is a way to examine user satisfaction and entertainment for a specific application or service. This paper presents a study of perceived QoE for the cloud-based gaming service Google Stadia on mobile devices. The study is using a qualitative research approach with semi-structured interviews as a data collection method. The result is analyzed using the framework CCA and qualitative content analysis. The result shows that the perceived QoE is good overall but that the gaming experience has some minor inconveniences. This study expands the knowledge of how well cloud gaming services work on a mobile phone at this time and the result shows the need for similar research studies to deepen this knowledge.

Il existe deux approches classiques et bien comprises des tâches de traitement vidéo pour la vidéoconférence. Le premier utilise une unité centralisée de contrôle multipoint. Dans la deuxième approche, les tâches de traitement vidéo sont directement traitées dans les clients. La performance est ensuite limitée par les caractéristiques du périphérique. Dans cette thèse, nous proposons une troisième approche alternative. Nous proposons un système qui distribue des tâches de traitement vidéo en temps réel sur les ressources internes de l'entreprise. Une méthode dédiée de prise de décision basée sur les multi-attributs est conçue pour tenir compte de la variété des attributs qui influent sur la qualité de l'expérience. Des algorithmes de distribution et de redistribution de tâches sont élaborés. Nous testons ensuite l'approche proposée au moyen de la simulation afin d'étudier l'impact des principaux paramètres critiques. L'approche proposée pose une question sur laquelle un PC peut être utilisé comme plate-forme pour le serveur multimédia. Nous estimons une qualité perçue des flux vidéo afin d'étudier l'influence de la charge CPU. Nous avons également élaboré des algorithmes, combinant l'approche Cloud / Fog avec différents types de serveurs multimédia. Le résultat fournit une solution de conférence optimisée en termes de coût tant pour le fournisseur que pour le consommateur, ainsi que pour l'expérience de l'utilisateur final. En combinant les algorithmes élaborés et l'architecture avec les résultats de l'expérimentation, nous concluons que la solution proposée peut être utilisée comme une nouvelle approche de la problématique de la vidéoconférence. / There exist two classical and well-understood approaches to video processing tasks for videoconferencing. The first one is using a centralized Multipoint Control Unit (MCU). In the second approach, the video processing tasks are directly handled in endpoints. Performance is then restricted by device characteristics, especially in the case of mobile devices. In this thesis, we propose a third alternative approach. We propose a system, which distributes real-time video processing tasks on enterprise desktop grid. A dedicated Multi Attribute Decision Making method is designed in order to take into account the variety of attributes impacting Quality of Experience. A number of task distribution and redistribution algorithms are elaborated. We then test the proposed approach by means of simulation in order to study the impact of the main critical parameters. The proposed approach arises a question to which extent a PC can be used as a platform for media server and how CPU load affects the quality of provided video conference. We estimate a perceived quality of video streams in order to investigate CPU load influence. Also we elaborated algorithms, combining Cloud/Fog approach with different types of media servers, the result provides an optimized conferencing solution in the terms of cost for both provider and consumer as well as in terms of end user experience. Combining elaborated algorithms and architecture with experimentation results we conclude that proposed solution can be used as a novel approach to video conferencing problematic.

The research domain on the Quality of Experience (QoE) of 2D video streaming has been well established. However, a new video format is emerging and gaining popularity and availability: VR 360-degree video. The processing and transmission of 360-degree videos brings along new challenges such as large bandwidth requirements and the occurrence of different distortions. The viewing experience is also substantially different from 2D video, it offers more interactive freedom on the viewing angle but can also be more demanding and cause cybersickness. Further research on the QoE of 360-videos specifically is thus required.The first goal of this thesis is to complement earlier research by (Tran, Ngoc, Pham, Jung, and Thank, 2017) testing the effects of quality degradation, freezing, and content on the QoE of 360-videos. The second goal is to test the contribution of visual attention as influence factor in the QoE assessment. Data will be gathered through subjective tests where participants watch degraded versions of 360-videos through an HMD with integrated eye-tracking sensors. After each video they will answer questions regarding their quality perception, experience, perceptual load, and cybersickness.Results of the first part show overall rather low QoE ratings and it decreases even more as quality is degraded and freezing events are added. Cyber sickness was found not to be an issue. The effects of the manipulation on visual attention were minimal. Attention was mainly directed by content, but also by surprising elements. The addition of eye-tracking metrics did not further explain individual differences in subjective ratings. Nevertheless it was found that looking at moving objects increased the negative effect of freezing events and made participants less sensitive for quality distortions. The results of this thesis alone are not enough to successfully regard visual attention as an influence factor in 360-video.

In the current mobile telecommunication market, with slow growth in mobile subscriptions and increasing traffi demand, each mobile operator needs to manage their customer loyalty in order to maintain position in the market. To retain their customer's loyalty, the user quality of satisfaction needs to be preserved. Integrating a Quality of Experience (QoE) approach into a radio resource scheduling scheme can be a means to improve user quality of satisfaction to a service. However, the enhancement of existing resource allocation management to support a QoE-based resource scheduling scheme needs a careful consideration since it will impact the mobile operator's investment cost. A profitability assessment of QoE-based resource allocation is required as a basis for the mobile operator to forecast their potential benefit of QoE-based resource scheduling deployment. This thesis investigated the profitability of deploying QoE-based radio resource management (RRM) in terms of revenue loss compared to proportional fair (PF) scheduling, a widely used resource allocation scheme, in delivering a streaming video service. In QoE-based RRM, a buffering percentage experienced by a user was considered in the resource allocation decision process. The two scheduling schemes were simulated in different network configurations. User satisfaction was quantified in terms of mean opinion score. Given the degree of satisfaction for each user, a number of users who would be likely to churn was obtained. A cost-benefit assessment was then conducted by predicting revenue loss due to customer churn. The results from the simulation and cost analysis show that although QoE-based resource scheduling provides users with a higher degree of satisfaction for more base stations, the utilization of a QoE-based resource scheduler does not offer significant benefit to the network operator with regard to revenue loss and deployment cost when compared to a PF scheduler. This outcome indicates that if the business target is to reduce customer churn, then the operator should utilize a PF scheduler for their RRM scheme. / Den nuvarande mobiltelefonimarknaden kännetecknas av svag tillväxt av nya kunder men ett ökat nyttjande bland existerande kunder av företagens tjänster. Kundlojalitet har blivit en avgörande faktor för att uppnå en stark marknadsposition. Kundernas upplevda kvalitet utav mobiltjänsterna behöver upprätthållas på en hög nivå för att tillfredställa denna lojalitet. Att applicera en upplevad kvalitet (QoE) metod i en radio resurs kan vara ett medel till att förbättra kundernas upplevda kvalitet av mobiltj änsten. För att undersöka ifall en sådan tjänst är lönsam är det dock nödvändigt att en lönsamhetskalkyl genomförs, där investeringskostnad och systemets driftkostnad vägs mot eventuella intäkter. En lönsamhetsbedömning av QoE-baserad resursallokering krävs som grund för mobiloperatören att förutse deras potentiella fördelar med QoE-baserad resursschemaläggning. Denna uppsats undersöker lönsamheten av att implementera QoE i termer av förlorade intäkter, jämfört med proportionell rättvis (PF) schemaläggning, i att leverera en videoströmservice. I QoE-baserad RRM användes buffertprocentandel som användes av användarna i resursallokeringsprocessen.  De två olika systemen simulerades genom att använda olika antal basstationer i mobilnätverkskonfigurationen. Användarnöjdhet kvantifierades genom att låta användarna betygsätta tjänsten, detta värde användes därefter till att uppskatta hur många av kunderna som sannolikt ej skulle återanvända tjänsten. En lönsamhetskalkyl genomfördes genom att prediktera förlorade intäkter med avseende på kunderna som ej skulle återanvända tjänsten. Resultaten från simulerings- och lönsamhetsberäkningen visade att även om QoE erbjuder en högre kundnöjdhet av tjänsten och tillfredsställelse för er basstationer, så leder inte en QoE-implementering till signikanta fördelar för nätverket i termer av förlorade intäkter och investeringskostnader jämfört med ett PF schemaläggare. Detta indikerar att om ett företags mål är att höja kundlojaliteten, då skall företaget applicera en PF schemaläggare istället för QoE.

[ES] La distribución de contenidos multimedia, y en particular el streaming de vídeo, domina actualmente el tráfico global de Internet y su importancia será incluso mayor en el futuro. Miles de títulos se agregan mensualmente a los principales proveedores de servicios, como Netflix, YouTube y Amazon. Y de la mano del consumo de contenidos de alta definición que se convierte en la principal tendencia, se puede observar nuevamente un incremento en el consumo de contenidos 3D. Esto ha hecho que las temáticas relacionadas con la producción de contenidos, codificación, transmisión, Calidad de Servicio (QoS) y Calidad de Experiencia (QoE) percibidas por los usuarios de los sistemas de distribución de vídeo 3D sean un tema de investigación con numerosas contribuciones en los últimos años. Esta tesis aborda el problema de la prestación de servicios de transmisión de vídeo 3D bajo condiciones de red de ancho de banda variable. En este sentido, presenta los resultados de la evaluación de la QoE percibida por los usuarios de los sistemas de vídeo 3D, analizando principalmente el impacto de los efectos introducidos en dos de los elementos de la cadena de procesamiento de vídeo 3D: la etapa de codificación y el proceso de transmisión. Para analizar los efectos de la codificación en la calidad del vídeo 3D, en la primera etapa se aborda la evaluación objetiva y subjetiva de la calidad del vídeo, comparando el rendimiento de diferentes estándares y métodos de codificación, con el fin de identificar aquellos que logran la mejor relación entre calidad, tasa de bits y tiempo de codificación. Así mismo, en el contexto de la transmisión en un entorno simulcast, se evalúa la eficacia de la utilización de las codificaciones asimétricas para la transmisión de vídeo 3D, como una alternativa para la reducción del ancho de banda manteniendo la calidad global. En segundo lugar, para el estudio del impacto y el rendimiento del proceso de transmisión, se ha trabajado sobre la base de un sistema de transmisión dinámica adaptativa sobre HTTP (DASH) en el contexto de la transmisión de vídeo tanto 2D como 3D, utilizando diferentes escenarios de variación de ancho de banda. El objetivo ha sido el desarrollo de un marco de referencia para la evaluación de la QoE en escenarios de transmisión adaptativa de vídeo 3D, que permite analizar el impacto en la QoE del usuario frente a diferentes patrones de variación del ancho de banda, así como el rendimiento del algoritmo de adaptación frente a estos escenarios. El trabajo se enfoca en identificar el impacto en la Calidad de Experiencia del usuario que tienen aspectos como: la frecuencia, el tipo, el alcance y la ubicación temporal de los eventos de variación del ancho de banda. El sistema propuesto permite realizar mediciones de rendimiento de forma automatizada y sistemática para la evaluación de los sistemas DASH en el servicio de distribución de vídeo 2D y 3D. Se ha utilizado Puppeteer, la librería Node.js desarrollada por Google, que proporciona una API de alto nivel, para automatizar acciones en el protocolo Chrome Devtools, como iniciar la reproducción, provocar cambios de ancho de banda y guardar los resultados de los procesos de cambio de calidad, marcas de tiempo, paradas, etc. A partir de estos datos, se realiza un procesamiento que permite la reconstrucción del vídeo visualizado, así como la extracción de métricas de calidad y la evaluación de la QoE de los usuarios utilizando la recomendación ITU-T P.1203. / [CA] La distribució de continguts multimèdia, i en particular el streaming de vídeo, domina actualment el trànsit global d'Internet i la seua importància serà fins i tot mes gran en el futur. Milers de títols s'afegeixen mensualment als principals proveïdors de serveis, com ara Netflix, YouTube i Amazon. I de la mà del consum de continguts d'alta definició que es converteix en la tendència principal, es pot observar novament un increment en el consum de continguts 3D. Això ha fet que les temàtiques relacionades amb la producció de continguts, codificació, transmissió, Qualitat de Servei (QoS) i Qualitat d'Experiència (QoE) percebudes pels usuaris dels sistemes de distribució de vídeo 3D siguen un tema de recerca amb nombroses contribucions en els últims anys. Aquesta tesi aborda el problema de la prestació de serveis de transmissió de vídeo 3D sota condicions de xarxa d'ample de banda variable. En aquest sentit, presenta els resultats de l'avaluació de la QoE percebuda pels usuaris dels sistemes de vídeo 3D, analitzant principalment l'impacte dels efectes introduïts en dos dels elements de la cadena de processament de vídeo 3D: l'etapa de codificació i el procés de transmissió. Per analitzar els efectes de la codificació en la qualitat del vídeo 3D, a la primera etapa s'aborda l'avaluació objectiva i subjectiva de la qualitat del vídeo, comparant el rendiment de diferents estàndards i mètodes de codificació, per tal d'identificar aquells que aconsegueixen la millor relació entre qualitat, taxa de bits i temps de codificació. Així mateix, en el context de la transmissió en un entorn simulcast, s'avalua l'eficàcia de la utilització de les codificacions asimètriques per la transmissió de vídeo 3D, com una alternativa per la reducció de l'ampleada de banda mantenint la qualitat global. En segon lloc, per a l'estudi de l'impacte i el rendiment del procés de transmissió, s'ha treballat sobre la base d'un sistema de transmissió dinàmica adaptativa sobre HTTP (DASH) en el context de la transmissió de vídeo tant 2D com 3D, utilitzant diferents escenaris de variació d'ample de banda. L'objectiu ha estat el desenvolupament d'un marc de referència per a l'avaluació de la QoE en escenaris de transmissió adaptativa de vídeo 3D, que permet analitzar l'impacte en la QoE de l'usuari davant de diferents patrons de variació de l'ample de banda; així com el rendiment de l'algorisme d'adaptació davant d'aquests escenaris. El treball s'enfoca a identificar l'impacte a la Qualitat d'Experiència de l'usuari que tenen aspectes com ara: la freqüència, el tipus, l'abast i la ubicació temporal dels esdeveniments de variació de l'ample de banda. El sistema proposat permet realitzar mesuraments de rendiment de manera automatitzada i sistemàtica per a l'avaluació dels sistemes DASH en el servei de distribució de vídeo 2D i 3D. S'ha utilitzat Puppeteer, la llibreria Node.js desenvolupada per Google, que proporciona una API d'alt nivell, per automatitzar accions al protocol Chrome Devtools, com iniciar la reproducció, provocar canvis d'ample de banda i desar els resultats dels processos de canvi de qualitat, marques de temps, parades, etc. A partir d'aquestes dades, es fa un processament que permet la reconstrucció del vídeo visualitzat, així com l'extracció de mètriques de qualitat i l'avaluació de la QoE dels usuaris fent servir la recomanació ITU-T P.1203. / [EN] The distribution of multimedia content, and in particular video streaming, currently dominates global Internet traffic and will become even more important in the future. Thousands of titles are added monthly to major service providers such as Netflix, YouTube and Amazon. In addition to the consumption of high-definition content becoming the main trend, an increase in the consumption of 3D content can be observed again. This fact has caused that issues related to content production, encoding, transmission, Quality of Service (QoS) and Quality of Experience (QoE) perceived by users of 3D video distribution systems became a research topic with numerous contributions in recent years. This thesis addresses the problem of providing 3D video streaming services under variable bandwidth network conditions. In this sense, it presents the results of the evaluation of the QoE perceived by the users of 3D video systems, analyzing mainly the impact of the effects introduced in two of the elements of the 3D video processing chain: the encoding stage and the transmission process. To analyze the effects of the encoding process on the quality of 3D video, the first stage deals with the objective and subjective evaluation of video quality, comparing the performance of different encoding standards and methods, in order to identify those that achieve the best ratio between quality, bit rate and encoding time. Also, in the context of transmission in a simulcast environment, the advantages of using asymmetric coding for 3D video transmission is evaluated as an alternative for bandwidth reduction while maintaining overall quality. Secondly, for the study of the impact and performance of the transmission process, the work has been carried out on the basis of an adaptive dynamic over HTTP (DASH) transmission system in the context of both 2D and 3D video transmission, using different bandwidth variation scenarios. The aim has been to develop a framework for the evaluation of QoE in 3D adaptive video streaming scenarios, which allows analyzing the impact on the user's QoE against different bandwidth variation patterns, as well as the performance of the adaptation algorithm under these scenarios. The work focuses on identifying the impact on the user's Quality of Experience in aspects such as: frequency, type, range and temporal location of bandwidth variation events. The proposed system allows to perform performance measurements in an automated and systematic way for the evaluation of DASH systems in the 2D and 3D video distribution service. The tool Puppeteer, the Node.js library developed by Google, has been used, which provides a high-level API to automate actions in the Chrome Devtools protocol, such as starting playback, causing bandwidth changes and saving the results of the quality change processes, timestamps, stops, etc. From this data, a further processing is performed that allows the reconstruction of the displayed video, as well as the extraction of quality metrics and the evaluation of the QoE of the users using the ITU-T P.1203 recommendation. / Guzmán Castillo, PF. (2022). Evaluación de la QoE en un sistema de streaming adaptativo de vídeo 3D basado en DASH [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/186354 / TESIS