Recursos tecnológicos audiovisuales de formación en red : sistemas streaming media y teleinmersivos.

Monográfico con el título: 'Avances tecnológicos digitales en metodologías de innovación docente en el campo de las Ciencias de la Salud en España'. Resumen basado en el de la publicación

Design of Streaming Media Panoramic Video System Based on WebGL

2016 is the outbreak year of the virtual reality industry. In the field of virtual reality, 3D surveying plays an important role. Nowadays, 3D surveying technology has received increasing attention. This project aims to establish and optimize a WebGL three-dimensional broadcast platform combined with streaming media technology. It takes streaming media server and panoramic video broadcast in browser as the application background. Simultaneously, it discusses about the architecture from streaming media server to panoramic media player and analyzing relevant theory problem. This paper focuses on the debugging of streaming media platform, the structure of WebGL player environment, different types of ball model analysis, and the 3D mapping technology. The main work contains the following points: Initially, relay on Easy Darwin open source streaming media server, built a streaming service platform. It can realize the transmission from RTSP stream to streaming media server, and forwards HLS slice video to clients; Then, wrote a WebGL panoramic video player based on Three.js lib with JQuery browser playback controls. Set up a HTML5 panoramic video player; Next, analyzed the latitude and longitude sphere model which from Three.js library according to WebGL rendering method. Pointed out the drawbacks of this model and the breakthrough point of improvement; After that, on the basis of Schneider transform principle, established the Schneider sphere projection model, and converted the output OBJ file to JS file for media player reading. Finally implemented real time panoramic video high precision playing without plugin; At last, I summarized the whole project. Put forward the direction of future optimization and extensible market.

An architecture for adaptive replication-based multimedia streaming in P2P networks

This PhD thesis addresses the issue of scalable media streaming in large-scale networking environments. Multimedia streaming is one of the largest sink of network resources and this trend is still growing as testified by the success of services like Skype, Netflix, Spotify and Popcorn Time (BitTorrent-based). In traditional client-server solutions, when the number of consumers increases, the server becomes the bottleneck. To overcome this problem, the Content-Delivery Network (CDN) model was invented. In CDN model, the server copies the media content to some CDN servers, which are located in different strategic locations on the network. However, they require heavy infrastructure investment around the world, which is too expensive. Peer-to-peer (P2P) solutions are another way to achieve the same result. These solutions are naturally scalable, since each peer can act as both a receiver and a forwarder. Most of the proposed streaming solutions in P2P networks focus on routing scenarios to achieve scalability. However, these solutions cannot work properly in video-on-demand (VoD) streaming, when resources of the media server are not sufficient. Replication is a solution that can be used in these situations. This thesis specifically provides a family of replication-based media streaming protocols, which are scalable, efficient and reliable in P2P networks. First, it provides SCALESTREAM, a replication-based streaming protocol that adaptively replicates media content in different peers to increase the number of consumers that can be served in parallel. The adaptiveness aspect of this solution relies on the fact that it takes into account different constraints like bandwidth capacity of peers to decide when to add or remove replicas. SCALESTREAM routes media blocks to consumers over a tree topology, assuming a reliable network composed of homogenous peers in terms of bandwidth. Second, this thesis proposes RESTREAM, an extended version of SCALESTREAM that addresses the issues raised by unreliable networks composed of heterogeneous peers. Third, this thesis proposes EAGLEMACAW, a multiple-tree replication streaming protocol in which two distinct trees, named EAGLETREE and MACAWTREE, are built in a decentralized manner on top of an underlying mesh network. These two trees collaborate to serve consumers in an efficient and reliable manner. The EAGLETREE is in charge of improving efficiency, while the MACAWTREE guarantees reliability. Finally, this thesis provides TURBOSTREAM, a hybrid replication-based streaming protocol in which a tree overlay is built on top of a mesh overlay network. Both these overlays cover all peers of the system and collaborate to improve efficiency and low-latency in streaming media to consumers. This protocol is implemented and tested in a real networking environment using PlanetLab Europe testbed composed of peers distributed in different places in Europe.

Brand loyalties: rethinking content within global corporate media

Translating content from one media platform to another, a process here dubbed content streaming, is the leitmotif of contemporary globalized media. Yet widely divergent interpretations of the phenomenon have emerged. Academic political economy interprets content streaming as powerfully inimical to cultural diversity, media competition and freedom of speech. Mainstream business reporting, working from an opposing media economics schema, pillories ‘synergy’-based content strategies as oversold in theory and unworkable in practice. Challenging this established trend for the disciplines to develop in parallel, the article harnesses mainstream critique of content streaming to political economy’s traditionally circumspect view of corporate media. Examining first the commercial rationales for pursuing content streaming, before turning to the financial and managerial constraints on realizing these goals, the article positions content streaming as less all-pervasive than political economists have feared, but more commercially entrenched than the financial press currently allows.

A New Approach for Video Adaptation through Overlay Services Networks

Video adaptation is an extensively explored content providing technique aimed at appropriately suiting several usage scenarios featured by different network requirements and constraints, user`s terminal and preferences. However, its usage in high-demand video distribution systems, such as CNDs, has been badly approached, ignoring several aspects of optimization of network use. To address such deficiencies, this paper presents an approach for implementing the adaptation service by exploring the concept of overlay services networks. As a result of demonstrate the benefits of this proposal, it is made a comparison of this proposed adaptation service with other strategies of video adaptation.

A series of performances in 'Translating Reviews from 1990: Art Forum'

Participation in group exhibition themed around the 25th anniversary of the Elba Benitez Gallery in Madrid. My work comprised a series of performances in which I translated reviews from the magazine Art Forum from 1990. The performances took place in various locations in London, throughout the run of the exhibition, and were streamed live to an iPad in the gallery in Madrid. I made audio visual recordings of the performances via the streaming media, which located me as the performer alongside the viewers in a single split image. These recordings were then archived in a shared folder held between the gallery and me, and which visitors to the exhibition could access when a performance was not taking place. The work extends my concerns with translation and performance, and with a consideration of how the mechanism of the gallery and the exhibition might be used to generate innovative viewing engagements facilitated by technology. The work also attempts to develop thinking and practice around the relationship between art works and their documentation - in this case the documentation and even its potential for distribution is generated as the work comes into being. The exhibition included works by Ignasi Aballí, Armando Andrade Tudela,Lothar Baumgarten, Carlos Bunga, Cabello/Carceller, Juan Cruz, Gintaras Didžiapetris, Fernanda Fragateiro, Hreinn Fridfinnsson, Carlos Garaicoa,Mario García Torres, David Goldblatt, Cristina Iglesias,Ana Mendieta, Vik Muniz, Ernesto Neto, Francisco Ruiz de Infante,Alexander Sokurov, Francesc Torres and Valentín Vallhonrat.

A Multimedia Video Player Based of FFmpeg

With the rapid development of Internet technologies, video and audio processing are among the most important parts due to the constant requirements of high quality media contents. Along with the improvement of network environment and the hardware equipment, this demand is becoming more and more imperious, people prefer high quality videos and audios as well as the net streaming media resources. FFmpeg is a set of open source program about the A/V decoding. Many commercial players use FFmpeg as their displaying cores. This paper designed a simple and easy-to-use video player based on FFmpeg. The first part is about the basic theories and related knowledge of video displaying, including some concepts like data formats, streaming media data, video coding and decoding. In a word, the realization of the video player depend on the a set of video decoding process. The general idea about the process is to get the video packets from the Internet, to read the related protocols and de-encapsulate the protocols, to de-encapsulate the packaging data and to get encoded formats data, to decode them to pixel data that can be displayed directly through graphics cards. During the coding and decoding process, there could be different degrees of data losing, which is called lossy compression, but it usually does not influence the quality of user experiences. The second part is about the principle of the FFmpeg decoding process, that is one of the key point of the paper. In this project, FFmpeg is used for the main decoding task, by call some main functions and structures from FFmpeg class libraries, packaging video formats could be transfer to pixel data, after getting the pixel data, SDL is used for the displaying process. The third part is about the SDL displaying flow. Similarly, it would invoke some important displaying functions from SDL class libraries to realize the function, though SDL is able to do not only displaying task, but also many other game playing process. After that, a independent video displayer is completed, it is provided with all the key function of a player. The fourth part make a simple users interface for the player based on the MFC program, it enable the player could be used by most people. At last, in consideration of the mobile Internet’s blossom, people nowadays can hardly ever drop their mobile phones, there is a brief introduction about how to transplant the video player to Android platform which is one of the most used mobile systems.

New Library-curated Faculty Profile Platform Launches Through bepress

As faculty needs evolve and become increasingly digital, libraries are feeling the pressure to provide relevant new services. At the same time, faculty members are struggling to create and maintain their professional reputations online. We at bepress are happy to announce the new SelectedWorks, the fully hosted, library-curated faculty profile platform that positions the library to better support faculty as well as the institution at large. Beverly Lysobey, Digital Commons and Resource Management Librarian, at Sacred Heart University, says: “Both faculty and administration have been impressed with the services we provide through SelectedWorks; we’re able to show how much our faculty really publishes, and it’s great for professors to get that recognition. We’ve had several faculty members approach us for help making sure their record was complete when they were up for tenure, and we’ve even found articles that authors themselves no longer had access to.” With consistent, organized, institution-branded profiles, SelectedWorks increases campus-wide exposure and supports the research mission of the university. As the only profile platform integrated with the fully hosted Digital Commons suite of publishing and repository services, it also ensures that the institution retains management of its content. Powerful integration with the Digital Commons platform lets the home institution more fully capture the range of scholarship produced on campus, and hosted services facilitate resource consolidation and reduces strain on IT. The new SelectedWorks features a modern, streamlined design that provides compelling display options for the full range of faculty work. It beautifully showcases streaming media, images, data, teaching materials, books – any type of content that researchers now produce as part of their scholarship. Detailed analytics tools let authors and librarians measure global readership and track impact for a variety of campus stakeholders: authors can see the universities, agencies, and businesses that are reading their work, and can easily export reports to use in tenure and promotion dossiers. Janelle Wertzbeger, Assistant Dean and Director of Scholarly Communications at Gettysburg College’s Musselman Library, says, “The new author dashboard maps and enhanced readership are SO GOOD. Every professor up for promotion & tenure should use them!” And of course, SelectedWorks is fully backed by the continual efforts of the bepress development team to provide maximum discoverability to search engines, increasing impact for faculty and institutions alike: Reverend Edward R. Udovic, Vice President for Teaching and Learning Resources at DePaul University, says, “In the last several months downloads of my scholarship from my [SelectedWorks] site have far surpassed the total distribution of all my work in the previous twenty five years.”

Media Convergence's Third Wave Content Streaming

Movies, pieces of music, books, or newspapers can all be expressed in the same binary code. Discrete forms of analogue media are just different dialects of the language of computerese. Content is becoming a very liquid asset. To take Marshall McLuhan's famed dictum a step further: The message is now independent of the medium

Media Streaming

Hundreds of streamable films and videos for free use in teaching and learning within the University of Southampton.

Think global, act global: Corporate content streaming and Australian media policy

Australia ’s media policy agenda has recently been dominated by debate over two key issues: media ownership reform, and the local content provisions of the Australia–United States Free Trade Agreement. Challenging the tendency to analyse these issues separately, the article considers them as interlinked indicators of fundamental shifts occurring in the digital media environment. Converged media corporations increasingly seek to achieve economies of scale through ‘content streaming’: multi-purposing proprietary content across numerous digitally enabled platforms. This has resulted in rivalries for control of delivery technologies (as witnessed in media ownership debates) as well as over market access for corporate content (in the case of local content debates). The article contextualises Australia’s contemporary media policy flashpoints within international developments and longer-term industry strategising. It further questions the power of media policy as it is currently conceived to deal adequately with the challenges raised by a converging digital media marketplace.

Derivation of soil-specific streaming potential electrical parameters from hydrodynamic characteristics of partially saturated soils

Water movement in unsaturated soils gives rise to measurable electrical potential differences that are related to the flow direction and volumetric fluxes, as well as to the soil properties themselves. Laboratory and field data suggest that these so-called streaming potentials may be several orders of magnitudes larger than theoretical predictions that only consider the influence of the relative permeability and electrical conductivity on the self potential (SP) data. Recent work has improved predictions somewhat by considering how the volumetric excess charge in the pore space scales with the inverse of water saturation. We present a new theoretical approach that uses the flux-averaged excess charge, not the volumetric excess charge, to predict streaming potentials. We present relationships for how this effective excess charge varies with water saturation for typical soil properties using either the water retention or the relative permeability function. We find large differences between soil types and the predictions based on the relative permeability function display the best agreement with field data. The new relationships better explain laboratory data than previous work and allow us to predict the recorded magnitudes of the streaming potentials following a rainfall event in sandy loam, whereas previous models predict values that are three orders of magnitude too small. We suggest that the strong signals in unsaturated media can be used to gain information about fluxes (including very small ones related to film flow), but also to constrain the relative permeability function, the water retention curve, and the relative electrical conductivity function.

Comment on "Streaming potential dependence on water-content in Fontainebleau sand" by V. Allegre, L. Jouniaux, F. Lehmann and P. Sailhac

Allegre et al. recently presented new experimental data regarding the dependence of the streaming potential coupling coefficient with the saturation of the water phase. Such experiments are important to model the self-potential response associated with the flow of water in the vadose zone and the electroseismic/seismoelectric conversions in unsaturated porous media. However, the approach used to interpret the data is questionable and the conclusions reached by Allegre et al. likely incorrect

Electrochemical Characterisation of Filter Media Properties and Their Exploitation in Enhanced Filtration

Streaming potential measurements for the surface charge characterisation of different filter media types and materials were used. The equipment was developed further so that measurements could be taken along the surfaces, and so that tubular membranes could also be measured. The streaming potential proved to be a very useful tool in the charge analysis of both clean and fouled filter media. Adsorption and fouling could be studied, as could flux, as functions of time. A module to determine the membrane potential was also constructed. The results collected from the experiments conducted with these devices were used in the study of the theory of streaming potential as an electrokinetic phenomenon. Several correction factors, which are derived to take into account the surface conductance and the electrokinetic flow in very narrow capillaries, were tested in practice. The surface materials were studied using FTIR and the results compared with those from the streaming potentials. FTIR analysis was also found to be a useful tool in the characterisation of filters, as well as in the fouling studies. Upon examination of the recorded spectra from different depths in a sample it was possible to determine the adsorption sites. The influence of an external electric field on the cross flow microflltration of a binary protein system was investigated using a membrane electroflltration apparatus. The results showed that a significant improvement could be achieved in membrane filtration by using the measured electrochemical properties to help adjust the process conditions.

Formal modelling for digital media distribution

Human beings have always strived to preserve their memories and spread their ideas. In the beginning this was always done through human interpretations, such as telling stories and creating sculptures. Later, technological progress made it possible to create a recording of a phenomenon; first as an analogue recording onto a physical object, and later digitally, as a sequence of bits to be interpreted by a computer. By the end of the 20th century technological advances had made it feasible to distribute media content over a computer network instead of on physical objects, thus enabling the concept of digital media distribution. Many digital media distribution systems already exist, and their continued, and in many cases increasing, usage is an indicator for the high interest in their future enhancements and enriching. By looking at these digital media distribution systems, we have identified three main areas of possible improvement: network structure and coordination, transport of content over the network, and the encoding used for the content. In this thesis, our aim is to show that improvements in performance, efficiency and availability can be done in conjunction with improvements in software quality and reliability through the use of formal methods: mathematical approaches to reasoning about software so that we can prove its correctness, together with the desirable properties. We envision a complete media distribution system based on a distributed architecture, such as peer-to-peer networking, in which different parts of the system have been formally modelled and verified. Starting with the network itself, we show how it can be formally constructed and modularised in the Event-B formalism, such that we can separate the modelling of one node from the modelling of the network itself. We also show how the piece selection algorithm in the BitTorrent peer-to-peer transfer protocol can be adapted for on-demand media streaming, and how this can be modelled in Event-B. Furthermore, we show how modelling one peer in Event-B can give results similar to simulating an entire network of peers. Going further, we introduce a formal specification language for content transfer algorithms, and show that having such a language can make these algorithms easier to understand. We also show how generating Event-B code from this language can result in less complexity compared to creating the models from written specifications. We also consider the decoding part of a media distribution system by showing how video decoding can be done in parallel. This is based on formally defined dependencies between frames and blocks in a video sequence; we have shown that also this step can be performed in a way that is mathematically proven correct. Our modelling and proving in this thesis is, in its majority, tool-based. This provides a demonstration of the advance of formal methods as well as their increased reliability, and thus, advocates for their more wide-spread usage in the future.