1,453 research outputs found

    vSkyConf: Cloud-assisted Multi-party Mobile Video Conferencing

    Get PDF
    As an important application in the busy world today, mobile video conferencing facilitates virtual face-to-face communication with friends, families and colleagues, via their mobile devices on the move. However, how to provision high-quality, multi-party video conferencing experiences over mobile devices is still an open challenge. The fundamental reason behind is the lack of computation and communication capacities on the mobile devices, to scale to large conferencing sessions. In this paper, we present vSkyConf, a cloud-assisted mobile video conferencing system to fundamentally improve the quality and scale of multi-party mobile video conferencing. By novelly employing a surrogate virtual machine in the cloud for each mobile user, we allow fully scalable communication among the conference participants via their surrogates, rather than directly. The surrogates exchange conferencing streams among each other, transcode the streams to the most appropriate bit rates, and buffer the streams for the most efficient delivery to the mobile recipients. A fully decentralized, optimal algorithm is designed to decide the best paths of streams and the most suitable surrogates for video transcoding along the paths, such that the limited bandwidth is fully utilized to deliver streams of the highest possible quality to the mobile recipients. We also carefully tailor a buffering mechanism on each surrogate to cooperate with optimal stream distribution. We have implemented vSkyConf based on Amazon EC2 and verified the excellent performance of our design, as compared to the widely adopted unicast solutions.Comment: 10 page

    Multimedia content modeling and personalization

    Get PDF

    Effect of oil palm empty fruit bunches (OPEFB) fibers to the compressive strength and water absorption of concrete

    Get PDF
    Growing popularity based on environmentally-friendly, low cost and lightweight building materials in the construction industry has led to a need to examine how these characteristics can be achieved and at the same time giving the benefit to the environment and maintain the material requirements based on the standards required. Recycling of waste generated from industrial and agricultural activities as measures of building materials is not only a viable solution to the problem of pollution but also to produce an economic design of building

    The crowd as a cameraman : on-stage display of crowdsourced mobile video at large-scale events

    Get PDF
    Recording videos with smartphones at large-scale events such as concerts and festivals is very common nowadays. These videos register the atmosphere of the event as it is experienced by the crowd and offer a perspective that is hard to capture by the professional cameras installed throughout the venue. In this article, we present a framework to collect videos from smartphones in the public and blend these into a mosaic that can be readily mixed with professional camera footage and shown on displays during the event. The video upload is prioritized by matching requests of the event director with video metadata, while taking into account the available wireless network capacity. The proposed framework's main novelty is its scalability, supporting the real-time transmission, processing and display of videos recorded by hundreds of simultaneous users in ultra-dense Wi-Fi environments, as well as its proven integration in commercial production environments. The framework has been extensively validated in a controlled lab setting with up to 1 000 clients as well as in a field trial where 1 183 videos were collected from 135 participants recruited from an audience of 8 050 people. 90 % of those videos were uploaded within 6.8 minutes

    Analysis and Summary of Feasible Marketplace Business Models Covering All Trials

    No full text
    This report analyses the market for cloud services of the type that POSTMARK is pioneering including type, scale, readiness and barriers to adoption. The POSTMARK trials are reviewed in terms of the business benefits that the services offer, the validation of these by those involved in the trials, and the further work needed to move from trials to a fully commercial and production setting. Business benefits were wide ranging and included lowering costs, better meeting of deadlines, increase in volume of business, and improved customer service. Response from the trials was positive in all cases. This was echoed by the two public demonstration events hosted by the project in 2012 where the attendees (around 100 in total from the film and post communities) were positive about the services that POSTMARK is offering. The main barriers encountered were security, the need for high levels of availability and trust, the need for complete out-of-the box solutions, and of course concerns over cost. These mirror findings in industry surveys and analyst reports. These barriers are not insurmountable but do require further investment to address. The key question is whether the market as a whole is sufficiently aware of, and ready to adopt, new services of the type developed by POSTMARK.Indications are good, but large scale adoption would be necessary to give sufficient return on the investmentneeded to provide fully operational POSTMARK services on a supported and commercial basis

    An autonomic delivery framework for HTTP adaptive streaming in multicast-enabled multimedia access networks

    Get PDF
    The consumption of multimedia services over HTTP-based delivery mechanisms has recently gained popularity due to their increased flexibility and reliability. Traditional broadcast TV channels are now offered over the Internet, in order to support Live TV for a broad range of consumer devices. Moreover, service providers can greatly benefit from offering external live content (e. g., YouTube, Hulu) in a managed way. Recently, HTTP Adaptive Streaming (HAS) techniques have been proposed in which video clients dynamically adapt their requested video quality level based on the current network and device state. Unlike linear TV, traditional HTTP- and HAS-based video streaming services depend on unicast sessions, leading to a network traffic load proportional to the number of multimedia consumers. In this paper we propose a novel HAS-based video delivery architecture, which features intelligent multicasting and caching in order to decrease the required bandwidth considerably in a Live TV scenario. Furthermore we discuss the autonomic selection of multicasted content to support Video on Demand (VoD) sessions. Experiments were conducted on a large scale and realistic emulation environment and compared with a traditional HAS-based media delivery setup using only unicast connections
    • …
    corecore