2,557 research outputs found
Hybrid Contribution of JPEG200 Video Files for Professional Production Centers Reliability and Non-Reliability Transmission File Based in Image Quality Needed
ATM, SDH or satellite have been used in the last century as the contribution network of Broadcasters. However the attractive price of IP networks is changing the infrastructure of these networks in the last decade. Nowadays, IP networks are widely used, but their characteristics do not offer the level of performance required to carry high quality video under certain circumstances. Data transmission is always subject to errors on line. In the case of streaming, correction is attempted at destination, while on transfer of files, retransmissions of information are conducted and a reliable copy of the file is obtained. In the latter case, reception time is penalized because of the low priority this type of traffic on the networks usually has. While in streaming, image quality is adapted to line speed, and line errors result in a decrease of quality at destination, in the file copy the difference between coding speed vs line speed and errors in transmission are reflected in an increase of transmission time. The way news or audiovisual programs are transferred from a remote office to the production centre depends on the time window and the type of line available; in many cases, it must be done in real time (streaming), with the resulting image degradation. The main purpose of this work is the workflow optimization and the image quality maximization, for that reason a transmission model for multimedia files adapted to JPEG2000, is described based on the combination of advantages of file transmission and those of streaming transmission, putting aside the disadvantages that these models have. The method is based on two patents and consists of the safe transfer of the headers and data considered to be vital for reproduction. Aside, the rest of the data is sent by streaming, being able to carry out recuperation operations and error concealment. Using this model, image quality is maximized according to the time window.
In this paper, we will first give a briefest overview of the broadcasters requirements and the solutions with IP networks. We will then focus on a different solution for video file transfer. We will take the example of a broadcast center with mobile units (unidirectional video link) and regional headends (bidirectional link), and we will also present a video file transfer file method that satisfies the broadcaster requirements
Reliable Multicast Transport for Heterogeneous Mobile IP environment using Cross-Layer Information
Reliable multicast transport architecture designed for heterogeneous mobile IP environment using cross-layer information for enhanced Quality of Service (QoS) and seamless handover is discussed. In particular, application-specific reliable multicast retransmission schemes are proposed, which are aimed to minimize the protocol overhead taking into account behaviour of mobile receivers (loss of connectivity and handover) and the specific application requirements for reliable delivery (such as carousel, one-to-many download and streaming delivery combined with recording). The proposed localized retransmission strategies are flexible configured for tree-based multicast transport. Cross layer interactions in order to enhance reliable transport and support seamless handover is discussed considering IEEE 802.21 media independent handover mechanisms. The implementation is based on Linux IPv6 environment. Simulations in ns2 focusing on the benefits of the proposed multicast retransmission schemes for particular application scenarios are presented
ULE Robust Header Compression For Ip-Based Communication Over Digital Video Broadcasting-Satellite (DVB-S) [TK5104. T261 2008 f rb].
Untuk selama 35 tahun, Internet telah berkembang dan bertumbuh dengan pesat. Disebabkan pembangunan yang mendadak, permintaan capaian Internet menjadi kian popular di mana-mana saja melalui pelbagai jenis media,
Over a span of thirty five years, the Internet has developed and grown rapidly. Due to its rapid growth, the demand for Internet access today is everywhere and over every possible medium such as satellite communications
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Integration of unidirectional technologies into wireless back-haul architecture
This thesis was submitted for the degree of Docter of Philosophy and awarded by Brunel University.Back-haul infrastructures of today's wireless operators must support the triple-play services demanded by the market or regulatory bodies. To cope with increasing capacity demand, the EU FP7 project CARMEN has developed a cost-effective heterogeneous
multi-radio wireless back-haul architecture, which may also leverage the native multicast
capabilities of broadcast technologies such as DVB-T to off-load high-bandwidth broadcast
content delivery. However, the integration of such unidirectional technologies into a packet-switched architecture requires careful considerations. The contribution of this thesis is the investigation, design and evaluation of protocols and mechanisms facilitating the integration of such unidirectional technologies into the wireless
back-haul architecture so that they can be configured and utilized by the spectrum and
capacity optimization modules. This integration mainly concerns the control plane and, in particular, the aspects related to resource and capability descriptions, neighborhood, link and Multi Protocol Label Switching (MPLS) Label-Switched Path (LSP) monitoring, unicast and multicast LSP signalling as well as topology forming and maintenance. During the course of this study we have analyzed the problem space, proposed solutions to the resulting research questions and evaluated our approach. Our results show that the now Unidirectional Technology (UDT)-aware architecture can readily consider
Unidirectional Technologies (UDTs) to distribute, for example, broadcast content
Benets of tight coupled architectures for the integration of GNSS receiver and Vanet transceiver
Vehicular adhoc networks (VANETs) are one emerging type of networks that will enable a broad range of applications such as public safety, traffic management, traveler information support and entertain ment. Whether wireless access may be asynchronous or synchronous (respectively as in the upcoming IEEE 8021.11p standard or in some alternative emerging solutions), a synchronization among nodes is required. Moreover, the information on position is needed to let vehicular services work and to correctly forward the messages. As a result, timing and positioning are a strong prerequisite of VANETs. Also the diffusion of enhanced GNSS Navigators paves the way to the integration between GNSS receivers and VANET transceiv ers. This position paper presents an analysis on potential benefits coming from a tightcoupling between the two: the dissertation is meant to show to what extent Intelligent Transportation System (ITS) services could benefit from the proposed architectur
QoS-aware flow monitoring and event creation in heterogeneous MPLS-based Wireless Mesh Networks supporting unidirectional links
Proceedings of: IEEE 9th Malaysia International Conference on Communications (MICC 2009), 15-17 December 2009, Kuala Lumpur, MalaysiaMonitoring is a crucial task in QoS-aware
networks since it provides statistics to verify that the
network performs within the committed QoS parameters.
It is especially important in a resource-constrained Carriergrade
Wireless Mesh Access Network (CG-WMAN) in order
to monitor a node’s neighborhood, established links as well
as MPLS QoS-traffic flows, so-called Label-Switched Paths
(LSPs). In this paper, we present a monitoring architecture
for LSPs in a heterogeneous CG-WMAN, where configurable
Rating Agents perform adaptive per-LSP event creation
based on monitoring statistics, QoS-requirements and overall
network state. Keeping the footprint of the monitoring
mechanism at a minimum, our approach is based on quasipassive
monitoring minimizing the transmission of extra
frames. To support unidirectional links as well as 1-to-N
multicast trees, a receiving side feedback-free mechanism
is proposed which can be extended with transmitting side
functionality. Initial results obtained in our testbed show that
we can reliably detect under-performing links according to
the QoS requirements of the payload.European Community's Seventh Framework ProgramPublicad
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