We present parallel transport technology for 40-Gb/s Ethernet (40 GbE) over an Optical Transport Network (OTN). Key technologies that are newly implemented for 40 GbE termination and its accommodation include transcod...
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We present parallel transport technology for 40-Gb/s Ethernet (40 GbE) over an Optical Transport Network (OTN). Key technologies that are newly implemented for 40 GbE termination and its accommodation include transcoding from the 64B/66B code to 1024B/1027B code and rate adjustment using the Generic Mapping Procedure (GMP). We successfully verified the logical circuit feasibility for those functions using a Field-Programmable Gate Array (FPGA) with 136 kilo LUTs.
Today's omnipresent demand for access to multimedia content via diverse devices places new challenges on efficient content delivery. This work introduces the concept of Scalable Video Coding (SVC) tunneling develo...
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Today's omnipresent demand for access to multimedia content via diverse devices places new challenges on efficient content delivery. This work introduces the concept of Scalable Video Coding (SVC) tunneling developed in the EU FP7 ALICANTE project and shows that the quality impact of the transcoding steps for a transcoding chain from MPEG-2 to SVC and back to MPEG-2 accumulates to a PSNR reduction of up to 2.1 dB for transcoding at fixed target bitrate points. We also discuss research challenges and open issues in SVC tunneling.
Video-on-demand (VoD) is a technology that enables a subscriber to watch a selected video from a library at any time. This scheme is different from pure video broadcasting in the sense that it provides the subscriber ...
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Video-on-demand (VoD) is a technology that enables a subscriber to watch a selected video from a library at any time. This scheme is different from pure video broadcasting in the sense that it provides the subscriber the control to receive video content according to his interests. The Adapt VoD project is a multi-institutional effort to provide a flexible VoD platform for mobile devices. Adapt VoD use a context-aware approach to adapt the multimedia content and transmission parameters to the channel and device characteristics (by means of a transcoding process and adaptive modulation), saving computer and network resources and improving the system's performance.
The number of different display terminals increased steadily, from HD TV to mobile phone TV and transcoding has become an indispensable operation in video processing. In the most cases, transcoding has to be done in r...
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The number of different display terminals increased steadily, from HD TV to mobile phone TV and transcoding has become an indispensable operation in video processing. In the most cases, transcoding has to be done in real time but H.264/AVC intra-frame decoding and encoding contain a set of computation-intensive coding tools forming a loop in which the data are strongly dependant. Parallelization of each function isn't though effortless. In this paper, we present an optimized transcoding chain for AVC intra-frame stream. The transcoding chain is characterized by several operators based on loop iterations and working on 4×4 luma or 2×2 chroma blocs. This generates heavy latency. Ours approaches uses loop unrolling and data parallelization. A tradeoff is done between critical path and number of cycles in order to improve global latency. The architecture described in this paper includes a powerful CAVLC coder and decoder, an optimized transform-quantization and a frequency selection function for, respectively, requantization and quick decimation of the high frequency values in a quantified coefficient block. This whole system performs an efficient transcoding operation. Our design, thanks to a high parallelization, can decode then recode a video stream in a 1080p format at 30 frames per second (fps) in real time at the frequency of 47Mhz. This design has been implemented in a Virtex 5 FPGA. Each block is fully described giving the surface occupied and the timing diagram.
This document gives an overview about scalable media formats and describes the motivation for special administration strategies. Furthermore, a proposal for a virtual file system architecture will be presented. This a...
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This document gives an overview about scalable media formats and describes the motivation for special administration strategies. Furthermore, a proposal for a virtual file system architecture will be presented. This architecture allows for granting user rights to certain parts of a scalable file. This feature will be used for administrating scalable media files and allows the generation of different representations of the original source files without transcoding by using file-inherent scalability. The proposed architecture provides mechanisms for the generation and representation of virtual files depending on the user rights stored in an additional database.
Power consumption is a major issue for handheld devices like mobile phones that decode and display multimedia streams through networks. Their power consumption during video playback directly depends on (1) network com...
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Power consumption is a major issue for handheld devices like mobile phones that decode and display multimedia streams through networks. Their power consumption during video playback directly depends on (1) network communications required to access video streams (2) video decoding process which complexity increases according to video characteristics (codec and video dimension). This paper describes a novel system approach to reduce power consumption through video resizing. This transformation implemented on an external device (i.e. a home gateway that transport video streams from the Internet to the embedded devices) reduces the computation complexity on the handled device up to 70% and reduce its amount of network communications up to 50%.
In some online transcoding applications, such as web browsing, web contents are transcoded into the same or a different format to reduce bandwidth consumption and speed up web access for narrow bands, such as wireless...
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In some online transcoding applications, such as web browsing, web contents are transcoded into the same or a different format to reduce bandwidth consumption and speed up web access for narrow bands, such as wireless channels. In addition to the rate-distortion performance of the transcoder, transcoder complexity plays a crucial role in real time transcoding applications, since it directly affects the total access latency. This paper proposes and formulates the joint optimization problem of latency and distortion, which is related to both the rate-distortion performance and the complexity of the transcoder. A practical solution is presented to choose the right transcoder based on the available bandwidth at the time of transcoding, so as to minimize the total latency for a given distortion constraint. This is especially useful for wireless communications where the available bandwidth keeps changing due to different contributing factors.
Nowadays, the cloud computing ecosystem is more and more distributed and heterogeneous. Cloud service providers begin to build their services using cloud-based services offered by other service providers. This raises ...
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Nowadays, the cloud computing ecosystem is more and more distributed and heterogeneous. Cloud service providers begin to build their services using cloud-based services offered by other service providers. This raises several issues due to integration between services and provider themselves. In this paper, we propose a practice addressing such a concern in a "Vertical Supply Chain" scenario of distributed clouds.
In this paper, we propose an unequal error protection (UEP) technique to provide the scalable video bitstream generated by JSVM platform with error resilience ability. Currently, only the error concealment tools are s...
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In this paper, we propose an unequal error protection (UEP) technique to provide the scalable video bitstream generated by JSVM platform with error resilience ability. Currently, only the error concealment tools are supported by JSVM. However, the reconstruction quality of these tools is poor. The proposed method guarantees successful decoding of all received bits, thus leads to strong error resilience at various channel bandwidth and high robustness for streaming scalable video bitstream over a noisy link.
To support various bandwidth requirements for mobile multimedia services for future heterogeneous mobile environments, such as portable notebooks, personal digital assistants (PDAs), and 3G cellular phones, a transcod...
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To support various bandwidth requirements for mobile multimedia services for future heterogeneous mobile environments, such as portable notebooks, personal digital assistants (PDAs), and 3G cellular phones, a transcoding video proxy is usually necessary to provide mobile clients with adapted video streams by not only transcoding videos to meet different needs on demand, but also caching them for later use. Traditional proxy technology is not applicable to a video proxy because it is less cost-effective to cache the complete videos to fit all kinds of clients in the proxy. Since transcoded video objects have inheritance dependency between different bit-rate versions, we can use this property to amortize the retransmission overhead from transcoding other objects cached in the proxy. In this paper, we propose the object relation graph (ORG) to manage the static relationships between video versions and an efficient replacement algorithm to dynamically manage video segments cached in the proxy. Specifically, we formulate a transcoding time constrained profit function to evaluate the profit from caching each version of an object. The profit function considers not only the sum of the costs of caching individual versions of an object, but also the transcoding relationship among these versions. In addition, an effective data structure, cached object relation tree (CORT), is designed to facilitate the management of multiple versions of different objects cached in the transcoding proxy. Experimental results show that the proposed algorithm outperforms companion schemes in terms of the byte-hit ratios and the startup latency. (c) 2007 Elsevier B.V. All rights reserved.
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