A Distributed Real-Time MPEG Video Audio Player
19 Apr 1995-pp 142-153
TL;DR: This paper presents the design, implementation and experimental analysis of a distributed, real-time MPEG video and audio player designed for use across the Internet, a shared environment with variable traffic and with great diversity in network bandwidth and host processing speed.
Abstract: This paper presents the design, implementation and experimental analysis of a distributed, real-time MPEG video and audio player. The player is designed for use across the Internet, a shared environment with variable traffic and with great diversity in network bandwidth and host processing speed. We use a novel toolkit approach to build software feedback mechanisms for client/server synchronization, dynamic Quality-of-Service control, and system adaptiveness. Our experimental results show that the feedback mechanisms are effective, and that the player performs very well in the Internet environment.
Citations
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01 May 1998
TL;DR: In this paper, a review of error control and concealment in video communication is presented, which are described in three categories according to the roles that the encoder and decoder play in the underlying approaches.
Abstract: The problem of error control and concealment in video communication is becoming increasingly important because of the growing interest in video delivery over unreliable channels such as wireless networks and the Internet. This paper reviews the techniques that have been developed for error control and concealment. These techniques are described in three categories according to the roles that the encoder and decoder play in the underlying approaches. Forward error concealment includes methods that add redundancy at the source end to enhance error resilience of the coded bit streams. Error concealment by postprocessing refers to operations at the decoder to recover the damaged areas based on characteristics of image and video signals. Last, interactive error concealment covers techniques that are dependent on a dialogue between the source and destination. Both current research activities and practice in international standards are covered.
1,611 citations
TL;DR: This paper proposes a distributed QoS routing scheme that selects a network path with sufficient resources to satisfy a certain delay (or bandwidth) requirement in a dynamic multihop mobile environment and can tolerate a high degree of information imprecision.
Abstract: In an ad hoc network, all communication is done over wireless media, typically by radio through the air, without the help of wired base stations. Since direct communication is allowed only between adjacent nodes, distant nodes communicate over multiple hops. The quality-of-service (QoS) routing in an ad hoc network is difficult because the network topology may change constantly, and the available state information for routing is inherently imprecise. In this paper, we propose a distributed QoS routing scheme that selects a network path with sufficient resources to satisfy a certain delay (or bandwidth) requirement in a dynamic multihop mobile environment. The proposed algorithms work with imprecise state information. Multiple paths are searched in parallel to find the most qualified one. Fault-tolerance techniques are brought in for the maintenance of the routing paths when the nodes move, join, or leave the network. Our algorithms consider not only the QoS requirement, but also the cost optimality of the routing path to improve the overall network performance. Extensive simulations show that high call admission ratio and low-cost paths are achieved with modest routing overhead. The algorithms can tolerate a high degree of information imprecision.
878 citations
Cites methods from "A Distributed Real-Time MPEG Video ..."
...Many multimedia applications accept soft QoS and use adaptation techniques to reduce the level of QoS disruption [21]–[23]....
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TL;DR: A novel middleware control framework is presented to enhance the effectiveness of quality-of-service (QoS) adaptation decisions by dynamic control and reconfiguration of internal parameters and functionalities of a distributed multimedia application to satisfy both system-wide properties and application-specific requirements.
Abstract: In heterogeneous environments with performance variations present, multiple applications compete for and share a limited amount of system resources and suffer from variations in resource availability. These complex applications are desired to adapt themselves and to adjust their resource demands dynamically. On one hand, current adaptation mechanisms built within an application cannot preserve global properties such as fairness; on the other hand, adaptive resource management mechanisms built within the operating system are not aware of data semantics in the application. In this paper, we present a novel middleware control framework to enhance the effectiveness of quality-of-service (QoS) adaptation decisions by dynamic control and reconfiguration of internal parameters and functionalities of a distributed multimedia application. Our objective is to satisfy both system-wide properties (such as fairness among concurrent applications) and application-specific requirements (such as preserving the critical performance criteria). The framework is modeled by the task control model and the fuzzy control model, based on rigorous results from the control theory, and verified by the controllability and adaptivity of a distributed visual tracking application. The results show validation of the framework, i.e., critical application quality parameters can be preserved via controlled adaptation.
409 citations
Cites methods from "A Distributed Real-Time MPEG Video ..."
...Various software and distributed systems utilize feedback information for adaptation purpo ses [3, 21, 7]....
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...For example, the work presented in [3] uses software feedback mechanisms that enhance system a daptiveness by adjusting video sending rate according to on-the-fly network variations....
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Patent•
01 Apr 2011TL;DR: In this paper, the authors present a system that provides real-time or near-real-time streaming of content, specified in one or more playlists, using transfer protocols such as an HTTP compliant protocol.
Abstract: Methods and apparatuses provide real-time or near real-time streaming of content, specified in one or more playlists, using transfer protocols such as an HTTP compliant protocol. In one embodiment, a method can execute a user application on a client device to present media files and to control presentation of the media files. The method can further run a media serving process on the client device to retrieve a playlist specifying the media files and a media source at which the media files are available, to retrieve the media files from the media source, and to decode the media files retrieved. The media serving process can call the user application to process a custom URL in order to obtain an object referred to by the custom URL.
360 citations
Patent•
11 Dec 2003
TL;DR: In this paper, a pre-buffered ten seconds of each of the next several songs on the list is buffered so that the user can skip one or more songs without having an unintended delay between skips.
Abstract: In an Internet based personalized radio, where a user has a pre-selected list of songs to be played in a particular order, the invention provides an apparatus and method allowing the user to skip one or more songs without having an unintended delay between skips This is accomplished by pre-buffering the first ten seconds of each of the next several songs on the list so that, should the user choose to skip to any of the next several songs, the pre-buffered ten seconds of the target song is already available to be played The apparatus starts to play the pre-buffered port of the target song and starts to download the rest of it at the same time Because the initial buffering time for the rest of the target song is less than ten seconds, the target song is played smoothly
312 citations
References
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TL;DR: This paper motivates and describes the three key techniques employed by Vegas, and presents the results of a comprehensive experimental performance study—using both simulations and measurements on the Internet— of the Vegas and Reno implementations of TCP.
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1,399 citations
"A Distributed Real-Time MPEG Video ..." refers methods in this paper
...Software feedback mechanisms already exist in many forms, such as the flow control mechanism used in TCP [ 2 ], the clock synchronization mechanism used in NTP [4], and Rowe's video stream frame rate control mechanism [8]....
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01 Mar 1992
TL;DR: This document describes the Network Time Protocol (NTP), specifies its formal structure and summarizes information useful for its implementation and describes the methods used for their implementation.
Abstract: This document describes the Network Time Protocol (NTP), specifies its
formal structure and summarizes information useful for its
implementation. [STANDARDS-TRACK]
1,057 citations
01 Sep 1993
TL;DR: It is shown that memory bandwidth is the primary limitation in performance of the decoder, not the computational complexity of the inverse discrete cosine transform as is commonly thought.
Abstract: The design and implementation of a software decoder for MPEG video bitstreams is described. The software has been ported to numerous platforms including PC''s, workstations, and mainframe computers. Performance comparisons are given for several different bitstreams and platforms including a unique metric devised to compare price/performance across different platforms (percentage of required bit rate per dollar). We also show that memory bandwidth is the primary limitation in performance of the decoder, not the computational complexity of the inverse discrete cosine transform as is commonly thought.
231 citations
"A Distributed Real-Time MPEG Video ..." refers methods in this paper
...The player is written in C, using code modified from the Berkeley MPEG decoder [ 7 ], and a Motif interface based on a modified version from the University of Minnesota....
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12 Nov 1992
TL;DR: The design and implementation of a continuous media player for Unix workstations that can play synchronized digital video and audio read from a file server is described.
Abstract: The design and implementation of a continuous media player for Unix workstations is described. The player can play synchronized digital video and audio read from a file server. The system architecture and results of preliminary performance experiments are presented.
192 citations
"A Distributed Real-Time MPEG Video ..." refers background or methods in this paper
...Software feedback mechanisms already exist in many forms, such as the flow control mechanism used in TCP [2], the clock synchronization mechanism used in NTP [4], and Rowe's video stream frame rate control mechanism [ 8 ]....
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...The Berkeley Continuous Media Player [ 8 , 9] has had the most significant influence on the design and implementation of our player....
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