ISO实现多媒体流的高速传输

通用串行总线（USB）是自1997年末开始为PC主板所采用的一种开放接口标准。1998年,推出了仅有两个I/O接口,即USB及以太网接口的Apple iMac。最初的USB标准（1.0及1.1）支持的最大传输率为每秒1M字节,净传输速率达12 Mbps。Windows 98是最先支持USB的操作系统,它内置了各种设备的驱动程序,其中包括鼠标、键盘及扬声器。2000年4月,USB应用者论坛（USB-IF成员包括:微软、英特尔、飞利浦、惠普、康柏、NEC及朗讯）发布了USB标准2.0。该版本增加了新的高速传输率。高速USB传输最高速率可达480 Mbps,比USB1.1的最高速度快40倍。ISO传输的特点 USB支持两种类型的数据传输:大数据块（bulk）传输     

Adaptive Streaming of Layer-Encoded Multimedia Presentations

In the context of a communication network with no QoS guarantees, we describe the problem of adaptive streaming of layer encoded multimedia presentation data as a two-phase decision problem. In phase one the application transfers only base layer data that comprise a presentation of minimum quality, which is stored at the client. When the application determines that commencing play out will result in an uninterrupted presentation of at least minimum quality, it does so, and then transitions into phase two. The application then loops on the decision on which data to send next: another base layer, or an enhancement layer. It does this by considering the deliverability and play-out quality within a sliding window of media units. We present two different algorithms for making this decision, based on two different presentation quality metrics: the total quality metric, which yields an optimization problem that can be solved with dynamic programming, and the refined max-min metric, which yields a computationally inexpensive algorithm for computing an optimal decision. We also consider the problem of progressively rendering static objects after their start times as a means of improving presentation quality. We compare the various approaches with a slide show presentation with a randomly generated sequence of layer-encoded JPEG images, and an Ogg Vorbis audio stream.     

流媒体实时传输技术的研究

阐述了流媒体实时传输技术的基本概念和协议,详细地分析了RTP协议和RTSP协议,并给出了基于该协议的流媒体传输的实例.     

Internet多媒体通信协议

下一代Ｉｎｔｅｒｎｅｔ协议将为多媒体通信提供广泛的支持,首先概述了多媒体通信的要求,分析了现有Ｉｎｔｅｒｎｅｔ协议系统在多媒体应用方面的不足,然后介绍了发展中的ＩＰ版本６、实时传输协议,资源预留协议等新型Ｉｎｔｅｒｎｅｔ多媒体通信协议。     

Vertical Handover Decision Algorithm for Multimedia Streaming in VANET

Wireless Personal Communications - Vehicular ad hoc networks represent one of the most important applications of wireless ad hoc networks. In highways, where different networks exist, frequent and...     

Region of Interest-Based Adaptive Multimedia Streaming Scheme

Adaptive multimedia streaming aims at adjusting the transmitted content based on the available bandwidth such as losses that often severely affect the end-user perceived quality are minimized and consequently the transmission quality increases. Current solutions affect equally the whole viewing area of the multimedia frames, despite research showing that there are regions on which the viewers are more interested in than on others. This paper presents a novel region of interest-based adaptive scheme (ROIAS) for multimedia streaming that when performing transmission-related quality adjustments, selectively affects the quality of those regions of the image the viewers are the least interested in. As the quality of the regions the viewers are the most interested in will not change (or will involve little change), the proposed scheme provides higher overall end-user perceived quality than any of the existing adaptive solutions.     

互联网多媒体通信

多媒体通信技术是作为通信技术和多媒体技术结合的产物，伴随着信息科技的不断发展进步，已逐渐成为当今世界科技活动中最有活力、发展最快的高新技术之一。文章描述了当前多媒体通信的典型应用，以及多媒体通信所涉及的关键核心技术，并展望了多媒体技术发展的前景和趋势。     

一种基于多路复用的多媒体流TCP友好拥塞控制机制

本文重点研究在多路复用的链路环境中,TCP友好与多媒体流最低速率阈值限定之间的权衡关系,提出了一种基于多路复用的TCP友好速率控制算法-MTCRC(Multiplexing and threshold-constrained rate control).MTCRC引入基于概率的随机试验技术,以保证多媒体流在多路复用时,当友好速率低于限定的最低速率时,通过在适当的时间对部分流的挂起操作,使多媒体流的平均吞吐量仍保持TCP友好.MTCRC是对TFRC(TCP-friendly rate control)的改进,它在保持TFRC良好的速率平滑性的同时,增加了对多媒体流最低速率阈值限定特性及多路复用链路环境的考虑,使其既能尽量保持多媒体流应用的有效性,又能与竞争的TCP流公平地分享带宽.模拟结果显示:MTCRC的性能明显优于TFRC.     

基于因特网的流式媒体技术

基于因特网的流式媒体技术是目前IP宽带业务的核心内容和关键技术，阐述了有关流媒体的基本概念、工作原理、播放方式和传输协议，并展望了该项技术的未来前景。     

宽带互联网上的流媒体业务

自2004年以来，中国的互联网用户继续保持着快速发展的势头，平均增长率为18．4％。截至2005年6月已超过1亿．其中宽带用户数达到5300万。如此巨大的用户规模为流媒体业务的快速发展提供了前所未有的机遇。特别是在3G的推动下，移动流媒体业务得到了一定规模的应用。     

基于Internet的流媒体技术

基于Interent的流媒体技术是目前IP宽带业务的核心内容和关键技术，阐述了有关流媒体技术的定义，文件格式，实现途径和过程，系统组成及相关协议，分析了流媒体技术的发展趋势。     

Peer-to-peer streaming for networked consumer electronics [Peer-to-Peer Multimedia Streaming]

Applications such as multimedia communications and entertainment make media streaming a key feature for peer-to-peer (P2P) technology embedded in networked consumer electronics. In this article, we discuss some key issues that are relevant to enabling peer-to-peer streaming in networked consumer electronics and address possible technical solutions to the issues of interoperability, NAT/firewall traversal, and codec inflexibility. We also address how to improve overall system performance by introducing a notion of node coordinates into the discovery of services on a P2P network and confirm the effectiveness of our approach using simulation. We conclude with a discussion of our prototype CE-oriented P2P streaming system.     

基于Internet互联的多媒体通信

本分析了Internet对多媒体通信的发展所起的推进作用，介绍了基于Internet的会议，会话，检索，分配，消费和收集等多媒体业务以及网络层次，业务层次，综合多媒体多端的互联技术。     

移动流媒体协议综述

综述了移动互联网中目前应用较为广泛的三种流媒体协议:HTTP渐进下载流媒体协议,基于RTSP/RTP的实时流媒体协议栈,以及苹果公司新近提出的HTTP Live Streaming协议,并对各自的优缺点和适用范围进行了分析和比较。     

A Novel Multimedia Streaming Scheme for N-Screen Services in Wireless USB Networks

Ultra wideband (UWB) technology has emerged as a solution for the wireless interface between medical sensors and a personal server in future telemedicine systems. Wireless universal serial bus (USB) is the USB technology merged with UWB technology. Wireless USB can be applied to wireless personal area network applications as well as personal area network applications like wired USB. In case of n-screen service applications, data traffics must broadcast to the adjacent devices However, the current wireless USB is designed to support the communication through the point-to-point connection between the host and the device only. This policy increases delay and energy consumption of wireless host and devices significantly. Therefore, in this paper, we propose a novel multimedia streaming scheme for n-screen service in wireless USB networks. The simulation results show that proposed protocol can enhance the throughput and delay performance and improve energy efficiency by minimizing the multimedia data delivery process.     

Multimedia broadcasting over the Internet. I

Although the industry is still in the early stages of webcasting, we can already foresee what the Internet will offer a few years down the line: clear, crisp audio and full-screen, high-quality, on-demand video. We have developed a technology that provides all these required features for Internet webcasting. This technology consists of: IP Simulcast, a new Internet broadcast protocol, which provides inexpensive, efficient, and reliable audio and video broadcasting; and new audio and video compression algorithms, which allow real-time audio and video transmission of data at low bit rates and with high quality. In this article, we describe a new Internet broadcast technology     

MPEG-4流媒体技术及其实现方法

详细地介绍了一种基于MPEG-4压缩的嵌入式网络流媒体采集、传输和控制应用系统的设计与实现技术。该嵌入式平台采用203 MHz的ARM920T内核处理器S3C2410B,嵌入式操作系统采用Linux操作系统,用户可在这个系统平台上进行自主软件开发。视频采集模块采用TI公司的TVP5145,视频压缩芯片采用硬压缩W IS GO7007B进行处理,将Y:Cb:Cr格式的视频流转换为MPEG-4编码。