MPEG标准对多媒体产业的影响

对４个运动图像专家组标准进行了简要说明,包括它们功能和用途和总结,阐述ＭＰＥＧ－１和ＭＰＥＧ－２如何把模拟的应用方式转变数学方式,以及如何创造新的应用领域,回顾ＭＰＥＧ－４的主要应用领域,并介绍了在多媒体产业发展中具有战略性重要作用的ＭＰＥＧ－７。     

MPEG digital video-coding standards

The efficient digital representation of image and video signals has been the subject of considerable research over the past 20 years. Digital video-coding technology has developed into a mature field and products have been developed that are targeted for a wide range of emerging applications, such as video on demand, digital TV/HDTV broadcasting, and multimedia image/video database services. With the increased commercial interest in video communications, the need for international image- and video-compression standards arose. To meet this need, the Moving Picture Experts Group (MPEG) was formed to develop coding standards. MPEG-1 and MPEG-2 video-coding standards have attracted much attention worldwide, with an increasing number of very large scale integration (VLSI) and software implementations of these standards becoming commercially available. MPEG-4, the most recent MPEG standard that is still under development, is targeted for future content-based multimedia applications. We provide an overview of the MPEG video-coding algorithms and standards and their role in video communications. We review the basic concepts and techniques that are relevant in the context of the MPEG video-compression standards and outline MPEG-1 and MPEG-2 video-coding algorithms. The specific properties of the standards related to their applications are presented, and the basic elements of the forthcoming MPEG-4 standard are also described. We also discuss the performance of the standards and their success in the market place     

MPEG-1～MPEG-7的分析与评价

简要介绍MPEG-1～MPEG-7的发展过程;着重分析了MPEG-2标准及其编码策略和存在的缺陷,MPEG-4标准的新特色及其构成框架,MPEG-7标准构想所涉及的主要技术及难点等;详细介绍了MPEG系列标准的发展思路、技术原理及各自的应用领域,并展望了其对未来人类生活产生的的影响。     

MPEG: a technological basis for multimedia applications

The Moving Picture Experts Group was established in 1988 in the framework of the Joint ISO/IEC Technical Committee (JTC 1) on Information Technology. They were given the mandate to develop standards for coded representation of moving pictures, associated audio, and their combination when used for storage and retrieval on digital storage media (DSM). In April 1990 they became Working Group 11 of JTC 1/SC 2, then in November 1991, WG 11 of JTC 1/SC 29. The three original work items of the group-coding up to 1.5, 10, and 40 Mbps-were nicknamed MPEG-1, -2 and -3, respectively. The group dropped the MPEG3 work item in July 1992 when it became apparent that the functionalities supported by the MPEG-2 requirements made it redundant. The current MPEG-4 work item, first proposed in May 1991 and approved in July 1993, targets audiovisual coding at very low bit-rates     

多媒体接口标准推陈出新

根据Display Research的统计数据，2008年以前LCD（液晶显示器）的市场占有率将不断上涨，如图1所示。同时，高清数字电视和投影仪等数字视频设备的应用也越来越普遍。HDMI、DVI、VGA和LVDS等接口标准虽然已广泛的应用于PC和消费电子产品，但是现有标准在带宽、内容保护、音频支持等方面的局限性使得DisplayPort和UDI（Unified Display Interface，通用显示接口）等新标准显得更能适应市场的需求。     

信息产业部发布七项通信行业标准

前不久，信息产业部523号文件，公布了“接入网技术要求—甚高速数字用户线(VDSL)系统”、“接入网测试方法—基于以太网技术的宽带接入网设备”等七项通信行业标准。准。1．《通信局(站)低压配电系统用电涌保护器技术要求》，标准编号为YD/T1235.1-2002。该标准主要依据IEC61643-1：1998《连接至低压配电系统用电涌保护器第1部分：技术要求和测试方法》，参考IEC61312-1、UL1449、IEEEStdC62.62和YD/T5098等标准，并结合低压配电系统用电涌保护器在我国通信局(站)的实际应用情况而制定的。该标准规定了通信局(站)低压配电系统用…     

China formally issued mobile multimedia broadcasting industry standard

October 24, 2006, China SARFF （State Administration of Radio Film and Television） formally issued the China mobile multimedia broadcasting （namely, Mobile TV） industry standard. The standard is a STiMi standard self-developed in China and put into practice from November 1 this year.     

电声学、声学、音频、视频和多媒体国际标准动态

1IEC/TC29新颁布的文件IEC/TC29电声学自2004年1—4月的工作文件见表1,其中29/550/CD(2004-01-09)以前的情况已在《电声技术》2004年第2期的第70页作过报道。序号日期12004-01-0922004-01-3032004-01-3042004-03-0552004-03-05文件29/550/CD29/551/MCR29/552/CD29/553/CD29/554/INF说明IEC60118-4Ed.2:助听器第4部分,助听器用感应线圈系统磁场强度“IEC60318-5:电声人头和人耳模拟器第5部分,由耳塞同人耳耦合的助听器和耳机测量用2cc耦合腔”周期维护报告IEC60318-5的第1个CD文件:电声人头和人耳模拟器第5部分:由耳塞同人耳…     

ISO/IEC JTC 1 directions in multimedia and GII standards

This article summarizes the approach and work of ISO/IEC in the development and delivery of standards and details the main JTC 1 multimedia and global information infrastructure activities, relationships, achievements, and plans     

基于差值分析的视频隐写分析

隐写分析主要是针对图像、视频、声音等多媒体数据,在对隐写算法和隐藏信息一无所知的情况下,仅仅通过分析多媒体数据,检测其是否含有隐藏信息。提出一种对视频基帧信息进行差值分析的方法,来检测视频中是否携带隐藏信息,并利用MPEG视频文件的编解码源代码库ffmpeg,对实际视频进行了大量的分析实验,实验结果表明,对于不同的视频对象和水印嵌入率,该算法都可有效检测到隐藏信息。     

多媒体内容理解技术在电信行业中的应用

本文首先对多媒体内容理解技术进行概要介绍,然后重点结合电信行业实际情况,提出该技术在电信行业的具备较高商业价值的应用,最后介绍一种创新性的基于内容理解技术的商业搜索平台。     

2002年～2003年颁布的电声学、声学、音视频和多媒体国际标准

这里提供了2002年至2003年8月期间颁布的声学(见表1)、电声学(见表2)、音视频和多媒体(见表3)等国际标准的进展情况。“声学”是ISO/TC43的内容,国内归口SAC犤犦/TC17“全国声学标准化技术委员会”,秘书处设在中国科学院声学研究所,它涉及听觉、噪声和建声,同电声学是相邻的学科。“电声学”是IEC/TC29的范围,国内归口SAC/TC23“全国电声学标准化技术委员会”,秘书处设在中国电子科技集团公司第三研究所。“音频、视频和多媒体”的音频部分是IEC/TC100的内容,国内归口SAC/TC242“全国音频、视频和多媒体标准化委员会”,秘书处设…     

Transcoding of MPEG bitstreams

This paper discusses the problem of transcoding as it may occur in, for instance, the following situation. Suppose a satellite transmits an MPEG-compressed video signal at say 9 Mbit/s. This signal must be relayed at a cable head end. However, since the cable capacity is only limited, the cable head end will want to relay this incoming signal at a lower bit-rate of, say, 5 Mbit/s. The problem is how to convert a compressed video signal of a given bit-rate into a compressed video signal of a lower bit-rate. The specific transcoding problem discussed in this paper is referred to as bit-rate conversion. Basically, a transcoder used for such a purpose will consist of a cascaded decoder and encoder. It is shown in the paper that the complexity of this combination can be significantly reduced. The paper also investigates the loss of picture quality that may be expected when a transcoder is in the transmission chain. The loss of quality as compared to that resulting in the case of transmission without a transcoder is studied by means of computations using simplified models of the transmission chains and by means of using computer simulations of the complete transmission chain. It will be shown that the presence of two quantizers, i.e. cascaded quantization, in the transmission chain is the main cause of extra losses, and it will be shown that the losses in terms of SNR will be some 0.5 – 1.0 dB greater than in the case of a transmission chain without a transcoder.     

MPEG的声音编码

本文对ＭＰＥＧ的声音编码进行了讲解，首先对ＭＰＥＧ－１的基本算法进行介绍，然后就ＭＰＥＧ－２算法的不同进行了解说。     

MPEG标准分析

分析MPEG视频压缩标准的产生、原理及各种MPEG标准.     

Does the wireless industry really need all of these standards?

There is an ongoing proliferation of standards impacting the development of wireless technology and products. Looking at the large collection of existing and emerging standards supporting the wireless systems that are available on the market, one has to wonder whether the wireless community really need all of these standards. After examining both why and how standards are created, we can say that the more standards available, whether they are competing or complementary, the greater the choices for the market, and thus the greater the chance the market will have access to the best technologies to suit its need. The proliferation of standards in the long term fosters competition, lowers prices to consumers, and allows for innovation in other areas     

A tutorial on MPEG/audio compression

This tutorial covers the theory behind MPEG/audio compression. While lossy, the algorithm can often provide “transparent”, perceptually lossless compression, even with factors of 6-to-1 or more. It exploits the perceptual properties of the human auditory system. The article also covers the basics of psychoacoustic modeling and the methods the algorithm uses to compress audio data with the least perceptible degradation     

MPEG视频加密算法浅析

视频加密对于保护视频数据的安全具有重要作用.对已有的几种典型MPEG视频加密算法性能分别作了分析和比较,结合各类算法的特点,提出了设计加密算法的一些看法.