手机电视技术及应用探析

手机电视的业务本质是一种移动数据业务，是利用手机终端为用户提供视频资讯服务。作为多技术、多媒体融合的产物，手机电视正在成为一种独特的新媒体形态，而被广泛关注。本文介绍了手机电视实现方式，分析比较了DVB-H、MediaFLO、TIS-DMB等手机电视主要技术标准和信道、信源编码等技术要求，并结合国内政策条件，国内外手机电视应用情况等分析了手机电视的业务模式和应用环境。     

数字电视视频编码技术的研究

数字电视作为当前电视发展的方向在学术界和工业界引起了广泛的关注,而作为数字电视信息载体中的关键技术,视频编码技术也成为发展的核心。介绍了期望于应用在数字电视领域的视频编码技术的演进,以及H.264这一当前最新标准的技术原理和特点。     

手机电视的发展现状和趋势

随着移动数据业务的普及、手机性能的提高以及数字电视技术和网络技术的迅速发展,从2003年开始,世界各国的主要电信运营商纷纷推出手机电视业务。所谓”手机电视”,就是利用具有操作系统和视频功能的智能手机观看电视。由于手机用户普及率高且手机具有携带方便等特性,因此手机电视比普通电视具有更广泛的影响力。     

融合网络宽带IP互动电视技术方案设计

随着科学技术的不断进步,互动电视广泛应用于人们的日常生活当中。大体上说来,互动电视技术包含了计算机技术、视频编码解码技术等多个领域,是一门综合性的科学。伴随着电视技术的不断发展,互动电视技术也必然会得到相应的提高,在生活中发挥更加重要的作用。本文将介绍融合网络宽带IP的互动电视技术设计,为今后互动电视技术的深入发展提供一定的理论依据。     

3D电视系统的构成及发展

主要介绍了3D电视系统的现状与发展,按照由双视点向未来多视点3D电视系统发展的技术路线,依次介绍了各阶段系统的架构.同时,对关键技术的基本原理也做了详细说明,包括过度阶段的帧兼容、多视点视频编码、混合分辨率视频编码、视频与相应深度信息联合编码等解决方案.最后对3D电视系统中有待解决的问题和未来的研究方向进行了总结.     

网络视频编码技术

随着视频信息在网络上的应用需求的日益广泛和迫切,适合网络传输的视频编码技术成为了现在研究的一个热点,文章旨在综述网络视频编码技术的发展历程。详细介绍并对比了目前主要的网络视频编码技术:传统的视频编码技术在传输中的应用,视频的可扩展性编码以及视频的多描述编码,最后进一步阐述了未来网络视频编码技术可能的发展方向,分析了综合运用各种编码技术的可能。     

T-DMB技术及其应用

多媒体技术和移动通信技术的飞速发展激发了人们进行视频信息交流的需求。本文针对手机电视三大标准之一的T-DMB标准,介绍了T-DMB系统的历史和基本原理,进而阐述了T-DMB系统MUSICAM 信号源编码、COFDM信道编码调制、单频同步网等关键技术及其在上海的应用。     

超高清电视系统关键技术

本文研究了超高清电视国内外发展现状,对超高清电视系统的图像参数进行了分析介绍;在我们追求信息量大和视觉享受更美好的同时带来的问题是数据量的急剧增加,对视频的压缩编码和传输都提出了很高的要求,本文介绍了高效视频编码(HEVC)技术框架,分析了HEVC的关键技术.     

CMMB移动电视解决方案U-TVPlayer

随着移动广播技术的发展和带有视频功能手机的日益普及,移动电视业务获得了快速发展,并形成相当大的市场规模.分析了移动电视的产业链,并介绍了一套基于CMMB标准体系的移动电视解决方案.     

沉浸式视频编码技术综述

随着虚拟现实、增强现实等沉浸式媒体技术的发展,沉浸式视频的表示、存储、传输和显示等各个环节都受到了科研及产业界的广泛关注。沉浸式视频更复杂的视频特性和庞大的数据量,对传统视频编码技术提出了挑战,新的编码技术应运而生。该文从视频自由度(DoF)出发,分别从3DoF和6DoF两个方面介绍沉浸式视频编码技术的最新成果。3DoF视频相关编码技术包括投影模型、运动估计模型和3DoF视频编码标准。6DoF视频相关编码技术包括视频表示形式、虚拟视点合成技术、6DoF视频编码技术及运动图像专家组沉浸式视频(MPEG, MIV)编码标准。最后,对沉浸式视频及其编码技术的发展进行总结和展望。     

H.264视频压缩关键技术及其应用前景

ISO/IEC和ITU-T联合制定的H.264标准,标志着视频压缩技术的最新进展.H.264视频编码新标准采用一系列最新的压缩技术,提高了压缩率.该文重点介绍了视频编码新标准H.264的关键模块,并阐述了它在数字电视、高清晰度电视以及移动通信等方面的应用前景.     

Video coding in bisdn with a distribution rate of approximately 135 mb/s

Video coding for Broadband Integrated Services Digital Network (BISDN) is analysed, and coding techniques that use sub-Nyquist sampling are proposed. Specifically, recommendations are given for digital video coding for EQTV distribution in the area of BISDN at a payload rate of approximately 135 Mb/s. The contribution signal that is used in video production will either be the CCIR Recommendation 601 signal or a minor modification of it to maximize horizontal resolution. Also, the scanning parameters will be the same as NTSC so that the same monitor can be used to display either EQTV or NTSC TV. A compatible vertical improvement can be added initially, or in the future, that will provide additional vertical resolution beyond the capability of the present NTSC TV, or the capabilities of Recommendation 601. Finally, several coding techniques for video distribution are configured to maximize horizontal resolution given the above constraints. Two of these video coding techniques allow extra bandwidth by using sub-Nyquist sampling techniques together with comb filtering. This EQTV system will produce a horizontal resolution that is close to values normally used for HDTV.     

Configurable Media Codec Framework： A Stepping Stone for Fast and Stable Codec Development

Recent advances in reconfigurable computing have led to new ways of implementing complex algorithms while maintaining reasonable throughput.Video codecs are becoming more complex in order to provide efficient compression for video with ever-increasing resolution.This problem is compounded by the fact that spectra of video decoding devices has become wider in the move from traditional TV to cable and satellite TV,IPTV,mobile TV,and Internet media.MPEG is tackling this problem with a reconfigurable video coding(RVC) framework and is standardizing a modular definition of tools and connections.MPEG’s work started with video coding and has recently extended to graphics data coding.RVC will be supported by non-MPEG standards such as the Chinese audio-video standard(AVS).This article gives a brief background to the reconfigurable codec framework.The key to this framework is reconfigurability and reducing granularity to find commonality between different standards.     

DVC转码技术研究

本文介绍了DVC(分布式视频编码)到传统视频转码的方案,该转码方案适用于移动终端设备之间的视频通信。着重讲述了DVC到H.264的转码,针对转码过程中复杂度高和时延长等问题,利用DVC解码端生成的运动矢量来减少H.264编码的工作量,在几乎不影响视频质量的前提下,极大地降低了转码的计算复杂度和时间,提高了转码效率。同时介绍了DVC转到其它传统视频的方法和方案,最后分析了DVC转码在当前移动视频通信市场中存在的巨大潜能,以及对转码技术的未来发展和方向进行了展望。     

Advertising Insertion in Sports Webcasts

Sports content continues to generate a global appeal that transcends national, cultural, religious, and gender boundaries. Historically, TV technology's success has been intertwined with the development of televised sports. In the famous words of pioneering TV sports director Harry Coyle, "television got off the ground because of sports." Sports showcases offer a splendid platform to promote new media technologies. During the 2006 FIFA (Federation Internationale de Football Association) World Cup tournament in Germany, major mobile companies launched a plethora of mobile TV services with such offerings as video streaming, text-based services, ring-tone downloads, and mobile blogging proposes a new way of enhancing the commercial value of sports video Webcasts. Clearly, the amount of advertising exposures must be managed to avoid viewers' perceiving them as unnecessary clutter in the video. As with legacy video broadcasting systems staffed by human operators, this check can be easily managed manually. Automatic machine detection techniques, however, can further facilitate advertising content insertion     

Feedback-based error control for mobile video transmission

We review feedback-based low bit-rate video coding techniques for robust transmission in mobile multimedia networks. For error control on the source coding level, each decoder has to make provisions for error detection, resynchronization, and error concealment, and we review techniques suitable for that purpose. Further, techniques are discussed for intelligent processing of acknowledgment information by the coding control to adapt the source coder to the channel. We review and compare error tracking, error confinement, and reference picture selection techniques for channel-adaptive source coding. For comparison of these techniques, a system for transmitting low bit-rate video over a wireless channel is presented and the performance is evaluated for a range of transmission conditions. We also show how feedback-based source coding can be employed in conjunction with precompressed video stored on a media server. The techniques discussed are applicable to a wide variety of interframe video schemes, including various video coding standards. Several of the techniques have been incorporated into the H.263 video compression standard, and this standard is used as an example throughout     

基于BT.656的电视视频硬件解码的分析与实现

根据ITU-R BT.656电视视频编码原理,通过硬件解码的方式将每一帧视频图像的有效数据提取出来后传送给播放器显示.同时在保持视频不失真的前提下将视频有效数据按照一定的比例规格进行过滤,最终实现按比例缩小视频的目的.这种通过硬件解码的处理图像方式既能按比例缩小视频尺寸又能节省CPU的占用率,能很好的适应电视系统在手机等小屏幕视窗的数码产品的需求,具有广大的市场应用前景.     

中国移动多媒体广播技术分析

随着广播电视的数字化及与移动技术的相互融合,中国的手机电视业务发展迅速,以手机电视为代表的移动多媒体广播（CMMB）在奥运会期间发挥了重大作用,成为现在的热点话题。对CMMB手机电视业务的网络框架、标准、各种技术：信道传输技术、信源编码和解码、时间分片技术等方面进行了阐述,最后给出了CMMB的发展前景和优势,在不久的将来,CMMB移动多媒体技术必将成为中国主流的技术。     

Joint video coding of MPEG-2 video programs for digitalbroadcasting services

In digital broadcasting services such as digital satellite TV, cable TV, and digital terrestrial TV, several video programs are compressed by MPEG-2 and then simultaneously transmitted over a conventional CBR (constant bit rate) broadcasting channel. In this environment, the picture quality of the aggregated video programs should be kept as equal as possible to provide fair video services for all the viewers. We propose a joint video coding scheme for ensuring that the picture quality of all the programs are nearly the same. This objective is achieved by simultaneously controlling the video encoders to generate the VBR (variable bit rate) compressed video streams. This paper contributes in two ways. First, we propose a rate-distortion estimation method for MPEG-2 video, which enables us to predict the amount of bits and the distortion generated from an encoded picture at a given quantization step size and vice versa. The most attractive features of the proposed estimation method are its accuracy and a computational complexity low enough to be applied to real-time video coding applications. Second, this paper presents an efficient and accurate joint video coding scheme using the rate-distortion estimation results. The experimental results show that our coding scheme gives a higher and more stable picture quality and a more efficient channel utilization than an independent coding scheme that encodes each program independently     

面向3G环境下的移动视频编码技术

 随着移动通信迈入3G时代,在众多的3G增值业务中,移动视频业务无疑将会成为3G业务的核心应用,以视频编码技术为代表的多媒体技术是支撑移动业务运营的基础技术。本文首先介绍了面向3G环境下的移动视频业务的发展现状及其面临的技术问题;然后从可分级编码、视频转码、多描述编码、基于视觉特性的编码几个方面论述了针对移动视频的编码技术;最后对面向3G环境下的移动视频编码技术进行了总结和展望。