【作者】 李春亮；

【导师】 蔡安妮；

【作者基本信息】 北京邮电大学 ， 多媒体通信， 2008， 硕士

【摘要】 近年来,随着信息技术、通信技术和广播电视技术飞速发展,数字媒体内容资源在各领域的应用日益广泛。在传统的广播电视之外,手机电视、网络电视等新媒体也不断涌现。这些为数字媒体内容资源在新媒体平台下的内容传输和不同平台之间内容制作的素材交换提出了的需求。早期在设备间交换数据时,一般按信号流格式在不同的设备间传输。这种情况下字幕、同步播放等元数据需要在场消隐期间传输,很容易由于设备间信号流的转换而丢失,随着数字化、网络化的发展,基于文件传输音视频数据已经成为一种必然。同时,新媒体的出现也使得数据媒体内容可以经IP网络传输到达不同的信息终端。现在,手机电视等新媒体已经逐步进入人们的日常生活中,用户可以利用手机电视随时随地的观看到各种电视节目。本文对广播电视领域文件存储与交换的主流标准--素材交换格式(MXF)进行了研究,重点分析了MXF协议的文件结构、编码格式、元数据组成及操作模式,实现了MPEG-1 layer2音频和MPEG-2数据视频在MXF文件中的同步封装,并插入了索引表、同步元数据集合和随机索引表等信息。本文还研究了其他相关文件格式通用交换格式GXF和高级制作格式AAF,并与MXF做了对比。基于MicroSoft的DirectShow技术,开发了MXF播放插件,实现了MPEG-1 layer2音频和MPEG-2视频在MXF文件中的同步播放,为今后的进一步开发作了充分的准备。DVB-H是新媒体领域中最早出现也是目前应用最广泛的手机电视标准。作为数字媒体交换和分发系统的最后一个环节,本文对DVB-H进行了研究,分析了其网络结构、协议栈和关键技术。其中对DVB-H的数据映射进行了重点分析,对DVB-H多协议封装和时间分片进行了实现。更多还原

【Abstract】 In recent years, as the rapid development of the technology of IT, communication and Digital Television, the material of digital multimedia is become more and more. Besides the traditional TV, New Medias appear without end, such as mobile TV, Net TV, etc. In this environment, the demand of exchange and distribution of digital multimedia resources among new media platforms is urgent. In early times when the material is exchanged between different equipments, the data is transmitted as signal flow and metadata such as the captions and the information of synchronized playback has to be transmitted between Vertical Blanking Intervals. This makes the metadata lost easily. Under this situation, it becomes a necessity to transmit multimedia data among equipments based on file format. At the same time, the appearance of New Medias makes TV programs can be transmitted to different user’s terminals by IP network. Now, mobile TV unified with IP network has come into people’s life as a new media and the users can watch TV in anywhere and anytime using their mobile.By studying the standard documents and related papers, the first part of this paper analyses the file structure, encode format, metadata form and operational pattern of MXF (Material eXchange Format). This part also gives a brief introduction of GXF (Generic eXchange Format) and AAF (Advance Author Format) and compares them with MXF.The second part of this paper pays more attention on the synchronous encapsulation of MPEG1 layer2 audio and MPEG-2 video in MXF file. This part also inserts necessary Index Table, metadata sets and Random Index Pack into MXF file. The file can be played by MXF player in the network.The third part of this paper introduces the Directshow technology of Microsoft and develops a new filter. With this filter, window media player can play MXF file which contains MPEG-1 layer2 audio and MPEG-2 video synchronous. As the functions of this filter are uncompleted, the other developers can further develop this filter.At last, this paper studies DVB-H as a New Media. DVB-H was emerged as the earliest mobile TV standard and also covers the most areas now. This paper makes DVB-H as the last part of the system of digital multimedia exchange and distribution and analyses the network structure, protocol stack and key technologies of DVB-H. This part also implements multiprotocol encapsulation and time slice of DVB-H.更多还原