A Study Of Protocols Of Digital Media Exchange And Distribution

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.