Research And Implementation Of Smart Media Transport Protocol Under Heterogeneous Networks

With the rapid development of digital broadcast network and Internet,the demand for video service consumption has been increasing while the video service is becoming the mainstream multimedia service.Meanwhile,the fusion of traditional broadcast network and Internet is becoming the goal of future network development.Thus there has been an increasing demand for the research of heterogeneous network transport protocol.This paper firstly introduced various existing multimedia transport protocol like MPEG-2 TS,RPT(Real Time protocol),MPEG-DASH(MPEG Dynamic Adaptive Streaming over HTTP)and MMT(MPEG Media Transport).The MMT protocol is highlighted and different transport protocols are compared in detail.In heterogeneous network,these has an enormous advantage in using MMT protocol over others,for MMMT support features like file storage and delivery,multiplexing and demultiplexing of media content and signaling,error-control technology.Howerver,there're still deficiencies in MMT,especially in personalized transport and laylout and error correction mechanism in application layer.In this paper,we introduced Smart Media Transport Protocol(SMT),from which some optimization and improvements based on MMT are given,including the protection mechanism of the ranging error correction which is coded data related in application layer.In order to testify the function of SMT and its related algorithm,we design the software structure of the system and realized it.Currently a sophisticated transport network could not ensure the reliable data transfer of video content,thus an end to end error control model is needed.This paper introduced an adaptive forward error correction mechanism to optimize the bandwidth distribution between source data and redundant data based on existing video content structure and features of MPEG video format.A media transport system can be sorted into sender,receiver and layout terminal.The sender functions to stream the media content which not only includes video/audio data,but also front end HTML file to customized the pages and signaling message to indicate the media content in the transport stream.Besides,content synchronization is also an obstacle in the system,and we add a NTP module in the system to solve this.To ensure the media content delivery in heterogeneous network environment,we design an API to support broadcasting physical layer.The receiver of the system functions to receive the specifying stream data based on user requirement and send it to the layout terminal.However,there may be latency and jitters in different networks,and usage of FEC would also add difficulty to the data recover.To solve this,we introduce a media source condition transfer model,and a reception caching model is designed and applied to solve the problem caused by the incomplete reception of media data.The layout terminal functions to parse and present the media content.Traditional media content contains only video and audio data which could be decoded merely by a player.But in SMT,HTML is introduced to control the presentation of media content in a more flexible way and provide a better user experience.To support this,we choose chromium browser as our presentation terminal,and redesign the presentation engine of the browser to fully support SMT.