Abstract This paper introduces the concept of streaming media features in-depth analysis of a streaming media system and its key technology research of streaming media technology in the broadband network, application and development at home and abroad, streaming media technology in development problems are illustrated. Also view of the current status of broadband networks and put forward the application of streaming media technology and development proposals.
In broadband network construction, people gradually realize that support broadband applications are truly a source of strength development of broadband networks, but also the benefits of broadband network operators to the source. Based on the high-speed network, streaming media (StreamingMedia) technology born, its birth and development of the Internet overall framework to promote innovation, while giving more broadband applications and interactive entertainment. Currently in China's broadband network market, based on different compression methods MPEG-1, MPEG-2, REAL, WMT, QuickTime and other streaming media technology products have become the darling of broadband networks, have become an increasing concern.
1, concepts and characteristics of streaming media
Streaming media refers to the use of variable-bandwidth technology, data transmission network, and play by the time sequence of continuous audio / video data format. Streaming media players were only part of the cache, do not download the entire file, send the same spread in the data, the user can use a computer player or other appropriate hardware, software, animation compression, streaming video and audio, etc. after decompression for playback of multimedia files, thus saving download waiting time and storage space, so that delay significantly reduced, while the remaining part of the multimedia file server in the background to continue to download.
Streaming media data stream is continuous, real-time, three major characteristics of time sequence, with strict timing relationships before and after.
2, streaming media system and key technologies
1. Streaming media system components Streaming media system includes audio / video source coding / decoding, storage, streaming media servers, media streaming network, the client player, five parts, the original audio / video stream encoded and compressed to form a media file storage , the media server based on user requests to transfer media files to the client's media player.
2. Streaming Media File Format Streaming media file is a data (animation, video, etc.) sub-transmission, the user need not wait for the completion of the entire content delivery, you can watch real-time, continuous content, or even pause, fast forward, rewind. Since the development of different companies in different file formats, transmission methods also differ, the following are several popular streaming media file format.
(1) RealNetworks Inc.. Rm format and video images. Ra audio format
RealNetworks's RealSystem media content creation tools from the RealProducer, server-side RealServer, client software (ClientSoftware), whose streaming media files, including RealAudio, RealVideo, RealPresentation and RealFlash. RealAudio and RealVideo used in the adaptive flow (SureStream) technology is the RealNetworks technology company representative can be automatically and continuously adjust the flow of data streams to adapt to different practical applications of network bandwidth requirements and easily online achieve visual, audio and 3D animation playback. Real format with high compression ratio and good transmission capabilities, the streaming file with RealProducer software production, the source file, or enter into a real-time streaming file, then streaming files to the server for users on demand. Server-side software RealServer8, with network management capabilities, support for a wide range of media formats and streaming media business models. RealPlayer client a global player, enrollment has more than 160 million people, accounting for 60% of the online video streaming on-demand market.
Because of its maturity, stability, technical performance, the Internet giant America Online (AOL), ABC, AT & T, Sony and TimeLife major radio companies and online around the world use the RealSystem to deliver real-time audio and video media information and real-time music broadcasting. In China, a large number of film and television, music on demand, and the Spring Festival evening party, Kunming Expo opening ceremony webcast are using RealSystem system.
(2) Microsoft Corporation. Asf format Microsoft also launched a complete range of Streaming Media Production (MediaTools), publishing (MediaServer) and playback software (Me? Juan diaPlayer) information stream program MicrosoftMediaTechnology. MediaTools offers a range of tools to help user-generated multimedia streaming ASF format (including real-time generation of multimedia streams), is an important part of the program, which is divided into two to create tools and editing tools to create tools mainly used to generate ASF multimedia streaming formats, including MediaEncoder, Author, VidToASF, WavToASF, Presenter five tools; editing tools on the ASF format, the main flow of information in multimedia editing and management, including post-production editing tools ASFIndexer and ASFChop, and the ASF stream inspection and to correct errors ASFCheck. ASF is an included audio, video, images, and control commands, scripts, and other multimedia information including data format, through the network one by one into the Internet to transmit data packets to achieve streaming multimedia content distribution. ASF support any compression / decompression, encoding, and can use any of the underlying network transmission protocol, with a lot of flexibility. MediaServer can guarantee the confidentiality of files, not downloaded, and to each user the best video quality can browse the Web, with a variety of forms and documents issued monitoring and management capabilities. MediaPlayer provides a powerful flow of information playback, not only for Web-playing, can also be used outside the browser plays audio and video files.
Microsoft will MicrosoftMedia technology bundled in Win? Juan dows2000 in convenient, advanced, integrated, low cost and so on. In addition, ASF will also be used as a Windows version of the standard file format for multimedia content, which will undoubtedly Internet, in particular streaming technology and the development of significant impact. But the overall solutions and software, RealNetworks, a gap remains between, and only use the Microsoft platform.
(3) Apple's QuickTime
Apple Inc. began publishing in 1991, QuickTime, it supports almost all mainstream personal computing platforms and a variety of formats