Encoder:
It consists of an ordinary computer, a micro-vision high-definition video acquisition card and streaming media coding software. The micro-vision streaming media acquisition card is responsible for inputting audio and video information sources into the computer for processing through coding software; The coding software is responsible for compressing the digital audio and video signals transmitted by the streaming media acquisition card into streaming media format. In the case of live broadcast, it is also responsible for uploading the compressed streaming media signal to the streaming media server in real time.
Server:
It consists of the server part of the streaming media software system and the hardware server. This part is responsible for managing, storing and distributing the streaming media programs transmitted by the encoder.
Terminal player, also known as decoder:
This part consists of the playing software of streaming media system and an ordinary PC, which is used to play the video programs that users want to watch on the streaming media server.
At present, there are three mainstream streaming media technologies, namely RealSystem of RealNetworks, WindowsMediaTechnology of Microsoft and QuickTime of Apple.
1. Apple's QuickTime.
QuickTime is a very old integration of media technology, and it is the de facto industrial standard in the field of digital media. The word "integration" is said because QuickTime is actually an open architecture, which includes all kinds of.
Various streaming media or non-streaming media technologies. QuickTime is the earliest video industry standard, and version 4.0 of QuickTime released by 1999 began to support real streaming playback. Because QuickTime itself exists.
With the convenience of the platform (MacOS), it also has many users. QuickTime uses SorensonVideo technology in video compression and QDesignMusic technology in audio part. QuickTime's biggest
Its characteristic is inclusiveness, which makes it a complete multimedia platform. Therefore, based on QuickTime, various media technologies can be used to co-produce media content. At the same time, there are three aspects in interactivity.
The best of them. For example, QuickTime files can contain files in midi, animated gif, flash and smil formats at the same time. Using the interactive format of WiredSprites in QuickTime, you can design various types of files.
Interactive interface and animation. The realization of QuickTime streaming media technology is based on the support of three softwares: QuickTime player, QuickTime editing and production and QuickTime streaming server.
RealMedia of 2.2. Real network
RealMedia has developed for a long time, so there are many advanced designs. For example, ScalableVideoTechnology can automatically adjust the media according to the speed and connection quality of the user's computer.
The playback quality of the body. Two-pass coding technology can improve the coding quality by pre-scanning the media content and then coding it according to the scanning results. Especially the SureStream adaptive streaming technology,
It is possible to provide streaming playback automatically suitable for users with different bandwidths through one coded stream. The audio part of RealMedia adopts RealAudio, which has outstanding transmission performance in low bandwidth environment. RealMedia through base
In smil, we combine our own RealPix and RealText technologies to achieve certain interactive ability and media control ability. Real streaming media technology needs the support of RealPlayer player and RealProducer.
Editing and production, RealServer server.
3. Microsoft Windows Media
WindowsMedia is the last of the three companies to enter this market, but with the convenience of its operating system, it quickly gained a larger market share. WindowsMediaVideo adopts mpeg-4 video compression technology,
The audio technology is WindowsMediaAudio. The key core of WindowsMedia is MMS protocol and ASF data format. MMS is used for network transmission control, and ASF is used for encapsulating media content and coding scheme.
At present, WindowsMedia is the weakest of the three in interactive ability, and its own ASF format interactive ability is not strong, and it has no other interactive ability except supporting smil through IE. WindowsMedia stream
The realization of media technology needs the support of WindowsMedia Player, WindowsMedia Tools and WindowsMedia Server. Generally speaking, if you use the Windows server platform,
WindowsMedia has the lowest cost. Although its function is not the best at this stage, its users are not the most.
Windows media system
Transmission protocol: mms (multimedia streaming) is completely closed.
Common streaming media file formats: asf, wmv, wma.
Organization file format: wsx
Real media system
Coding standard: mainly supports Real.
Transmission protocol: rtsp (Limited Open)
Common streaming media file formats: rm, ra
Organization file format: smi, smil
Flash media system
Transmission protocol: rtmp
Common streaming media file formats: flv, f4v.
Organization file format: swf, smil
Fast timing system (not extended)