What is streaming media technology?

From: http://www.cnblogs.com/Aweto/archive/2007/03/06/665920.html

The traditional method of transmitting audio and video information over the network is to completely download and play back the audio and video, which usually takes several minutes or even hours. Streaming Media Technology enables stream transmission. Audio, images, or animations are continuously transmitted from the server to the user's computer. You do not have to wait until the entire file is downloaded, however, you only need to watch the video after several or dozens of seconds of startup latency. When audio and video are played on the user's machine, the remaining part of the file will be downloaded from the server.

If we regard file transmission as a water-receiving process, the transmission method in the past is like setting a rule for users to use it only when a bucket of water is fully occupied, the waiting time is naturally affected by the water flow and bucket size. Streaming Transmission is to open the water head dragon, wait for a short while, the water will flow continuously, and can be used with, therefore, regardless of the size of the water flow, regardless of the bucket size, users can access the water at any time. In this sense, the word streaming media is very vivid.

Stream Transmission is divided into two types: Sequential stream transmission and real-time stream transmission.

Ordered stream transmission downloads objects in sequence. Users can watch the objects while downloading them. However, users' views are not synchronized with those transmitted on the server, after a delay, the user can see the Information uploaded by the server, or the user can see the information transmitted by the server several times ago. In this process, the user can only view the downloaded part, rather than the part that has not been downloaded. Ordered stream transmission is suitable for high-quality short video segments because it can ensure the final quality of program playback. It is suitable for audio and video programs released on websites for on-demand users.

In real-time stream transmission, audio and video information can be viewed in real time. During the viewing process, users can quickly forward or backward to view the content of the front or back, but in this transmission mode, if the network transmission is not ideal, the signal received is relatively poor.

When using streaming media technology, audio and video files must adopt the corresponding format. Files of different formats must be played using different player software ". Currently, audio and video files using streaming media technology mainly have three major "schools ".

First, Microsoft's ASF (Advanced stream format ). The suffixes of such files are. ASF and. wmv. The corresponding player is Microsoft's "media player ". You can combine graphics, sound, and animation data into an asfformat file, or convert videos and audio from other formats to asfformat, in addition, you can use sound cards and video capture cards to save data from peripherals such as microphones and video recorders to asfformat.

The second is RealNetworks's RealMedia, which includes three types of files: RealAudio, realvideo, and realflash. RealAudio is used to transmit audio data close to the CD sound quality, and realvideo is used to transmit uninterrupted video data, realflash is a high compression ratio animation format jointly launched by RealNetworks and Macromedia. The suffix of such files is. rm. The Player corresponding to the file is "RealPlayer ".

The third is Apple's QuickTime. This type of file extension is usually. mov, and its corresponding player is "QuickTime ."

In addition, MPEG, Avi, DVI, SwF, and so on are all file formats suitable for streaming media technology.

Streaming Media Technology breaks through the network bandwidth limit on multimedia information transmission to a certain extent, therefore, apsaradb for memcache is widely used in many fields such as online live broadcasting, online advertising, on-demand video, distance education, telemedicine, video conferencing, enterprise training, and e-commerce.

For news media, streaming media brings both opportunities and challenges.

Streaming Media Technology makes it possible for traditional media to open up a broader space on the Internet. The Internet access of broadcast and television media programs is more convenient, and the on-demand broadcast programs of audience and audience are simpler. the live broadcast of online audio and video will also be widely used.

Streaming Media Technology changes the traditional media's "push" type communication into the "pull" Type Communication of the audience, and the audience no longer passively accepts programs from radio and television, instead, you can receive the information you need at your convenience. This will increase the status of the audience to a certain extent, give them the initiative in news dissemination, and make their needs have a more direct impact on the activities of the news media.

The widespread use of streaming media technology will also blur the boundaries between broadcasting, television and the network. The network is both a helper and extension of broadcasting and television, and will also become a powerful competitor of broadcasting and television. Using Streaming Media Technology, the network will provide new audio and video program styles and form new business methods, such as paid on-demand services. Leveraging the advantages of traditional media and the expertise of online media, maintaining good competition and cooperation among media is the path to the development of the network and the development of traditional media in the future. The use of streaming media technology is just the beginning, and the new technology is still waiting for us. (Author: Peng LAN/researcher at the center of journalism and Social Development, Renmin University of China)