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Streaming technologies have made listening to music or watching movies via the internet as easy as turning on the radio or TV. address here is how the technology works.

The very first music and movie files you might find over the internet were just short clips because you had to download the entire file prior to deciding to could play it. At the present time, on the other hand, you can start playing the file as soon as the very first bytes begin to arrive... as a result of streaming.

This immediacy is possible because streaming does not send files online the same because so many other files are sent. It uses a different protocol.

A protocol is a group of rules defining how two computers connect with each other and just how they send each other data.

Most data that is sent throughout the internet is first broken up into packets (small blocks of data). The packets are sent separately and also are the rejoined at their destination so that the receiver gets the whole file.

The sending of most data online is governed by a group of rules called the Transmission Control Protocol (TCP). Streaming however uses the User Database Protocol (UDP).

Both of these protocols are quite different. The crucial difference is in how they look for errors.

If one packet gets damaged when downloading has been controlled by TCP, downloading will be suspended while that packet is resent. That way, in the event the download has been completed, you can make certain that you've got the entire data file.

When you are streaming files, alternatively, UDP allows packets to get lost now and then without interrupting the downloading. This is fine because, when an occasional packet is lost, you are unlikely to notice any interruption to the music or movie. But if everything froze very briefly while a lost packet was being resent, you probably would notice the interruption.

With streaming technology, you should not have to wait for files to be downloaded entirely prior to deciding to can begin listening to audio or watching a video. You can listen to a concert on the additional side of the world in real time, make a video call or watch a movie the same as on television.

Streaming video works in a similar way to streaming audio, except that the video has to be divided into its separate audio and video components when it is within the buffer in the RAM.

The server that holds the video for streaming shall have a video capture expansion card which will capture either a live feed from a video camera or a pre-recorded video. The capture board turns the analogue signals it receives into digital data and compresses it.

At the same time, it employs a trick to prevent having to capture more data than it needs to be able to make transmission easier.

In the event the camera used to record the video is stationary, ie, it really is not panning, the amount of data created can be reduced. This may be done because all moving images are made up of a series of frames (still images) that change in rapid succession to offer the illusion of continuous movement. The rate can be 30 frames a second which gives the video a smooth look.

The compression system reduces the range of frames needed by comparing adjacent frames and only taking account of pixels that change from one frame to another. It does this by establishing precisely what the background looks like.

As long as the camera remains still, only the changes in the frame, for example the movement of the actors, have to be transmitted. The background only has to be transmitted again in the event the camera starts to pan and the background changes.

Video streaming will likely skip frames when your Internet link is slow, which may make the video jerky. Thus the faster your connection, the smoother the video will be.

When your computer receives the video signals, it will decompress them and load them in to a small buffer in RAM as it does for audio.

At this point the signals are split into separate video and audio components which are sent to the video card and sound card respectively, whence they are output to your monitor and speakers so you can watch the film and hear the sound-track.