Watching Movies Online 1

Streaming technology has made listening to music or watching free full movies online over the internet as easy as turning on the radio or TV. Here is how the technology works.

The first music and movie files you can find via the internet were just short clips because you had to download the whole file before you could play it. At the present time, conversely, you can start playing the file as soon as the first bytes begin to arrive... because of streaming.

This immediacy is possible because streaming isn't going to send files online the same since many other files are sent. It uses an alternative protocol.

A protocol is a set of rules defining how two computers connect with each other and the way 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 are the rejoined at their destination to ensure that the receiver gets the whole file.

The sending of most data via the internet 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 check for errors.

If one packet gets damaged when downloading will be 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 sure that you've got the entire data file.

Whenever you are streaming files, on the flip side, UDP allows packets to get lost now and after that 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 another 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 separated into its separate audio and video components when it really is within the buffer in the RAM.

The server that holds the video for streaming may have a video capture expansion card that can capture either a live feed from a video camera or perhaps 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 avoid 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's not panning, the amount of data created can be reduced. This can be done because all moving images are made up of a series of frames (still images) that change in rapid succession to give the illusion of continuous movement. The rate is usually 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 yet, only the changes in the frame, for example the movement of the actors, have to be transmitted. The background only must be transmitted again after the camera starts to pan as well as the background changes.

Video streaming can even 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 shall 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 can be output to your monitor and speakers so you can watch the movie and hear the sound-track.