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May be you have already listen radios, news, movies using streaming but may not notice what it is. I usually play BBC Nepali news via Real Player. Yes, that is one example of streaming. Server computer sends the requested item to the client in server client model. For example, when you access the yahoo page using your browser, the browser shows the content to you which are provided by yahoo server. Let me describe a little more how you are getting that data on your browser. When you request any page through browser, it connects the server that you provide. The server sends the data to you packet-by-packet. A packet is nothing but a small piece of the content that you are requesting for.

Let’s enter into Streaming. Streaming takes files-whether they are sound, video, animation or other media types- breaks them up into smaller pieces and sends them to their destination. This is very similar to how computers send information access a network or the Internet in general. [1] In the following paragraphs, I refer some web pages to solve the basic questions about streaming.

So what is a stream?

Streaming provides a mechanism that allows you to watch the movie or to listen music without downloading the whole file. Above we explain what streaming does, but not exactly what it is. At least, not what it is for RealPlayer. Each stream carries specific types of information. When you watch a video the visual part, what you watch, comes to you in one stream while the sound comes in another.

What is life streaming?

Life streaming means continuous data delivery. To guarantee a smooth playback, each data packet must be delivered with a strict deadline. [2]

How can I prepare an audio streaming?

Figure: Creating an Audio Stream [1]

As shown in figure, there are four steps to create an audio stream. Each step is described below: [1]

Step 1: Capture Audio

This step records or creates an audio which is going to change into audio stream later.

Step 2: Edit the Capture Data

Content provider adds or removes some contents on the recorded audio from step1.

Step 3: Encoding

Encoding is the process of getting file ready to be streamed. It takes a file as input and breaks it up into readable packets so that it can be sent and read. Every clip or every stream in a clip is encoded for a specific bit rate. The higher the resolution (the more information) a stream has, the higher the bandwidth it needs to get the information through to you at a useable speed.

The edited file in step2 is encoded into a stream. It means that the file is prepared to be streamed.

Step 4: Deliver the clip

The encoded file is placed on a Server to serve so that the streaming client can play it for you.

How stream players play the streamed audio?

Well, the following figure clearly shows how the process works. In this example, I just copied the figure from [2].

Step1: Open webpage say http://www.bbc.co.uk/nepali

Step 2: Click Listen Online (Chose to Daily News)

Step 3: Browser knows that the media is streamed and handovers to

RealPlayer/Windows Media Player according to your setting.

Step 4: RealPlayer plays the streamed audio.

References:

[1]. http://service.real.com/help/player/plus_manual.8/htmfiles/whatisrpp.htm#20306

[2]. http://www.cs.iastate.edu/~tobyxu/research-PLP-ROA.htm