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Streaming Media Examples

1. What is streaming?
2. Examples of Streaming Media
3. Steps to create Streaming Content
4. Embedding Streaming into a Web page
5. SMIL

1. What is Streaming ?

Streaming is a technology for delivering audio and video content across a network without waiting for the entire file to download. When a request for content is made, the content is partially downloaded and stored in a buffer, after which the content begins to play.

Unlike a downloaded file, data is not saved to the hard disk when the content is done streaming. Using a streaming media system enables you to deliver content in real time without having to wait for files to download. Content that is streamed is not saved and thus cannot be replayed.

Learn More: Introduction to Streaming media production from RealNetworks http://smilparse.real.com/showcase/marketing/video_series/smil/intro.smil

There are two kinds of streaming:

Progressive streaming (on demand) and
Real-time streaming (live or in real-time)

Progressive streaming takes a compressed video file and downloads it to your hard drive via HTTP over the Internet. Depending on the format of the video, some progressive files may require you to download the entire video before playing it. QuickTime supports a 'fast start' feature which automatically kick-starts your video player as it downloads.

For Real-time streaming, video streamed for real-time plays automatically. You don't need to download the entire video before playing. You can jump to any location in the video clip. And the clip always resides on the server. You'll find real-time streaming is best suited for longer videos -- such as live event broadcasts, presentations, training videos and lectures -- where users can skip ahead to other parts of the clip and don't have to download a huge video file.

2. Examples of Streaming Media

Examples of Streaming video at different bit rates :

Real Streaming Technology	Mircosoft Streaming Technology
Real Player 56k	Windows Media Player 56k
Real Player 225k	Windows Media Player 128k
Real Player 450k	Windows Media Player 256k
Real Player (MPEG1)	Windows Media Player (MPEG4)

Examples of Rich-media Presentations:

SMIL	Microsoft Producer
WebCT Courses Demonstration 2002	WebCT Courses Demonstration 2002

3. Steps to create Streaming Content

Step 1 : Creating streaming content
1. Record your presentation
It can be existing analog (tape) content, or a live event that you can record using a microphone or camera.

2. Convert it into a digital file format that is stored on a computer
You can digitalize the files by using audio/video capture card then encoded, or converted files into streaming media file format. All you need is simple encoding software.

Some Encoding softwares :

Step 2 : Broadcasting streaming content
A streaming media server is required to broadcast your video content.
You can set up your own streaming media server or use existing video hosting services.

Three popular streaming servers:
QuickTime Streaming Server , Real Networks Server , Windows Media Server .

Step 3 : Viewing streaming content
When a user discovers an audio or video clip they want to experience, they simply click on the link or file within the Web page. Then their media player software automatically retrieves that file from the streaming media server. The media player launches and begins to play the content in real-time-there's no waiting for the file to download Player

4. Embedding Streaming into a Web page

You can build different Streaming Video into a Web page by embedding it. The first advantage of embedding is that you have complete control over the look of the player and how it functions,in other words, the entire user experience. You can create a player that works with the design of a page, and you can expose only those functions that are appropriate. You can, for example, expose only two buttons "play" and "stop" and set the player to play only one file.

Here are the HTML embeding syntax of the most common Streaming video Format :

Embedding Windows Media Player

Embedding Real Player

Embedding QuickTime

Notices :

Text in RED : Uneditable;
Text in Green : Editable;
Text in Blue : Path to your streaming video;
Text in Orange : Optional

You can simply copy and paste the corresponding code and make changes to fit your style.

Additional Reference
W3C standard of <Object> and <Embed>
http://www.w3.org/TR/WD-object-960422.html

QuickTime reference
http://developer.apple.com/quicktime

Real reference
http://www.audiovideoweb.com/emded_real_html.htm

Windows Media reference
http://www.microsoft.com/windows/windowsmedia/default.mspx

5. SMIL

SMIL stands for Synchronized Multimedia Integration Language.
Pronounce it "smile" !
It was developed by the World Wide Web Consortium
and released on June 15th 1998

SMIL is XML-based and is very similar with HTML
SMIL tags have to be ended and written in lower case as it is case-sensitive

I t is used to combine text, audio and video in a page position media elements wherever you want on the screen synchronize those elements display media following user-preferences, language, bit-rate, etc...