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mediums, that needs to be recut and simplifi ed for best results on the Web. Adobe Premiere  and 

Adobe After Effects  software provide all the tools you need for digital video editing and visual effects.

You'll need tools for pre processing and encoding streaming media

Outputting your production as streaming media is likely to include two basic steps: pre processing 

and encoding (also referred to as compression, although compression is only part of encoding). 

Pre processing fi lters out non essential information from your video and audio information 

that is diffi cult to encode and is not required for generally accepted Web quality media. 

If you are doing a live Webcast, you'll need to set up automatic pre processing functions between 

capture and encoding. If, however, you edited your project for VOD (video on demand), you may 

have already done most, if not all, of the pre processing in the editing stage. The com 

pression part of encoding reduces the bit rate of the digital media fi le so that it can be 

WHY DO WE

effi ciently streamed at the proper bandwidth. Encoding also translates the media fi le 

NEED PLUG INS?

into the architecture's format, and may add other functionality such as digital rights 

management features.

When you click on a Web link for a media 

fi le, you depend on your browser to auto 

Gotta have a streaming media server  or two  or three 

matically  know  how to play it. 

The term  server  can either be used to refer to server software, or to computer hardware 

It  knows  because most fi les on the Web 

dedicated to serving processes. When we say that you need a specialized server to stream 

use a MIME (Multipurpose Internet Mail 

media, we are primarily referring to the server software. You'll recall from our defi nition 

Extension) format. Originally developed 

for transmitting attachments to e mail 

of streaming, that true streaming requires a specialized streaming server. Although fi les 

messages, MIME is a standard system for 

formatted for streaming can be served from a Web server, fi les cannot truly be streamed. 

identifying the type of data contained in a 

In the next section, and later in this Primer, you'll learn more about why this is so. 

fi le, based on its extension. MIME types 

that are automatically recognized and dis 

If you choose to deliver your streaming media in only one format, you need only use 

played by most browsers include format 

the server software that supports that format. But if you decide to offer more than one 

ted text fi les like HTML, graphics fi les like 

format, remember that each format must be served by its compatible server software. 

GIF and JPEG, and interactivity enhancing 

So, if you want to offer your streaming content in all three of the popular streaming 

fi les like those created in JavaScript or 

formats QuickTime, RealMedia, and Windows Media you will need to run, or have 

ActiveX.  When a browser encounters an 

 unknown  MIME type, it does one of the 

access to, servers for all three architectures.

following:

New options for serving and hosting streaming media are emerging on an almost daily 

Begins downloading the fi le and opens it 

basis. The pivotal question for every  streamer,  large or small, is whether to serve their 

with the application designated in your 

own streams or to outsource. A hosting provider may prove to be an excellent alternative 

browser preferences. 

to setting up your own server(s), if you are an individual or small business expecting 

If it does not fi nd a corresponding 

to stream just a little. If you intend to serve a lot of streaming media as part of an 

application, it may ask you with which 

application you want to open the fi le, or 

enterprise initiative, in support of e commerce, or for most any type of commercial 

it may ask if you want to download an 

endeavor you will need dedicated hardware, and/or a hosting provider. 

appropriate application.

Allows you to save the fi le to disk.

And a streaming media player  or two  or three  

Allows you to cancel the transfer.

Streaming media requires client software on the receiving end in other words, each of 

Browsers can handle practically any fi le 

the end users in your audience needs a player to see and hear your streaming media 

type, even those that they cannot display 

content. These players stream pre recorded and live media over the Internet, and can play 

themselves, by using external, or  helper,  

back media that has been saved to disk in various formats. 

applications known as plug ins. These 

auxiliary programs must be installed for 

There are two basic types of streaming media clients:  

a browser to load and display (or play) 

   Java clients Java clients quickly download a Java applet to the user's machine 

certain MIME types. Adobe Acrobat  

before the streaming content begins, so that any Java enabled browser can play back 

PDF fi les, Macromedia Flash SWF fi les, 

and video and audio fi les formatted 

the stream. Java clients can provide a virtually transparent experience for the end 

for RealMedia, Windows Media, and 

user, playing content that appears to be seamlessly embedded into a Web page, a 

namic Medianamic Media

QuickTime players are just a few of the 

yy

banner, or an e mail, without invoking a pop up window for a plug in player that 

more commonly encountered fi le types 

may interrupt the experience. Java clients do not, typically, offer the full range of 

requiring a plug in for display or playback.

end user controls provided by plug in clients. For the moment, the plug in client 

Browsers usually come with common 

model remains the popular standard.

plug ins already installed and, when they 

obe Dobe D

encounter a fi le requiring a plug in that 

   Plug in clients A plug in is an application that adds functionality to your Web 

dd

has not been installed, will often prompt 

browser. In the case of a media player, the plug in provides the client software 

AA

you to download and install it, if you 

needed to play back and control media that is either downloaded or streamed to 

choose to do so. 

the browser. The three major streaming media architectures use plug in clients.

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