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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
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
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.
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
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.
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
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
has not been installed, will often prompt
browser. In the case of a media player, the plug in provides the client software
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.