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Re: Accessible Streaming

From: Christopher Phillips <christopher.phillips@umb.edu>
Date: Fri, 13 Feb 2004 15:48:34 -0700
Message-Id: <C0E021D5-5E76-11D8-9E4F-000393CB0664@umb.edu>
To: w3c-wai-ig@w3.org

On Feb 13, 2004, at 3:04 PM, David Woolley wrote:
> Given the choice I would almost always go for a downloadable version
> of a media file (the viewer can attempt to display it during the
> download, of course).

While there are definitely some advantages to downloadable media files, 
there are other reasons
for streaming besides protecting intellectual property. Depending on 
what type of media file and
what media player you are using to access it, sometimes you do have to 
wait for the entire file
to download before you can view it (though some players do offer 
pseudo-streaming). In addition,
  streaming at a low bitrate allows users on dial-up connections to view 
lower quality video when
downloading an entire media file would be unfeasible.

Streaming video can also be setup  so  that it delivers a stream 
appropriate to whatever the user has
set their settings as- it would deliver  different stream to someone on 
a dialup connection vs. someone
on broadband.  From a site administrator perspective, streaming also is 
a much more efficient use of
bandwith- this can be important if the video is going to be viewed by a 
lot of people.

> Although you can, normally, reposition in a streaming file, there is
> normally a long pause as the pipeline clears and the latency buffer
> is rebuilt, but with a downloaded copy, you can reposition quickly
> to any key frame.

It is important to realize that you can only reposition a downloaded 
file after it has been downloaded,
even thought the video may begin pseudo-streaming, you have to wait 
until the download is complete
to skip around.

All that said, streaming does require a streaming server to be setup 
and you don't have a copy of the file
one your local computer  once it is downloaded.

Christopher Phillips
Institute for Community Inclusion

Curb Cut Learning
http://www.communityinclusion.org/curbcut/
Received on Friday, 13 February 2004 17:48:37 UTC

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