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RE: First attempt using SMIL

for

From: John Foliot
Date: Jul 13, 2006 12:50PM

Daniel Champion wrote:
> Hi All
>
> I'm dipping my toe in the (for me) uncharted waters of accessible
> multimedia, and would appreciate some feedback and advice.

Whoa boy... Welcome to the fun stuff!

>
> We have a 10 minute promotional DVD which I've converted to
> QuickTime, and extracted the sound from in MP3 format. Captions have
> been produced, and the whole thing put together in a SMIL document.

Errr... QuickTime SMIL (as opposed to say, RealMedia SMIL, or Flash SMIL or
SAMI...)

And here-in lies the biggest problem for those of us in the trenches...
While SMIL as a specification is fairly straight-forward (Media file +
text/caption file = SMIL file), each of the media players that actually
support captioning do it differently. While Dan did not mention the steps
on how he actually arrived at his captioned QT-SMIL file, the process to
make a RealMedia-SMIL is sadly different, as is the process for the Flash
flavor (and then there is SAMI - Microsoft's own take on captioned media).

The largest issue facing the deployment of SMIL files however is not the
production aspect (which is not non-trivial) but more so the media-player
wars/plug-in requirements.

Here's the problem (and for the sake of brevity we will speak of Windows
platform only here): There is more than one media player out there, and
each of these players are competing for eyeballs. As a result, when users
are installing a third party player, they are often prompted to make the
"new" player the default player for non-native file formats; thus even if
you produce a file in the RM format, or QT, there is no guarantee that the
file will actually playback in that native player - and because Real and
QuickTime do SMIL differently... Well, they just won't work. And when you
start introducing other media players (I actually like WinAmp myself) that
attempt to be the default player... (you can see where this is going).
Remember, we have zero control over how the end user has configured their
machines/user agents.

Then there is the question of installed players: Dan, while it is a good
bet that many if not most people have the QT plug-in installed, it is not a
100% certainty, especially when you start moving into alternative user
agents. Ditto for any of the other media players. So now there is another
barrier in place that will need to be addressed to "do the right thing" -
Dan if you plan on standardizing on the QT format, ensure that a link to
download the player is readily available from the web page that contains the
SMIL file, and be specific and clear about it... Don't assume the user-agent
will assist the user in this task (this is also a cognitive issue).

>From past experience with this conundrum, I actually have reached the
conclusion that producing the Flash flavour of caption (which uses the SMIL
technology, but again it's own native output file) is actually the most
practical - unlike other media players that will play multiple media file
outputs (rm, qt, MP3, etc.) Flash is Flash is Flash. Also, the final output
is kinda slick, it allows the user to show or hide the captioning and
according to macromedia, the flash plug-in has about a 98% adoption rate
(stats and sources provided here:
http://answers.google.com/answers/threadview?id=561724)

One final note: as I recall, with the exception of Realmedia's method,
which maintains separate media and text files on the server, the other 2
outputs (QT and Flash) "mush" the text and media together for a final output
that is captioned. Because of this, I would recommend that a link to the
text only transcript used to produce the captioning also be made available
from the page that features the captioned media.

Dan, good luck on the captioning front.

JF
--
John Foliot
Academic Technology Specialist - Online Accessibility
Stanford University
560 Escondido Mall
Meyer Library 181
Stanford, CA 94305-3093

(for long time list members, yes, it's true - and I am truly excited about
my new gig. Contact me off list if you want more details)