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Re: Proposal 0.0

From: <lists@wiltgen.net>
Date: Mon, 10 Feb 2003 21:28:01 -0800 (PST)
Message-ID: <57511.66.127.210.130.1044941281.squirrel@webmail.wiltgen.net>
To: <public-tt@w3.org>

Johnb@screen.subtitling.com wrote...

> The point I am trying to make wrt to SMIL timing models is: How do you
> synchronise the 'presentation' of the text with an external often
> discontinuous timebase.

It's pretty trivial.  Let's say you want to show the word "foo" for 5
seconds, 10 seconds from the start of a commercial.  Still assuming
Proposal 0.0, it would look something like:

<seq>
   <tt:p begin="10s" dur="5s">foo</tt:p>
</seq>

If the commercial is played at 01:03:28.720 (we don't need to know this time
a priori), then the text appears at 01:03:38.720 and ends at 01:03:43.720.

> SMIL has wallclock timebase - but that's no use.

Time is the /only/ thing that's of use, believe me.  You may believe that
God's Atomic Unit of Time is 1/29.97th of a second, but George Lucas' is
1/24th of a second, and someone encoding PAL source for the web might
consider it to be 1/12.5th of a second.

> In subtitling - the ~timed text~ is kept separate from the media it
> relates to.

Right, and Proposal 0.0 does that to your satisfaction?

-- Charles Wiltgen
   <http://playbacktime.com/>
Received on Tuesday, 11 February 2003 00:27:58 GMT

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