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RE: Why use time as a unit of measurement? (was: Proposal 0.0)

From: <Johnb@screen.subtitling.com>
Date: Wed, 19 Feb 2003 15:32:22 -0000
Message-ID: <11E58A66B922D511AFB600A0244A722E093EE7@NTMAIL>
To: glenn@xfsi.com
Cc: public-tt@w3.org, cogit@ludicrum.org

Glenn, 

>Please read SMIL 2.0 Timing and Synchronization [1], specifically
>the sections on syncBehvaior, syncTolerance, syncMaster, and hyperlink seek
behaviors.

I hope you don't think I posted before, without having first read this
section :-)

Seriously, whilst the above section quite clearly shows how delays and
pauses 
are handled, it is far from clear IMHO that it covers **discontinuities**. 
This section is predominantly written with the assumption that delivery 
interuptions have occurred and that the 'parent time container' will catch
up.

If it is valid to consider a discontinuity in the 'parent time container'
timeline 
as a seek, then I can see that this could be workable, as the hyperlink seek
behaviour 
section does make fairly strong comment on the issue of seeking forward...

"The net effect is that seeking forward to a presentation time
 puts the document into a state largely identical to that as 
 if the document presentation time advanced undisturbed to reach
 the seek time. If the presentation is authored with no beginEvent,
 endEvent or repeatEvent based timing and no automatic hyperlinks, 
 then state of the document after a seek should be identical to that
 had the document presentation time advanced undisturbed to reach the 
 seeked-to time."

regards
John Birch

The views and opinions expressed are the author's own and do not necessarily
reflect the views and opinions of Screen Subtitling Systems Limited.
Received on Wednesday, 19 February 2003 10:23:25 GMT

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