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RE: TT and subtitling

From: <Johnb@screen.subtitling.com>
Date: Wed, 5 Feb 2003 10:22:07 -0000
Message-ID: <11E58A66B922D511AFB600A0244A722E093EAB@NTMAIL>
To: geoff_freed@wgbh.org
Cc: public-tt@w3.org

I wrote:
>However these distinctions are IMHO far removed from the requirements of a
>TT standard - which should be to define an agnostic mechanism for the timed
>delivery of text. Using XML, tags to provide distinction between the text
>categories (for want of a better term) should be optional, but undefined by
>the standard. The TT standard should IMHO only **define** tags that are
>necessary for the temporal control of the display of text.

Geoff Freed wrote:
>I'm not so sure we can get away with this.  There are examples today of
multi-level
>line-21 captioning (e.g., verbatim vs edited to a specific reading level),
with no way
>to easily indicate what's in the data streams.  We could perhaps solve that
with
>metadata that defines at least two types of data...

>verbatim:true/false
>level: x, xx, xxx, etc., where x=editing level, reading speed, whatever

>...indicating to the user that two or three or four streams of data exist.
Of course, this
>opens up the problem of defining levels.  I'm not sure that's appropriate
for this
>group.  But we could at least leave space for the options.  

But these issues are surely outside of the scope of the TT charter? How
could any standard predict all the potential markup tags required to define
the semantics of text? I have no problem with providing a mechanism to
associate **private** semantic tags with text data, but as to indicating
what is in the streams - this is surely the role of an index or table of
contents? In DVB subtitling, where multiple subtitle streams exist, the
viewer is presented with a list of available streams from which they may
select the subtitles of their choice. This list is created by the 'decoder'
from information carried within the stream. The exact implementation of the
list and the selection mechanism is up to the 'decoder'. Some decoders do
not provide subtitles at all!

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, 5 February 2003 05:13:43 GMT

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