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Re: the scope of the problem

From: Michael A. Dolan <miked@tbt.com>
Date: Wed, 12 Feb 2003 09:03:52 -0800
Message-Id: <>
To: public-tt@w3.org

Hello Jan-

Always a pleasure....

My personal view is that there are probably two distinct interchange points 
that could benefit from a standard by this group:

1. File exchange format (probably suitable for authoring and some distribution)
2. Streaming format (probably suitable for some distribution and maybe 
upstream capture)

It is not clear to me yet that these solutions can be merged into a single 
design, although there minimally has to be a mapping between them.

The latter could be pretty easily created as an abstraction of the union of 
functionality of all the existing capture and decoding systems listed in 
the pictures - starting with the comparison chart that was circulated by Glenn.

And, whether we have 1 or 2 designs, I suspect we may also need 
application-specific profiles as you suggest.  Although we need to be 
careful here as one of the requirements as I understand it is to be 
somewhat decoder-agnostic, certainly in the file exchange format.  That is, 
a single format should be targetable to DVD as well as Television and 
RTP.  So, the profiles may only apply to the streaming format?

Best regards,


At 03:38 PM 2/12/2003 +0100, jan.vandermeer@philips.com wrote:

>Hello Mike,
>Good to hear you here as well. I like your picture and your question.
> >After that, then what problem are we trying to solve, exactly?
>It is my understanding that the objective in the TTWG is to define an 
>"authoring solution" that can be used as input to the specific formats for 
>transport that you indicate in your pictures. In that sense, the TTWG 
>outcome should be orthogonal to these specific formats.
>On the other hand it could be very useful to define certain profiles for 
>the TTWG outcome, to ensure that "mapping" to certain specific formats is 
>possible. For instance it may be possible to define one "simple profile" 
>for mapping to the formats used in ATSC, DVB and DVD and a second 
>"enhanced profile" for mapping to the 3GPP timed text format (which has 
>richer functionality than the first three mentioned formats).
>Best regards,
>Jan van der Meer
>Sent by:
>2003-02-11 06:05 PM
>         To:        public-tt@w3.org (W3C Public TT)
>         cc:        (bcc: Jan vanderMeer/EHV/CE/PHILIPS)
>         Subject:        the scope of the problem
>         Classification:        Unclassified
>Attached please find a rough stab at the scope of the "timed text problem",
>at least as I understand it (which is surely incomplete).
>The first slide shows some author/capture on the left and some general
>decoder applications areas on the right.  Subsequent slides show the
>existing decoders in each of the application areas (the ones I know about,
>I've added interface specifications in italics where I knew what they were,
>and "?" everywhere I either did not know, or is not defined.  Most of the
>"?" are opportunities for standardization by this group.
>I think it would be helpful if we can fill this out completely.
>After that, then what problem are we trying to solve, exactly?  It is
>highly unlikely that the decoder inputs deployed today will be
>replaced.  That is certainly true of television, and perhaps the others.
>Michael A. Dolan  TerraByte Technology    (619)445-9070
>PO Box 1673 Alpine, CA 91903 USA  FAX: (208)545-6564
>[attachment "TDE.pdf" deleted by Jan vanderMeer/EHV/CE/PHILIPS]

Michael A. Dolan  TerraByte Technology    (619)445-9070
PO Box 1673 Alpine, CA 91903 USA  FAX: (208)545-6564
Received on Wednesday, 12 February 2003 12:04:15 UTC

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