RE: [AVT] 3GPP timed text draft: more generic?

["Jose Rey" <rey@panasonic.de>]

Hi Colin, all,


> -----Original Message-----
> From: Colin Perkins [mailto:csp@csperkins.org]
> Sent: Monday, August 11, 2003 12:03 PM
> To: Jose Rey
> Cc: avt@ietf.org
> Subject: Re: [AVT] 3GPP timed text draft: more generic?
>
>
> On Monday, Aug 11, 2003, at 09:15 Europe/London, Jose Rey wrote:
> > Colin Perkins wrote:
> >> A specific payload format for 3GPP timed text might be
> >> appropriate, but I
> >> would like to understand the options and alternatives before
> >> we make that
> >> choice. Is 3GPP the only body doing timed and/or decorated
> >> text? If not,
> >> what are the alternatives, and how do they relate?
> >>
> >> --
> >
> > at the moment there are at least two more standardisation bodies
> > interested in timed text: MPEG and W3C.
> >
> > - MPEG is currently defining their own TT format based on
> 3GPP TT (see
> > Committee Draft of ISO/IEC 14496-17 from July'03 Meeting in
> Trondheim)
> > by defining the access unit structure, the stream type, the
> object type
> > indication and decoder specific info of the timed text samples. The
> > definition of these items enables the transport over RTP using the
> > mpeg4simple draft. The work in MPEG is assumed to be
> finalised around
> > July 2004.
> >
> > - W3C is at a very early stage in defining a timed text authoring
> > format. It has recently (May'03) published a draft for use
> cases and
> > requirements of a timed text authoring format:
> > http://www.w3.org/TR/2003/WD-tt-af-1-0-req-20030515/. This
> draft has a
> > rather long list of requirements and lists many
> functionalities. In my
> > understanding W3C targets to a generic format with rich
> functionality.
> > I
> > don't know how quick it may develop (anyone?).
>
> I believe SMPTE may also have timed text work in their Digital Cinema
> group?
>

Yes, there is a DC28.2W Subtitles and Captions Adhoc Group in SMPTE
dealing with a stream timed text format. I've checked the website and as
far as I understand from the available documents they intend to develop
a media format to stream text encoded as MNG (Multi-image Network
Graphics) images. On April'02 they were still working on a requirements
document for the stream text format but no output has been published
until today, at least publicly.

Question to the group: is anyone aware of the progress of this item?

thanks,

Jose



> > None of these above is an option for us, because 1) the
> only timed text
> > format in 3GPP is 3GPP timed text 2) 3GPP has not adopted the
> > mpeg4simple for
> > transport and 3) for this 3GPP timed text format we need an
> RTP payload
> > format within the current 3GPP Release 6 schedule (i.e. March'04).
>
> I agree that using the MPEG4-simple format doesn't make
> sense, and that
> the W3C schedule looks to be too long for 3GPP requirements.
>
> --
> Colin Perkins
> http://csperkins.org/
>


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