RE: Media Types in 3GPP Timed text draft (was: RE: [AVT] RTP andMedia Types)

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

Dave, Colin,

--cut--
> >
> >If this analysis is OK, we could register both and clearly state the
> >scenarios in which each of them is used.  This would enable a client that
> >just understands UTF8/16 and the payload format to receive the
> text/3gpp-tt
> >w/o implementing the more complex timed text decoder, which may
> be useful.
> >A side effect of using this classification is that the registration *does
> >implicitly* follow the traditional rules.
> >
> >Looking forward to your comments,
> >
>
> Since this payload format always has some binary fields, the text
> cannot be correctly extracted without understanding it, whether or
> not modifiers are present.

As Colin said, for limited domains of applicability you can also register
under text/, without complying with the traditional rules:

"The slides you quote are my interpretation of the traditional rules for
media under the "text" top level type. As you know, there has been some
discussion on relaxing these rules for media types with limited domain
of applicability. The RTP Payload Format for 3GPP timed text might fall
into this new category. Accordingly, we have this MIME review to decide
if the format should be "text" or "video"."


>  I therefore feel that it should be either
> (a) only under text/ or (b) only under video/.  I don't see any
> advantage to splitting it like this;  the 3gpp-payload-unaware
> terminal can't make any more sense of a packet without modifiers than
> it can one with them.

Therefore I don't think this is the criteria to judge text/ it appropriate
or not, but rather whether there are differentiated domains of applicability
for which the timed text format can be used. In my previous email I tried to
classify intuitively in those that need just text and the ones that need
text AND video.

The answer to this different question might as well be no ;), but I had the
feeling we talked past each other.

Cheers,

Jose

PS: Colin, would RTP payload headers be part of the "software that
understands it"?)



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