Re: Draft TTML Codecs Registry

i can see this subject is not going to be resolved easily as we clearly
have a large gap about requirements; e.g., i think there are no
requirements to signal content conformance, but only client processor
requirements, i think we must use the TTML profile mechanism, etc

On Thursday, May 15, 2014, Michael Dolan <mdolan@newtbt.com> wrote:

> Maybe "highly undesirable", but if we don't address the A + B signaling
> explicitly, then profiles need to be created for all the combinitorics of
> namespaces in practice. Not the end of the world, but virtually prevents
> the
> simple signaling of 3rd party namespaces already provided by the
> namespace/schemaLocation mechanism today. No I am not proposing we use that
> - I am pointing out a deficiency in this proposal that we already address
> today in 14496.
>
> Anyway, we need to go through the points in my email a week ago - if not
> today, then on the 29th.
>
>         Mike
>
> -----Original Message-----
> From: David Singer [mailto:singer@mac.com <javascript:;>]
> Sent: Thursday, May 15, 2014 5:20 AM
> To: Glenn Adams
> Cc: TTWG
> Subject: Re: Draft TTML Codecs Registry
>
> OK
>
> Though it will be a sub-parameter of the codecs parameter for the MP4 file
> type, from the point of view of TTML it's actually a profile short name
> registry rather than codecs registry, so I think we should rename it.
>
> the values here should be usable in both
> a) the profiles parameter for the TTML mime type
> b) the codecs parameter for the MP4 mime type
>
> so, also "named codecs" -> "named profiles"
>
>
>
> I agree with Cyril that we only need a single operator here (implement one
> of these profiles and you're good to go), both because we don't need the
> complexity, and because a "implement both/all of these" is effectively
> inviting file authors to make up new profiles ("to process this document
> you
> have to implement both A and B"), which is (IMHO) highly undesirable.
>
>
>
> On May 15, 2014, at 9:55 , Glenn Adams <glenn@skynav.com <javascript:;>>
> wrote:
>
> > See [1].
> >
> > [1] https://www.w3.org/wiki/TTML/CodecsRegistry
>
> Dave Singer
>
> singer@mac.com <javascript:;>
>
>
>
>