Re: Need Update to TTML1 Errata

On Thu, Jul 17, 2014 at 9:52 AM, Nigel Megitt <nigel.megitt@bbc.co.uk>
wrote:

>  This is (mostly*) dependent on us closing Issue-259, which is dependent
> on Pierre's review, as agreed in our meeting this afternoon. Others are at
> liberty to review and comment too of course.
>
>  So we should not put these errata to TR until Issue-259 is closed. When
> it has been closed I'm happy for these errata to be considered part of the
> solution to Issue-259 and push through ASAP after that. ASAP here is >= 10
> days after resolution of Issue-259 as per our charter.
>
>  * By the way I didn't expect the use of zero duration to be permitted
> via this errata document since it is a substantive change rather than a
> clarification. Is there a pressing reason why it needs to be in TTML 1 and
> can't wait until TTML 2?
>

I don't view it as a substantive change but rather a failure to document
expected usage and prior intention. For example, we have:

The *Root Temporal Extent*, i.e., the time interval over which a *Document
> Instance* is active, has an implicit duration that is equal to the
> implicit duration of the body element of the document, if the body element
> is present, or zero, if the body element is absent.


... if the anonymous span's parent time container is a sequential time
> container, then the implicit duration is equivalent to zero


Further, syntactically, dur was defined to be a <timeExpression> which
clearly allows dur="0s".

So we are really just clarifying a pre-existing state: that we allow a
duration of value 0.


>
>  Kind regards,
>
>  Nigel
>
>
>   On 17/07/2014 16:26, "Glenn Adams" <glenn@skynav.com> wrote:
>
>   I have been updating the TTML1 Errata document in the repository [1],
> and now have three additional items (see those marked as "published
> 2014-07-17). We need to push these errata through to the TR page [2].
>
>  I would like for either (1) Thierry to push these to TR ASAP, or (2)
> defer the push until we discuss in a teleconference. Nigel, please
> recommend an approach.
>
>  [1]
> https://dvcs.w3.org/hg/ttml/raw-file/default/ttml1/spec/ttml1-errata.html
> [2] http://www.w3.org/2013/09/ttml1-errata.html
>
>