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Re: DFXP 1.0 Last Call issues list

From: Glenn Adams <gadams@xfsi.com>
Date: Sat, 12 Sep 2009 02:53:37 -0400
Message-ID: <94ad087a0909112353y2b4a03beq612b69f55137b7f8@mail.gmail.com>
To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Cc: Philippe Le Hegaret <plh@w3.org>, public-tt@w3.org, daniel.weck@gmail.com, werner.bailer@joanneum.at, Gur@captionsinc.com
inline below ([GA])

On Sat, Sep 12, 2009 at 1:06 AM, Silvia Pfeiffer

> Hi all,
> Most of my feedback has been addressed.
> Here is a short list of things that I think can still be improved.
> However, I do not think any of this should stand in the way of moving the
> specification to CR.
> 1. ttp:clockMode
> There is still no example on what a specification that uses gps, utc and
> local values would look like.
> I am particularly worreid about the GPS time coordinates, for which the
> format is not defined anywhere - not even in the given reference for GPS -
> only when I do a bit of a search, I find
> http://tycho.usno.navy.mil/usno_head.html , but that format seems not to
> fit with the rough description given in DFXP as:
> "The primary difference between GPS time and UTC time is that GPS time is
> not adjusted for leap seconds, while UTC time is adjusted as follows: UTC =
> TAI (*Temp Atomique International*) + *leap seconds accumulated since 1972
> *. TAI is maintained by the *Bureau International des Poids et Mesures*(BIPM) in Sevres, France. The GPS system time is steered to a Master Clock
> (MC) at the US Naval Observatory which is kept within a close but
> unspecified tolerance of TAI."
> Maybe it makes sense to remove the gps specification, since it's not
> expected to be substantially different to UTC and since not specifying the
> format properly will mean we won't get interoperable implementations of this
> feature. However, I am not too fussed about leaving it in - it just won't
> get used then.

[GA] GPS based time codes are used in US DTV broadcasts for PSIP, which is
the format of transmitting program event (i.e., EPG) related data; the
normative reference to the US Navy Observatory site is sufficient for anyone
to ascertain the differences between UTC and GPS time codes;

since most of the world's aviation and naval industry is satisfied with the
definition of GPS time codes, you should be as well, and I leave it to you
(the reader) to research yourself sufficiently the difference between the
two, which is well captured by the description given in DFXP;

2. Other requested examples as per
> http://www.w3.org/2009/09/dfxp-lc-issues.html
>  and
> http://lists.w3.org/Archives/Public/public-tt/2009Jun/0020.html
> would be helpful to add, but are not urgent, since they don't fundamentally
> change the spec.

[GA] I agree it may be helpful, but it is strictly informative, so is not
strictly necessary. Furthermore, nobody is volunteering to create these
examples (are you?).

> 3. Section ordering
> http://lists.w3.org/Archives/Public/public-tt/2009Jun/0028.html
> I am not overly fussed about, though I think the concrete suggestions I
> made would be trivial to execute and would improve the readability.
[GA] I'm afraid you underestimate the editorial work involved to do this
reordering, and it adds nothing to the technical content of the document.

> 4. Use of external metadata
> http://lists.w3.org/Archives/Public/public-tt/2009Jun/0034.html
> I may be blind, but I cannot see an example of foreign namespace metadata
> from Dublin Core added in 12.1.1 of http://www.w3.org/TR/ttaf1-dfxp/, see
> ISSUE-137.

[GA] You are looking at the wrong version of DFXP. Look at at the current
editor's update at:


look specifically at the last example in 12.1.1 "Example Fragment - Foreign
Element Metadata".


> Best Regards,
> Silvia.
> On Sat, Sep 12, 2009 at 12:15 PM, Silvia Pfeiffer <
> silviapfeiffer1@gmail.com> wrote:
>> Getting onto it now - hope there is still time.
>> Will give you feedback asap.
>> Thanks,
>> Silvia.
>> On Sat, Sep 12, 2009 at 12:33 AM, Philippe Le Hegaret <plh@w3.org> wrote:
>>> ... is at
>>>  http://www.w3.org/2009/09/dfxp-lc-issues.html
>>> I'm trying to close the loop with Silvia on some of her issues. Besides
>>> that, I believe we'll be all set to move to CR. If you believe I'm
>>> missing something, please let me know.
>>> Philippe
Received on Saturday, 12 September 2009 06:54:26 UTC

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