See also: IRC log
<scribe> scribe: nigel
Nigel: We have TPAC, IMSC, TTML, I don't know if we will cover WebVTT and HDR in PNG.
Glenn: I can only stay for 1 hour
today, so TTML first would be better. Same will be true
... throughout July and early August.
Nigel: I'm not going to be
present on 17th and 24th August.
... Any other business or specific points anyone wants to make
sure we cover?
group: [silence]
Pierre: I only have about 1 hour today.
Nigel: We have to think about
next steps for TTML - we have comms for the wide review,
... TTML1 3rd Ed. perhaps and continuing on the open issues on
TTML2.
Glenn: It was good to see
Thierry's draft call for wide review. I'm going to read that
and
... maybe suggest a summary of changes since TTML1.
Thierry: +1
Nigel: +1. I think I've already
done it and we've discussed it Glenn. but I haven't found it
yet.
... I'll take the action to find that and add it to the
text.
Glenn: My focus on TTML now is to
resolve the outstanding issues including the previous
... issues reported by Richard. The ones that predated
Richard's comments I'm probably
... going to prioritise a little higher since they have been
lingering for a while. The TTML1
... - some of the issues on TTML2 require resolving TTML1
issues so they will naturally get
... addressed in that process too, mostly. A few months back I
had already tweaked the TTML1
<tmichel> In addition to the features introduced in IMSC1 and generally refining TTML1 features, it adds support for East Asian languages, enables stereoscopic 3D, and details the mapping to HTML and CSS. Glenn Adams (Skynav) is the editor of TTML2.
<tmichel> https://www.w3.org/2016/01/emmyawardttml.html.en
Glenn: ED in GitHub to make use
of the new format, and I had put some effort into preparing
that.
... The current ED of TTML1 says 3rd Ed. and is mainly in the
new format, maybe needs
... some more tweaking.
Nigel: As far as I recall we
agreed the approach to all the TTML1 issues, so it should
be
... straightforward to process them.
Glenn: Yes the only one I need to look at is the one raised by Pierre about region resolution.
<inserted> Ambiguous definition for determination of descendant region identifier. #194
Glenn: I need to convince myself that it won't break anything.
Pierre: This is what happens if you associate say a div with region1 and a child p with region2.
Nigel: Thank you!
... OK that sounds like it needs some more thought before we
can discuss it.
... Going back to the comms on TTML2.
... Thierry, you just posted some text above - was there
more?
<tmichel> https://www.w3.org/AudioVideo/TT/docs/TTML-Profiles.html
Thierry: We drafted this for the Emmy press release, and there's something in the page linked above.
Nigel: I'm pretty sure Glenn and I worked on some wording, I need to go and find it.
Thierry: I recall that, but it looks like it didn't go into the spec, that paragraph.
Nigel: Okay I'll do some archaeology.
Glenn: We added the subsection that enumerates the high level syntactic changes.
Thierry: If I recall, it was after TPAC 2016.
Nigel: If everyone could read
Thierry's draft and feed back on the reflector that would be
helpful.
... Are there any groups to whom we need to customise our
message?
... For example SMPTE. If a general message works that would be
good.
Glenn: I think we should use a general message.
Mike: I can't off the top of my head think of any specific messages for particular organisations.
Nigel: Thierry, when we've agreed
this text please could you send those out based on the
... liaison addressees we used for IMSC 1.0.1 which were all
BCCed to member-tt and CCed
... to team-liaisons?
Thierry: Yes, will do.
Nigel: Thank you
Thierry: I'll wait for the go-ahead on the final text.
Nigel: By the way, for the
minutes I want to note that we published the WD for WR on June
30.
... Thanks Glenn for making the last changes to get that out by
our deadline.
Nigel: Glenn, are you going to work on TTML1 3rd Ed first as a precursor to TTML2?
Glenn: That wasn't my plan
specifically, it's mainly to knock off the TTML2 issues, some
of
... which involves resolving TTML1 issues in 1 3rd Ed. I'll be
driven by TTML2 issues rather
... than TTML1 issues.
... In the next 2-3 months I intend to make good progress on
both fronts.
Nigel: And the next thing we'll
need thinking ahead to CR is some exit criteria and test
... suites.
Glenn: The issue of creating a
formal test suite for TTML2 is something we haven't
really
... taken up yet.
Nigel: True, I just want to flag
up that we will need it.
... We also will need to think about implementations - our work
implementing the audio
... features is going well so we may be able to generate some
test material for that too.
Nigel: I just want to raise that
we noticed a couple of things that need fixing in the HDR
appendix
... so I just opened an issue and a pull request.
Remove HLG HDR step 8 superscript 5b #398
Error in HLG HDR appendix step 8 #397
Nigel: I also made some
formatting changes to put mathematical expressions in code
blocks
... rather than just body text.
... I've assigned Pierre as a reviewer there, though obviously
anyone might want to look.
... I think I've taken an action from someone outside the group
to feed in a point about
... quantisation in the PQ section, which needs to use narrow
range signal not full range.
Pierre: I've not heard that feedback before.
Nigel: Ok I'll raise the issue then.
Nigel: Thierry please could you explain about the transition to CR?
Thierry: I have sent the
transition request to the Director CC plh last Friday and I
was
... expecting a response on Friday or Monday but on Monday I
got the response that they
... had not had the time to process the transition request - to
do with 4th July and the EME
... work, so Philippe said he would give us a response
tomorrow. Depending on the time
... I get the response it will be published on Tuesday or
Thursday, because I need to send
... it to the Webmaster 2 days in advance. That's very
unfortunate because it seemed like an
... easy decision, with very few comments, but I can't do much
about it.
... Everything was ready, the spec is already in TR.
Nigel: Do we have to edit the spec due to the publication date change?
Thierry: Yes I will have to move
it to the final destination and then change the end date
... of the CR, from Aug 6 to whatever it is, 11th or 13th, as
well as the publication date on
... the top of the document.
... It's pending an email from plh now, and I'll let you know
as soon as there is a response.
Pierre: Thierry, if you can let
me know the exact changes made to /TR so I can reflect
them
... in the Editor's draft please?
Thierry: 3 things: the URI, the pub date and the end of review date.
Pierre: I understand, just let me
know the new values and I'll reflect it.
... I try to keep GitHub matching exactly what is
published.
Thierry: I will, I'm sorry about that.
Nigel: The other thing I wanted
to raise on IMSC 2 is that we need to start thinking
about
... the scope and requirements of IMSC 2 so we know what it
will look like, and maybe
... publish something with a time-limited review period so that
we can make sure all the
... inputs are gathered and we have something like a
requirements document to refer to.
Pierre: I've begun working on this and there's the wiki page also.
Nigel: Great, thank you.
Nigel: I think there's been some progress here.
Pierre: I've not had time to process Chris's feedback.
Nigel: Understood. It looks
mostly positive, so it may allow us to release the block
on
... publishing the note.
Nigel: David's obviously not on
the call, but just to reiterate that there is a request for the
WG
... to review and hopefully approve the CG's dispositions.
action-497?
<trackbot> action-497 -- Nigel Megitt to Invite csswg to joint meeting at tpac 2017, with list of topics. -- due 2017-06-15 -- OPEN
<trackbot> http://www.w3.org/AudioVideo/TT/tracker/actions/497
Nigel: I began to look at this
and yet again, with apologies Dae, I failed to find the list
of
... CSS issues we want to discuss, that you put together
Dae.
Dae: Is it the IMSC 2 wiki page?
TTML2 features for inclusion in IMSC2
Dae: I edited it to add my transform proposals, in #218
First Pass at IMSC2 to CSS Fallback #218
Nigel: Ah ok thank you.
... One of my motivations for raising this aside from the issue
is that the TAG offered
... to assist with facilitating the meeting with CSSWG and they
are coming to London in a
... few weeks, so I plan to meet them then and hope to discuss
this general issue, of CSS
... support for styling needed for subtitles and
captions.
... I'll collate this information ahead of that meeting and
send it through.
... Dae, your helpful comment on imsc#218 is dependent on
ttml2#254 and ttml2#240.
... Now that ttml2#240 is closed do you want to have a look at
the impact on textEmphasis?
Dae: Sure.
Nigel: Since we did that back in
March we have added fillLineGap so that obviously needs
... to be added.
Pierre: Also linePadding and multiRowAlign, neither of which is supported by CSS.
Nigel: Thank you!
Pierre: Also I'm going to post a link to a question posed by Tab Atkins to the CSS mailing list back in 2015:
<pal> https://lists.w3.org/Archives/Public/www-style/2015Sep/0077.html
Pierre: I've never seen it
answered and I think it's relevant because it deals with the
inner workings
... of XSL-FO and CSS.
... There's some interesting behaviour, where UAs seem to
behave differently from the spec.
... It's been a real issue to deal with this.
... It's related to whitespace collapse and deletions before
line breaks. UAs treate line breaks
... very differently depending on if they occur because of a
<br> or a linefeed character.
... I ran into it but it looks like Tab Atkins ran into it
earlier. It deals with the basic processing
... in CSS and also impacts TTML.
... In a nutshell, if you put a space before a <br>
specifically in a span that is a sibling of a br,
... then that space does not get removed.
... Chrome does not delete that space for instance.
Glenn: The only way you know if it is there is if there's some border or background?
Pierre: Exactly.
Glenn: I'm pretty sure XSL-FO
would need that space to be deleted at the end of the
line
... for the purpose of backgrounds etc... Hmm maybe!
Pierre: Here's the codepen:
<pal> https://codepen.io/palemieux/pen/PjeKyq
Pierre: The space being visible
or not can affect line height and have other weird
effects.
... The reason it is a bug is pretty obvious - if the space is
outside the span, as a node between
... the sibling span and the br then it is deleted. So the
whitespace removal algorithm might
... be dumb and operate before the entire line is built.
Glenn: I remember seeing this
before and other people have recognised there's some
... subtlety here. Firefox does not put the space in.
Pierre: And Edge does.
Glenn: Firefox tried to do what IE did so I guess IE did it the way Firefox does it now.
Pierre: From the CSS spec I see
no reason why the space should be retained. From an XSL
... and a CSS perspective it should make no difference if the
space is in or out of a span.
Glenn: I agree, unless it were a
non breaking space or an em space or something. Regular
... white space should not appear.
Pierre: To complicate this,
Andreas has been running test suites based on XSL
processors
... and at least in the processor he has used that space does
show up.
Glenn: I can see why this might
be a problem when you are trying to get HTML/CSS to
render
... linePadding for example.
Pierre: Or anything with a background.
Nigel: I'll gather the existing
stuff together and figure out where to put it then share
it
... for review before sending it to TAG and CSSWG.
... Thierry please could you create a TPAC wiki page like we
have had in previous years?
Thierry: Yes, add an action please.
<scribe> ACTION: Thierry Create a TTWG wiki page like in previous years [recorded in http://www.w3.org/2017/07/06-tt-minutes.html#action01]
<trackbot> Created ACTION-499 - Create a ttwg wiki page like in previous years [on Thierry Michel - due 2017-07-13].
Nigel: Okay, we've covered all our agenda points, so let's adjourn. Thanks everyone! [adjourns meeting]