{Minutes} TTWG Meeting 2019-04-25

Thanks all for attending today’s TTWG meeting. Minutes can be found in HTML format at https://www.w3.org/2019/04/25-tt-minutes.html

In text format:


   [1]W3C

      [1] http://www.w3.org/

                Timed Text Working Group Teleconference

25 Apr 2019

   [2]Agenda

      [2] https://github.com/w3c/ttwg/issues/34

   See also: [3]IRC log

      [3] https://www.w3.org/2019/04/25-tt-irc

Attendees

   Present
          Nigel, Cyril, Gary, Andreas, Pierre, Nigel, Glenn,
          Thierry, plh

   Regrets

   Chair
          Nigel

   Scribe
          Cyril, nigel

Contents

     * [4]Topics
         1. [5]this meeting
         2. [6]TTWG Charter
         3. [7]WebVTT Implementation Report
         4. [8]TTML2 and TTML3 Pull Requests
         5. [9]Add IMSC profile designators to Table 5-2.
            ttml2#1034
         6. [10]Character-related style properties should not
            apply to ruby containers. ttml2#1043
         7. [11]Profile Registry
         8. [12]AOB
         9. [13]Meeting Close
     * [14]Summary of Action Items
     * [15]Summary of Resolutions
     __________________________________________________________

   <cyril> scribe: Cyril

this meeting

   nigel: I've put the charter but not sure there is anything to
   discuss
   ... WebVTT IR is important of course
   ... 2 issues marked for Agenda on TTML2
   ... and one issue on the profile registry
   ... I've just added an AOB about an Accessibility Event in
   June, it's a notification
   ... anything AOB missing?

TTWG Charter

   nigel: the status is that we'll ask to be sent for AC review
   end of next week
   ... by that point we should have explainers

   thierry: was it presented to w3m?
   ... before going to AC it should be validate by w3m

   nigel: the issues was apply the correct list of chairs,
   something about webvtt
   ... it's my expectation that it will need some validation first
   ... any comment on the current draft charter

   atai2: regarding the explainers?
   ... I haven't been at the meeting where explainers were
   discussed
   ... I updated the requirements for 360 subs
   ... my conclusion is that I don't expect that we'll publish
   something this year
   ... discussions are needed to scope this area and write
   requirements
   ... I will not be able to write explainers soon

   nigel: as the leader of this activity, if you say we'll need to
   defer this, I'm fine

   atai2: the charter is not only covering 2019, up to 2021

   nigel: yes but the requirements agreed were for this year

   atai2: I just wanted to know if it is ok to delay the explainer
   until we have better scope

   nigel: we have received an incoming liaison from MPEG
   ... if we defer will there be an impact on these industry
   timelines
   ... will we miss the 'right' time to publish something in TTML?

   atai2: I don't think we'll be able to deliver something final
   for this activity in 2019

   plh: I forwarded an email on monday
   ... and I will forward another one

   glenn: I reviewed the document this morning
   ... and it's relevant
   ... for timed text

   nigel: thanks for looking at that

   glenn: it basically provides an out of band mechanism for
   associating a timed text region with a 360 region

   atai2: MPEG's document is member confidential

   plh: there are 2 documents: the PDF liaison
   ... and the real meat is the 2 technical documents referenced
   ... and they are ISO confidential
   ... as long as we don't copy these documents here we're fine

   nigel: I agree minutes are fine

   cyril: discussing documents, minuting this discussion, is fine

   nigel: andreas do you think it's still best to defer that piece
   of work, in this group, until 2020

   atai2: we should discuss MPEG's document in the group and see
   what our input can be and see from there
   ... there is not only ISO/MPEG but the Web Community Group
   ... I still would like to postpone it
   ... but I'm also ok to postpone the decision to postpone
   ... it does not make sense for me right now to produce an
   explainer

   glenn: presumably, this work will be published in a separate
   module
   ... so it can have it's own timeline
   ... and the charter is not explicit about it
   ... putting end of 2019 as a hard date of all possible
   rec-track documents is probably not a good idea
   ... we should focus on TTML2 2nd edition and TTML3
   ... and the modules that we do finish by the end of the year

   ack

   nigel: I sent a little summary of explainers to people involved
   ... anything else on the charter?
   ... for philippe, at the end of next it will be taken by staff
   for management review

   plh: yes, that will take us 3 to 4 weeks
   ... it may take less but I cannot guarantee that
   ... will need horizontal review ...
   ... I can even circulate it asap if you like to
   ... it doesn''t have to be 100% final

   nigel: you can do that
   ... I think the remaining issues are PLH to address

WebVTT Implementation Report

   nigel: what's the status?

   gkatsev: unfortunately, not much time
   ... we're missing 2 tests: vertical and text combine
   ... adding should be easy and I should have some time
   ... also working with Eric to fix display of vertical cues in
   Safari so that can pass
   ... text combine, it seems that no browsers support it yet
   ... not sure what to do about that

   <plh> [16]https://github.com/w3c/webvtt/issues

     [16] https://github.com/w3c/webvtt/issues

   <nigel> plh

   plh: there are still some issues not classified in the WebVTT
   repo
   ... it would be nice if they are to remain open until the next
   version
   ... we should make the decision as a WG to move the spec to PR
   ... either starting the CfC next week or the week after
   ... we published the updated CR on April 4th

   <nigel> nigel

   plh: and unless someone has an issue, we should move ahead

   nigel: for me, that is dependent on the IR being ready
   ... until we have that, we cannot have the CfC

   plh: when can we have the IR ready

   gkatsev: I already have the spreadsheet
   ... what would be necessary?

   nigel: we need to have good understanding that the test set is
   complete
   ... and we create some document describing the set

   plh: if we have the spreadsheeet ...

   nigel: it might be enough

   gkatsev: I can model WebVTT's IR based on the spreadsheet to
   look like IMSC's IR

   <nigel> [17]IMSC 1 IR

     [17] https://www.w3.org/wiki/TimedText/IMSC1_Implementation_Report

   plh: that page needs to contain information that cannot go in
   the spreadsheet
   ... the criteria is 2 implementations of every feature
   ... but this is open to interpretation, depending on whether
   the test is corner case or not
   ... the tests may not represents an entire feature, if it
   fails, it may be ok if it is a corner case

   gkatsev: I can think of one, right now, font-variant
   ... CSS as a feature is validated but some CSS properties,
   white listed, are not supported

   nigel: we should actually test that non white listed properties
   are ignored
   ... there is a must for that
   ... and it's important
   ... we need just one example of a property that is not white
   listed and see that it is ignored

   plh: I agree

   gkatsev: font-variant is white listed as part of the font
   shorthand

   plh: is the test testing as part of the shorthand?
   ... one way to solve this is to check with the CSS WG the
   status of this
   ... and see if Chrome considers this as a bug
   ... or if relying on it is dangerous
   ... and in the latter case, putting a note in the spec about it
   ... or if another approach is needed
   ... gary if you identify other such properties
   ... let me know
   ... I can take the action to check with CSS about these
   properties

   gkatsev: I'll take a look at them, and they might be
   implemented as vendor-prefixed

   plh: if it goes in even more details, like units, we might have
   to go into more details too

   nigel: so there is still some work to do to provide the IR,
   before we can issue the CfC
   ... anything else?

   plh: for the purpose of the charter, I'd like to understand
   what the group thinks
   ... it looks like we could publish CR
   ... and in that case it should be in the charter
   ... if you are not ok with that, you should speak about it

   nigel: for charter, we need to have adequate participation,
   chair and strategy review

   plh: we need to know who is going to maintain?
   ... and if part of the charter, it needs to be TTWG?

   pal: the only question mark in the charter was chairing that
   ... gary has been active, so we have editing resources
   ... but the chairing part is not clear

   plh: I don't think the chairing part is going to be difficult

   pal: the charter has a TBD

   plh: and I have an action on that
   ... either I convince Nigel or I need to convince someone else

   gkatsev: I want to see this through so I might step up if
   needed

   plh: reach out to me directly if you want to discuss this

TTML2 and TTML3 Pull Requests

   nigel: 2 issues

Add IMSC profile designators to Table 5-2. ttml2#1034

   <nigel> github: [18]https://github.com/w3c/ttml2/issues/1034

     [18] https://github.com/w3c/ttml2/issues/1034

   glenn: I reviewd that and the suggested approach looks
   reasonable to me and I will prepare a PR

   nigel: thank you, done, then

Character-related style properties should not apply to ruby
containers. ttml2#1043

   <nigel> github: [19]https://github.com/w3c/ttml2/issues/1043

     [19] https://github.com/w3c/ttml2/issues/1043

   glenn: on this one I posted a PR and haven't got a review

   pal: I reviewed it and proposed an alternative PR

   glenn: I'll take a look at that

   pal: my main question is really: does that match your
   understanding?
   ... my alternate PR want to be extremely explicit to see if we
   agree

   glenn: you want to address the possible ambiguity of white
   space preserve
   ... in anonymous text spans as children of these containers
   ... I hate dealing with dueling PR

   pal: you raised an interesting point
   ... another dimension of the issue is XML space
   ... and applicability, this is not a style property
   ... my alternative PR does not address that, so maybe we need
   to merge both PR

   nigel: on the point of XML space preserve, a naive
   interpretation means that there is character content

   glenn: basically, we don't want it to be
   ... it was never the intention that the text content of
   containers would be treated as text
   ...glenn: so I tweaked that in my PR
   ... another thing to keep in mind is that text nodes in
   containers will be wrapped in anonymous span, so there is no
   more character content directly in the container

   pal: I had not considered that when I filed the ticket
   ... maybe the 2 PRs are complementary
   ... nigel, what's your take on the white space issue?

   nigel: glenn's PR says that it ignores it
   ... my comment is broader, it's about any text, not white space

   glenn: there are already rules that rule out non-whitespace
   character
   ... are you asking about what happens when the content is
   invalid?

   nigel: yes

   glenn: in many cases, we don't specify what happens in case of
   error
   ... if you are a validating processor, you could reject

   nigel: I can see why you have the explicit exception about
   linear white space

   glenn: at that time I had not realized the ambiguity about
   preserve
   ... I want to reiterate
   ... since there are no character content that can appear as a
   child of container
   ... my original statement was that we don't need to say
   anything
   ... that's when he introduced the ambiguity about white space
   ... and since that is addressed, I think we don't need to say
   anything about properties that apply to character content
   ... that's why I don't think we need to put special case in
   each property for this

   nigel: but they do apply for inheritance

   glenn: right
   ... I pointed that out in the note

   pal: but inheritance is not application

   glenn: right, application means semantic application

   pal: like font-size does not apply to region
   ... my PR is to make it more explicit
   ... I do have a question about audio properties

   glenn: I do not like the approach of putting special case
   language in each property

   pal: you should consider the amount of change
   ... there's already special cases

   glenn: having repetition of the same statement in many
   properties is not a good thing

   summary: we'll continue reviewing the PR offline to reach
   consensus

Profile Registry

   glenn: we agreed in prior meetings to go ahead and publish
   ... I need directions on how to do that

   nigel: it's published

   glenn: excellent

AOB

   <inserted> scribe: nigel

   Nigel: I just wanted to mention for information that I've been
   invited to speak about W3C accessibility stuff at an ITU
   ... event in Geneva on June 7, and plan to attend and do that.
   There's a link to the event in the agenda - if you want to
   ... discuss this any more please get in touch with me offline.

Meeting Close

   Nigel: Thanks all, we didn't have time to discuss the TTML
   Profile Registry issue so defer that until next week.
   ... I'll look at the load for next week and decide 1 or 2
   hours, but please let me know if you have additional topics by
   Tuesday so I can schedule it. [adjourns meeting]

Summary of Action Items

Summary of Resolutions

   [End of minutes]
     __________________________________________________________


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