Re: {Minutes} TTWG Teleconference 2024-11-21

Update on the resolution to request transition of DAPT to CR: I rebased w3c/dapt#269<https://github.com/w3c/dapt/pull/269> and updated the CR end date as discussed, so the branch for that draft pull request is ready to be considered the basis for the CR.

Nigel


From: Nigel Megitt <nigel.megitt@bbc.co.uk>
Date: Thursday 21 November 2024 at 17:31
To: "public-tt@w3.org" <public-tt@w3.org>
Subject: {Minutes} TTWG Teleconference 2024-11-21
Resent from: <public-tt@w3.org>
Resent date: Thursday 21 November 2024 at 17:30

Thanks all for attending today’s TTWG meeting. Minutes can be found in HTML format at https://www.w3.org/2024/11/21-tt-minutes.html


We made one resolution:

RESOLUTION<https://www.w3.org/2024/11/21-tt-minutes.html#0485>: Request transition to CR based on w3c/dapt#269<https://github.com/w3c/dapt/pull/269> (after rebasing)

Since this is a resolution made as a result of a Call for Consensus process our Decision Review period has concluded.

Those minutes in plain text:

   [1]W3C

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


                Timed Text Working Group Teleconference

21 November 2024

   [2]Previous meeting. [3]Agenda. [4]IRC log.

      [2] https://www.w3.org/2024/11/07-tt-minutes.html

      [3] https://github.com/w3c/ttwg/issues/295

      [4] https://www.w3.org/2024/11/21-tt-irc


Attendees

   Present
          Andreas, Atsushi, Chris, Chris., Cyril, Gary, Matt,
          Nigel

   Regrets
          Pierre

   Chair
          Gary, Nigel

   Scribe
          nigel, cpn

Contents

    1. [5]This meeting
    2. [6]DAPT
         1. [7]Implementation Report
         2. [8]Pull requests
         3. [9]CFC Results and CR next steps
    3. [10]TTML2 - outdated banner
    4. [11]Charter 2025
    5. [12]AOB - Web Video Map Tracks (WebVMT)
    6. [13]Meeting Close
    7. [14]Summary of resolutions

Meeting minutes

  This meeting

   Nigel: DAPT, minor TTML2 update, Charter 2025, anything else?

   Chris: AOB around the WebVideo Map Tracks (WebVMT)

  DAPT

    Implementation Report

   Nigel: I have created a wiki page

   [15]DAPT Implementation Report

     [15] https://www.w3.org/wiki/TimedText/DAPT_Implementation_Report


   Nigel: It's a starting point. I've copied in the draft CR exit
   criteria and created a template based on what we did before
   … It lists the extension features from DAPT, we can assess
   implementations based on tests for each feature

   Cyril: This is looking good. How do we test features that are
   prohibited?
   … I think #source-data as example

   Nigel: We can create a document that does what you're not
   allowed to do, and check a validation implementation fails on
   it
   … and a document that does it the right way, check it passes
   validation. Is that enough?
   … The alternative is to rework the extensions so they're
   expressed as prohibitions. Equally weird, but testable

   Cyril: Either way, not every type of processor can recognise
   that, it has to be a validation processor. So to exit CR we
   need a validation processor, not just an authoring tool and a
   presentation processor
   … What kinds of processors do we need to include in the
   implementation report?

   Nigel: (Reads the requirements in the Charter)
   … You could have a content producing implementation that does
   source-data the right way, but it's a pretty weak test. Show
   the content it generates is valid, without using a validation
   processor itself, use manual inspection
   … Any suggestions?

   Cyril: A validation tool based on the XML schema, could be the
   easiest way to validate this feature
   … I'd like to understand which features we think will be
   difficult to pass, because we'll have two implementations,
   specifically for features marked at-risk, e.g., variants around
   audio source

   Nigel: The at-risk features are all things that are part of
   TTML2 already. With the way the CR exit criteria are drafted,
   and the list of features in the test list, none of the at-risk
   features are listed
   … I'm not sure we have specific sub-features or extensions.
   Script Event Grouping is an example.
   … We might find nobody wants to implement that, so we'd have to
   remove support for it, would be a significant editorial change

   Cyril: I think it's good enough for now

   Nigel: The BBC and Netflix implementations are just listed as
   examples

   Cyril: It would be good to encourage people to list their
   implementations, even partial ones

   Nigel: Yes, e.g, the EBU EuroVox
   … The moment to do that is when we publish CR, announce and ask
   for implementation details
   … We need the report to exit CR, not enter CR

   Nigel: Anything else on this topic?

   (nothing)

    Pull requests

   Nigel: There are three PRs. Only one is required for CR, the
   work on feature dispositions
   … Thank you Andreas for your positive review. Does anyone want
   more time for review before I merge?

   Cyril: I don't need more time

   Andreas: It does need some time to look at, there's a couple of
   features

   Nigel: Andreas and I have looked carefully at it. I'm
   comfortable merging it, we have no requested changes, and
   enough time has passed

   Cyril: I'm fine with merging it

   Nigel: There's an editorial PR to add an XSD, and there's
   another to prepare for CRS that needs rebasing

    CFC Results and CR next steps

   Nigel: Any objection to declaring that we have consensus?

   Cyril: I support

   Andreas: Also fine with me

   RESOLUTION: Request transition to CR based on [16]w3c/dapt#269
   (after rebasing)

     [16] https://github.com/w3c/dapt/pull/269


   Nigel: Atsushi, you raised this for horizontal review

   Atsushi: I'm asking for security review. I hope to hear back
   shortly

   Chris: It's not a recharter, it's a new group. I'd concur not
   to block on it.

   Atsushi: Usually the review is required, but we should be fine
   for asking transition

   Nigel: Is there anything else you need from the WG to request
   transition?

   Atsushi: No, I'm just waiting to hear back from horizontal
   reviews.
   … There's no strict procedure on requesting review and CR
   transition

   Nigel: I might need to adjust the expected PR date in the CRS.
   Any suggestions for a date to use?

   Atsushi: I personally want to finish during December, before
   end of year

   Nigel: I want to suggest changing it to 31 Jan
   … I'll do that

   Nigel: There's a pull request to add an XSD to the repo, which
   I created with help from Ben Poor from EuroVox
   … It tries to validate some of the prohibitions and
   constraints, in DAPT not in TTML
   … It pulls in the EBU-TT Metadata XSD via a git submodule
   … It's there for review and try out to see if it works
   … The IMSC XSD just references from TTML2 and SMPTE-TT and
   others. The idea is you set up the validation environment to
   know where those XSDs are
   … Getting that to work in my experience is difficult for
   implementations
   … So the approach I used for DAPT is to create one XSD
   … Hopefully that's easier to use

   Andreas: Are you using XSD 1.0 or 1.1?

   Nigel: It's 1.0, easier to get tooling that works with it

  TTML2 - outdated banner

   Nigel: The banner now points to the most recent version, as
   requested
   … Thanks to Atsushi and systeam

  Charter 2025

   Nigel: I drafted the charter

   github: [17]w3c/charter-timed-text#89

     [17] https://github.com/w3c/charter-timed-text/issues/89


   github: [18]w3c/charter-timed-text#89

     [18] https://github.com/w3c/charter-timed-text/pull/89


   Nigel: I've incremented the date by +2 years. I've adjusted the
   wording around teleconferences
   … I added mention of historical applications of TTML2
   … I fixed links, e.g., to the current Process
   … I added IMSC 1.3, reusing wording from previous editions
   … I added DAPT, and mention that it defines registries
   … TTML2 stays the same
   … I added ARIB as an external organisation
   … I haven't updated the charter history section
   … Please review and comment on the pull request
   … Any questions?

   (nothing)

   Nigel: We'll submit around the end of January?

   Atsushi: We need to send advance notice, so I'll file a
   strategy issue in mid-December to highlight the charter
   discussion

   Nigel: That's perfect, thank you.

   Nigel: Anything anyone wants to raise about the charter?

   (nothing)

  AOB - Web Video Map Tracks (WebVMT)

   Chris: This is another Charter out for AC review.
   … I'm here as an AC Rep reviewing the Charter.
   … It's the Spatial Data on the Web WG
   … One of the specs listed as in scope for potential maintenance
   is the WebVMT spec.
   … My question to you is whether you want this WG to be listed
   under the coordination
   … section for that WG given that they're basing work on WebVTT.
   … They don't list TTWG as coordination at the moment.
   … Would you want to see that, and if so, I'll mention it in the
   AC Review.

   Gary: I don't see an issue with having TTWG listed,
   … but at the same time, it's clearly been working fine as is so
   … I don't think we necessarily should make the change to
   disapprove not having it.
   … Last time they needed a discussion we had that, and agreed no
   change to WebVTT on that occasion.
   … Not having it listed is not a blocker on anything [i.e. the
   groups talking to each other]

   Chris: As you say, it's fine to leave it as-is in coordination.

   Gary: It could be "if you're making other changes feel free to
   add it but otherwise don't worry"

   Chris: I could say that and leave it to their discretion.

   Nigel: Would they prefer to have closer alignment and higher
   compatibility between the specs. At the moment it looks like
   WebVMT is inspired by WebVTT

   Gary: WebVMT documents may not be valid WebVTT, e.g., by using
   the missing end time feature

   Nigel: Is that something W3C should maintain as a constraint on
   these specs?

   Gary: Maybe long term, it's not needed. If the formats diverge
   based on their needs, that's probably fine

   Nigel: OTOH, if they think of some new spec change, we'd
   hopefully discuss as both groups might want it in their specs
   … I think the purpose of coordination is to have a list of
   groups to be consulted when there's a significant change
   … We don't list them in our charter coordination list. But i
   think it should be symmetrical

   Atsushi: There are several meaning for the list: from just
   being interested, to having a more formal relationship
   … It seems to me some W3C groups are listed as just being
   interested. Not sure on the formality of this section
   … Not sure the Process needs a strict definition, just
   guidelines. It wouldn't factor too strongly in the team's
   review

   Nigel: Another consideration relates to immersive captions. If
   we decide to work on adding 3D coordinates into caption
   formats, it relates to that group's use cases
   … While we aren't doing volumetric subtitles and captions, it
   has come up before and could again

   Andreas: We discussed maybe 4 or 5 years ago, things in the
   market might have changed now
   … Could be a requirement for us

   Chris: I think it's worth suggesting to them that TTWG is
   listed, without proposing a tight collaboration.
   … More a "keep us informed", and as a reminder as much as
   anything to come back to this group
   … should they have particular changes that might be worth
   including in both specs.

  Meeting Close

   Nigel: Thank you for scribing, Chris, we're 5 minutes over,
   let's adjourn.
   … See you in 2 weeks everyone!
   … [adjourns meeting]

Summary of resolutions

    1. [19]Request transition to CR based on w3c/dapt#269 (after
       rebasing)


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