{Minutes} Audio Description Community Group Meeting 2019-05-01

All,

Attendance was low today but Matt and I went ahead with an issue and pull request review session regardless. I recorded minutes which are available in HTML format at https://www.w3.org/2019/05/01-audio-description-minutes.html

Please do look at the open issues and pull requests on the repository https://github.com/w3c/adpt and add any thoughts, comments, suggestions. After reviewing the two open issues without proposed changes, and seeing no reason not to proceed, I will open pull requests to address them, for further review.

In summary, I think we will target as small a specification as we can at first, which means no support for SMPTE timebase and only one description active at any one moment in time. This should make implementation easier. If strong use cases arise for adding features we can assess those and decide what to do – I would strongly encourage deferring adoption until later versions of the specification unless the specification is strongly broken otherwise.

Those minutes in text format:


   [1]W3C

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

                   Audio Description Community Group

01 May 2019

   [2]Agenda

      [2] https://lists.w3.org/Archives/Public/public-audio-description/2019Apr/0002.html

   See also: [3]IRC log

      [3] https://www.w3.org/2019/05/01-audio-description-irc

Attendees

   Present
          Nigel, Matt

   Regrets

   Chair
          Nigel

   Scribe
          nigel

Contents

     * [4]Topics
         1. [5]Review this agenda
         2. [6]Open pull requests
         3. [7]Issue 8 Constrain to one leaf element being active
            for audio at any one time?
         4. [8]Issue 10 Do we need to support `#contentProfiles`
            or `#processorProfiles`?
         5. [9]Future Meetings
         6. [10]AOB
         7. [11]Meeting close
     * [12]Summary of Action Items
     * [13]Summary of Resolutions
     __________________________________________________________

   <scribe> scribe: nigel

Review this agenda

   group: agenda looks fine

   Nigel: Attendance is low today but we'll use the time to make
   what progress we can

Open pull requests

   Nigel: Looking at #6 [14]https://github.com/w3c/adpt/pull/6
   ... Editorial fixes. Closes #4. Also makes any fragment ids
   valid.
   ... First to note is that Cyril raised the issue but hasn't
   managed to review the pull request yet.
   ... In the diff there are some changed dispositions - this is
   because I based the branch for this on the branch for pull
   ... request #9 so the disposition changes are included in
   those.

     [14] https://github.com/w3c/adpt/pull/6

   Matt: This looks fine to me. [approves pull request]

   Nigel: Thank you!
   ...
   ... The next one is pull request 7, Issue 0005 restructure #7
   [15]https://github.com/w3c/adpt/pull/7

     [15] https://github.com/w3c/adpt/pull/7

   Matt: Got that. Yes, this is a bigger change.
   ... This is a reordering of the sections rather than the
   content?

   Nigel: Yes, mainly.

   Matt: What was the driver for this change?

   Nigel: This was the feedback that we generated from the
   previous meeting where we tried to think about the best
   ... structure for the document especially for people coming to
   it for the first time.

   Matt: I remember
   ... You've added a real world example?

   Nigel: The new appendix D is renamed, the other examples were
   in other appendices, but I moved them into the Introduction.
   ... Section 2.1
   ... The diff has done something strange to the formatting of
   the example includes, the preview does a better job.

   Matt: Yes, that makes sense

   Nigel: One of the goals we had was to move the more important
   stuff higher up the document.

   Matt: That makes sense.

   Nigel: One effect is to move the requirements to the appendix

   Matt: This makes sense to me - I'm impressive we've kept it
   this small a document!
   ... [approves]

   Nigel: Thank you!
   ...
   ... Next is Permit only media timebase #9
   [16]https://github.com/w3c/adpt/pull/9

     [16] https://github.com/w3c/adpt/pull/9

   Matt: I said in the issue this fundamentally makes sense.
   ... It potentially makes it more of a distribution format than
   an archive format.
   ... Implementers may have a strong view.

   Nigel: I was hoping to elicit that view!

   Matt: My gut feeling, and talking with other broadcasters
   about, say, EBU-TT Part 2 as a way into EBU-TT, is that
   ... the ability to support the backwards compatibility remains
   very strong. Anything that forces a move away from that
   ... purity of form may present implementation challenges in the
   future.

   Nigel: I think I understand.

   Matt: If we try to chase something technically pure here then
   real world implementers may have problems if they
   ... cannot access the out of band data to recalculate any
   offsets.
   ... They may try to introduce their own fields or data to
   handle that within the file which may have unintended
   ... consequences or proliferation in varied practices.

   Nigel: That's true.

   Matt: If this is used for the share of data, and everything we
   have built so far is built on SMPTE timecode, I don't think
   ... we ever put any content in before the start of media. In
   all practical purposes it doesn't make a difference but it does
   ... require knowledge or an assumption about the start of media
   and how it relates.
   ... I don't know what role this group has in proffering
   suggestions for good practice operationally.
   ... We could give guidance about how to deal with this
   challenge, and if we don't then people might be creative
   ... and could come up with different solutions.

   Nigel: That's true. I think this group is perfectly placed to
   provide informative guidance of that sort.
   ... The other observation I would make is that we can start
   small and if there's a need to introduce SMPTE later we
   ... can do that. It's easier than to remove unneeded features.

   Matt: We just need to be sensitive to the trigger for that
   process.

   Nigel: Yes

   Matt: We would need to stay on top of when that may need to be
   revisited, rather than people coming up with creative
   workarounds.

   Nigel: Agreed.
   ... Given I've talked to 4 members so far who have been able to
   live without SMPTE, and nobody has objected, I feel
   ... we have enough consensus to proceed with the change.
   ... That takes us to the pull request itself.
   ... I removed everything to do with clock and smpte timebase
   and also noticed that region timing should be removed.
   ... It was already omitted, so there's no substantive change
   for that feature; the prohibition is just made explicit.

   Matt: Looks good to me, I will approve this. I will add a note
   too.

   Nigel: Great, thank you.
   ...
   ... There's one more: pull request 11 Change DFXP references to
   TTML2 profiles [17]https://github.com/w3c/adpt/pull/11

     [17] https://github.com/w3c/adpt/pull/11

   Matt: Just looks like a note in section 4

   Nigel: That's correct - the heritage is a bit of copy and paste
   from IMSC, which was based in TTML1, which didn't
   ... define as many standard profiles as TTML2 does. This work
   has to be based on TTML2 so I've changed it to match.

   Matt: Looks good to me. [approves]

   Nigel: Thank you, I'll merge those all later.
   ... Actually just to note I had a message from Peter Spoor
   saying he will take a look, and Chris O'Brien also said he
   would
   ... review the changes, so I'll give them a couple of days to
   add any more comments before merging them.

Issue 8 Constrain to one leaf element being active for audio at any
one time?

   [18]https://github.com/w3c/adpt/issues/8

     [18] https://github.com/w3c/adpt/issues/8

   Matt: The reasons for allowing this would need other changes in
   the specification.

   Nigel: For example?

   Matt: Say if this is used for spoken subtitles with multiple
   voices, then simply permitting multiple leaf nodes isn't
   enough.
   ... We should work through the use case and see what is needed.
   ... It is not a current requirement for this document.

   Nigel: Good point, we may add support for that later,
   potentially.
   ... Just to note as well that Pilar raised an issue on the
   w3c/tt-reqs repo asking for spoken subtitles support,
   ... and I think the requirement is all about signalling, rather
   than content, and I have an action to try to summarise that
   ... and get her views on that summary.
   ...
   ... Right now, the two commenters are in agreement for this
   issue.
   ... In the absence of any contrary views I will prepare a pull
   request to make the change.

Issue 10 Do we need to support `#contentProfiles` or
`#processorProfiles`?

   [19]https://github.com/w3c/adpt/issues/10

     [19] https://github.com/w3c/adpt/issues/10

   Nigel: Here I'm proposing we require support for the features
   in processors but not for them to be used in documents,
   ... where usage would be optional.
   ... It might be a useful output of this group to describe a
   best practice in how to use those features, at some point in
   the future.

   Matt: Agreed

   Nigel: We have agreement from the two commenters so far and no
   contrary views so I will prepare a pull request for this.

Future Meetings

   Matt: I could support a later slot in the day

   Nigel: That would probably be helpful for folk in Canada or the
   US, say.
   ... I feel that we have had low attendance and input so far,
   which may be a sign that everyone's happy, but I would
   ... be more confident if there were a higher volume of input.
   ... So I'll look to set up some calls, maybe just a couple, in
   May, at different times, to try to give more opportunity
   ... for participation.

   Matt: Makes sense.

   Nigel: Thank you, that's an action on me!

AOB

   Nigel: BBC put out a consultation about its iPlayer service
   recently, and RNIB contributed feedback,
   ... which is public at:

   [20]BBC Consultation

     [20] https://www.bbc.com/aboutthebbc/reports/consultation/iplayerpit

   [21]RNIB input (PDF)

     [21] http://downloads.bbc.co.uk/aboutthebbc/reports/consultation/iplayerpit/rnib.pdf

   scribe: I mention this because RNIB states support for a
   standard format for audio description, which this work is
   intended to create.

Meeting close

   Nigel: Thank you for that - only two of us on the call today
   but I think we made useful progress. [adjourns meeting]

Summary of Action Items

Summary of Resolutions

   [End of minutes]
     __________________________________________________________


    Minutes manually created (not a transcript), formatted by
    David Booth's [22]scribe.perl version 1.154 ([23]CVS log)
    $Date: 2019/05/01 13:43:29 $

     [22] http://dev.w3.org/cvsweb/~checkout~/2002/scribe/scribedoc.htm
     [23] http://dev.w3.org/cvsweb/2002/scribe/

Received on Wednesday, 1 May 2019 13:49:42 UTC