IRC log of tt on 2023-12-07

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Meeting: Timed Text Working Group Teleconference
16:02:29 [nigel]
Present: Andreas, Pierre, Nigel
16:02:31 [nigel]
Chair: Nigel
16:02:33 [nigel]
Regrets: Gary
16:02:52 [nigel]
Previous meeting: https://www.w3.org/2023/11/23-tt-minutes.html
16:02:57 [nigel]
Agenda: https://github.com/w3c/ttwg/issues/270
16:03:02 [nigel]
Present+ Atsushi
16:04:04 [nigel]
scribe: nigel
16:04:09 [nigel]
Topic: This meeting
16:05:17 [nigel]
Nigel: Today we have IMSC-HRM and DAPT on the agenda.
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.. Specifically with IMSC-HRM, some test suite changes and implementation work
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.. And for DAPT the main thing to cover is the languages PR
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.. Any other business, or points to make sure we cover within those agenda topics?
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no other business
16:06:26 [nigel]
Topic: IMSC-HRM
16:07:08 [nigel]
Subtopic: Add note on conversion from CTA 608 signals w3c/imsc-hrm#72
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github: https://github.com/w3c/imsc-hrm/pull/72
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16:07:56 [nigel]
Nigel: There's been some debate on the wording for this editorial note, would
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.. be good to complete it today if we can.
16:08:35 [nigel]
.. Pierre, any specific questions to be able to resolve this?
16:08:59 [nigel]
Pierre: The general disagreement is if we should make a more general statement and
16:09:06 [nigel]
.. I'm not excited by that for 2 reasons.
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.. 1 is, there's a case I'm comfortable talking about, which is the 608 line 21 example at 59.94fps
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.. I've seen a lot of streams like that.
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.. 2nd is, this is just a note and we should try to avoid designing a system in the note.
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.. The general question of conversion to IMSC is worth its own document.
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.. I'd like to keep it to just a specific example highlighting the challenges.
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.. That's my preference.
16:10:41 [nigel]
.. I'm happy with the group decision ultimately.
16:11:12 [nigel]
.. I can try to make another pass explaining that more clearly.
16:12:14 [nigel]
Nigel: Worth noting that this note is right after an "e.g." pointing to 608 in the text immediately above it.
16:13:21 [nigel]
.. Can we just remove the phrase about 59.94 Hz? The issue would remain at other frame rates
16:13:27 [nigel]
.. such as 29.97.
16:13:38 [nigel]
Pierre: If that resolves both your and Cyril's concerns I'm happy to do it.
16:13:43 [nigel]
Present+ Cyril
16:14:21 [nigel]
Cyril: I don't think adding the sample rate helps, and I don't want to add a note that is not totally accurate.
16:15:53 [nigel]
Nigel: Maybe say "at the video field rate" to clarify that this isn't happening once every few seconds,
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.. but many many times per second.
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Pierre: There's a general misunderstanding - 608 is sampled at a field rate, but sometimes the packets
16:16:44 [nigel]
.. are combined for other transport mechanisms. But 608 has no option other than sampling at the field rate,
16:16:50 [nigel]
.. at least classic 608, like line 21.
16:17:09 [nigel]
Nigel: Is this the change that we can accept then?
16:17:19 [nigel]
Pierre: I'll put this on screen. [shares screen]
16:18:47 [nigel]
.. Now says "... for every CEA-608 packet, which are sampled at the video field rate. ..."
16:19:41 [nigel]
Cyril: I like that we removed the 59.94. Field rate is related to interlace. Should we say field or frame?
16:19:51 [nigel]
.. I'm fine with this. A field is a frame when there's no interlace.
16:20:03 [nigel]
.. And maybe we will have to change it again if we have Teletext issues.
16:21:16 [nigel]
Nigel: Teletext doesn't have this "build up a buffer character by character" approach, so it doesn't arise.
16:21:27 [nigel]
Pierre: That's modified, I'll ask for a re-review.
16:21:36 [nigel]
SUMMARY: Live edits made, needs re-review
16:21:58 [nigel]
Subtopic: IMSC-HRM Tests and call for implementations
16:22:22 [nigel]
Nigel: Exciting news: I completed a second validation implementation of IMSC HRM,
16:22:36 [nigel]
.. based on the EBU-TT Live Interoperability Toolkit, as a starting model.
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.. That means it can process all the files in the test suite that can conform to EBU-TT-D as well as IMSC Text.
16:23:22 [nigel]
.. As part of this exercise I updated, and Pierre reviewed, the tests to be EBU-TT-D conformant.
16:23:38 [nigel]
.. We had some other fun along the way, identifying some tests that weren't quite right,
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.. and found bugs.
16:24:13 [nigel]
Pierre: The bugs we found were in the implementations and we are fixing them right now.
16:25:24 [nigel]
Nigel: We also in the process of adding tests for region presentation.
16:25:38 [nigel]
.. That came out of a fun discussion about the handling of tts:showBackground on region elements
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.. that set a backgroundColor that is not entirely transparent.
16:26:28 [nigel]
.. There's also an issue about one of the test pairs, dur005, which we're in the process of resolving.
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.. So it's been a useful exercise.
16:27:18 [nigel]
.. Next steps: finish sorting out the tests, and update the implementation report to add the additional implementation.
16:27:38 [nigel]
Pierre: Have you checked the implementation report?
16:28:35 [nigel]
Nigel: Not yet.
16:28:41 [nigel]
Atsushi: I have not either.
16:29:25 [nigel]
.. The main question is we may need to list the mapping between HRM features and the test suite.
16:29:33 [nigel]
Pierre: In each of the test files there is a description.
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Atsushi: In any case we may need a script to list those things easily.
16:29:50 [nigel]
Pierre: Why?
16:30:08 [nigel]
Atsushi: There are a bunch of test files.
16:30:26 [nigel]
Pierre: They're organised into two directories, which are sufficient for automatic testing.
16:30:35 [nigel]
Atsushi: In any case I need to set some time aside to check it.
16:30:37 [nigel]
Pierre: Ok.
16:32:17 [nigel]
Nigel: Edits needed at the moment are: adding the new tests, and the 2nd validating implementation
16:32:26 [nigel]
-> https://www.w3.org/wiki/TimedText/IMSC-HRM-1ED-Implementation-Report Implementation Report
16:32:48 [nigel]
Nigel: If at some stage we need to demonstrate the truth of the emails to the Chair listed under
16:32:56 [nigel]
.. Content producing implementations, I'm sure we can find a way to do that.
16:33:16 [nigel]
.. Anything else on IMSC-HRM?
16:33:28 [nigel]
Pierre: Not for me, thanks for everyone's help and input on this. We're getting super close
16:33:39 [nigel]
.. and hopefully can close this very early next year if not this year.
16:33:52 [nigel]
Topic: DAPT
16:34:48 [nigel]
Subtopic: Rework audio description original and translation languages w3c/dapt#179
16:34:54 [nigel]
github: https://github.com/w3c/dapt/pull/179
16:35:16 [nigel]
Nigel: This has been open since July 31 and has been through an amazing number of iterations,
16:35:21 [nigel]
.. each one making it better than before.
16:35:34 [nigel]
.. I think we're probably about done with it, and would like to know if we can merge it today
16:35:40 [nigel]
.. or if anyone wants more review time.
16:35:59 [nigel]
.. Since the last review the main change is to model the daptm:langSrc attribute better and to
16:36:06 [nigel]
.. define the semantics and constraints better.
16:36:21 [nigel]
.. Those changes are in line with the issue and pull request discussion, I think,
16:36:32 [nigel]
.. but I am aware that Andreas had some reservations.
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.. I did try to address those.
16:37:11 [atai]
q+
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ack at
16:37:30 [nigel]
Andreas: Thanks first for all your work on that pull request. It was an amazing amount of editing
16:37:42 [nigel]
.. work to resolve the different comments. I think it gets better and better.
16:37:57 [nigel]
.. As I signalled, maybe offline, I'm happy with the way forward as described in the comments.
16:38:17 [nigel]
.. It's not just one line, you have to check the whole document.
16:38:43 [nigel]
.. I can review it in the next couple of weeks but if you want to merge it now that's okay.
16:39:16 [nigel]
Nigel: I could merge it and then if you find issues with it then open new issues.
16:39:19 [nigel]
Andreas: That would be okay.
16:39:37 [nigel]
Cyril: I concur with Andreas. I would also like to give it another review, and I can do it tomorrow.
16:40:02 [nigel]
Nigel: OK then I will leave it open and then react based on the result of your review.
16:40:20 [nigel]
Cyril: After my review I will try to implement the solution in my prototype tool to see if there is any
16:40:34 [nigel]
.. problem in our source content. I can do the review first. If I see any problem I will open a new issue.
16:40:39 [nigel]
Nigel: Great, thank you.
16:41:26 [nigel]
SUMMARY: @cconcolato to review, @nigelmegitt to respond accordingly. @andreastai to read through when time allows.
16:41:56 [nigel]
Subtopic: Next steps and Wide Reviews
16:42:04 [nigel]
Cyril: Do we have all the responses?
16:42:07 [nigel]
Nigel: Not quite.
16:42:13 [nigel]
Cyril: We have TAG and i18n.
16:42:48 [nigel]
Nigel: We haven't had the formal response from APA yet.
16:43:03 [nigel]
.. We've been told not to expect a response on Security unless they identified a problem.
16:43:15 [nigel]
Atsushi: If we can resolve all of the issues raised against DAPT then we can state that
16:43:19 [nigel]
.. all HR is finished.
16:43:36 [nigel]
Nigel: Please could you check on the status of those, Atsushi?
16:43:45 [nigel]
Atsushi: Of course, I will do it during winter holiday season.
16:44:39 [nigel]
Nigel: My other question is about the feedback from DVW - do we have a way to complete
16:44:48 [nigel]
.. the conversation with them after the detailed discussion responses?
16:45:03 [nigel]
Cyril: I'm hoping to get a response from them, yes.
16:46:36 [nigel]
Nigel: In terms of tasks, we have some issues that need decisions to be made,
16:46:48 [nigel]
.. at some point we need test suites (not formally until after CR),
16:47:02 [nigel]
.. and there are a couple of PRs open from June that need something doing with them.
16:47:10 [nigel]
Cyril: Those PRs are still on my list!
16:47:41 [nigel]
Topic: Meeting close
16:47:49 [nigel]
Nigel: We have one more meeting this year, on 21st December.
16:48:19 [nigel]
.. We've completed our agenda today. Thank you everyone. [adjourns meeting]
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rrsagent, make minutes
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I have made the request to generate https://www.w3.org/2023/12/07-tt-minutes.html nigel
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s/We also in the process of adding tests/We are also in the process of adding tests
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rrsagent, make minutes
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I have made the request to generate https://www.w3.org/2023/12/07-tt-minutes.html nigel
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scribeOptions: -final -noEmbedDiagnostics
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zakim, end meeting
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As of this point the attendees have been Andreas, Pierre, Nigel, Atsushi, Cyril
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RRSAgent, please draft minutes v2
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I have made the request to generate https://www.w3.org/2023/12/07-tt-minutes.html Zakim
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I am happy to have been of service, nigel; please remember to excuse RRSAgent. Goodbye
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Zakim has left #tt
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rrsagent, excuse us
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I see no action items