14:59:09 RRSAgent has joined #tt 14:59:09 logging to https://www.w3.org/2019/03/21-tt-irc 14:59:11 RRSAgent, make logs public 14:59:11 Zakim has joined #tt 14:59:13 Meeting: Timed Text Working Group Teleconference 14:59:13 Date: 21 March 2019 14:59:36 Agenda: https://github.com/w3c/ttwg/issues/27 14:59:51 scribe: cyril 14:59:56 chair: nigel 15:00:15 glenn has joined #tt 15:01:23 Present: Cyril, Nigel, Gary 15:01:34 Log: https://www.w3.org/2019/03/21-tt-irc 15:02:21 plh has joined #tt 15:02:51 Present+ Glenn, Andreas 15:04:07 Present+ Pierre 15:04:17 Present+ Philippe 15:04:26 Topic: this meeting 15:04:39 nigel: there is a lot to get through 15:04:43 ... good to have 2 hours 15:04:46 ... lots to discuss 15:04:54 ... main topics will be charter 15:04:58 ... TTML3 modules 15:05:07 ... to make sure we have a consistent language 15:05:18 ... some time for WebVTT 15:05:36 ... actions to MPEG and VR-IF 15:05:50 ... actions also to propose options for the Sept F2F meeting 15:06:42 ... there are some PR for TTML3 15:06:52 ... any AOB? 15:07:08 glenn: some PRs on Profile Registry 15:07:29 Topic: TTWG Charter 15:07:55 nigel: we have 4 PR to review 15:08:17 -> https://github.com/w3c/charter-timed-text/pulls Timed Text Charter Pull Requests 15:08:57 atai2 has joined #tt 15:09:05 atai2 has left #tt 15:09:11 nigel: the issue was to make sure the new requirements that we agreed, labelled requiring charter revisions, are supported in the charter 15:09:26 ... there was live contribution 15:09:33 ... from EBU 15:09:57 ... current charter already says to consider things from EBU and other similar groups 15:10:20 ... given that, we came to an agreement that we don't need a significant charter change 15:10:22 atai2 has joined #tt 15:10:28 ... so the PR does not need much change 15:10:40 ... there is only one line in the scope section under TTML3 15:10:48 q+ 15:10:57 ... the main part that needs to change is about supporting Audio Description 15:11:08 ... there is a scope and deliverable section that points to the CG report 15:11:21 ... the scope is publish a recommendation 15:12:07 ... a profile of TTML for Audio Description 15:12:54 atai2: on the first point, live streaming, we want to work on live contribution which is a bit different from streaming 15:13:17 ... it should not be an alternative to HLS streaming 15:13:37 nigel: agree, I'll add a comment to the PR 15:15:12 ack a 15:15:25 nigel: back on Audio Description deliverable 15:16:06 cyril: could the profile be of TTML3? 15:16:24 nigel: It could be but all the features seem there in TTML2 15:16:42 pal: we have to be careful 15:17:02 ... we should reserve TTML3 for significant features that would impact conformance in a significant way 15:17:14 ... because the timeline for TTML3 is not the same 15:17:33 glenn: I agree the profile should be a TTML2, if it does not use TTML3 features 15:17:41 pal: can the charter be silent? 15:17:49 ... I'm concerned with the charter be restrictive 15:17:59 glenn: I agree, the less we say the better 15:18:05 nigel: this can be changed 15:18:32 ... I'll omit TTML version number 15:19:55 ... expected completion are intent but can be moved 15:20:32 ... the other update is in coordination, adding ADCG 15:20:55 ... any other comment? 15:21:26 nigel: next one is "Increase scope to include maintenance of all Recommendations" 15:22:06 nigel: the change is simple, be less specific 15:22:28 ... about the versions of the spec to maintain 15:22:30 ... comments? 15:22:50 nigel: next one is "Update text re meeting schedule" 15:23:45 ... the meeting schedule currently requires to meet at TPAC but we don't necessarily want that 15:24:05 ... the new text says meeting at least once a year, usually at TPAC 15:24:34 ... next "Add wording permitting TTML3 and a modular approach." 15:25:26 ... there has been discussions in different places about the language we use here 15:25:56 ... it seems that we've converged on the idea that TTML3 is a thing whose collective name is not really agreed, and each document is a specification 15:26:04 ... some other specifications will be defining modules 15:26:25 q? 15:26:33 ... the changes proposed by glenn in TTML3 is a module registry 15:26:39 pal has joined #tt 15:26:43 q+ 15:27:02 ... we need to know if the module registry is a deliverable 15:27:27 glenn: it would be the same as the profile registry, i.e. a WG note 15:27:45 ... the registry is not the thing that pulls them together 15:28:08 ... the registry will list the existing internal modules 15:28:23 ... and serve as a list of external module 15:28:41 ack pal 15:28:52 pal: we are creating so much burocracy 15:29:09 ... what problem are we trying to solve by having that in the charter 15:29:17 ... I love the idea of modularization 15:29:42 glenn: I agree we should say the minimum in the charter 15:30:10 pal: for example modules could be done for a 2nd edition of TTML2 15:30:24 nigel: I'm happy to make this vaguer 15:30:59 glenn: it's good to inform AC members about the intent of the group but we don't want to have every line item cited here 15:31:03 ... we need to find a balance 15:31:16 nigel: what is the minimum we need to say? 15:31:23 plh: I'm thinking ... 15:31:42 ... I don't think there is a minimum 15:31:48 pal: what does CSS do? 15:31:57 nigel: it says they will publish modules 15:32:09 ... it says CSS is a specification consisting of modules 15:32:20 ... the snapshot says it gathers specifications 15:32:34 pal: can we say the product of the group is a core specification, profiles and modules 15:32:43 cyril: agree 15:32:46 nigel: possibly 15:33:02 plh: at the end of the day, the scope section defines the range of IP affected 15:33:11 ... what this group is working on 15:33:19 ... if it ends in one spec or ten specs 15:33:46 ... it does not matter, unless some AC have strong feelings but they should be in this group 15:33:54 nigel: ok, so let's try to go minimal 15:34:24 ... do we even need to say we will publish TTML3? 15:34:41 plh: not necessarily, not in the scope 15:35:16 ... in the deliverable, we'll have a list of the existing publications 15:35:28 ... for TTML3 we can provide vague wordings 15:35:43 ... like "the next version of the spec made of one or mode documents" 15:35:48 nigel: what about notes? 15:35:55 plh: not necessarily 15:36:03 ... but registry can be listed 15:37:09 nigel: we'll say in the scope "publish recommendations for new TTML specifications as needed" 15:37:50 .. in the deliverables, at the moment there is a TTML3 15:38:33 ... I need to add that it may consist of one or more documents 15:39:09 cyril: we could leave '3' out 15:39:43 nigel: how important is the "update working draft" section 15:39:59 plh: that's important because if you join the group, you commit to it 15:40:45 ... for those that don't exist, you're commited only after publication 15:41:05 ... and that list will be generated by W3C 15:41:09 ... we are tracking that 15:41:28 ... despite your attempts to have multiple repos here and there 15:41:56 q+ 15:42:18 nigel: there is a wording change non controversial in success criteria 15:42:40 ... because we might publish notes that could be interpreted as specifications 15:42:53 ... and I don't want them to be interpreted regarding that section 15:44:10 plh: one set of thoughts related to the naming, whether TTML 3 or TTML Snapshot 15:44:15 ... you can call it whatever you want 15:44:20 ... it's more of a marketing question 15:44:50 ... from the process it doesn't matter 15:45:20 ... but it's not simple to make noise about it 15:45:35 ... we won't present each module in the press 15:46:05 nigel: that's a consideration of the modular approach 15:46:19 plh: it might make it harder to communicate about what TTML is 15:46:31 nigel: I think we have a bit of answer already 15:46:45 ... make the noise about profiles 15:46:56 ... like for Audio Description 15:47:36 acl plh 15:48:14 ack plh 15:48:15 Cyril: Re the success criteria, it's all about specifications, you could make it a bullet point list 15:48:25 s/acl plh// 15:49:17 plh: btw, CSS Snapshots are not recommendations, just WG notes 15:49:27 glenn: I generally oppose publishing snapshots documents 15:49:54 nigel: I think one of the problems of getting different specs to recommendations is getting the impetus for tests 15:50:34 ... if we do what we said, provide tests with spec, we should not be stuck in CR 15:51:12 plh: regarding success criteria, would there be value in taking consumers of TTML more into account 15:51:44 ... for example for the VR module, do we want to make sure we have at least one consumer that is able to understand the VR module 15:52:17 nigel: in the past, we required at least one presentation processor 15:52:31 ... I think that point can be addressed when we think of CR exit criteria 15:52:48 plh: ok, it can be pushed to exit criteria for each module 15:53:00 Topic: TTML Profile Registry Actions, Pull Requests and Issues 15:54:10 s/Topic: TTML Profile Registry Actions, Pull Requests and Issues// 15:54:59 nigel: iterating through the other 3 issues: fix the timeline (to me), assign chairs (to plh), and WebVTT (assigned to nobody) 15:55:11 ... my proposal is to leave these issues as is for the moment 15:55:17 plh: sounds good to me 15:55:39 Topic: TTML Profile Registry Actions, Pull Requests and Issues 16:01:36 pal: given that Mike Dolan is not here, I recommend skipping to TTML2 and TTML3 16:01:51 ... we need the right people on the call 16:02:07 glenn: I'd like to discuss PR 69 16:02:33 nigel: let's discuss PR 69 then 16:02:50 Topic: Clarify codecs parameter syntax requirements (#63). tt-profile-registry#69 16:02:52 github: https://github.com/w3c/tt-profile-registry/pull/69 16:03:39 cyril: I miss some context on why we don't want to change the IANA registry 16:03:57 glenn: my recollection is that we do not need to update the body of the media type 16:04:34 ... we did make one change to remove one misleading sentence which should not trigger IANA review 16:05:06 cyril: what is wrong with triggering IANA review 16:11:07 Cyril: The note should be in section 2 not section 3. 16:11:40 .. The syntax of the codecs is being defined in section 3. 16:11:47 Glenn: Those are requirements on registration 16:12:03 Cyril: The requirements are as they are to meet the requirements of the codecs parameter. 16:12:23 .. My problem is we don't formally define the codecs syntax. 16:12:48 Glenn: Yes we do, under Section 2, codecs. 16:13:07 Cyril: It's defined by example only. 16:14:16 Nigel: If you're worried about the syntax of the operators and where it is defined, Cyril, that's pull request #70. 16:14:41 Glenn: Looking at the note here, is there any argument about the correctness of the statement? 16:15:01 Cyril: I'm arguing about the location, it describes an effect not listed formally anywhere else. 16:17:29 .. I can raise an issue for defining codecs in section 2 16:17:34 Nigel: I think that would be the right approach. 16:18:38 Cyril: I will raise the issue. 16:19:23 Glenn: Please could you remove your "request changes" review on #69? 16:19:41 Cyril: Let me think about it. 16:20:50 Topic: WebVTT Implementation report 16:21:02 Gary: This is waiting for comments on the pull request for the snapshot. 16:21:40 Topicc: mark at-risk features in a new snapshot webvtt#449 16:21:45 s/icc/cc 16:21:50 s/cc/ic 16:21:54 scribe: cyril 16:23:08 plh: I sent the email last week, we have some comments in the PR that have been addressed 16:23:31 ... if people have issues with republishing the document as proposed by Gary in two weeks 16:23:41 ... people should speak up, one more week to do so 16:24:03 -> https://lists.w3.org/Archives/Public/public-tt/2019Mar/0023.html Philippe's CfC email of 14th March 16:24:06 nigel: is that a call for consensus 16:24:07 plh: yes 16:24:28 nigel: any update on the implementation report 16:24:42 gkatsev: I added a new tab as result of API parsing 16:24:52 ... some are failing because the tests are out of date 16:25:04 ... I need to update the tests 16:25:12 q+ 16:25:37 plh: i'm assuming that if there was any red flag we would have marked it at risk 16:25:44 ... how long should we stay in CR? 16:25:49 ... the minimum is 28 days 16:26:18 gkatsev: we should go with the minimum 16:27:01 scribe: nigel 16:27:01 ack plh 16:27:16 Cyril: There was a question about support for what Netflix regards as essential Japanese features. 16:27:25 .. The response was not clear to me, about if it is supported and to what extent. 16:27:48 Gary: I'm not sure exactly the specifics. A lot of support in WebVTT comes from the rendering engine like HTML, so 16:28:05 .. Ruby is supported and a lot of the rtl and other features are only available if the vendor supports them. 16:28:25 Glenn: So to do Ruby you have to do the CSS styling for Ruby technique and then associate a stylesheet with the WebVTT document? 16:28:35 Gary: You can use the ruby and rt tags. 16:28:39 Glenn: Directly in the text in WebVTT? 16:28:48 Gary: Yes. As for other Japanese features I am unsure. 16:28:53 Cyril: What about vertical text? 16:29:00 Gary: I believe that is supported via CSS. 16:29:14 Cyril: I thought there was a line level setting to set the line layout to vertical? 16:29:19 Gary: Yes there is a vertical setting. 16:29:32 Cyril: Do you have a pointer to the tests that demonstrate rendering interop for this feature? 16:29:57 Gary: There is a test for ruby support, I'm not sure about vertical 16:30:59 Nigel: [can't find it] 16:31:04 Gary: [can't find it either] 16:31:19 Cyril: If you could offline send pointers to the tests for ruby, vertical text? 16:31:32 .. For ta te chu yoko and bouten you're saying it's CSS only? 16:31:42 Gary: I think that is currently the case, yes. 16:31:58 Cyril: Okay, and we don't have tests for that, right? The test suite for WebVTT doesn't mandate CSS and there's no 16:32:03 .. section of the tests that includes CSS? 16:32:11 Gary: We do have tests for styling support, yes. 16:32:20 Cyril: And those tests don't test the Japanese features, right? 16:32:22 Gary: Yes 16:32:29 Cyril: Ok, maybe we could add them? 16:32:33 Gary: I could take a look at that. 16:32:48 Pierre: What happens if a CR is republished and the test suite is not sufficient. Another CR? 16:33:02 Philippe: No, it requires that the test suite is completed. 16:33:12 Nigel: We've done this before, worked on the test suite during CR. 16:33:29 Pierre: The danger is that if during the test suite development new at risk features are needed then that's a setback. 16:33:34 Philippe: Yes you have to republish. 16:33:44 .. One thing is that we don't want to test CSS and rendering, just WebVTT. 16:33:59 Cyril: I only want to know if Japanese support is present, so it seems reasonable to have tests. 16:34:19 Philippe: If WebVTT doesn't have anything specific for Japanese then we should not test HTML. 16:34:22 q+ 16:34:29 .. It's not the job of WebVTT to test everything in HTML. 16:34:35 .. You would be asking if HTML supports Japanese. 16:34:53 Glenn: The answer is WebVTT has no support for Japanese but allows for pass-through syntax of Ruby and CSS styles 16:35:05 .. that puts all the burden on the presentation engine to use HTML and CSS to do Japanese formatting. 16:35:09 ack atai2 16:35:31 Andreas: I need to get my head clear on this, so apologies - WebVTT lists certain CSS features, not all of them, that it 16:35:50 .. supports through the pseudo cue setting. Where WebVTT says it supports it, even by delegation to CSS, it is needed 16:36:08 .. to test that it is rendered correctly by sufficient applications. They are critical features for rendering subtitles. 16:36:24 .. Either they are supported or not, otherwise you would say that WebVTT would not support colour, say, so of course 16:36:36 .. it should be tested with WebVTT that the CSS based rendering actually comes out correctly. 16:37:31 Nigel: The purpose of the tests is to demonstrate implementability - I think you're pointing Andreas at the idea that 16:37:47 .. we want to ensure there is no accident that the CSS styling actually cannot be implemented. 16:38:18 Cyril: I agree that the purpose of the tests for the CR process is to demonstrate implementability interoperably and 16:38:40 .. maybe the CG has the job to demonstrate that WebVTT can solve classes of problem in presentation especially on the 16:38:42 .. internet. 16:38:54 Philippe: Are you looking for pass-through tests with ruby markup in it? 16:39:13 Cyril: David Ronca's email lists 5 things for which we have no evidence from the WebVTT tests that it can do them. 16:39:23 .. 1. Vertical text - a core feature with no tests. 16:39:33 .. 2. Ruby - also a feature of WebVTT. 16:40:22 .. 3. Bouten, 4. Ta te chu yoko, 5. Slanted text - possibly not core features of WebVTT and reliant on CSS, so maybe 16:40:35 .. for those the CG could demonstrate (not for CR) that the features can be supported. 16:40:49 Pierre: The spec does define conformance directly related to CSS, it's not entirely a pass-through. 16:40:57 .. It's not entirely true that it is a pass-through. 16:41:14 Glenn: It does not detail specific CSS style formatting, and all the features you're talking about here are specific properties, 16:41:33 .. bouten is text-emphasis, ta te chu yoko is text-combine, and vertical is writing-mode. 16:41:52 .. Potentially also ruby-align and ruby-position properties also. There are at least 5 properties. 16:41:54 Nigel: Slanted text? 16:42:04 Glenn: I don't think CSS has anything to support that directly right now. 16:42:09 Pierre: Correct, there's no shear. 16:42:32 Nigel: There's a kind of shear isn't there, but not the right kind, i.e. it's on the wrong kind of element. 16:42:47 Pierre: It is definitely not what is needed, ideally. It doesn't match the expectation of authors. 16:42:56 Philippe: That sounds like a CSS issue not a WebVTT issue. 16:43:25 Nigel: Every CSS property that is needed must be on the whitelist in WebVTT because everything else is ignored. 16:43:46 Philippe: Correct. Are you saying some needed CSS properties are not on the whitelist? 16:43:50 Pierre: Pointer to the whitelist? 16:43:54 Gary: ยง8.2.1 16:44:00 Pierre: I see. 16:44:07 Gary: So text-combine: upright; is allowed. 16:44:12 Pierre: Thanks for pointing it out. 16:44:44 Nigel: Sounds like something to follow up offline. 16:44:56 Glenn: And verify all those properties I mentioned are on the whitelist. 16:45:15 Pierre: Some of the properties that are needed are in draft but not on the whitelist because they aren't ready today, 16:45:20 .. like fill-line-gap. 16:45:33 https://www.w3.org/TR/webvtt1/#the-cue-pseudo-element 16:45:39 Glenn: I just mean the ones I listed. 16:45:51 Pierre: text-emphasis is in CSS but not on the whitelist. 16:45:59 Glenn: ruby-align is not there. 16:46:12 Pierre: No because it's part of the ruby one... maybe not. 16:46:51 scribe: cyril 16:46:56 Topic: TTML3 Pull Requests 16:47:32 nigel: we have one issue "add module framework" 16:47:47 github: https://github.com/w3c/ttml3/pull/30 16:49:08 nigel: cyril asked for some text to be removed 16:49:15 ... I believe it has been removed 16:49:41 cyril: let's go ahead, I'll review and raise an issue if needed 16:49:50 nigel: I asked for a change on the name module 16:50:48 ... the request is to define a module as elements, attributes or specs for that 16:50:58 glenn: that's how I view a module 16:51:12 q+ 16:51:37 ack atai 16:52:20 cyril: what about the term Module in TTML2 16:52:36 glenn: those are defined and go back to TTML1 16:54:17 ack cy 16:58:50 topic: sept F2F meetings 16:59:44 nigel: we have 3 proposals 17:00:01 https://github.com/w3c/ttwg/issues/30 17:01:59 q+ 17:02:03 q+ 17:03:56 ack pal 17:03:57 ack at 17:05:07 nigel: people should add other options if they want to 17:06:31 atai2 has left #tt 17:06:42 RRSAgent, draft minutes 17:06:42 I have made the request to generate https://www.w3.org/2019/03/21-tt-minutes.html cyril 17:07:27 i/Cyril: The note should be in section 2 not section 3./scribe: nigel 17:07:37 Regrets: Thierry 17:07:41 rrsagent, make minutes 17:07:41 I have made the request to generate https://www.w3.org/2019/03/21-tt-minutes.html nigel 17:08:53 scribe: nigel 17:09:09 Topic: Liaisons to MPEG and VR-IF 17:09:26 Nigel: Liaisons have been sent, need to follow up on one of the VR-IF recipients because the email address didn't work. 17:09:31 Topic: AD CG 17:10:03 Nigel: I've initiated a sequence of 4 meetings of the AD CG on Tuesdays at 1100 UTC (based on a poll to find a meeting time) 17:10:22 .. and the first one was two days ago. Please feel free to join, and I can change the time if that's helpful. 17:10:33 .. The goal is to tidy the document to be ready for this group to begin taking it on. 17:10:37 Topic: Meeting close. 17:10:52 Nigel: Thanks everyone, sorry for running 6 minutes over. [adjourns meeting] 17:10:57 rrsagent, make minutes 17:10:57 I have made the request to generate https://www.w3.org/2019/03/21-tt-minutes.html nigel 17:26:07 scribeOptions: -final -noEmbedDiagnostics 17:26:09 rrsagent, make minutes 17:26:09 I have made the request to generate https://www.w3.org/2019/03/21-tt-minutes.html nigel