14:02:15 RRSAgent has joined #tt 14:02:15 logging to http://www.w3.org/2016/09/01-tt-irc 14:02:17 RRSAgent, make logs public 14:02:17 Zakim has joined #tt 14:02:19 Zakim, this will be TTML 14:02:19 ok, trackbot 14:02:20 Meeting: Timed Text Working Group Teleconference 14:02:20 Date: 01 September 2016 14:03:04 glenn has joined #tt 14:03:51 Present: dakim, glenn, mike, nigel, pal 14:03:54 Chair: Nigel 14:04:00 scribe: nigel 14:04:07 Regrets: tmichel 14:04:39 Topic: This meeting 14:05:23 nigel: Several topics have been discussed recently: TPAC, IMSC Image profile, TTML2 inline region semantics 14:06:32 nigel: Any other business or points to prioritise? 14:06:37 pal: Inline region semantics 14:07:15 Topic: TPAC 2016 14:07:29 nigel: You have 1 day left to register if you have not already, and get the advanced rates 14:07:59 action-475? 14:08:00 action-475 -- Nigel Megitt to Contact the chair of the web & tv ig to ask about schedule and joint meeting time. -- due 2016-07-28 -- OPEN 14:08:00 http://www.w3.org/AudioVideo/TT/tracker/actions/475 14:08:32 nigel: Still no response from Web & TV IG, I have no idea why. Will keep pestering them. 14:08:55 action-476? 14:08:55 action-476 -- Nigel Megitt to Put together a tpac straw man agenda -- due 2016-08-25 -- PENDINGREVIEW 14:08:55 http://www.w3.org/AudioVideo/TT/tracker/actions/476 14:09:10 https://www.w3.org/wiki/TimedText/tpac2016#TTWG_TPAC_2016 14:12:33 nigel: [runs through draft agenda as it stands] 14:12:55 glenn: I'm going to post a couple of new issues that we will probably need to discuss. 14:13:15 ... One is support for rounded background, and there are a couple of issues regarding 14:13:30 ... more complete support for the more advanced background attributes. There may be a 14:13:45 ... few missing that I think should be added. I'll post some issues on these to drive agenda items. 14:14:05 ... Also on the support for anonymous region generation I've got some material on that as well. 14:14:10 Present+ Andreas 14:14:23 glenn: It turns out that we need to add back something we used to have in animation, which 14:14:35 ... is the ability to have animation elements point at content elements, but we changed it 14:14:46 ... around to have content elements point at animation elements. To support anonymous 14:15:00 ... inline region for the current region we need an anonymously generated set element point 14:15:04 ... back up to the region. 14:15:11 atai has joined #tt 14:15:39 rrsagent, generate minutes 14:15:39 I have made the request to generate http://www.w3.org/2016/09/01-tt-minutes.html nigel 14:17:06 atai: I can show something on HTMLCue/VTTCue and we should spend time looking at it. 14:17:17 ... There's a question regardless of approach if we should talk with another WG about this. 14:17:28 ... I think something will need to change in the HTML spec because the spec is format 14:17:40 ... independent but the implementation is WebVTT specific, so to have a format agnostic 14:17:53 ... spec for cues then some additions or changes to HTML are needed. 14:18:45 nigel: Do you know which other groups? 14:19:01 atai: I think we need to know which group is responsible for that part of the spec. 14:21:18 glenn: We could actually draft a spec or some material in this group, publish it as a Note and 14:21:32 ... throw it over the fence to another group to turn it into a Rec. That's one option. 14:22:14 atai: What I found out is firstly that the TextTrackCue should be implemented correctly in 14:22:29 ... the browser. They only have VTTCue specific implementations, though as I read it from the 14:22:44 ... HTML spec there should be a generic TextTrackCue implementation. Initially it may be as 14:22:56 ... simple as following the spec as it is written and then add a property as a payload. Then 14:23:11 ... the rest would be done with javascript as a small addition that would help present any other 14:23:13 ... timed content. 14:24:42 nigel: Any other requests for agenda items, or for scheduling? 14:26:12 atai: I think there could be some interest in Web & TV IG in better integration between TTML and HTML5. 14:26:25 nigel: Okay, I'll keep chasing on the joint meeting action. 14:28:03 close action-476 14:28:03 Closed action-476. 14:29:14 Topic: TTML1 & TTML2 issues, actions, PRs, editorial actions etc 14:29:33 nigel: I think we wanted to discuss inline anonymous regions... 14:29:49 glenn: I propose that we adopt a parameter on a per document basis that defines the desired 14:30:04 ... behaviour for anonymous inline regions. We have already done half the work, for new 14:30:17 ... regions, and need to make progress with current. Then later if we want to choose only 14:30:28 ... one of those options we can do that. That's my proposal. 14:39:31 glenn: Perhaps we should try to discuss how we develop and possibly discard features during the spec development process, at TPAC. 14:39:53 glenn: My general position is that the process step of dropping features without implementation applies. 14:40:01 nigel: That's certainly the formal position. 14:40:17 pal: I'm not sure if I'm the only one wanting to discuss this. 14:40:20 atai: I'm also interested in this. 14:40:29 pal: This is about how we allocate our limited amount of resources. 14:41:53 +q 14:42:56 nigel: I will add an agenda topic for TPAC to consider our deliverable timelines and how 14:43:18 ... reliable our estimates are for meeting them, and if we need to take any action. 14:43:33 glenn: I have scheduled a lot of time to get a CR candidate ready for Nov 1. 14:43:35 ack 14:43:45 q- atai 14:44:13 atai: I think we should discuss the balance between adding new features and the challenge 14:44:28 ... of implementation when the spec is bigger, from a market perspective. It is important for 14:44:43 ... us to have our specs implemented correctly. We should discuss our current experiences 14:44:52 ... and if this means anything for our spec efforts in general. 14:44:57 s/ack// 14:45:48 nigel: Summarising, I'll add an agenda topic for TPAC, and on the subject of anonymous 14:46:00 ... regions, Glenn will go ahead with speccing the anonymous set approach as he proposed. 14:46:22 glenn: Just to note that I finally merged those PRs. 14:46:36 ... One point: when you do propose a PR please don't expand the RCS keywords otherwise 14:46:41 ... I have to manually remove them. 14:47:47 nigel: It could be that there's a problem with the check-in hook then. 14:48:03 glenn: It did not unexpand them when you checked it in. No problem though, I fixed it. 14:49:05 glenn: Regarding the other PR that I merged I'll post another issue for clearing up the defined term 14:49:09 ... references. 14:49:22 nigel: Thanks, that was for my suggestion prior to merging the PR, that's fine. 14:49:43 glenn: I'm going to try to post a number of new PRs between now and Lisbon so there may 14:49:54 ... be some things for people to start reviewing. 14:49:58 nigel: That would be helpful, thank you. 14:51:17 Topic: IMSC 14:51:27 nigel: The main topic discussed recently is embedded images. 14:51:52 pal: It would be good to have a way to generate the ISOBMFF files with embedded images, 14:51:57 ... which gpac doesn't do today. 14:52:06 glenn: You mean embedded in the BMF not the TTML, right? 14:52:17 pal: Correct. The fact that gpac doesn't support it is not ideal. 14:52:33 mike: It's not just an image issue. There's currently no tool I've found that can BMF wrap 14:52:52 ... any TTML. 14:53:39 nigel: I thought gpac can do that - it certainly can do EBU-TT-D though I'm not sure about 14:53:42 ... other profiles of TTML. 14:54:53 nigel: Is there any spec implication for IMSC from that conversation? 14:54:57 pal: I didn't see any. 14:55:10 mike: I have a question: there are lots of provisions in IMSC 1 that say the content shall not 14:55:25 ... contain X. I'm wondering whether strategically that is a good thing to do in other profiles. 14:55:42 ... Architecturally it's interesting that there are a handful of forbidden things but nothing 14:55:49 ... is forbidden in other namespaces. 14:56:09 glenn: I think it's consistent with what EBU-TT-D did which seems to be extremely restrictive 14:56:19 ... on what content can be present, presumably to simplify clients. It's an interesting point. 14:56:32 ... When we added support for IMSC 1 to the TTV tool mostly what we added was checks for 14:56:50 ... restrictions, so as far as I'm aware IMSC 1's restrictions are fully checked by TTV right now. 14:57:13 mike: There's no question that a validator should check the spec. I'm not trying to revisit IMSC1. 14:57:31 ... Some people want implementations that support things not in the spec, so that's fine. 14:57:51 ... But you can add another namespace and that's fine. 14:58:02 glenn: Because IMSC 1 also says that any error handling is implementation dependent then 14:58:14 ... the normative requirement to prohibit things is very weak. An implementation may choose 14:58:27 ... to ignore them or not. It's useful to note that the core conformance in TTML says "ignore 14:58:32 ... everything you don't understand" basically. 14:58:53 atai: It's an interesting design approach discussion for profiles. The idea for EBU-TT-D is 14:59:10 ... only things that can be decoded should go in the document. Other things added may 14:59:21 ... change the complete behaviour. That's one approach and that gives the decoder a guarantee 14:59:34 ... that if it's a conformant file then there's only understandable content that can be decoded. 15:01:05 mike: It's consistent at least in EBU-TT-D but I'm throwing it out there that there's an 15:01:10 ... inconsistency in general in TTML profiles. 15:01:32 atai: There's a question what an IMSC decoder should do when unexpected vocabulary is found. 15:01:49 ... As Glenn says one option is to say "ignore" and "don't use" foreign content. 15:02:09 glenn: I said "vocabulary that the implementation doesn't understand" not "that the spec does not permit". 15:02:22 ... So some implementations can have specific additions. 15:02:35 atai: This is also important to get some experience back from implementations on which 15:02:40 ... design decisions work and which don't work. 15:02:53 Topic: AOB 15:03:03 mike: What's the status of the media registration now that the note has been updated? 15:03:27 nigel: I don't know. I've not heard anything. I'm happy to prompt Philippe to remind that we 15:03:42 ... consider the document ready for the next stage of registration. 15:04:52 nigel: It doesn't look like anything has changed at IANA since Feb 2014. 15:05:18 nigel: I'll remind Philippe. Thanks for merging those PRs. 15:05:36 mike: There are a couple of non-media-registration related issues, which I think were yours Nigel, which we should discuss at some point. 15:05:47 nigel: I'll revisit those and see if I can make any proposals. 15:06:35 nigel: OK we're out of time, thanks everyone. [adjourns meeting] 15:06:55 rrsagent, draft minutes 15:06:55 I have made the request to generate http://www.w3.org/2016/09/01-tt-minutes.html nigel 15:12:41 ScribeOptions: -final -noEmbedDiagnostics 15:12:43 rrsagent, draft minutes 15:12:43 I have made the request to generate http://www.w3.org/2016/09/01-tt-minutes.html nigel 17:02:42 Zakim has left #tt