- From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
- Date: Wed, 21 Sep 2016 07:40:37 +1000
- To: Thierry Michel <tmichel@w3.org>
- Cc: Public TTWG List <public-tt@w3.org>, David Ronca <dronca@netflix.com>, Nigel Megitt <nigel.megitt@bbc.co.uk>
- Message-ID: <CAHp8n2n8MfJ1ZS8O6LCDiReoMg-Eg0jba=o6pNz_HKafJS4wmA@mail.gmail.com>
Comments are in the bug tracker and in emails. All the information is available. It's a matter of collating it all together. Best Regards, Silvia. On 20 Sep 2016 6:57 PM, "Thierry MICHEL" <tmichel@w3.org> wrote: > > > Le 20/09/2016 à 00:07, Silvia Pfeiffer a écrit : > >> Yes, agreed. >> >> Wide review had been shown and feedback been received. >> > > > I am not aware of this. > > We indeed received comments/issues on the WebVTT spec. Some of these > comments have been discussed by the CG. > When and where was the wide review shown ? and feedback received from > commenters on the group resolution. > Is there a disposition of comments you could point to ? > > Best, > > Thierry. > > > I think it's with > >> the WG to make the next move. >> >> Best Regards, >> Silvia. >> >> >> On 20 Sep 2016 7:30 AM, "Thierry MICHEL" <tmichel@w3.org >> <mailto:tmichel@w3.org>> wrote: >> >> Sylvia, David, >> >> To clarify the W3C Process ... >> >> To *enter CR*, the TTWG must show that there is a wide review. >> About a year ago, different groups (I18N, WAI, CCS, etc.) have >> raised their issues on the WD. Each comment needs to be adressed >> (some have been by the CG) get consensus and resolution from the >> TTWG, and get agreement from the commenters. >> So currently the TTWG can't request CR publication of WebVVT. >> >> Once this task is done, the TTWG may request CR publication to the >> Director. >> >> Then, to *exit CR*, it requires to have 2 implementations of every >> feature in the specification. >> >> Best, >> >> Thierry. >> >> >> >> Le 19/09/2016 à 22:50, David Ronca a écrit : >> >> CR requires 2 implementations of every feature in the >> specification, >> correct? >> >> D >> >> On Mon, Sep 19, 2016 at 1:30 PM, Silvia Pfeiffer >> <silviapfeiffer1@gmail.com <mailto:silviapfeiffer1@gmail.com> >> <mailto:silviapfeiffer1@gmail.com >> <mailto:silviapfeiffer1@gmail.com>>> wrote: >> >> There's nothing stopping the group to decide to move WebVTT >> to CR >> right now. Why not just get it done? >> >> Best Regards, >> Silvia. >> >> >> On 20 Sep 2016 3:33 AM, "Nigel Megitt" >> <nigel.megitt@bbc.co.uk <mailto:nigel.megitt@bbc.co.uk> >> <mailto:nigel.megitt@bbc.co.uk >> <mailto:nigel.megitt@bbc.co.uk>>> wrote: >> >> Thanks all for a very productive first day of our Lisbon >> TPAC >> face to face meeting. Minutes can be found in html format >> at https://www.w3.org/2016/09/19-tt-minutes.html >> <https://www.w3.org/2016/09/19-tt-minutes.html> >> <https://www.w3.org/2016/09/19-tt-minutes.html >> <https://www.w3.org/2016/09/19-tt-minutes.html>> >> >> We made 1 resolution: >> >> *RESOLUTION: If we do not move WebVTT to CR in this >> Charter >> period then we will not include it in any new Charter.* >> >> >> The review period for this resolution under our Decision >> Process >> ends on Monday 3rd October. >> >> Minutes in text format: >> >> [1]W3C >> >> [1] http://www.w3.org/ >> >> Timed Text Working Group Teleconference >> >> 19 Sep 2016 >> >> See also: [2]IRC log >> >> [2] http://www.w3.org/2016/09/19-tt-irc >> <http://www.w3.org/2016/09/19-tt-irc> >> <http://www.w3.org/2016/09/19-tt-irc >> <http://www.w3.org/2016/09/19-tt-irc>> >> >> Attendees >> >> Present >> Rohit, Nigel, Glenn, Thierry, Dae, Andreas, >> David, >> Pierre >> >> Regrets >> Chair >> Nigel >> >> Scribe >> nigel >> >> Contents >> >> * [3]Topics >> 1. [4]Agenda bash >> 2. [5]Plan for Joint Meeting with Web & TV IG >> 3. [6]WebVTT stuff >> 4. [7]Tagging >> 5. [8]TTML1 Errata >> 6. [9]TTML2 Pull Requests >> 7. [10]IMSC 2 >> 8. [11]Agenda bash >> 9. [12]TTML2 implementation work >> * [13]Summary of Action Items >> * [14]Summary of Resolutions >> >> __________________________________________________________ >> >> <scribe> scribe: nigel >> >> Agenda bash >> >> group: [discusses topics on meeting page >> >> [15]https://www.w3.org/wiki/TimedText/tpac2016#Schedule >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule> >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule>> >> >> [15] >> https://www.w3.org/wiki/TimedText/tpac2016#Schedule >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule> >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule >> <https://www.w3.org/wiki/TimedText/tpac2016#Schedule>> >> >> <glenn> +Present Glenn >> >> nigel: Seems like the topics list is pretty close to >> the order >> we want to cover stuff in. >> >> Plan for Joint Meeting with Web & TV IG >> >> nigel: We are meeting the Web & TV IG at 11, so need >> to provide >> an update etc. >> ... Discusses proposal for Web & TV IG consisting of >> update on >> our work in TTML, >> ... audio description requirements, issue of >> relationship >> between encoded video, media player >> ... and timed text presentation; live contribution >> and BBC >> subtitle guidelines. (last two points from Nigel with a >> different hat on!) >> >> andreas: I have some slides to discuss on TextTrackCue >> interface support for different formats in HTML5. >> ... I would also point to the unconference session on >> this on >> Wednesday. They may also >> ... want to log this as work that needs doing by a >> Web & TV IG >> task force. >> >> nigel: Good idea, let's do that ahead of my stuff on >> AD, live >> contribution etc. >> >> andreas: [Previews slides] including missing MIME >> type on track >> element in HTML5 >> >> nigel: Thanks, let's do that after the TTWG update and >> if >> there's time to hand back to me for the other parts >> then let's >> do that. >> >> WebVTT stuff >> >> david: Number one priority is to find a new Chair to >> cover this >> topic - I've indicated already to >> ... plh etc that I don't have the time to devote to >> this. >> >> glenn: What's the status of implementation work? >> >> david: At Apple it's bug fixing, keeping up with >> customers. >> >> glenn: On the Chrome and webkit list I don't see much >> activity. >> I am not following mozilla or Edge. >> ... What's the status in other groups e.g. MPEG >> referencing >> WebVTT? >> >> david: The Chair does need to make progress on moving >> it to Rec >> so it can be normatively referenced. >> ... There is implementation work excluding region >> support in >> many implementations. >> >> andreas: I think there have been updates to the >> specification >> that have not been reflected in >> ... implementations so this is a problem. >> >> nigel: I've noticed that too - Simon made some really >> good >> changes around 10-11 months ago, >> ... which i suspect have not been implemented. I'm >> not sure >> about the status of editing to >> ... address the readability review feedback. >> >> david: Apple's implementations predate those changes. >> >> andreas: It's hard to know if those changes will ever >> make it >> into implementations. >> >> nigel: From a BBC perspective there are features that >> are >> essential for accessibility that look >> ... like they would have to be put at risk for CR due >> to lack >> of implementation, so that would >> ... be a "red flag" for me. >> ... For example the BBC's editorial guidelines at >> [16]http://bbc.github.io/subtitle-guidelines/ >> <http://bbc.github.io/subtitle-guidelines/> >> <http://bbc.github.io/subtitle-guidelines/ >> <http://bbc.github.io/subtitle-guidelines/>> >> ... cannot I believe be met by most implementations >> of WebVTT >> right now. >> >> [16] http://bbc.github.io/subtitle-guidelines/ >> <http://bbc.github.io/subtitle-guidelines/> >> <http://bbc.github.io/subtitle-guidelines/ >> <http://bbc.github.io/subtitle-guidelines/>> >> >> action-475? >> >> <trackbot> 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 >> >> <trackbot> >> >> [17]http://www.w3.org/AudioVideo/TT/tracker/actions/475 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475>> >> >> [17] >> http://www.w3.org/AudioVideo/TT/tracker/actions/475 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/475>> >> >> nigel: oops I meant: >> >> action-473? >> >> <trackbot> action-473 -- Thierry Michel to Contact >> co-chairs >> and essential parties on how to move forward on vtt; >> need an >> action plan -- due 2016-06-30 -- OPEN >> >> <trackbot> >> >> [18]http://www.w3.org/AudioVideo/TT/tracker/actions/473 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473>> >> >> [18] >> http://www.w3.org/AudioVideo/TT/tracker/actions/473 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/473>> >> >> nigel: Thierry did this, but I don't believe we have >> an action >> plan. >> >> david: We need a suitable volunteer to go through the >> review >> comments and respond. >> >> thierry: The Community Group has looked into the review >> feedback - about 30 comments >> ... have been discussed: that's the current status. >> Now those >> comments need to be approved >> ... by the TTWG (and discussed) and then we should >> send those >> responses to the commenters. >> ... At some point we need to coordinate between the >> CG and the >> WG to progress those. >> ... This has not changed for more than a year, >> probably because >> some people involved have >> ... left and Simon does not participate actively in >> the WG. We >> are experiencing joint work with >> ... a CG and a WG and we need to invent a process to >> deal with >> this. >> >> nigel: This works both ways - the WG also has not >> scheduled any >> effort to work on this. >> >> andreas: I'm not really convinced that the CG exists >> as a >> traditionally defined group. >> >> nigel: Shall we close the action? The "contact the >> chairs" part >> is done, we're missing an action plan. >> >> david: Leave it open. >> >> action-473: Discussed in TTWG F2F 2016-09-19 - need a >> volunteer >> to progress this, possibly a new Chair. >> >> <trackbot> Notes added to action-473 Contact >> co-chairs and >> essential parties on how to move forward on vtt; need >> an action >> plan. >> >> action-396? >> >> <trackbot> action-396 -- David Singer to Produce >> evidence of >> request for wide review for webvtt, for the archive >> -- due >> 2015-04-17 -- OPEN >> >> <trackbot> >> >> [19]http://www.w3.org/AudioVideo/TT/tracker/actions/396 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396>> >> >> [19] >> http://www.w3.org/AudioVideo/TT/tracker/actions/396 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396> >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396 >> <http://www.w3.org/AudioVideo/TT/tracker/actions/396>> >> >> david: I have not yet done this. >> >> action-396: TTWG F2F meeting 2016-09-19: David has >> not been >> able to do this yet. >> >> <trackbot> Notes added to action-396 Produce evidence >> of >> request for wide review for webvtt, for the archive. >> >> nigel: TO be controversial/challenging, WebVTT has >> been on our >> Charter since 2013 and we >> ... have made very little progress. Should we drop it? >> >> david: If we don't complete it in this Charter period >> [end >> March 2018] then we should not >> ... recharter it - I propose that as a resolution. >> >> PROPOSAL: If we do not make progress on moving WebVTT >> to >> Recommendation in this Charter period we do not intend >> to >> include it on any rechartering. >> >> thierry: That's a final step - I think we should be >> aiming to >> move to CR well before that. >> >> david: I agree. >> >> glenn: We could publish it as a WG Note, to make it >> easier for >> external people to reference. >> >> nigel: This is a lot easier. >> >> thierry: That would probably be a final step to that >> work. >> >> nigel: In fact publishing a Note is a process >> requirement if we >> stop working on it. >> >> thierry: We would do that if we removed it from the >> Charter. >> >> glenn: It would be helpful to have a document that >> does not >> have the word "Draft" in it. >> >> thierry: I'm happy to help with the wide review; >> that's one >> thing. The second thing is the CR. >> ... We could stay in CR for a couple of years and >> monitor >> implementation work, or we could >> ... remove non-implemented features. Right now there >> are a lot >> of features that are not >> ... implemented. That's something we could do in >> parallel. >> Maybe it is not useful to have >> ... comments on features that we are likely to drop. >> >> nigel: I want to signal that if we have to drop >> features that >> are essential for accessibility then >> ... I will have to object to it progressing. >> >> thierry: There's also a lack of specification text on >> integrating CSS. We could maybe save time >> ... by not addressing issues that we know are >> unlikely to be >> implemented in the next two years. >> >> group: discussion about who is interested in >> contributing to >> implementation work etc and therefore progressing >> responses to >> comments. >> >> RESOLUTION: If we do not move WebVTT to CR in this >> Charter >> period then we will not include it in any new Charter. >> >> andreas: We could mention the TTML to WebVTT mapping >> document >> in the Web & TV IG meeting. >> ... We published it last year and are awaiting >> implementation >> comments. We are waiting for a >> ... stable reference for WebVTT in order to proceed. >> >> thierry: You would expect to see at least a CR >> document? >> >> andreas: CR would clearly indicate a stable set of >> features you >> can map against. >> >> Tagging >> >> david: DASH and the MP4 file format have a way to tag >> the kind >> of role of a track, using a URI >> ... to identify the vocabulary used, and then a term >> from that >> vocabulary. I need a URI to >> ... refer to the @kind vocabulary in the HTML5 >> specification, >> and there isn't one. >> >> pierre: There is one but it is not complete, >> specified in DASH. >> >> david: It is not specified in the HTML document itself. >> >> pierre: That's correct. As long as we can reference >> the one in >> DASH that can be used. >> >> david: Agreed there is a DASH vocabulary. >> >> pierre: So the request to add one to HTML is not >> required for >> MPEG CMAF because the DASH one can be used. >> >> david: I got agreement from WHATWG and the Web >> Platform WG for >> about:html-kind as the URI >> ... that refers to the @kind vocabulary in the HTML >> specification. >> ... And I have registered that with IANA. >> ... I'm waiting for that URI to appear in a revision >> of the Web >> Platform docs. When it is then >> ... I will update the IANA form. >> >> nigel: It's good to have that but I would note that >> in my view >> the kind vocabulary is terrible. >> >> glenn: There are some semantics associated, such as >> prevention >> of display of metadata tracks by the UA. >> >> david: I would agree that the HTML vocabulary is both >> under- >> and over-specified simultaneously! (in different ways) >> >> nigel: In my view it is insufficiently rich to >> describe the >> purpose and intent of the track data. >> >> pierre: It would be great if as making the HTML >> vocabulary more >> official we could also fix it. >> >> david: I support that. >> ... CMAF does prefer DASH at the moment - it says to >> use the >> DASH term if it supports what you want to do. >> >> nigel: I also note that we have not addressed how to >> extract >> something equivalent to kind >> ... within a timed text document so that it can be >> extracted >> and used to embed into a host HTML page. >> ... We did address language recently, but not kind. >> >> david: Some people want to manage external manifest >> files, but >> I'm in favour of self describing documents. >> ... I'm also aware of ongoing discussions about tags >> for easy >> to read captions (mandated by FCC) and karaoke. >> >> pierre: There is a very specific definition of those >> two terms >> in karaoke. >> >> glenn: In TTML2 we have a named metadata item for >> easy reader. >> There's nothing on karaoke per se. >> ... nothing that uses that term in TTML2. >> >> nigel: [adjourns for a break] - let's meet in >> Auditorium IV at >> 1100 for our update to Web & TV IG. >> >> <nigel_> nigel: Joint meeting - see #webtv >> >> TTML1 Errata >> >> nigel: Are there any other errata other than for >> backgrounds on >> spans and lines? >> >> pierre: The only thing I'd mention is that the >> computed style >> resolution for % is very well defined >> ... but the computed style for em is not so clear >> when you say >> e.g. tts:fontSize="2em" but >> ... that is with respect to the current font size but >> that is >> not well defined in TTML1. I assume >> ... it is relative to the parent element's font size >> but it >> does not say that clearly. >> >> glenn: I would consult TTML1 and then go back and >> reference >> XSL-FO which would take me >> ... to CSS2. Without having done a recent review of >> that I >> don't know off the top of my head >> ... but I'm pretty sure you're right - it would have >> to make >> use of the computed font size of >> ... the parent element. >> >> pierre: Notice that we already have issue #206 on the >> ttml1 >> repo which is a bug about >> ... specifying em units for fontSize on region. >> >> nigel: That sounds very similar. >> >> glenn: Right now there are 23 open issues on TTML1 so >> I would >> expect that there are some >> ... errata to be written for those and they probably >> also need >> to be fixed in TTML 2 also. >> >> pierre: I can go ahead and create an issue for this. >> >> glenn: Go ahead - also refer to #206 - it may be >> related but >> more general. >> ... I think I propose that it should be in relation >> to 1c. >> >> pierre: That was my first thought, but looking at >> XSL-FO I >> think it is probably more like %. >> >> nigel: Okay, so the one on the agenda is: >> [20]https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209> >> <https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209>> >> >> [20] https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209> >> <https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209>> >> >> andreas: I think there has not been much progress >> since we last >> discussed it. We said we need >> ... more investigation to find a good solution. I >> want to point >> to something related. >> ... This problem about gaps between lines has been >> addressed by >> the HbbTV 2.0.1 spec >> ... which a lot of televisions will implement. At the >> moment >> that is not really interoperable >> ... and compatible with IMSC 1 so we should pay >> attention to >> it. >> ... References spec text from HbbTV 2.0.1 that, >> specific to >> EBU-TT-D 1.0 defines that >> ... where the lineHeight is "normal" or <125% the >> background of >> each generated inline area >> ... shall be rendered such that there are no gaps >> between the >> rendered backgrounds of >> ... adjacent lines. >> >> glenn: We have a quasi default of doing what CSS >> does, which is >> different from what this suggests. >> ... This mandates behaviour that is at variance with >> the XSL-FO >> and CSS behaviour. >> >> andreas: Yes. >> >> glenn: By the way issue #209 on the TTML spec has a >> length >> discussion on this. >> ... The bottom line in my reading is that the height >> of an >> inline area in CSS is implementation defined. >> ... Different implementations have fine tuned >> themselves to be >> consistent with each other, outside of any spec. >> >> nigel: You can see an editorial requirement example >> of this at >> >> [21]http://bbc.github.io/subtitle-guidelines/#Background-size >> <http://bbc.github.io/subtitle-guidelines/#Background-size> >> >> <http://bbc.github.io/subtitle-guidelines/#Background-size >> <http://bbc.github.io/subtitle-guidelines/#Background-size>> >> >> [21] >> http://bbc.github.io/subtitle-guidelines/#Background-size >> <http://bbc.github.io/subtitle-guidelines/#Background-size> >> >> <http://bbc.github.io/subtitle-guidelines/#Background-size >> <http://bbc.github.io/subtitle-guidelines/#Background-size>> >> >> glenn: I agree that we need to nail this down - also >> see issue >> #212 in TTML1. >> >> nigel: [22]https://github.com/w3c/ttml1/issues/212 >> <https://github.com/w3c/ttml1/issues/212> >> <https://github.com/w3c/ttml1/issues/212 >> <https://github.com/w3c/ttml1/issues/212>> >> ... [23]https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209> >> <https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209>> >> >> [22] https://github.com/w3c/ttml1/issues/212 >> <https://github.com/w3c/ttml1/issues/212> >> <https://github.com/w3c/ttml1/issues/212 >> <https://github.com/w3c/ttml1/issues/212>> >> [23] https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209> >> <https://github.com/w3c/ttml1/issues/209 >> <https://github.com/w3c/ttml1/issues/209>> >> >> pierre: A browser based CSS implementation would >> display a gap? >> >> glenn: Correct >> >> andreas: There are scripting techniques for getting >> around >> this. >> >> pierre: If we feel this is a common requirement for >> accessibility then it needs to be addressed in the CSS >> WG >> >> glenn: I've had a detailed offline discussion with >> Bert Bos >> about this and he pointed out that >> ... one of the advanced level 4 modules might at some >> point be >> able to deal with this. >> ... There are a whole bunch of assumptions in CSS on >> inline >> non-replaceable areas, for example >> ... you cannot specify the content height manually. >> The height >> property explicitly does not >> ... apply. That was the first problem we ran into, >> because we >> wanted the height of the content >> ... box to extend to the line area. Somewhere I >> proposed a mode >> for the style engine to use >> ... different semantics for the height of content >> areas. The >> question is can you have a profile >> ... that defaults the parameter to a particular value. >> >> nigel: The pressing need here is to issue some >> statement on >> this for TTML1. >> >> piere: I recall that some people use a style where >> they do >> actually want the gap. >> >> andreas: yes, for example if you have the lineheight >> at 200% >> you don't want such a big background area. >> >> pierre: In CSS can you always add padding to every >> line? >> >> glenn: You can but the problem is you cannot determine >> at >> authoring time what value to add. >> ... At first order we should document more carefully >> what the >> current situation is in TTML1. >> ... That may allow people to come up with no-gap >> semantics. We >> could define the default >> ... semantics to be the no-gap scenario but if we do >> that we >> need to allow the author to define >> ... the other behaviour. If we change the default now >> what >> would that break? >> >> nigel: I understand that the content rectangle is not >> well >> defined? >> >> glenn: It is not, but all the browser implementations >> do it >> roughly the same way. >> >> nigel: Could we add an informative note via an >> erratum to say >> that the content rectangle is >> ... not well defined but is commonly implemented so >> that it >> does not go to the line height? >> >> pierre: That's not what I'm hearing. I think CSS needs >> to >> address this. >> >> glenn: I'm worried that we cannot easily go back and >> retroactively define the content height >> ... to never show a gap. >> >> pierre: It would be easier to do that if it were not >> that some >> folk like the gap. >> >> glenn: In TTML2 we can add a new mode that drives >> that, but in >> TTML1 what can we do? >> >> andreas: This requirement for no gaps came from >> accessibility >> guidelines to get proper presentation. >> ... The minimum we could say is that some >> specifications could >> define this. >> >> pierre: If someone is overriding that rendering it >> needs to be >> flagged. >> >> andreas: That will not change, I think this is more of >> an >> interoperability problem. >> ... There is an initial step e.g. for an IMSC 1.1, >> and then a >> long term TTML2 solution. >> ... For now we should say something about this in >> TTML1. >> >> pierre: +1 >> >> andreas: I would also hope for a liaison to respond >> to this. >> >> glenn: We can note that the algorithm for content >> height is not >> concretely defined and that >> ... browsers do behave the same with current CSS >> implementations and will introduce a gap. >> ... If we do want a new TTML1 feature we could write >> a short >> specification introducing a >> ... ttsx namespace style that is interpreted in a >> particular >> way. >> >> andreas: Ideally if there is a proper parameter to >> control this >> it should be defined in this group. >> >> nigel: +1 >> >> glenn: That would be an official extension to TTML1, >> which we >> could say maps to a particular >> ... syntax and semantic in TTML2. >> ... That might be an approach. >> >> pierre: If there is an urgent need to address real >> problems we >> should address it in IMSC 1.1. >> >> glenn: I've heard 3 things: 1. Clarify TTML1 with an >> errata - >> we can do that non-controversially. >> ... 2. We can define new mechanisms in TTML2 - we can >> do that >> no problem. >> ... 3. More controversially, define a new extension >> style for >> TTML1. That creates another fork >> ... in the implementation space. >> >> andreas: The target when this was discussed was an >> IMSC 1.1 >> version. If that is possible we >> ... should do that. >> >> pierre: Absolutely. The question is if there is an >> urgent need >> to resolve an industry problem now. >> ... The worst thing would be to make a change that >> does not >> solve the problem. >> >> andreas: HbbTV has solved this for now - it would be >> interesting to know if this breaks >> ... current implementations. >> >> pierre: it would be good to have a formal >> communication with >> HbbTV about this issue. >> ... It is essential that HbbTV is encouraged to >> communicate >> their requirements to this group and we should be >> welcoming of >> this, even if we make the initial communication. >> >> andreas: We should also be clear that it is needed for >> interoperability to establish this communication >> channel. >> >> nigel: Notes that independent of HbbTV the BBC raised >> this >> issue on TTML2 and andreas opened the equivalent on >> TTML1. >> ... I want to come back to what we can do here. >> >> andreas: There's the formal comms with HbbTV, an >> errata for >> TTML1, and a discussion about >> ... how to fix for TTML2. If there is no formal >> requirement for >> this then it will not happen in IMSC 1. >> >> pierre: BBC has raised this for TTML2, but the >> timescale for >> that is very different than for TTML1. >> ... To make a change on TTML1 requires a higher >> threshold, so >> if there is a group such as >> ... HbbTV that needs this in the short term then we >> should do >> it. >> >> <scribe> ACTION: nigel Draft a liaison to HbbTV >> requesting >> further information and proposing an option e.g. to >> extend IMSC >> 1 to allow signalling of background height on span, >> and request >> timelines etc. [recorded in >> >> [24]http://www.w3.org/2016/09/19-tt-minutes.html#action01 >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01> >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01 >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01>>] >> >> [24] >> http://www.w3.org/2016/09/19-tt-minutes.html#action01 >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01> >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01 >> <http://www.w3.org/2016/09/19-tt-minutes.html#action01>>] >> >> <trackbot> Created ACTION-478 - Draft a liaison to >> hbbtv >> requesting further information and proposing an >> option e.g. to >> extend imsc 1 to allow signalling of background >> height on span, >> and request timelines etc. [on Nigel Megitt - due >> 2016-09-26]. >> >> nigel: Okay, that works; I would also still like to >> see the >> erratum on TTML1 to provide the context >> ... for any update to IMSC 1 to allow signalling this >> behaviour. >> >> glenn: I have added a comment on the issue at >> >> [25]https://github.com/w3c/ttml1/issues/209#issuecomment-247973 >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973> >> >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973 >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973>> >> 673 >> >> [25] >> https://github.com/w3c/ttml1/issues/209#issuecomment-247973673 >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973673> >> >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973673 >> <https://github.com/w3c/ttml1/issues/209#issuecomment-247973673>> >> >> nigel: Thank you! >> >> glenn: Of course that doesn't explain what to do >> about it, but >> that's for >> [26]https://github.com/w3c/ttml2/issues/150 >> <https://github.com/w3c/ttml2/issues/150> >> <https://github.com/w3c/ttml2/issues/150 >> <https://github.com/w3c/ttml2/issues/150>> >> ... We have consensus in TTLM2 to solve this? >> >> [26] https://github.com/w3c/ttml2/issues/150 >> <https://github.com/w3c/ttml2/issues/150> >> <https://github.com/w3c/ttml2/issues/150 >> <https://github.com/w3c/ttml2/issues/150>> >> >> nigel: Yes please! >> >> glenn: I have a bpd content proposal where I define 7 >> possible >> values. >> >> nigel: That may be more than we need - let's review. >> ... Thanks for the good discussion everyone, let's >> adjourn for >> lunch and return at 1400. >> >> TTML2 Pull Requests >> >> nigel: First up, >> [27]https://github.com/w3c/ttml2/pull/177 >> <https://github.com/w3c/ttml2/pull/177> >> <https://github.com/w3c/ttml2/pull/177 >> <https://github.com/w3c/ttml2/pull/177>> Add >> tts:background{Clip,Extent,Origin} >> >> [27] https://github.com/w3c/ttml2/pull/177 >> <https://github.com/w3c/ttml2/pull/177> >> <https://github.com/w3c/ttml2/pull/177 >> <https://github.com/w3c/ttml2/pull/177>> >> >> glenn: This is for image rendering support - I missed >> a couple >> of items from CSS: there is >> ... an editorial note to add them. >> ... I ended up using backgroundExtent rather than >> backgroundSize for consistency. >> >> nigel: Just a note on reviewing the PRs - they don't >> include >> the built HTML so it's hard to >> ... review or diff. I'd like a CI tool to build the >> HTML >> automatically so we can review it. >> >> glenn: I could do the build and check in the built >> HTML but >> then on pulling I would have to >> ... remove it and build it again for gh-pages. >> ... I'll go ahead and make a change to make these >> easier to >> review. >> >> <glenn> >> >> [28]https://www.w3.org/TR/css3-background/#the-background-origi >> <https://www.w3.org/TR/css3-background/#the-background-origi> >> >> <https://www.w3.org/TR/css3-background/#the-background-origi >> <https://www.w3.org/TR/css3-background/#the-background-origi>> >> n >> >> [28] >> https://www.w3.org/TR/css3-background/#the-background-origin >> <https://www.w3.org/TR/css3-background/#the-background-origin> >> >> <https://www.w3.org/TR/css3-background/#the-background-origin >> <https://www.w3.org/TR/css3-background/#the-background-origin>> >> >> nigel: So now we have backgroundOrigin as well as >> backgroundPosition? >> >> glenn: We may want to rename these! >> >> nigel: (notes that this looks analogous to origin and >> position >> but is not) >> >> glenn: backgroundOrigin defines where the background >> is drawn >> relative to the content. >> ... This is as defined in CSS3 backgrounds and >> borders - it's >> the same semantic. >> ... I took off the -box suffix that's on CSS3. >> >> nigel: I sense that there are some changes needed >> here to clear >> up the names and make them >> ... less potentially confusing. Also I'd encourage >> review of >> this in the context of IMSC 2 >> ... if we want to support image placement in more >> detail. >> >> pierre: This does not express how you would use SMPTE >> background image in IMSC 1. >> >> glenn: That's actually mapped to the image element. >> >> pierre: yes. >> >> glenn: However we did define background image also in >> TTML2 and >> these attributes >> ... I believe fully define the semantics for >> background images. >> ... In the case of a foreground image these don't come >> up >> because they define the content >> ... rectangle. There's never a box in which to >> position it - >> that only applies when the image >> ... is used for the background. Also bear in mind that >> background images may be repeated >> ... in x and y directions, which can never happen with >> foreground images. >> ... For foreground image size you would use bpd and >> ipd rather >> than backgroundExtent. >> ... I need to think if it would ever be applicable to >> have the >> same semantic as backgroundExtent >> ... on a foreground image. I want to see if CSS >> allows that >> property on the image element >> ... in HTML and what does it mean. >> >> nigel: Just considering the use cases for this - one >> that comes >> to mind is the use of a >> ... graduated fill background image that is animated >> to move >> along behind foreground text >> ... for karaoke usage. Do these semantics support that? >> >> glenn: Yes I think you could animate the x and y >> positions, >> either discretely or continuous. >> >> nigel: The conclusions for the time being are 1) that >> more >> thinking is needed for the names >> ... and 2) whether backgroundExtent can apply to >> foreground >> images. >> ... For the hard of thinking, some example images etc >> would >> really help, since the terminology >> ... has a lot of repetition that makes it hard to >> understand >> the differences. >> ... I've added some notes to the issue. >> ... Moving on to Add support for rounded borders by >> introducing >> <border-radii> compone… >> ... [29]https://github.com/w3c/ttml2/pull/179 >> <https://github.com/w3c/ttml2/pull/179> >> <https://github.com/w3c/ttml2/pull/179 >> <https://github.com/w3c/ttml2/pull/179>> >> >> [29] https://github.com/w3c/ttml2/pull/179 >> <https://github.com/w3c/ttml2/pull/179> >> <https://github.com/w3c/ttml2/pull/179 >> <https://github.com/w3c/ttml2/pull/179>> >> >> nigel_and_glenn: [discussion of single value processor >> semantics for border radii without consensus emerging] >> >> glenn: The more interesting case is the one raised in >> the issue >> [30]https://github.com/w3c/ttml2/issues/176 >> <https://github.com/w3c/ttml2/issues/176> >> <https://github.com/w3c/ttml2/issues/176 >> <https://github.com/w3c/ttml2/issues/176>> >> >> [30] https://github.com/w3c/ttml2/issues/176 >> <https://github.com/w3c/ttml2/issues/176> >> <https://github.com/w3c/ttml2/issues/176 >> <https://github.com/w3c/ttml2/issues/176>> >> >> > > ...
Received on Tuesday, 20 September 2016 21:41:16 UTC