14:55:53 RRSAgent has joined #tt 14:55:53 logging to http://www.w3.org/2014/12/18-tt-irc 14:55:55 RRSAgent, make logs public 14:55:55 Zakim has joined #tt 14:55:57 Zakim, this will be TTML 14:55:57 ok, trackbot; I see SYMM_TTWG()10:00AM scheduled to start in 5 minutes 14:55:58 Meeting: Timed Text Working Group Teleconference 14:55:58 Date: 18 December 2014 14:57:55 SYMM_TTWG()10:00AM has now started 14:58:04 +nigel 14:58:17 Present+ nigel 14:58:20 chair: nigel 14:59:13 + +1.720.897.aaaa 14:59:37 mike has joined #tt 15:00:06 +Mike 15:00:48 Present+ glenn, Mike 15:01:00 zakim, aaaa is glenn 15:01:00 +glenn; got it 15:02:23 pal has joined #tt 15:02:25 tmichel has joined #tt 15:03:13 +[IPcaller] 15:03:42 zakim, pal is [IPcaller] 15:03:42 sorry, pal, I do not recognize a party named 'pal' 15:03:55 zakim, IPcaller is pal 15:03:55 +pal; got it 15:04:11 +??P11 15:04:23 Present+ pal, tmichel 15:04:27 zakim ??P11 is me 15:04:36 zakim, ??P11 is me 15:04:36 +tmichel; got it 15:04:36 zakim, ??P11 tmichel 15:04:38 I don't understand '??P11 tmichel', nigel 15:05:36 zakim, ??P11 is tmichel 15:05:36 I already had ??P11 as tmichel, glenn 15:07:30 scribeNick: nigel 15:07:42 Regrets: Frans, andreas 15:07:48 zakim, who's noisy? 15:07:52 Topic: This meeting 15:07:57 zakim, who is making noise? 15:07:59 glenn, listening for 10 seconds I heard sound from the following: tmichel (76%) 15:08:07 zakim, mute tmichel 15:08:07 tmichel should now be muted 15:08:09 nigel, listening for 10 seconds I heard sound from the following: nigel (39%), tmichel (71%) 15:08:55 nigel: introduces agenda 15:09:08 nigel: Is there any other business? 15:09:32 pal: I'd like to review the TTML2 timeline and the IMSC 1 timeline if there's time at the end, and perhaps 15:09:39 ... start to think about IMSC 2 timeline. 15:10:01 ... and how long it takes to complete PR review, i.e. PR -> Rec 15:10:23 ... This is because there are other organisations that are considering using those specs. 15:10:27 atai has joined #tt 15:10:52 Topic: Action Items 15:10:57 action-359? 15:10:57 action-359 -- Thierry Michel to Draft a message re imsc 1 cr test suite and implementation and a list of bodies to send it to. -- due 2014-12-18 -- OPEN 15:10:57 http://www.w3.org/AudioVideo/TT/tracker/actions/359 15:11:25 zakim, unmute tmichel 15:11:25 tmichel should no longer be muted 15:11:53 tmichel: I sent the message, and copied to the member-tt list and I sent it to all the people that are listed 15:12:09 ... on our charter as liaison and the others to whom Nigel sent the wide review messages, and two 15:12:14 ... coordination groups. 15:12:24 ... I copied pal, plh, nigel and dsinger. 15:12:39 close action-359 15:12:39 Closed action-359. 15:12:46 action-360? 15:12:46 action-360 -- Nigel Megitt to Send liaison request on behalf of w3c ttwg to arib -- due 2014-12-18 -- OPEN 15:12:46 http://www.w3.org/AudioVideo/TT/tracker/actions/360 15:13:09 nigel: I have begun drafting this and have addresses for the recipients - they have requested a paper 15:13:20 ... document requesting the liaison. I have more to do on this. 15:14:32 Topic: Issues 15:15:40 issue-21? 15:15:40 issue-21 -- window anchor points not supported? -- pending review 15:15:40 http://www.w3.org/AudioVideo/TT/tracker/issues/21 15:16:10 glenn: I haven't received any comments on any of the issues that I've marked as Pending Review 15:16:50 ... I guess most likely people haven't had a chance to dive into it. I suggest we close this and if an issue 15:16:55 ... arises then it can be filed. 15:17:23 close issue-21 15:17:23 Closed issue-21. 15:17:29 issue-236? 15:17:29 issue-236 -- Character spacing, i.e. letter-spacing -- pending review 15:17:29 http://www.w3.org/AudioVideo/TT/tracker/issues/236 15:18:08 glenn: this is based on the CSS attribute of the same name, so should be quite straightforward. 15:18:30 glenn: This was to define a property to control tracking and to allow the tracking value to be 15:18:50 ... specified, a typographic term that refers to the spacing between characters. There's a 15:19:06 ... related issue called kerning. It turns out that one of the Japanese deployed specifications has 15:19:23 ... an attribute to turn on and off kerning. Japanese doesn't usually use kerning, but it may be 15:19:42 ... useful for embedded latin scripts. To support that we need to have a property font-kerning 15:19:53 ... as specified in the CSS3 font module - I'll add an issue for that. 15:20:06 Action: glenn Raise an issue for font-kerning in TTML2 15:20:06 Created ACTION-362 - Raise an issue for font-kerning in ttml2 [on Glenn Adams - due 2014-12-25]. 15:20:25 close issue-236 15:20:25 Closed issue-236. 15:20:31 issue-237? 15:20:31 issue-237 -- Inline space -- pending review 15:20:31 http://www.w3.org/AudioVideo/TT/tracker/issues/237 15:20:47 +Andreas 15:20:57 Present+ Andreas 15:21:22 glenn: This allows the author to define a space in the inline progression direction. 15:21:38 close issue-237 15:21:38 Closed issue-237. 15:22:04 nigel: Last week we could not close a number of issues related to the ttm:item solution. 15:22:54 ... There has been some discussion - I'd like us to get to sufficient consensus for FPWD, even if 15:23:04 ... later we modify it based on further discussion, e.g. prior to CR. 15:23:39 glenn: There were 2 issues raised - one related to validation of the content of the item element, 15:24:15 ... noting that we don't have a constraint that all spec items can be validated by XML Schema. 15:24:30 ... Though I guess that a constraint based on the content type of ttm:item based on the name 15:24:51 ... and a lookup may be validatable using Schema 1.1. 15:25:01 nigel: Really? 15:25:17 glenn: It would have to have name -> type dereferencing logic. I haven't tried it. 15:25:39 glenn: The other issue is regarding the value definition of names. Nigel proposed that we should 15:26:15 ... find a way to [scribe misses audio]. The most appropriate mechanism I think is to use 15:26:31 ... the xml namespace mechanism, to allow a prefix to qualify the name, where the prefix 15:26:45 ... can be resolved to a URI that doesn't have to be reused every time (i.e. it's inherited). So I 15:27:04 ... propose to change the syntax of name to NCName or an unqualified name - if an unqualified 15:27:19 ... name then it would be implied to be within the TTML namespace definition, e.g. the "TT 15:27:39 ... metadata items namespace". For people who want to define an alternate namespace for a 15:27:54 ... defining authority or classification scheme, then e.g. "ebuttm:" could be used and then 15:28:09 ... somewhere in the document associate that namespace with the prefix. Then the name value 15:28:30 ... in ttm:item would be name="ebuttm:whatever". That's my suggested way to handle name 15:28:41 ... extension mechanisms and to have a shorthand for the prefix mechanism. 15:29:04 Andreas: In general I think that's a reasonable concept proposal, and will be worth reviewing. 15:29:17 ... For me, this is a complete concept to integrate metadata in TTML without dependent on the 15:29:37 ... TTML publication process. I can see the reasoning to find a way to handle metadata independently 15:29:50 ... of the rest of the specification. I don't want to block the FPWD process though I think it 15:29:58 q+ 15:30:11 ... does need more review. I think this should be put into the WD and should be reviewed by 15:30:31 ... e.g. EBU to see how it matches with the current mechanism. Regarding validation, it would 15:30:42 ... be good to have a position about it, how important current validation mechanisms are for 15:31:05 ... standardisations of new items. From a practical view some validation mechanisms are more 15:31:58 ... used than others. I'd welcome other views on this as well as mine - are there other users 15:32:09 ... whose workflow depends on validation? 15:32:46 glenn: Thinking of the practical consequences of e.g. using XSD formally, and then we say that 15:33:03 ... we're going to interpret every TTML constraint that can be expressed in XSD then that would 15:33:20 q+ 15:33:26 ... be quite a task even for TTML1. For example the rules on the timing expression and a variety 15:33:48 ... of other expressions are just xs:string because writing out a regular expression or schema 15:34:03 ... syntax for some of the more complicated attributes may be extremely difficult - e.g. 15:34:34 ... length and time expressions. Regardless of RNC or XSD we didn't go as far as possible. We 15:34:57 ... ended up incorporating some of those - e.g. textDecoration has all possible combinations 15:35:14 ... enumerated in the schema, but in other cases it's difficult. The practical consequences of 15:35:34 ... pushing XML schema more. And we didn't have TTV for example available at that time. There's 15:35:52 ... a place for validators and verifiers that can go further than schema validators. 15:35:54 ack pal 15:36:08 pal: For metadata that is purely descriptive, why even create an equivalent in TTML2 and not 15:36:20 ... just encourage metadata to be added in foreign namespaces. 15:36:34 s/s./s? 15:36:55 glenn: We don't say anything about that - we imply that it's a reasonable approach. The reason 15:37:12 ... I chose to try to pull in the existing metadata that I could find between SMPTE-TT and EBU-TT 15:37:25 ... was because I think a lot of it has general utility to TTML and having it defined in one place 15:37:51 ... is a good thing to do. If we had gone down that path in TTML1, when we reviewed some 15:38:07 ... specific metadata items from Dublin Core and MPEG-7 we decided we weren't ready to 15:38:22 ... define them. Since then we've deployed, different groups have proposed specific metadata 15:38:34 ... items and I think now's the time to bring them into TTML unless there's a good reason not to. 15:38:45 ... That allows them to be commonly used. 15:39:04 pal: I appreciate the goal. I see a danger: e.g. CEA608CaptionService. The definition of that item 15:39:29 ... is substantively different than RP2052-10 that's supposed to be equivalent. How can we 15:39:44 ... avoid confusion between those two parameters that look like they're supposed to be the same? 15:40:00 atai: I see the same danger for EBU-TT vocabulary. 15:40:14 glenn: I want to know what the difference is because I tried to stay faithful to the existing 15:40:29 ... definitions where I put the prefix cea on them - I added that prefix because I recognised 15:40:44 ... that the way it was defined in the RP you referred to was quite specific to CEA608 and I 15:41:01 ... didn't think it was appropriate to make it more generic. I haven't yet refined the value type 15:41:15 ... definition to be more refined than e.g. xs:string. You can view all of the xs:string ones as a 15:41:28 ... "tbd" to plug in the more specific definition. 15:41:48 pal: Okay, I still see the danger of having two metadata definitions that could both be present 15:41:53 ... and have different values. 15:42:21 q+ 15:42:40 glenn: I'm expecting a translation process. It's possible just to reference RP2052 directly, 15:42:54 ... but then we'd define very few values or have to normatively reference downstream specs, 15:43:17 ... which I've commented on before. We could argue that RP2052 is not downstream from TTML2 15:43:31 ... but from TTML1 so technically that might not be a circular reference, but if it ever changed 15:43:42 ... to refer to TTML2 then I'd still have that concern. 15:43:54 pal: We could resolve that by communicating with SMPTE who could act on that. There's 15:44:07 ... another possibility, which is simply to do nothing, and leave those metadata items in SMPTE 15:44:15 ... and non-normatively point the reader at them. 15:44:34 glenn: Yes, that's an option, or we could define something that points at the SMPTE document 15:44:39 ... to get the value definition. 15:44:46 ... (with a normative reference) 15:45:23 ... Other than the circular reference problem I don't see any problem with that. 15:45:27 q+ 15:45:42 ... I also see a value in enumerating the values here, as a single point of reference. 15:45:58 ack atai 15:46:17 atai: I agree with pal's argument - I would favour a solution where the TTWG, SMPTE and EBU 15:46:33 ... find a way to coordinate their metadata efforts to create an interoperable solution without 15:46:48 ... conflicting definitions or the possibility of confusing duplications. 15:47:15 atai: On validation mechanisms, not everything can be validated in Schema 1.0 but specific 15:47:31 ... constraints like the existing of metadata elements could be validated with Schema 1.0 and 15:47:44 ... that would not be the case with the proposed solution. 15:47:48 ack mike 15:48:10 mike: It's important that even if there's a general way of adding metadata we are clear how to 15:48:36 ... replicate what's in 2052-10. There may be a transitory period where there could be some 15:48:57 ... confusion, until the responding organisations update their specifications to match. 15:49:36 s/to match/to reference the TTML work as needed. 15:50:07 s/TTML work/TTML2 work 15:50:31 glenn: There's a different point about bringing things into TTML and then revising external 15:50:57 ... specs. The reason I brought these into TTML2 was because nigel, mike, andreas and pal had 15:50:58 q+ 15:51:05 q+ 15:51:17 ... followed a bunch of issues saying we should support these metadata. Now it sounds like you're 15:51:22 ... saying you don't want a new mechanism. 15:51:27 q+ 15:51:42 ack pal 15:51:50 ack mike: 15:52:10 mike: For SMPTE and DECE the intent was to sweep the metadata into TTML2 and then reference 15:52:35 ... it, removing the metadata from the SMPTE and DECE. That's the long term plan. The requests 15:53:10 ... from SMPTE and DECE to add these items was for that purpose. Provided the semantics are 15:53:30 ... the same or at least subsettable then that follows the intent. 15:53:31 ack atai 15:53:36 ack mike 15:53:51 atai: I'm not sure about the EBU requests for adding metadata vocabulary - I think we have to 15:54:08 ... go back and look at that. I thought the request was to add the metadata in the ebu namespace. 15:54:21 ... EBU needs to consider this further. Also there have been some comments from John Birch 15:54:40 ... on the list. For me, I would abstain and we can proceed with this and then review by other groups. 15:55:14 glenn: It seems as though all the issues can be surmounted by adding more spec text. 15:55:37 ... If there are semantic discrepancies then they can be fixed. I'm not hearing any strong objection 15:55:54 q+ 15:55:57 ... to moving forward with that in the FPWD. I propose closing these issues en masse and then 15:56:05 ... reviewing post FPWD. 15:56:09 ack pal 15:56:18 nigel: I was going to make that proposal myself. 15:56:34 pal: I have a problem - the FPWD doesn't need to be perfect, but the definitions should at least 15:56:49 ... be a superset of the SMPTE ones - that needs to be fixed before the FPWD. That doesn't 15:56:52 ... sound like a lot of work. 15:57:01 glenn: Please tell me what's broken specifically. 15:57:20 pal: RP2052-10 section 5.6 has a specific definition of a caption service - that doesn't exist 15:57:21 ... in TTML2. 15:58:13 glenn: There's an Editorial note to further specify the details of the named items. 15:59:52 nigel: There's clearly some editorial work to be done as described by Glenn earlier, as well 16:00:00 ... as the editorial points on each metadata items. 16:00:22 glenn: This is a blocker as raised by pal. If we insist on this then it will push the dates back 16:00:39 ... by a month or so. I wanted to get all the main Change Proposals marked as implemented. 16:01:14 ... That doesn't prevent us from dealing with all the issues. 16:02:28 nigel: I was referring the technical changes - I think that the editorial notes are okay for a FPWD 16:02:34 ... as long as it's clear where work is needed. 16:02:53 glenn: I agree with that - or we could remove all the items, but I think that would be a disservice. 16:04:18 -pal 16:04:20 -Andreas 16:04:20 -Mike 16:04:34 -glenn 16:04:36 -tmichel 16:04:47 nigel: Given the state of this discussion and the outstanding technical edits I can't close these 16:04:59 -nigel 16:05:01 SYMM_TTWG()10:00AM has ended 16:05:01 Attendees were nigel, +1.720.897.aaaa, Mike, glenn, pal, tmichel, Andreas 16:05:12 ... issues at this time, so I'll have to hold them open until the new year. 16:05:32 ... Apologies for not getting to the other business. Wishing everyone a good couple of week's 16:05:53 ... break if you're getting one, and see you in January. Thanks for all your work this year. 16:06:08 glenn: "Merry Christmas" (in Hawaiian - too much for the scribe to note down!) 16:06:39 nigel: yes, Happy Christmas too. [adjourns the meeting] 16:06:48 rrsagent, make logs public 16:06:52 rrsagent, generate minutes 16:06:52 I have made the request to generate http://www.w3.org/2014/12/18-tt-minutes.html nigel 16:07:17 nigel: Oh, forgot to add, since we closed Issues 236 and 237 we can close CP20. 16:07:18 rrsagent, generate minutes 16:07:18 I have made the request to generate http://www.w3.org/2014/12/18-tt-minutes.html nigel 16:09:20 s/ack mike:/ 16:10:08 s/zakim ??P11 is me/ 16:10:23 rrsagent, generate minutes 16:10:23 I have made the request to generate http://www.w3.org/2014/12/18-tt-minutes.html nigel 16:11:16 s/referring the technical/referring to the technical 16:12:20 s/"Merry Christmas" (in Hawaiian - too much for the scribe to note down!)/Mele Kalikimaka! - Merry Christmas in Hawaiian! 16:13:22 Regrets: Frans 16:13:49 Present: nigel, glenn, tmichel, Mike, pal, Andreas 16:13:53 rrsagent, generate minutes 16:13:53 I have made the request to generate http://www.w3.org/2014/12/18-tt-minutes.html nigel 16:14:56 ScribeOptions: -final -noEmbedDiagnostics 16:14:57 rrsagent, generate minutes 16:14:57 I have made the request to generate http://www.w3.org/2014/12/18-tt-minutes.html nigel 18:13:08 Zakim has left #tt