Re: Objections to TPAC resolutions on IMSC1.1

I think others also want more time to consider this, so it's likely that we will not spend a long time discussing on Thursday. Things that would be welcome are if anyone has anything new to add, or a change in position.

Thanks,

Nigel


From: David Ronca <dronca@netflix.com<mailto:dronca@netflix.com>>
Date: Wednesday, 29 November 2017 at 04:21
To: Andreas Tai <tai@irt.de<mailto:tai@irt.de>>
Cc: Pierre-Anthony Lemieux <pal@sandflow.com<mailto:pal@sandflow.com>>, Glenn Adams <glenn@skynav.com<mailto:glenn@skynav.com>>, Nigel Megitt <nigel.megitt@bbc.co.uk<mailto:nigel.megitt@bbc.co.uk>>, TTWG <public-tt@w3.org<mailto:public-tt@w3.org>>
Subject: Re: Objections to TPAC resolutions on IMSC1.1

> to discuss them on an email reflector, make only sense until a certain point. I think we passed this point already.
I agree.  I think that we have reached the end of our ability to discuss on the thread.  Netflix is working on a response to the technical concerns that have been raised.  I think that this Thursday will be too soon to have a meaningful conversation on the matter, and I propose that we push the discussion out one week.

In the meantime, we would still like to hear any additional specific technical concerns about our proposal.

Thanks,
David

On Tue, Nov 28, 2017 at 10:44 AM, Andreas Tai <tai@irt.de<mailto:tai@irt.de>> wrote:
Dear all,

It seems obvious to me that we currently do not have any consensus on the discussed issue. I certainly do not agree to take established attributes, copy them to TTML and give them another namespace (e.g. the TTML Styling namespace). I have strong concerns about this procedure (which is one of the core aspects of the Netflix proposals). I commented this in the f2f meeting, in discussions and also in a wide review comment to TTML2.

In general I agree with the comments by Pierre (especially with the points he raised in an Email yesterday evening/morning).

The best way to discuss contentious issues are face 2 face meetings. The second best option are possibly telephone conferences. The third option, to discuss them on an email reflector, make only sense until a certain point. I think we passed this point already. I propose to continue the discussion in the  next call on Thursday (2017-11-30).

Best regards,

Andreas

Von: David Ronca [mailto:dronca@netflix.com<mailto:dronca@netflix.com>]
Gesendet: Dienstag, 28. November 2017 18:15
An: Pierre-Anthony Lemieux <pal@sandflow.com<mailto:pal@sandflow.com>>
Cc: Glenn Adams <glenn@skynav.com<mailto:glenn@skynav.com>>; Nigel Megitt <nigel.megitt@bbc.co.uk<mailto:nigel.megitt@bbc.co.uk>>; TTWG <public-tt@w3.org<mailto:public-tt@w3.org>>
Betreff: Re: Objections to TPAC resolutions on IMSC1.1



On Tue, Nov 28, 2017 at 8:32 AM, Pierre-Anthony Lemieux <pal@sandflow.com<mailto:pal@sandflow.com>> wrote:
Hi David,

> Exactly as proposed in our objection.  Again, apologize if my word choice confused that point.

Do you mean that Neflix' proposal (a) includes moving the definitions
(but not the namespace) as-is, or (b) does not include moving the
definitions (but not the namespace) as-is?
I fear that we may be agreeing to terms that we interpret differently. ttp:activeArea would be restricted so that it is identical to ittp:activeArea. ittp:displayAspectRatio and ttp:displayAspectRatio appear to be equivalent. There are no equivalent options for ebutts:linePadding and ebutts:multiRowAlign. We propose to add them with no change in behavior. A logical copy/paste, if you will.



>> Do you object to bringing the IMSC namespaces in TTML2 and immediately
>> deprecating them?
> Yes.

So the IMSC namespaces would remain in IMSC, where they would be deprecated?
Yes. We think that it is best to manage the IMSC issues in the IMSC spec.

Thanks,

-- Pierre

On Tue, Nov 28, 2017 at 8:29 AM, David Ronca <dronca@netflix.com<mailto:dronca@netflix.com>> wrote:
>
>
> On Tue, Nov 28, 2017 at 6:14 AM, Pierre-Anthony Lemieux <pal@sandflow.com<mailto:pal@sandflow.com>>
> wrote:
>>
>> Hi David,
>>
>> > I meant no modifications in behavior.
>>
>> Do you agree with moving the definitions (but not the namespace) from
>> IMSC1 to TTML2?
>
> Exactly as proposed in our objection.  Again, apologize if my word choice
> confused that point.
>>
>> .
>>
>>
>> > I did not mean bringing the IMSC and EBU-TT namespaces into TTML2.
>>
>> Do you object to bringing the IMSC namespaces in TTML2 and immediately
>> deprecating them?
>
> Yes.
>>
>>
>> Best,
>>
>> -- Pierre
>>
>>
>>
>> On Mon, Nov 27, 2017 at 11:27 PM, David Ronca <dronca@netflix.com<mailto:dronca@netflix.com>> wrote:
>> >> David's exact words were:  "Netflix has proposed adding [IMSC1
>> >> extension definitions] to TTML2 with no modifications."
>> >
>> > I meant no modifications in behavior.  I did not mean bringing the IMSC
>> > and
>> > EBU-TT namespaces into TTML2.  Sorry for the confusion.
>> >
>> > On Mon, Nov 27, 2017 at 9:59 PM, Pierre-Anthony Lemieux
>> > <pal@sandflow.com<mailto:pal@sandflow.com>>
>> > wrote:
>> >>
>> >> Hi Glenn,
>> >>
>> >> David's exact words were:  "Netflix has proposed adding [IMSC1
>> >> extension definitions] to TTML2 with no modifications."
>> >>
>> >> Do you agree with this proposal?
>> >>
>> >> Best,
>> >>
>> >> -- Pierre
>> >>
>> >> On Mon, Nov 27, 2017 at 9:56 PM, Glenn Adams <glenn@skynav.com<mailto:glenn@skynav.com>> wrote:
>> >> > I support the position laid out in Cyril's email, namely, TTML2 gets
>> >> > (in
>> >> > existing TTML namespaces)
>> >> >
>> >> > ttp:activeArea
>> >> > ttp:displayAspectRatio
>> >> > tts:fillLineGap
>> >> > tts:forcedDisplay
>> >> > tts:linePadding
>> >> > tts:multi[Row?]Align
>> >> >
>> >> > We ensure semantics are equivalent.
>> >> >
>> >> > I write tts:multi[Row?]Align because I would prefer tts:multiAlign
>> >> > since
>> >> > the
>> >> > term "Row" is semantically inaccurate; however, I would be willing to
>> >> > concede this point if others insist.
>> >> >
>> >> > Note that, as Cyril has outlined, there are syntactic modifications,
>> >> > so
>> >> > you
>> >> > should probably stop repeating the mantra "no modifications".
>> >> >
>> >> >
>> >> > On Mon, Nov 27, 2017 at 10:17 PM, Pierre-Anthony Lemieux
>> >> > <pal@sandflow.com<mailto:pal@sandflow.com>>
>> >> > wrote:
>> >> >>
>> >> >> Hi Glenn,
>> >> >>
>> >> >> > > Netflix has proposed adding [IMSC1 extension definitions] to
>> >> >> > > TTML2
>> >> >> > > with no modifications
>> >> >>
>> >> >> Do you remain opposed to this approach?
>> >> >>
>> >> >> Best,
>> >> >>
>> >> >> -- Pierre
>> >> >>
>> >> >> On Mon, Nov 27, 2017 at 6:04 PM, David Ronca <dronca@netflix.com<mailto:dronca@netflix.com>>
>> >> >> wrote:
>> >> >> >
>> >> >> >
>> >> >> > On Mon, Nov 27, 2017 at 3:34 PM, Pierre-Anthony Lemieux
>> >> >> > <pal@sandflow.com<mailto:pal@sandflow.com>>
>> >> >> > wrote:
>> >> >> >>
>> >> >> >> Hi David,
>> >> >> >>
>> >> >> >> Thanks for sharing your thoughts.
>> >> >> >>
>> >> >> >> > Netflix has proposed adding them to TTML2 with no modifications
>> >> >> >>
>> >> >> >> At least participant indicated he would strongly object to this
>> >> >> >> approach during the F2F.
>> >> >> >
>> >> >> > Then we need to get the objections and specific concerns on the
>> >> >> > table
>> >> >> > so
>> >> >> > we
>> >> >> > can have a discussion towards resolution.
>> >> >> >>
>> >> >> >>
>> >> >> >> > This is exactly what we have proposed.
>> >> >> >>
>> >> >> >> In the case of itts:forcedDisplay, the changes proposed by
>> >> >> >> Netflix
>> >> >> >> are
>> >> >> >> drastic in syntax.
>> >> >> >
>> >> >> >
>> >> >> > Setting aside itts:forcedDisplay for the moment, what about
>> >> >> > ittp:ActiveArea,
>> >> >> > ittp:aspectRatio, itts:fillLineGap, and ebutts:multiRowAlign?
>> >> >> > These
>> >> >> > are
>> >> >> > not
>> >> >> > significant technical issues, assuming that TTML2 is updated to
>> >> >> > support
>> >> >> > the
>> >> >> > equivalents.
>> >> >> >
>> >> >> >>
>> >> >> >> > We believe that it is better to define the equivalent
>> >> >> >> > tts:multiRowAlign
>> >> >> >> > in TTML2 rather than reference the EBU spec.
>> >> >> >>
>> >> >> >> Can you expand on why Netflix believes it is better? This may
>> >> >> >> help
>> >> >> >> folks change their position.
>> >> >> >
>> >> >> > Because we will have a single upper spec, TTML2, for which we
>> >> >> > profile
>> >> >> > down
>> >> >> > to a manageable subset for IMSC1.1.  That is a clean model.
>> >> >> > Referring
>> >> >> > to
>> >> >> > EBU-TT for a single feature seems unnecessary.
>> >> >> >>
>> >> >> >>
>> >> >> >> Best,
>> >> >> >>
>> >> >> >> -- Pierre
>> >> >> >>
>> >> >> >> On Mon, Nov 27, 2017 at 3:24 PM, David Ronca <dronca@netflix.com<mailto:dronca@netflix.com>>
>> >> >> >> wrote:
>> >> >> >> > Andreas Tai wrote:
>> >> >> >> >> We found resolutions in the f2f meeting on 2017-11-09 and
>> >> >> >> >> 2017-11-10
>> >> >> >> >> based
>> >> >> >> >> on the consensus principle. These resolutions represent
>> >> >> >> >> already a compromise. With the formal objections we are now
>> >> >> >> >> back
>> >> >> >> >> to
>> >> >> >> >> zero
>> >> >> >> >> and need now come again to resolution by the
>> >> >> >> >> consensus principle in our next meetings.
>> >> >> >> >
>> >> >> >> > The F2F established an IMSC1 baseline; a reference point for
>> >> >> >> > the
>> >> >> >> > next
>> >> >> >> > round
>> >> >> >> > of discussion.  We have moved that forward with our objections,
>> >> >> >> > that
>> >> >> >> > were
>> >> >> >> > accompanied with specific recommendations for the spec.  We are
>> >> >> >> > not
>> >> >> >> > back
>> >> >> >> > to
>> >> >> >> > zero.  We now have a very specific set of issues and proposals
>> >> >> >> > that
>> >> >> >> > can
>> >> >> >> > be
>> >> >> >> > discussed.  If we can work through our concerns, then we will
>> >> >> >> > have
>> >> >> >> > a
>> >> >> >> > strong
>> >> >> >> > consensus.
>> >> >> >> >
>> >> >> >> > Pierre wrote:
>> >> >> >> >> for any IMSC 1.0.1 extension adopted by TTML2, semantics and
>> >> >> >> >> syntax
>> >> >> >> >> should be modified as little as possible to avoid additional
>> >> >> >> >> testing,
>> >> >> >> >> training and unintended divergence
>> >> >> >> >
>> >> >> >> > This is exactly what we have proposed.  For the 4 IMSC features
>> >> >> >> > that
>> >> >> >> > are
>> >> >> >> > not
>> >> >> >> > currently covered by TTML2, Netflix has proposed adding them to
>> >> >> >> > TTML2
>> >> >> >> > with
>> >> >> >> > no modifications, and we have also volunteered to take on this
>> >> >> >> > work.
>> >> >> >> >
>> >> >> >> >> working with EBU to integrate features such as
>> >> >> >> >> ebutts:multiRowAlign
>> >> >> >> >> in TTML2 is an opportunity to coordinate with an important
>> >> >> >> >> adopter
>> >> >> >> >> of
>> >> >> >> >> TTML, and reduce the potential for divergence.
>> >> >> >> >
>> >> >> >> > We believe that it is better to define the equivalent
>> >> >> >> > tts:multiRowAlign
>> >> >> >> > in
>> >> >> >> > TTML2 rather than reference the EBU spec.
>> >> >> >> >
>> >> >> >> >> organizations that have recently adopted IMSC1 might lose
>> >> >> >> >> confidence
>> >> >> >> >> with the TTWG process if IMSC 1.1 deprecates all IMSC1
>> >> >> >> >> extensions
>> >> >> >> >> and
>> >> >> >> >> replaces them with substantially different alternatives
>> >> >> >> > Netflix is such an organization, having recently adopted IMSC1.
>> >> >> >> > I
>> >> >> >> > also
>> >> >> >> > expect that we currently have the largest IMSC1 asset library.
>> >> >> >> > We
>> >> >> >> > don't
>> >> >> >> > take these changes lightly, but do so looking forward.  The
>> >> >> >> > real
>> >> >> >> > implication
>> >> >> >> > of deprecated features is that at some point in the future, in
>> >> >> >> > some
>> >> >> >> > future
>> >> >> >> > version of the spec, the deprecated features will no longer be
>> >> >> >> > supported
>> >> >> >> > in
>> >> >> >> > that version of the spec.  IMSC1.01 processors will exist for
>> >> >> >> > as
>> >> >> >> > long
>> >> >> >> > as
>> >> >> >> > there is a business case for them, and the translation from
>> >> >> >> > IMSC1
>> >> >> >> > to
>> >> >> >> > an
>> >> >> >> > IMSC
>> >> >> >> > 1.1 that is fully a TTML2 subset is trivial.  Lastly, feature
>> >> >> >> > deprecation is
>> >> >> >> > a normal part of technology development, and certainly not new
>> >> >> >> > to
>> >> >> >> > W3C.
>> >> >> >> >
>> >> >> >> > On Mon, Nov 27, 2017 at 11:09 AM, Glenn Adams
>> >> >> >> > <glenn@skynav.com<mailto:glenn@skynav.com>>
>> >> >> >> > wrote:
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >> On Mon, Nov 27, 2017 at 11:59 AM, Pierre-Anthony Lemieux
>> >> >> >> >> <pal@sandflow.com<mailto:pal@sandflow.com>> wrote:
>> >> >> >> >>>
>> >> >> >> >>> Hi all,
>> >> >> >> >>>
>> >> >> >> >>> >> - IMSC1 has been adopted and deployed for interchange
>> >> >> >> >>> >> between
>> >> >> >> >>> >> multiple
>> >> >> >> >>> >> parties, whereas TTML2 has not
>> >> >> >> >>> > False.
>> >> >> >> >>>
>> >> >> >> >>> IMSC1 is a REC, which is referenced by multiple
>> >> >> >> >>> specifications,
>> >> >> >> >>> including ISO/IEC 23000-19, SMPTE ST 2067-2, ATSC A/343, and
>> >> >> >> >>> DVB
>> >> >> >> >>> A174.
>> >> >> >> >>>
>> >> >> >> >>> IMSC 1.0.1 is a Candidate Recommendation.
>> >> >> >> >>>
>> >> >> >> >>> TTML2 is a Working Draft.
>> >> >> >> >>>
>> >> >> >> >>> > But this has been the plan all along, so such organizations
>> >> >> >> >>> > are
>> >> >> >> >>> > either
>> >> >> >> >>> > misinformed or not following the work of the TTWG.
>> >> >> >> >>>
>> >> >> >> >>> For TTML2 to be successful, TTWG needs to satisfy user needs,
>> >> >> >> >>> not
>> >> >> >> >>> its
>> >> >> >> >>> parochial interests.
>> >> >> >> >>>
>> >> >> >> >>> > Any resolution is subject to a period of at least two weeks
>> >> >> >> >>> > to
>> >> >> >> >>> > obtain
>> >> >> >> >>> > confirmation from member organizations.
>> >> >> >> >>>
>> >> >> >> >>> I am not disputing the right for members to object to a
>> >> >> >> >>> resolution.
>> >> >> >> >>> I
>> >> >> >> >>> am disputing the assertion that "I cannot recall any formal
>> >> >> >> >>> objection
>> >> >> >> >>> to the synonym/alias proposal requested by Netflix". This
>> >> >> >> >>> assertion
>> >> >> >> >>> cannot be true since there was no opportunity for formal
>> >> >> >> >>> objection
>> >> >> >> >>> at
>> >> >> >> >>> TPAC since there was consensus on the resolution.
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >> I do not agree. There was not a consensus, since we explicitly
>> >> >> >> >> noted
>> >> >> >> >> at
>> >> >> >> >> the time that an opportunity must be given members to consider
>> >> >> >> >> the
>> >> >> >> >> matter
>> >> >> >> >> (and that they had 2 weeks to object).
>> >> >> >> >>
>> >> >> >> >> A consensus does not exist.
>> >> >> >> >>
>> >> >> >> >>>
>> >> >> >> >>>
>> >> >> >> >>> Best,
>> >> >> >> >>>
>> >> >> >> >>> -- Pierre
>> >> >> >> >>>
>> >> >> >> >>> On Mon, Nov 27, 2017 at 10:45 AM, Glenn Adams
>> >> >> >> >>> <glenn@skynav.com<mailto:glenn@skynav.com>>
>> >> >> >> >>> wrote:
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > On Mon, Nov 27, 2017 at 11:03 AM, Pierre-Anthony Lemieux
>> >> >> >> >>> > <pal@sandflow.com<mailto:pal@sandflow.com>>
>> >> >> >> >>> > wrote:
>> >> >> >> >>> >>
>> >> >> >> >>> >> Hi Nigel et al.,
>> >> >> >> >>> >>
>> >> >> >> >>> >> I do not believe it is possible to fully capture the
>> >> >> >> >>> >> interactive
>> >> >> >> >>> >> and
>> >> >> >> >>> >> in-person discussions that led to the consensus resolution
>> >> >> >> >>> >> adopted
>> >> >> >> >>> >> at
>> >> >> >> >>> >> TPAC. Nevertheless, based on my notes, below is additional
>> >> >> >> >>> >> information
>> >> >> >> >>> >> that was shared by at least one member (not necessarily
>> >> >> >> >>> >> me)
>> >> >> >> >>> >> during
>> >> >> >> >>> >> these discussions:
>> >> >> >> >>> >>
>> >> >> >> >>> >> - for any IMSC 1.0.1 extension adopted by TTML2, semantics
>> >> >> >> >>> >> and
>> >> >> >> >>> >> syntax
>> >> >> >> >>> >> should be modified as little as possible to avoid
>> >> >> >> >>> >> additional
>> >> >> >> >>> >> testing,
>> >> >> >> >>> >> training and unintended divergence
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > We are not considering the adoption of non-TTML features in
>> >> >> >> >>> > TTML2.
>> >> >> >> >>> > We
>> >> >> >> >>> > are
>> >> >> >> >>> > defining core functionality that we have been discussing
>> >> >> >> >>> > for
>> >> >> >> >>> > some
>> >> >> >> >>> > time
>> >> >> >> >>> > now,
>> >> >> >> >>> > before the creation of either IMSC1 or IMSC1.0.1.
>> >> >> >> >>> > Nevertheless,
>> >> >> >> >>> > there
>> >> >> >> >>> > is a
>> >> >> >> >>> > general agreement that common features should have similar
>> >> >> >> >>> > semantics.
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> - given the objective of aligning TTML and CSS, TTML2 can
>> >> >> >> >>> >> delay
>> >> >> >> >>> >> adoption of features in its namespace for which there is
>> >> >> >> >>> >> no
>> >> >> >> >>> >> CSS
>> >> >> >> >>> >> equivalent but for which industry extensions exist, e.g.
>> >> >> >> >>> >> ebutts:linePadding,
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > Given that such an addition to CSS would require years to
>> >> >> >> >>> > obtain
>> >> >> >> >>> > in
>> >> >> >> >>> > a
>> >> >> >> >>> > REC,
>> >> >> >> >>> > it is entirely impractical to use this rationale with TTML2
>> >> >> >> >>> > (and
>> >> >> >> >>> > probably
>> >> >> >> >>> > TTML3).
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> - organizations that have recently adopted IMSC1 might
>> >> >> >> >>> >> lose
>> >> >> >> >>> >> confidence
>> >> >> >> >>> >> with the TTWG process if IMSC 1.1 deprecates all IMSC1
>> >> >> >> >>> >> extensions
>> >> >> >> >>> >> and
>> >> >> >> >>> >> replaces them with substantially different alternatives
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > But this has been the plan all along, so such organizations
>> >> >> >> >>> > are
>> >> >> >> >>> > either
>> >> >> >> >>> > misinformed or not following the work of the TTWG.
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> - IMSC1 has been adopted and deployed for interchange
>> >> >> >> >>> >> between
>> >> >> >> >>> >> multiple
>> >> >> >> >>> >> parties, whereas TTML2 has not
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > False.
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> - working with EBU to integrate features such as
>> >> >> >> >>> >> ebutts:multiRowAlign
>> >> >> >> >>> >> in TTML2 is an opportunity to coordinate with an important
>> >> >> >> >>> >> adopter
>> >> >> >> >>> >> of
>> >> >> >> >>> >> TTML, and reduce the potential for divergence.
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > Adopting non-TTML vocabulary is contrary to the original
>> >> >> >> >>> > requirements
>> >> >> >> >>> > documented by TTAF1 for use in TTML.
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> > Given that I cannot recall any formal objection to the
>> >> >> >> >>> >> > synonym/alias
>> >> >> >> >>> >> > proposal requested by Netflix,
>> >> >> >> >>> >>
>> >> >> >> >>> >> There was no opportunity to raise formal objections during
>> >> >> >> >>> >> the
>> >> >> >> >>> >> TPAC
>> >> >> >> >>> >> meeting since the resolution was adopted by consensus.
>> >> >> >> >>> >
>> >> >> >> >>> >
>> >> >> >> >>> > Any resolution is subject to a period of at least two weeks
>> >> >> >> >>> > to
>> >> >> >> >>> > obtain
>> >> >> >> >>> > confirmation from member organizations.
>> >> >> >> >>> >
>> >> >> >> >>> >>
>> >> >> >> >>> >>
>> >> >> >> >>> >> Best,
>> >> >> >> >>> >>
>> >> >> >> >>> >> -- Pierre
>> >> >> >> >>> >>
>> >> >> >> >>> >> On Fri, Nov 24, 2017 at 9:13 AM, Nigel Megitt
>> >> >> >> >>> >> <nigel.megitt@bbc.co.uk<mailto:nigel.megitt@bbc.co.uk>>
>> >> >> >> >>> >> wrote:
>> >> >> >> >>> >> > All,
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > This is a situation in which we do not currently seem to
>> >> >> >> >>> >> > have
>> >> >> >> >>> >> > consensus.
>> >> >> >> >>> >> > It
>> >> >> >> >>> >> > appears that two camps exist, with mutually incompatible
>> >> >> >> >>> >> > visions
>> >> >> >> >>> >> > for
>> >> >> >> >>> >> > how
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > IMSC 1.1 and TTML2 specifications should incorporate
>> >> >> >> >>> >> > some
>> >> >> >> >>> >> > features.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Be reminded that W3C consensus means we have to find a
>> >> >> >> >>> >> > solution
>> >> >> >> >>> >> > that
>> >> >> >> >>> >> > everyone can accept, even though it might not be the one
>> >> >> >> >>> >> > that
>> >> >> >> >>> >> > everyone
>> >> >> >> >>> >> > thinks is the best alternative.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > To summarise the technical issue as I understand it:
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > * IMSC 1.0.1 includes extensions not in TTML1, defined
>> >> >> >> >>> >> > using
>> >> >> >> >>> >> > syntax
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > namespaces not defined by TTML1
>> >> >> >> >>> >> > * We want to support the requirements met by those
>> >> >> >> >>> >> > extensions
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > IMSC
>> >> >> >> >>> >> > 1.1
>> >> >> >> >>> >> > * We want to support the requirements met by those
>> >> >> >> >>> >> > extensions
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > TTML2
>> >> >> >> >>> >> > * We want IMSC 1.1 to be a subset of TTML2 – there are
>> >> >> >> >>> >> > varying
>> >> >> >> >>> >> > degrees
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > strength about this amongst the group members, i.e. some
>> >> >> >> >>> >> > want
>> >> >> >> >>> >> > all
>> >> >> >> >>> >> > non-TTML2
>> >> >> >> >>> >> > features to be deprecated, others are happy to continue
>> >> >> >> >>> >> > with
>> >> >> >> >>> >> > non-deprecated
>> >> >> >> >>> >> > extensions.
>> >> >> >> >>> >> > * It is important to some (maybe all) members that IMSC
>> >> >> >> >>> >> > 1.1
>> >> >> >> >>> >> > processors
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > able to process IMSC 1.0.1 documents
>> >> >> >> >>> >> > * We discussed but rejected creating an IMSC 2 that is a
>> >> >> >> >>> >> > pure
>> >> >> >> >>> >> > subset
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > TTML2 and does not natively support IMSC 1.0.1
>> >> >> >> >>> >> > * It is important to some (but not all) members that
>> >> >> >> >>> >> > TTML2
>> >> >> >> >>> >> > defines
>> >> >> >> >>> >> > all
>> >> >> >> >>> >> > features in its own namespace
>> >> >> >> >>> >> > * The idea of adopting extensions into TTML2 and making
>> >> >> >> >>> >> > them
>> >> >> >> >>> >> > features
>> >> >> >> >>> >> > with
>> >> >> >> >>> >> > no change to their existing namespace was discussed but
>> >> >> >> >>> >> > not
>> >> >> >> >>> >> > adopted.
>> >> >> >> >>> >> > There
>> >> >> >> >>> >> > was a formal objection on the grounds that all TTML
>> >> >> >> >>> >> > features
>> >> >> >> >>> >> > must
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > defined
>> >> >> >> >>> >> > in the TTML namespace. There was also a process point
>> >> >> >> >>> >> > that
>> >> >> >> >>> >> > we
>> >> >> >> >>> >> > would
>> >> >> >> >>> >> > need
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > seek permission from EBU for inclusion of EBU namespace
>> >> >> >> >>> >> > extensions.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > During the TPAC 2017 face to face meeting (minutes) we
>> >> >> >> >>> >> > resolved
>> >> >> >> >>> >> > one
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > two
>> >> >> >> >>> >> > approaches for each feature:
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > 1. In TTML2: include a new feature in a TTML namespace.
>> >> >> >> >>> >> > In
>> >> >> >> >>> >> > IMSC
>> >> >> >> >>> >> > 1.1:
>> >> >> >> >>> >> > deprecate the IMSC 1.0.1 extension AND include the TTML2
>> >> >> >> >>> >> > feature
>> >> >> >> >>> >> > AND
>> >> >> >> >>> >> > provide
>> >> >> >> >>> >> > a mapping from the deprecated extension to the new
>> >> >> >> >>> >> > feature.
>> >> >> >> >>> >> > 2. In TTML2: do not include a new feature. In IMSC 1.1:
>> >> >> >> >>> >> > include
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > IMSC
>> >> >> >> >>> >> > 1.0.1 extension.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Netflix has objected to some of those resolutions within
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > WG's
>> >> >> >> >>> >> > review
>> >> >> >> >>> >> > period defined under the Decision Policy in the Charter.
>> >> >> >> >>> >> > I
>> >> >> >> >>> >> > have
>> >> >> >> >>> >> > received
>> >> >> >> >>> >> > no
>> >> >> >> >>> >> > other objections within that period (which expires at
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > end
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > working
>> >> >> >> >>> >> > day today, California time). I have updated and where
>> >> >> >> >>> >> > necessary
>> >> >> >> >>> >> > reopened
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > relevant GitHub issues indicating the objection.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > * The idea of synonyms or aliases was raised
>> >> >> >> >>> >> > (disclosure:
>> >> >> >> >>> >> > by
>> >> >> >> >>> >> > me),
>> >> >> >> >>> >> > discussed
>> >> >> >> >>> >> > but not adopted, i.e. TTML namespace syntax for features
>> >> >> >> >>> >> > where
>> >> >> >> >>> >> > each
>> >> >> >> >>> >> > feature
>> >> >> >> >>> >> > is a functional equivalent or superset of an IMSC 1.0.1
>> >> >> >> >>> >> > extension,
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > both
>> >> >> >> >>> >> > may be supported in IMSC 1.1 with a mapping to the
>> >> >> >> >>> >> > canonical
>> >> >> >> >>> >> > TTML2
>> >> >> >> >>> >> > equivalent. The synonym may additionally be noted
>> >> >> >> >>> >> > informatively
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > TTML2.
>> >> >> >> >>> >> > The key negative point was that it would encourage the
>> >> >> >> >>> >> > use
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > both
>> >> >> >> >>> >> > sets
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > syntax in many documents with no clear end point to the
>> >> >> >> >>> >> > practice
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > no
>> >> >> >> >>> >> > practical benefit. However I cannot recall any formal
>> >> >> >> >>> >> > objection,
>> >> >> >> >>> >> > nor
>> >> >> >> >>> >> > find
>> >> >> >> >>> >> > one in the minutes.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > The Netflix objection essentially requests that this
>> >> >> >> >>> >> > latter
>> >> >> >> >>> >> > model
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > adopted, whilst deprecating the IMSC 1.0.1 extensions.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Given that I cannot recall any formal objection to the
>> >> >> >> >>> >> > synonym/alias
>> >> >> >> >>> >> > proposal requested by Netflix, I'd like to check if we
>> >> >> >> >>> >> > actually
>> >> >> >> >>> >> > have
>> >> >> >> >>> >> > consensus to adopt it already, i.e. if despite it not
>> >> >> >> >>> >> > being
>> >> >> >> >>> >> > everyone's
>> >> >> >> >>> >> > favourite option, it is something that everyone can
>> >> >> >> >>> >> > nevertheless
>> >> >> >> >>> >> > live
>> >> >> >> >>> >> > with.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Does anyone object to any of the Netflix proposals? If
>> >> >> >> >>> >> > so,
>> >> >> >> >>> >> > please
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > specific about the nature of the objection. This will
>> >> >> >> >>> >> > help
>> >> >> >> >>> >> > us
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > construct
>> >> >> >> >>> >> > new proposals.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > This topic will be on the agenda for next week's call
>> >> >> >> >>> >> > (November
>> >> >> >> >>> >> > 30th),
>> >> >> >> >>> >> > but
>> >> >> >> >>> >> > if possible I would like to have a sense of the
>> >> >> >> >>> >> > conclusion
>> >> >> >> >>> >> > or
>> >> >> >> >>> >> > any
>> >> >> >> >>> >> > as
>> >> >> >> >>> >> > yet
>> >> >> >> >>> >> > unraised concerns before the meeting. If anyone would
>> >> >> >> >>> >> > like
>> >> >> >> >>> >> > a
>> >> >> >> >>> >> > call
>> >> >> >> >>> >> > with
>> >> >> >> >>> >> > me or
>> >> >> >> >>> >> > others to discuss this informally ahead of the meeting,
>> >> >> >> >>> >> > I
>> >> >> >> >>> >> > am
>> >> >> >> >>> >> > happy
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > support that, and can be available on Monday 1600-1700
>> >> >> >> >>> >> > UK
>> >> >> >> >>> >> > time,
>> >> >> >> >>> >> > Tuesday
>> >> >> >> >>> >> > 1630-1730 UK time or Wednesday 1500-1730 UK time.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Nigel
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > From: Cyril Concolato <cconcolato@netflix.com<mailto:cconcolato@netflix.com>>
>> >> >> >> >>> >> > Date: Wednesday, 15 November 2017 at 18:55
>> >> >> >> >>> >> > To: TTWG <public-tt@w3.org<mailto:public-tt@w3.org>>
>> >> >> >> >>> >> > Subject: Objections to TPAC resolutions on IMSC1.1
>> >> >> >> >>> >> > Resent-From: <public-tt@w3.org<mailto:public-tt@w3.org>>
>> >> >> >> >>> >> > Resent-Date: Wednesday, 15 November 2017 at 18:56
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Dear TTWG experts,
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Following TPAC, Netflix would like to inform the group
>> >> >> >> >>> >> > that
>> >> >> >> >>> >> > it
>> >> >> >> >>> >> > is
>> >> >> >> >>> >> > not
>> >> >> >> >>> >> > satisfied with some of the resolutions regarding IMSC1.1
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > objects
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > them. Netflix thinks that two important goals must be
>> >> >> >> >>> >> > satisfied
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > defining
>> >> >> >> >>> >> > TTML2 and IMSC1.1:
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - IMSC1.1 must be a strict-subset of TTML2, aside from
>> >> >> >> >>> >> > deprecated
>> >> >> >> >>> >> > features.
>> >> >> >> >>> >> > We believe it is bad practice for W3C to define two
>> >> >> >> >>> >> > TTML-based
>> >> >> >> >>> >> > standards, at
>> >> >> >> >>> >> > the same time, which are not compatible with each other.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - TTML2 must limit its normative references to Web
>> >> >> >> >>> >> > Platform
>> >> >> >> >>> >> > standards.
>> >> >> >> >>> >> > We
>> >> >> >> >>> >> > believe it is bad practice to have to compile multiple
>> >> >> >> >>> >> > sources
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > information outside of the Web Platform to implement the
>> >> >> >> >>> >> > standard.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Netflix asks for the following actions:
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > a) Marking ittp:activeArea deprecated in IMSC1.1, using
>> >> >> >> >>> >> > a
>> >> >> >> >>> >> > reference
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > IMSC1.0.1 and no definition in IMSC1.1, in favor of
>> >> >> >> >>> >> > ttp:activeArea,
>> >> >> >> >>> >> > restricted to using two-component values such that
>> >> >> >> >>> >> > ttp:activeArea
>> >> >> >> >>> >> > can be
>> >> >> >> >>> >> > used to do no more than IMSC1.0.1 ittp:activeArea.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > b) Marking ittp:aspectRatio deprecated in IMSC1.1, using
>> >> >> >> >>> >> > a
>> >> >> >> >>> >> > reference
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > IMSC1.0.1 and no definition in IMSC1.1, in favor of
>> >> >> >> >>> >> > ttp:displayAspectRatio.
>> >> >> >> >>> >> > There does not seem to be a need for restricting
>> >> >> >> >>> >> > ttp:displayAspectRatio.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > c) Marking itts:forcedDisplay deprecated in IMSC1.1,
>> >> >> >> >>> >> > using
>> >> >> >> >>> >> > a
>> >> >> >> >>> >> > reference
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > IMSC1.0.1 and no definition in IMSC1.1, in favor of a
>> >> >> >> >>> >> > combination
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > 'condition' and 'tts:visibility', with the appropriate
>> >> >> >> >>> >> > restrictions
>> >> >> >> >>> >> > on
>> >> >> >> >>> >> > condition such that it remains simple to implement,
>> >> >> >> >>> >> > while
>> >> >> >> >>> >> > at
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > same
>> >> >> >> >>> >> > time
>> >> >> >> >>> >> > offering more flexibility than forcedDisplay.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > d) Adding the definitions of itts:fillLineGap,
>> >> >> >> >>> >> > ebutts:linePadding
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > ebutts:multiRowAlign to TTML2, with no change to the
>> >> >> >> >>> >> > semantics,
>> >> >> >> >>> >> > but
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > TTML namespace; and marking the itts/ebutts version as
>> >> >> >> >>> >> > deprecated
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > IMSC1.1.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > e) IMSC1.1 should indicate that when TTML2 features are
>> >> >> >> >>> >> > used
>> >> >> >> >>> >> > in
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > same
>> >> >> >> >>> >> > document at the same time as their non-TTML2 equivalent
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > deprecated
>> >> >> >> >>> >> > features, the TTML2 features prevail. This insures that
>> >> >> >> >>> >> > future
>> >> >> >> >>> >> > versions
>> >> >> >> >>> >> > of
>> >> >> >> >>> >> > IMSC can effectively remove the features marked as
>> >> >> >> >>> >> > deprecated.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Netflix believes that this approach provides clearly
>> >> >> >> >>> >> > designed,
>> >> >> >> >>> >> > forward
>> >> >> >> >>> >> > looking standards, reducing the complexity of the TTML
>> >> >> >> >>> >> > ecosystem.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Netflix is aware that this requires an effort of the
>> >> >> >> >>> >> > TTML
>> >> >> >> >>> >> > community
>> >> >> >> >>> >> > as
>> >> >> >> >>> >> > follows:
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - IMSC1.0.1 renderers do not need to be updated, unless
>> >> >> >> >>> >> > they
>> >> >> >> >>> >> > need
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > support
>> >> >> >> >>> >> > Japanese features. The changes required by the proposed
>> >> >> >> >>> >> > dual
>> >> >> >> >>> >> > syntax
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > deprecation model are minor compared to them, as they
>> >> >> >> >>> >> > can
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > implemented
>> >> >> >> >>> >> > using aliases or simple transforms.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - Authoring tools already supporting IMSC1.0.1 do not
>> >> >> >> >>> >> > need
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > migrate to
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > TTML2 syntax, as renderers are required to support both.
>> >> >> >> >>> >> > They
>> >> >> >> >>> >> > only
>> >> >> >> >>> >> > need
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > be updated to support Japanese features. They would need
>> >> >> >> >>> >> > to
>> >> >> >> >>> >> > be
>> >> >> >> >>> >> > updated
>> >> >> >> >>> >> > when
>> >> >> >> >>> >> > the deprecated features are removed in a future version.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - Specs need to be updated. Netflix is willing to update
>> >> >> >> >>> >> > the
>> >> >> >> >>> >> > TTML2
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > IMSC1.1 specs as proposed above.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > - Test suites need to be updated. For each of the
>> >> >> >> >>> >> > features
>> >> >> >> >>> >> > above,
>> >> >> >> >>> >> > 2
>> >> >> >> >>> >> > additional tests need to be provided: one with the TTML2
>> >> >> >> >>> >> > flavor
>> >> >> >> >>> >> > and
>> >> >> >> >>> >> > without
>> >> >> >> >>> >> > the IMSC1.0.1 flavor; and one with both (testing the
>> >> >> >> >>> >> > override
>> >> >> >> >>> >> > model).
>> >> >> >> >>> >> > Netflix is willing to contribute these tests.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > We suggest adding these points to the next meeting's
>> >> >> >> >>> >> > agenda.
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Best regards,
>> >> >> >> >>> >> >
>> >> >> >> >>> >> > Cyril
>> >> >> >> >>> >> >
>> >> >> >> >>> >> >
>> >> >> >> >>> >>
>> >> >> >> >>> >
>> >> >> >> >>
>> >> >> >> >>
>> >> >> >> >
>> >> >> >
>> >> >> >
>> >> >
>> >> >
>> >
>> >
>
>