APA WG comment: Author proposes, user disposes

[michael-n-cooper]

There is a general issue with the way that an author specifies layout characteristics of captions and subtitles, such as font size, font family, line height, background and positioning. It should be made clear that authors can and should define the viewport and text characteristics, but these definitions may be overridden by the user by setting up their user agent to better meet their particular needs as users (cf. MAUR, 3.7 Requirements on the use of the viewport). For example, a user with vision impairment who also requires caption support may want to have all captions displayed in the lower third of the screen with a large font, disregarding the definition of various viewports and font types defined by the author. We recommend adding a note to the spec to advise authors that the final rendition of their document may not follow their specified styling and positioning, but follow user-defined styling and positioning instead.

[css-meeting-bot]

The Timed Text Working Group just discussed APA WG comment: Author proposes, user disposes, and agreed to the following:

• SUMMARY: Discussed and editor to add text to D.2 to express this concept

The full IRC log of that discussion

<cyril_> Topic: APA WG comment: Author proposes, user disposes
<cyril_> github: https://github.com//issues/523
<cyril_> nigel: we have MAUR in D.2
<cyril_> ... this particular issue recommends adding a note to the spec
<cyril_> pal: I can see what it means but the wording does not seem useful
<cyril_> ... as a general idea, saying that the final rendering depends on user settings, local regulation ...
<cyril_> ... we could say that, if don't say it already somewhere
<cyril_> nigel: I do have a bit of a fundamental problem
<cyril_> ... authors specifying layout is not an issue
<cyril_> ... it's a positive point
<cyril_> ... the authors know what's in the video when the subs will be presented
<cyril_> ... I get that sometimes people want to override that
<gkatsev> q+
<cyril_> gkatsev: I agree with you Nigel but on the other hand, it would be useful for author that it's going to happen
<cyril_> ... for example for the CVAA in the US and the font-size change
<cyril_> ... the captions can become too big and missing
<cyril_> ack gkatsev
<cyril_> pal: we've had this discussion many times before
<cyril_> ... there are different regulations in different places
<cyril_> ... I don't think we can summarize it in one sentenc
<cyril_> ... I don't know how to make a sentence that is productive
<cyril_> ... just saying it might not be rendered as the author intended is not sufficient
<cyril_> q+
<cyril_> nigel: we don't provide in IMSC any tools that the author can sensibly take advantage of
<cyril_> ... the closest is overflow and wrap option
<cyril_> ... but even then, they are not that useful
<cyril_> ... we could say don't make region as tight as possible
<cyril_> ... there are techniques that you can put for specific cases
<cyril_> ... the second point is that this guidelines is more targeted to implementers of processors rather than authors
<cyril_> ... we might want to get back to them to ask if they meant authors
<cyril_> ... because this specification says in the absence of anything else this is how to render
<cyril_> ... but in practice implementers have to take other things into account
<cyril_> pal: we could reference issue #316
<cyril_> ... the resolution was to add the reference to MAUR
<cyril_> ... my proposed disposition would be in the MAUR section to add a note along the lines of what you just mentioned
<nigel> scribe: nigel
<nigel> cyril: What about adding an example?
<nigel> .. We could say there are plenty of ways for authors to take into account and give
<nigel> .. the example like what Nigel said not to make the region too tight so the text does
<cyril_> cyril_: what about giving an example
<nigel> .. not get clipped.
<nigel> scribe: cyril_
<cyril_> pal: in section D.2
<cyril_> ... we have one sentence
<cyril_> ... we could expand on that
<cyril_> gkatsev: I think maybe it's enough to say that authors should specify styling and positioning and that due to MAUR it may be overriden
<cyril_> pal: I like that, we could say the document specifies a nominal rendering
<cyril_> ... I want to avoid saying 'authors'
<cyril_> gkatsev: the sticking point is that users can modify the rendering (not the accessibility requirements)
<cyril_> nigel: this is the document processing context
<cyril_> ... users may influence the document processing context to modify the actual presentation in order to meet the MAUR guidelines
<cyril_> SUMMARY: Discussed and editor to add text to D.2 to express this concept

[gzimmermann]

I think the note should be clearer to say:

• Under what circumstances can the user influence the presentation of captions? Cf. nigelmegitt's comment on #527.
• The author is strongly recommended (for the purpose of accessibility) to give the user full flexibility in influencing the presentation of captions.

[nigelmegitt]

The author is strongly recommended (for the purpose of accessibility) to give the user full flexibility in influencing the presentation of captions.

@gzimmermann I don't think this suggestion makes sense, or is in any case a good idea, for a couple of reasons:

1. the captions author has no control of the flexibility that implementations offer.
2. generally authors specify the 'standard' presentation of captions, e.g. specifying size, colour of text and background, position, timing etc, in order to make the viewing experience more accessible. This is valuable to many users. The alternative that "full flexibility" seems to suggest is that the least presentation data is provided, leading to a minimal "text and times" only document, which is likely to give a significantly less accessible experience to the majority of users. For example they would not be able to position the captions so they do not obscure important parts of the video.

The way I see it, in this case recommending authors give the user full flexibility would probably not result in any improvement to the accessibility of media with captions.

[css-meeting-bot]

The Timed Text Working Group just discussed APA WG comment: Author proposes, user disposes imsc#523, and agreed to the following:

• SUMMARY: TTWG has not identified any way to address @gzimmermann's second bullet; review of #527 to continue with a view to merging.

The full IRC log of that discussion

<nigel> Topic: APA WG comment: Author proposes, user disposes imsc#523
<nigel> github: https://github.com//issues/523
<nigel> Pierre: There's a PR open but no comment on that.
<nigel> .. I feel the work I put in is being ignored!
<nigel> Nigel: @gzimmermann does reference the pull request #527 so I think he has actually
<nigel> .. noticed it, but added the comment to the issue not the pull request.
<nigel> Pierre: Anyway I agree with your answer Nigel.
<nigel> Nigel: It looks like there is support for my proposal on #527. I see that I haven't re-reviewed
<nigel> .. since you addressed my comment, not sure why.
<nigel> Pierre: Hopefully I did exactly what you proposed.
<nigel> Nigel: Then the 2nd comment needs some thought about what we do.
<nigel> .. I think Pierre agreed, I want to know if there is consensus in the group or another
<nigel> .. proposal that we can be more positive with.
<nigel> Andreas: I think it is impossible to meet the requirement and think of every possible
<nigel> .. user customisation and author in this way. It is not really possible.
<nigel> Nigel: Then are you suggesting not making a change?
<nigel> Andreas: It is hard to see how you can make a change.
<nigel> .. Are you proposing adding a note explaining the limit of how authors can anticipate
<nigel> .. user customisation?
<nigel> Nigel: I'm not proposing that.
<nigel> Gary: Also isn't it the renderer that gives the users the capability of controlling the
<nigel> .. presentation?
<nigel> Nigel: Yes it is.
<nigel> Gary: So the author doesn't really have any control there at all.
<nigel> Nigel: That's my understanding.
<nigel> Gary: Other than trying to make it simpler so there's not a whole bunch of stuff to override,
<nigel> .. but as you mention there's a limit to how far people should be taking that.
<nigel> Nigel: There is an example we talked about before, where the semantic organisation
<nigel> .. of content affects the ability to customise presentation.
<nigel> .. The example we've hit at the BBC is the ability to reduce text size. If each line of text
<nigel> .. is in a separate region then proportionally the lines get spaced further apart as the
<nigel> .. text size is reduced, but if the text is all in the same p, then the lines get closer together
<nigel> .. and the result is much more pleasing. That's just one example. I don't know how to
<nigel> .. write this down in a useful way.
<nigel> Andreas: To meet the requirement you possibly need to agree on a certain pattern on
<nigel> .. how to write documents. To then give recommendations for how to be prepared for
<nigel> .. user customisation at presentation time.
<nigel> Nigel: Possibly a statement we could make is that it is likely to be easier for presentation
<nigel> .. processors to apply customisations if the content is organised semantically.
<nigel> Andreas: Can you explain what you mean?
<nigel> Nigel: Yes, I'm referring to dialogue, say, being all in the same p for the same person,
<nigel> .. rather than broken up and targeted purely at a particular presentation paradigm.
<nigel> Andreas: That's really hard, and unsolved. For example OSes like Android and iOS have
<nigel> .. different systems for presenting text. There's no concept for how this is brought together
<nigel> .. with subtitle and caption formats. It would be good to have the concept there but it
<nigel> .. is not existing yet so for our part, delivering the technical capability to deliver subtitles,
<nigel> .. it is really difficult to give any more advice now.
<nigel> Nigel: Checking in then, is there some action we can take to address the second bullet?
<nigel> Pierre: I don't know what we can write. The user does not need permission from the author.
<nigel> .. I don't know how that is useful for anybody.
<nigel> Nigel: Any objections to us disposing to do nothing in response to the second bullet?
<nigel> Pierre: I certainly don't object to that.
<nigel> Nigel: I hear no objections so I think that's our agreed way forward.
<nigel> SUMMARY: TTWG has not identified any way to address @gzimmermann's second bullet; review of #527 to continue with a view to merging.

[gzimmermann]

I see that #527 is very much related, so we can merge. It is okay to look at this in the broader context of personalization, after release of IMSC 1.2.
@nigelmegitt In general, i agree that it would not be a good solution to discourage authors from providing no or only little data on presentation. What we really need here is a solid personalization concept for the presentation of Timed Text. This concept will cover considerations for authors and for implementors.

[nigelmegitt]

Thank you for that @gzimmermann .

[michael-n-cooper]

APA agrees to defer this to later version.

[michael-n-cooper]

Re-adding a11y-needs-resolution label because of new information about how the horizontal review tracker works, but this is still signed off from APA.