[EPUB 31][A11Y] Notes for con call held on Oct 5, at 16:00 UTC

8 views
Skip to first unread message

Avneesh Singh

unread,
Oct 6, 2016, 3:31:45 AM10/6/16
to epub-work...@googlegroups.com, Transition to accessible EPUB
Dear Accessibility Group,
 
The notes for conference call held on October 5, 2016, at 16:00 UTC are at 1.
The accessible MS word document is also attached.
 
The accessibility specifications has been approved by the group for going to IP review and membership.
The next call will be after 3 weeks, on October 26, 2016, at 16:00 UTC.
In the meantime we may schedule smaller group calls on ad hoc basis for some specific issues.
 
Thank you very much for the great collaboration for developing 1st accessibility specification for EPUB.
 
1.
 
With regards
Avneesh & Charles
Notes-EPUB 3.1 Accessibility Group Call-2016-10-05.docx

Charles LaPierre

unread,
Dec 22, 2016, 12:52:09 PM12/22/16
to epub-work...@googlegroups.com, Transition to accessible EPUB, Joshua Tallent, Madeleine Rothberg, Geoff Freed
Hello everyone,

During our DIAGRAM's Content Working Group meeting this week the topic of embedding video inside of a EPUB came up with respect to Closed Captioning.
Here is a transcript of what was said, but it boils down to that embedding closed captioning inside a video file is limited to a couple format types which I don’t believe are part of the CORE media times in EPUB and the three types of captioning side load files are also not part of the spec.  Did we forget to include this?

Geoff: yes, these days the file is just a text file that contains captions that have been formatted using one of two or three caption formats: webttt, ttml and srt, all browsers support that. Any browser based tool will rely on the browser to interpret it.

Joshua: What’s the file format?

Geoff: I believe .ttt is the preferred file for webttt is not xml which is why people like it. It’s a simpler construction. The problem with it and its support, it allows for styling of text to look big small, red, green, and etcetera.  Not all browsers support all the styling and placement attributes that are available in the current recommendation. It’s not a final one yet. But if you’re just talking about a very straightforward presentation of captions it should work fine in any system.

 Joshua: This a problem in the EPUB spec or is it only a reading system issue, because it seems to me to be both. If it’s not required of the core media type then support for it isn’t immediately required. If you look at things like font, there are specific fonts listed in the spec and listed as core. So it might make sense to go that way. So when a developer looks at the core specs they know they have to support it to.

Geoff: When you’re looking at it that way, then yes, I agree with you. The actual caption file is a separate entity from everything else.  So the format of the file itself is independent, but has to be supported as a core format so reading systems know what to do with it.  I would recommend that Webttt and ttml be used.

Charles: Why wouldn’t you just embed the closed captioning into the video? Like combine it in there so you would have the video itself that has the closed captioning as part of it.

Geoff: You can do that with a .ftt format. The approach works for QuickTime media, but the reason not too many people use that is because it involves extra rendering of the video. It isn’t as easy to edit. So if you need to make a correction to a caption file that has been created with WebTTT or ttml you just open the file and correct the test. With embedded ones you have to open the movie and then re-render it.

Joshua: you have to have that format specifically mentioned in the core media type. There isn’t a lot of support for anything other than standard n14 formatting.

 Geoff: There isn’t a lot of need to embed caption data and the tools to do it, but these days it’s more flexible to use sidecar format. 

End of Discussion…

In the same vein what about described Audio, is this a CORE media type we need to include as well?  

Or is this all irrelevant because this is a text based format and we don’t need to specifically call out all text based file formats which could appear in an EPUB file?

Thanks
Charles
EOM

Charles LaPierre
Technical Lead, DIAGRAM and Born Accessible
E-mail: char...@benetech.org
Twitter: @CLaPierreA11Y
Skype: charles_lapierre
Phone: 650-600-3301

Siegman, Tzviya - Hoboken

unread,
Dec 22, 2016, 1:10:51 PM12/22/16
to epub-work...@googlegroups.com, Transition to accessible EPUB, Joshua Tallent, Madeleine Rothberg, Geoff Freed

Hi Charles,

 

There’s no change since EPUB 3. We recommend doing the same thing that HTML 5 (now 5.1) recommends. See the video element [1] and the track element [2], specifically the note about accessibility. I am a little confused about why VTT needs to be a core media type.

 

What’s missing from the spec?

 

[1] https://www.w3.org/TR/html51/semantics-embedded-content.html#the-video-element

[2] https://www.w3.org/TR/html51/semantics-embedded-content.html#the-track-element

 

Tzviya Siegman

Information Standards Lead

Wiley

201-748-6884

tsie...@wiley.com

--
You received this message because you are subscribed to the Google Groups "EPUB Working Group" group.
To unsubscribe from this group and stop receiving emails from it, send an email to epub-working-gr...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

Matt Garrish

unread,
Dec 22, 2016, 3:11:00 PM12/22/16
to epub-work...@googlegroups.com, Transition to accessible EPUB, Joshua Tallent, Madeleine Rothberg, Geoff Freed

Also note that files referenced from the track element have been exempt from Core Media Type fallback requirements since 3.0, so I don't see that we need to change anything on the EPUB side.[1] We made the exemption for this reason.

 

[1] http://www.idpf.org/epub/31/spec/epub-contentdocs.html#sec-xhtml-fallbacks

 

Matt

Charles LaPierre

unread,
Dec 22, 2016, 3:15:53 PM12/22/16
to epub-work...@googlegroups.com, Transition to accessible EPUB, Joshua Tallent, Madeleine Rothberg, Geoff Freed
Thanks Matt, that was the piece I was missing.  Whew!  crisis averted.  So really this is just a Reading systems issue on how to handle these side loaded auxiliary captions and also providing the controls to turn on/off captioning when such files exist.


Thanks
EOM

Charles LaPierre
Technical Lead, DIAGRAM and Born Accessible
E-mail: char...@benetech.org
Twitter: @CLaPierreA11Y
Skype: charles_lapierre
Phone: 650-600-3301


Matt Garrish

unread,
Dec 22, 2016, 5:28:51 PM12/22/16
to epub-work...@googlegroups.com, Transition to accessible EPUB, Joshua Tallent, Madeleine Rothberg, Geoff Freed
Reply all
Reply to author
Forward
0 new messages