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Re: Proposed extension to HTML5.1 for rollup captions

From: David Singer <singer@apple.com>
Date: Tue, 05 Mar 2013 16:15:28 -0700
Cc: Paul Cotton <Paul.Cotton@microsoft.com>, public-html <public-html@w3.org>
Message-id: <04E6D70C-D668-4B45-8F34-930A9A94C6CE@apple.com>
To: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Hi

yes, we have been taking the time to work on the FCC-mandated features, and get some implementation experience.  These seem to be settling nicely, so once the editor transition is over, indeed an FSA is indicated.

There are people who'd like the work to transition into a WG and get on the REC track, indeed.  To what extent the HTML work should be linked to, or predicated on, TTML or VTT, I am less sure.

My apologies for not noticing the question before, and I hope this helps.

On Mar 5, 2013, at 15:55 , Silvia Pfeiffer <silviapfeiffer1@gmail.com> wrote:

> Hi Paul,
> 
> Sorry about the lack of a reply. The CG is currently working on a transition of editor and preparation for a Final Spec Agreement. It hasn't happened yet. So, indeed we can wait in the HTML WG until that has happened.
> 
> I've cc-ed David Singer who is the chair of the CG in case you need more information.
> 
> Cheers,
> Silvia.
> 
> 
> On Wed, Mar 6, 2013 at 4:10 AM, Paul Cotton <Paul.Cotton@microsoft.com> wrote:
> I have not seen a response to my questions:
> 
>  
> 
> > Has the TextTracks Community Group published a  Final Specification and has the W3C issued a call for participants to sign the Final Specification Agreement [1] for that Final Specification?  Shouldn’t this be done before the material is adopted into the HTML WG?
> 
>  
> 
> If Silvia cannot answer who should I contact?
> 
>  
> 
> /paulc
> 
> HTML WG co-chair
> 
>  
> 
> Paul Cotton, Microsoft Canada
> 
> 17 Eleanor Drive, Ottawa, Ontario K2E 6A3
> 
> Tel: (425) 705-9596 Fax: (425) 936-7329
> 
>  
> 
> From: Paul Cotton 
> Sent: Wednesday, February 20, 2013 3:28 PM
> To: 'Silvia Pfeiffer'
> Cc: public-html
> Subject: RE: Proposed extension to HTML5.1 for rollup captions
> 
>  
> 
> > One proposals was picked and developed further: http://www.w3.org/community/texttracks/wiki/MultiCueBox
> 
>  
> 
> Has the TextTracks Community Group published a  Final Specification and has the W3C issued a call for participants to sign the Final Specification Agreement [1] for that Final Specification?  Shouldn’t this be done before the material is adopted into the HTML WG?
> 
>  
> 
> /paulc
> 
> HTML WG co-chair
> 
>  
> 
> [1] http://www.w3.org/community/about/agreements/
> 
>  
> 
> Paul Cotton, Microsoft Canada
> 
> 17 Eleanor Drive, Ottawa, Ontario K2E 6A3
> 
> Tel: (425) 705-9596 Fax: (425) 936-7329
> 
>  
> 
> From: Silvia Pfeiffer [mailto:silviapfeiffer1@gmail.com] 
> 
> Sent: Wednesday, February 20, 2013 12:57 AM
> To: public-html
> Subject: Proposed extension to HTML5.1 for rollup captions
> 
>  
> 
> Hi all,
> 
> 
> 
> This is a proposal to extend the TextTrack API in HTML with new objects that will enable the display of captions/subtitles as scrolling text, and introduce the ability to move a group of caption/subtitle cues from one location on the video viewport to another. The feature will allow presenting rollup captions from all text track formats that a browser supports, including WebVTT and TTML.
> 
> Specification: https://dvcs.w3.org/hg/text-tracks/raw-file/default/608toVTT/region.html#extension-of-the-html-texttrack-api
> (Only the Appendix is relevant to the HTML WG).
> 
> I'm looking for feedback on this feature here. If there are no objections and sufficient support for these features, I suggest adding them to the HTML5.1 specification.
> 
> 
> The use case:
> ============
> Summary: Video users of diverse nations are used to the use of rollup captions from TV. Deaf users have asked to have all TV content be displayed on the Web in the same format. In the US it is a legal requirement to support rollup captions on all video devices.
> 
> Details:
> The display of captions/subtitles as scrolling text is known as "rollup captions" (e.g. [0]). It is one of three standard display styles for captions on TV [1]. It is often used when material is live captioned and for post-production broadcast programming that only has one speaker. [2]
> 
> Rollup is part of the Consumer Electronics Association specifications of captioning for analog TV (CEA608) and for digital TV (CEA708). It is not only supported on TV but also on DVD through the SCC format [4]. It is used in the US, Canada [5], Australia, and probably other countries. The QuickTime file format supports it (e.g. [6]).
> 
> Rollup captions on all video devices, including devices that display Web content, are a legal requirement in the US, introduced through the Communications and Video Accessibility Act (CVAA) by the Federal Communications Commission (FCC) 79.103 [7].
> 
> 
> The proposal:
> ===========
> Summary: Introduce a TextTrackRegion object that is a video viewport region and can hold multiple TextTrackCues. The properties of TextTrackRegion specify the display location and text scrolling mechanism for the cues it contains. 
> 
> Details:
> In the TextTracks Community Group we have analysed how to introduce rollup captions using WebVTT and the HTML <track> element.
> 
> 11 different proposals were analysed: http://www.w3.org/community/texttracks/wiki/RollupCaptions .
> 
> One proposals was picked and developed further: http://www.w3.org/community/texttracks/wiki/MultiCueBox
> There is a trial implementation in JavaScript for WebVTT: https://github.com/silviapfeiffer/WebVTT-with-regions
> Example rendering: http://html5videoguide.net/test/WebVTT-with-regions/player.html (needs a browser that supports TextTrack, so don't use Firefox).
> 
> An experimental implementation in WebKit is forthcoming: https://bugs.webkit.org/show_bug.cgi?id=109570
> 
> Note: Ian Hickson is not supportive of this feature in WebVTT: https://www.w3.org/Bugs/Public/show_bug.cgi?id=20349 and recommends browsers to implement SCC [4] support instead. However, the objects proposed in this extensions specification would still be required to represent the feature.
> 
> Are there any objections towards introducing these extensions into HTML5.1?
> 
> [0] http://www.slideshare.net/prithviraj_karbar/roll-up-captions-sample
> [1] http://www.dcmp.org/caai/nadh38.pdf
> [2] http://abercap.com/blog/2009/03/17/understanding-the-differences-between-roll-up-captioning-pop-on-captioning-and-subtitling/
> [3] http://www.atsc.org/cms/standards/a53/a_53-Part-3-2009.pdf
> [4] http://www.theneitherworld.com/mcpoodle/SCC_TOOLS/DOCS/SCC_FORMAT.HTML
> [5] http://www.cab-acr.ca/english/social/captioning/captioning.pdf
> [6] http://zeitanker.com/common/movies/PedPoster.mov
> [7] http://www.hallikainen.com/FccRules/2012/79/102/index.php
> 
> Best Regards,
> Silvia.
> 
> 

David Singer
Multimedia and Software Standards, Apple Inc.
Received on Tuesday, 5 March 2013 23:15:58 GMT

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