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[media] re the multitrack activity

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Wed, 16 Feb 2011 08:22:30 +1100
Message-ID: <AANLkTikZfqSbBxRUTsixvRzNaXYk-LEpJPuH9D_OrLiD@mail.gmail.com>
To: HTML Accessibility Task Force <public-html-a11y@w3.org>, Maciej Stachowiak <mjs@apple.com>
Dear media group members,

I have concerns about where we are going with the multitrack activity.
Our multitrack proposal covers the means to mark up and represent in
HTML5 media resources with multiple audio and video tracks, including
sign language and audio descriptions. The proposal has caused big
stirs since posting to the WHATWG and public-html mailing lists. It
seems there is a large overlap with the needs for adaptive HTTP
streaming, which is something being looked at in the W3C Web and TV
activity. There are implications that go much further than just
accessibility and just the W3C, so I am concerned that our deadline of
21st February for putting a change proposal into the HTML Working
Group will not be possible to meet.

Is there any way in which we can deal with this so as to provide us
with time to still include this into the HTML5 spec but after Last

I would also appreciate Maciej's thoughts on this as a HTML WG chair,
which is why I have also sent this to him directly.


---------- Forwarded message ----------
From: Yosuke Funahashi <yfuna@tomo-digi.co.jp>
Date: Wed, Feb 16, 2011 at 6:56 AM
Subject: HTML5 and 'Web and TV' (was Re: HTML5 Last Call May 2011 &
DASH/Adaptive Streaming
To: Mark Watson <watsonm@netflix.com>, Jean-Claude Dufourd
<jean-claude.dufourd@telecom-paristech.fr>, Glenn Adams
<glenn@skynav.com>, Richard Maunder <rmaunder@cisco.com>
Cc: public-web-and-tv@w3.org

Hi Mark, JC, Glenn and Richard,

Thank you for your active participation.

I think most of the IG participants would also have strong concern
over the relationship between HTML5 and 'Web and TV' activity, mainly
because of the difference in timeline.

As one of the IG co-chairs, I will talk about it with other co-chairs
soon and would ask the HTML-WG chairs or W3C team about appropriate
liaison between two activities.  In the meantime please feel free to
continue the discussion but be aware of the lack of the liaison
consensus among them on this early stage.

Now co-chairs have been working hard to review the result of the
second workshop and to prepare the tools for the IG.  Please wait a
little more for the tools coming.


On 2011/02/16, at 3:20, Mark Watson wrote:

> Discussion on handling multi-track media is already underway on both whatwg and HMLT5 lists. See for example Jeroen's post: http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2011-February/030454.html
> I think the intention is to include a solution to this. The deadline for solution proposals is 21 February.
> This would address choice of language, subtitles, views and accessibility tracks. One issue is that DASH has a flexible labeling scheme for track types based on URNs, wheras the assumption in the HTML discussions is to use a defined list of track types. Personally I think a reasonable resolution of this would be to define URNs for the HTML-specified types and leave it at that (rather than the opposite approach of persuading HTML to expose URN types from DASH.)
> Regarding trick modes, I am not sure what is missing ? The HTML5 media element has a "playbackRate" attribute which can be used to play at different rates, forwards or backwards.
> ...Mark
> On Feb 15, 2011, at 9:56 AM, Jean-Claude Dufourd wrote:
>> There is no question of including DASH technology in HTML5, just means to control DASHed media.
>> What some participants of the workshop defended was the inclusion of a way to deal, within HTML5, with various options offered by DASH, such as choice of bit-rate, audio, subtitles, as well as support for trick modes (a.k.a. VCR-like controls).
>> One possible solution is to add element/attribute syntax around the video object to allow that kind of control. Another solution is to add script APIs.
>> Best regards
>> JC
>> On 15/2/11 18:38 , Glenn Adams wrote:
>>> Even if it were done today, I doubt very much they would reference it from the HTML5 spec. There just isn't a strong reason to do so. Besides, they have chosen a technology neutral position with respect to both stream media formats and transports.
>>> Glenn Adams
>>> On Tue, Feb 15, 2011 at 8:56 AM, Richard Maunder <rmaunder@cisco.com> wrote:
>>> Hi,
>>> Interesting session in Berlin last week, thanks to all involved.
>>> While we wait from the IG process & tools to form, I was interested in the implications of the HTML5 Last Call for May, especially the window for getting any DASH baseline or other adaptive streaming requirement into the spec:
>>> http://www.w3.org/2011/02/htmlwg-pr.html
>>> I'm not very familiar with the W3C processes, but my reading of them suggests it would be unlikely in this round if not in the spec by May?
>>> Any thoughts on this?
>>> Best wishes
>>> Richard
>>> Legal boilerplate follows.....
>>> Any views or opinions expressed are solely those of the author and do not necessarily represent those of Cisco.
>> --
>> JC Dufourd
>> Directeur d'Etudes/Professor
>> Groupe Multimedia/Multimedia Group
>> Traitement du Signal et Images/Signal and Image Processing
>> Telecom ParisTech, 46 rue Barrault, 75 013 Paris, France
>> Tel: +33145817733 - Mob: +33677843843 - Fax: +33145817144
Received on Tuesday, 15 February 2011 21:23:17 UTC

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