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Re: Action-219: Draft Response to MSE on Bug 23661

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Tue, 17 Dec 2013 08:39:20 +1100
Message-ID: <CAHp8n2k_7R6izZf_mjdaPM-cu-KnkHCCea2o9MrgTp9Krue7zw@mail.gmail.com>
To: Charles McCathie Nevile <chaals@yandex-team.ru>
Cc: Aaron Colwell <acolwell@google.com>, Steven Robertson <strobe@google.com>, "<public-html-media@w3.org>" <public-html-media@w3.org>, Adrian Bateman <adrianba@microsoft.com>, Mark Watson <watsonm@netflix.com>, Paul Cotton <Paul.Cotton@microsoft.com>

Why not try to fix it in the HTML spec first and thus imply the MSE
and all other such specs? It makes sense to me to fix this problem at
the root, not start with the leaves.

Is there a bug on the HTML spec for this yet?


On Tue, Dec 17, 2013 at 3:16 AM, Charles McCathie Nevile
<chaals@yandex-team.ru> wrote:
> On Thu, 12 Dec 2013 20:50:33 +0100, Steven Robertson <strobe@google.com>
> wrote:
>> YouTube intends to use MSE to improve accessibility by offering the user
>> the ability to switch content streams on the fly. Currently we do *not* plan
>> to implement this using AudioTracks/VideoTracks but rather by switching the
>> streams that get appended using JS. We are doing this so that the feature
>> can work reliably across all devices, including those which lack the
>> technical capability to support A/VTracks.
> Right, this is one valid implementation strategy. Note that it requires you
> to hold and mix on the server-side all the necessary pieces, which goes
> beyond providing the simple adaptations typically required to make MSE worth
> using.
> Note that signing video being developed by LaTrobe University (which
> currently has the largest deaf student population in Australia according to
> their own statements) to support hearing-impaired students is designed to
> meet the use case of allowing the student to reposition the two video tracks
> relative to each other, for example swapping video-in-video display for
> either video to be the "container", as well as moving the smaller video
> around on screen to cater for shifts in the visually important areas at any
> time. It seems the YouTube proposal would be unable to support these
> requirements efficiently, requiring a large amount of re-encoding to support
> a relatively small but mission-critical (for the University) audience.
>> This supports Aaron's objection;
> I don't think so.
>> conflating the user-facing goal of improving accessibility by having
>> the ability to select more appropriate content and one technical
>> implementation of that goal will limit the adoption of other
>> strategies
> It may well do so, and I agree that it would be a mistake to make such a
> conflation. For example by assuming that the approach taken by YouTube is
> available to and appropriate for everyone else - or by assuming that signed
> captioning can only be done with a second independent video track.
> (A third obvious technique is to use avatars, and transmit something that is
> not video at all over the wire - but while this has been considered a great
> idea for at least two decades, it's still in the "nice demo, but not really
> generally usable" stage as far as I know).
>> which have broader support.
> That's a judgement call that relies on a number of assumptions. Tto be fair,
> so is the word "typically" in the proposed resolution of the TF, and on
> reflection it seems that it should be easy to remove any bias toward one or
> other assumption in a result acceptable to all.
> But even if it turns out that we can prove one solution has and will have
> broader support, failing to adequately support legitimate alternative
> implementation strategies should be justified on some technical grounds. As
> you note above, assuming that a solution which works for many cases is the
> right one for everyone else too is a path to making specifications that
> unfairly distort perceptions about use cases that are appropriate to
> support.
> Please note that I am not accusing you of actually making that assumption,
> but it seems to me that upholding your objection would lead people to think
> in that direction.
> cheers
> Chaals
> --
> Charles McCathie Nevile - Consultant (web standards) CTO Office, Yandex
>         chaals@yandex-team.ru         Find more at http://yandex.com
Received on Monday, 16 December 2013 21:40:08 UTC

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