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Re: Video Poster image

From: Silvia Pfeiffer <silviapfeiffer1@gmail.com>
Date: Sat, 11 Dec 2010 15:10:16 +1100
Message-ID: <AANLkTi=K9=dO+gcUxQAx=Mkro6VL_A84yz=wbxj2zG8B@mail.gmail.com>
To: David Singer <singer@apple.com>
Cc: Matt May <mattmay@adobe.com>, "Gregory J. Rosmaita" <oedipus@hicom.net>, HTML Accessibility Task Force <public-html-a11y@w3.org>, Maciej Stachowiak <mjs@apple.com>, Ian Hickson <ian@hixie.ch>
I think this discussion is potentially very confusing to non-sighted
users which may be the cause for the call for extra descriptions on
the @poster attribute. I think we have not clearly enough described
what effect exactly the @poster attribute has to a sighted user.

Firstly, I'd like to chime in with David: the term "poster" is very
misleading and does in no way shape or form mean a "movie poster",
i.e. one of those big paper posters created as advertisements for
movies. Those posters do exist as images and may be used as a
representative image on a video through the @poster attribute, but
that is not actually the point.

The point is that to a sighted user who looks at the a video on a Web
page it is not possible to distinguish whether the image frame that
they are seeing is one taken out of the video itself (anywhere - be
that the first frame or any other one) or whether it is a completely
different image. And because to the sighted user this image represents
the video, for all accounts and uses it *is* the video. What is shown
on that image to sighted users is what they expect from the video and
it is therefore what needs to be described in a short/long text
representation of the video. The fact that in the HTML code there may
or may not be a @poster attribute is completely transparent to the
sighted user. In fact, the sheer concept of a poster image would be
something that doesn't exist to a sighted user - to them it is the
image that represents the video and therefore it needs to be part of
the text that represents the video in sheer analogy. After all, it is
not the markup that we need to make accessible, but the experience.

Hope this helps clarify.


On Thu, Dec 9, 2010 at 7:28 AM, David Singer <singer@apple.com> wrote:
> I think you answered your own question: a blank space is visually unappealing. Indeed, the clue that the poster provides is "if you play this, you'll see something which features Lassie the dog", and the alt text and other accessibility aids should 'say' *exactly the same thing*.
> On Dec 8, 2010, at 14:10 , Matt May wrote:
>> What is the point in displaying a poster for a video in the first place? If it didn't present any meaningful information on its own, it wouldn't exist--we'd just have a blank space there with a play button. The fact that the poster provides helpful cues to sighted users as to whether or not they want to play the video (or more to the point, that it _exists_ to provide those cues) is evidence that it can, if properly specified, provide similarly meaningful cues to users of other modalities.
>> -
>> m
>> -----Original Message-----
>> From: public-html-a11y-request@w3.org [mailto:public-html-a11y-request@w3.org] On Behalf Of David Singer
>> Sent: Wednesday, December 08, 2010 9:04 AM
>> To: Gregory J. Rosmaita
>> Cc: HTML Accessibility Task Force; Maciej Stachowiak; Ian Hickson
>> Subject: Re: Video Poster image
>> I respectfully disagree.
>> I'm sorry, perhaps the word 'poster' is misleading.  In the HTML case, it is not an advertisement for a resource which is 'miles away', as a movie poster is (it's on a billboard, the movie is in a cinema), it's a proxy for the video before it's played in the same place.  I think it conceptually wrong to have alternatives for proxies -- the proxy and the alternative are peers.
>> On Dec 8, 2010, at 10:46 , Gregory J. Rosmaita wrote:
>>> aloha, david!
>>> the video is the video itself, full stop...  the poster image is akin
>>> to either a conventional movie poster (with the names of actors, other
>>> credits, copyright info, and running time -- the two are NOT the same,
>>> just like the DVD/Bluray disc you put into a player is the "video"
>>> portion of the equation, the packaging usually contains a version of the
>>> film's original release poster with added information which most
>>> probably will NOT be included in a single frame, which may be the
>>> "title card" for the movie, the first frame of the opening credits,
>>> or simply a black frame containing nothing that can be consumed by
>>> anyone...
>>> thus, video and poster are VASTLY different concepts, and while i
>>> agree that the 3 points you highlighted need to be urgently
>>> addressed, so too does the video and poster issue -- a single
>>> frame of a video may be completely meaningless to those who cannot
>>> visually process it, making the information contained in the poster
>>> essential -- especially if it indicates that audio description,
>>> closed captioning, and multiple language tracks are available
>>> gregory.
>>> ----------------------------------------------------
>>> The optimist thinks that this is the best of all
>>> possible worlds; the pessimist knows it is.
>>> ----------------------------------------------------
>>> Gregory J. Rosmaita: gregory@linux-foundation.org
>>> Vice-Chair & Webmaster, Open Accessibility Workgroup
>>> http://a11y.org/              http://a11y.org/specs/
>>> ----------------------------------------------------
>>> ---------- Original Message -----------
>>> From: David Singer <singer@apple.com>
>>> To: HTML Accessibility Task Force <public-html-a11y@w3.org>
>>> Cc: Maciej Stachowiak <mjs@apple.com>, Ian Hickson <ian@hixie.ch>
>>> Sent: Wed, 8 Dec 2010 09:27:52 -0600
>>> Subject: Re: Video Poster image (was RE: DRAFT analysis of fallback
>>> mechanisms for embedded content ACTION-66)
>>>> I agree, a poster IS the video.  we should not encourage bad
>>>> practices by pretending/allowing otherwise.
>>>> I have three questions about annotating audio/video resources:
>>>>    can I
>>>>       (a) provide a short "alt" text? for video
>>>>       (b) provide a long description?
>>>>       (c) link to a transcript?
>>>> These seem to be more important, to me, than worrying about
>>>> whether the poster is semantically different from the video.
>>>> David Singer
>>>> Multimedia and Software Standards, Apple Inc.
>>> ------- End of Original Message -------
>> David Singer
>> Multimedia and Software Standards, Apple Inc.
> David Singer
> Multimedia and Software Standards, Apple Inc.
Received on Saturday, 11 December 2010 04:11:11 UTC

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