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RE: Proposed substantive change to media accessibility (Issue 2490)

From: Sean Hayes <Sean.Hayes@microsoft.com>
Date: Mon, 25 Feb 2008 23:28:32 +0000
To: Loretta Guarino Reid <lorettaguarino@google.com>
CC: WCAG <w3c-wai-gl@w3.org>
Message-ID: <90EEC9D914694641A8358AA190DACB3D1B498C9D11@EA-EXMSG-C334.europe.corp.microsoft.com>

It is modelled on 1.4.1, which does not rule out the use of colour, but requires that it not be the only means; but since media can convey a great deal more information than colour, for media it needs to be allowed that many minor details may be left out of the 'other means', just as they might be in an alt text description of an image.

In your specific example, it depends: on a sports news site reporting on the game, it would be blocking because the score of the game is information needed to comprehend the page and it is contained only in the media.

If the score and other relevant information was also given in a text article on the same page; then it might be non-blocking. Or if the game was one of a set of clips on a web page featuring the same player in different games, perhaps as a retrospective of the individual player's record over the years, it might be non-blocking because it is not necessary to comprehend the main article.

Or, if the score was incidental, e.g. the game was on the TV in the background of some other scene, and was not referred to by the actors, or used as a plot detail; then it would not be essential and could be left out.


Sean Hayes
Incubation Lab
Accessibility Business Unit
Microsoft

Office:  +44 118 909 5867,
Mobile: +44 7875 091385


-----Original Message-----
From: Loretta Guarino Reid [mailto:lorettaguarino@google.com]
Sent: 25 February 2008 22:57
To: Sean Hayes
Cc: WCAG
Subject: Re: Proposed substantive change to media accessibility (Issue 2490)

Sean,

I'm still having trouble understanding what you intend by "non-blocking":

   non-blocking content

   content in a web page which is not used as the only means of
conveying information needed to comprehend a web page or perform an
action needed to operate a web page.

If I have a Web page that contains an audio-video clip of last night's
basketball game, but I don't need to know the outcome of that game to
understand or operate the rest of the page, is that non-blocking?

Loretta

On Mon, Feb 25, 2008 at 12:19 PM, Sean Hayes <Sean.Hayes@microsoft.com> wrote:
>
>
>
>
> As discussed on the last teleconf, here is my proposal and rationale for
> re-levelling the media accessibility requirements.
>
>
>
> As you will recall in the previous email, In the current draft, at level A
> the possible options for synchronised media are:
>
> 1)      Provide a descriptive identification, a full text equivalent and
> caption all of the prerecorded audio
>
> 2)      Provide a descriptive identification, audio describe all of the
> prerecorded video and caption all of the prerecorded audio
>
> 3)      Provide a descriptive identification, a full text equivalent, audio
> describe all of the prerecorded video and caption all of the prerecorded
> audio
>
>
>
> Thus as we currently have it, a full text equivalent is seen as adequate
> access (indeed preferred - given its appearance again at AAA) at level A for
> people who have sight disabilities, but not for people who have hearing
> disabilities. I guess the rationale for this unevenness is recorded
> somewhere, I don't recall from the previous discussions what it was.
>
>
>
>  In the discussion, I raised as an issue the relative difficulties of
> producing each of these, and the real danger of media based websites
> disregarding WCAG as a whole because they will be unable to meet the caption
> and AD provisions, but that was rejected as a criterion for setting level,
> so I'm not going to dwell on it too much here; even though I think it's very
> important. But I do think the discrepancy above will eventually be picked up
> on as a fault of WCAG, once it becomes clear what the choices actually are.
>
>
>
> The full text alternative is very a high bar and exposes information in a
> way which would make most copyright holders very uncomfortable, so it seems
> incongruous to me at level A, even as an option, since these issues are
> certainly going to make it very problematic for most mainstream media
> providers; and option 2 above is probably going to be the only practical
> choice.
>
>
>
> In my previous email, I introduced a concept of 'non-blocking', which
> required that any information needed to correctly comprehend/use the page
> was not presented in media alone, and could be used as a more
> provider-friendly version of 'full text alternative' or 'text alternative'
> to operate at level A. This would also be more technology neutral and future
> proof; for example if a text based description technology came along, this
> would actually be prevented by the current rules which require AD to be in
> the soundtrack; even though it could be rendered by speech synthesis or
> delivered via a refreshable Braille device, which might be more appropriate
> in a mixed audience.
>
> Another example is requiring a text equivalent for an MP3 tune; it would
> seem that at minimum only a complete transcript of the lyrics is allowed to
> achieve level A (it's pretty ambiguous  whether the draft would allow
> captions in this case). It seems to me that users that are unable to hear
> would probably not be blocked on a 'pay to downlowd' music site if they
> could not read the lyrics of a snippet of a track, and that the name of the
> tune, artist and possibly some recording notes/parental guidance would
> probably be adequate for them to make a purchase decision.
>
>
>
> The current full text alternative requires:
>
> "document including correctly sequenced text descriptions of all visual
> settings, actions, speakers, and non-speech sounds, and transcript of all
> dialogue combined with a means of achieving any outcomes that are achieved
> using interaction (if any) during the synchronized media "
>
> And text equivalent requires:
>
> "programmatically determined text that is used in place of non-text content,
> or text that is used in addition to non-text content and referred to from
> the programmatically determined text"
>
>
>
> Both of these have serious IP implications for providers, whereas
> non-blocking would be:
>
> content in a web page which is not used as the only means of conveying
> information needed to comprehend a web page or perform an action needed to
> operate a web page.
>
>
>
> This ensures a basic level of accessibility in the presence of media and
> allows much more flexibility at level A. Moving captions and AD at level AA
> still allows jurisdictions which require them to set AA as the minimum bar,
> which I suspect will be the typical case, but allows providers which can't
> meet that to still have something to aim at, rather than not bothering at
> all.
>
>
>
>
>
> If we choose to address the issues above, then as I see it three possible
> plans would be:
>
>
>
> Plan 1 provide equity by allowing a full text equivalent for audio
> disabilities, where at level A the options for synchronised media would be:
>
> 1)      Provide a descriptive identification, and a full text equivalent
>
> 2)      Provide a descriptive identification, audio describe all of the
> prerecorded video and caption all of the prerecorded audio
>
> 3)      Provide a descriptive identification, a full text equivalent, audio
> describe all of the prerecorded video and caption all of the prerecorded
> audio
>
> At level AA, remove option (1) and add live to the other two options.
>
>
>
> Plan 2 provide equity by removing the option of full text equivalent for
> visual disabilities at level A, so that at level A the options for
> synchronised media would be:
>
> 1)      Provide a descriptive identification, audio describe all of the
> prerecorded video and caption all of the prerecorded audio
>
> 2)      Provide a descriptive identification and a full text equivalent
>
> At level AA add live to option (1).
>
>
>
> Plan 3 provide equity and allow a more readily achieved basic accessibility
> option, where at level A the options for synchronised media are:
>
> 1)      Provide a descriptive identification, and  ensure media is non
> blocking
>
>
>
> At level AA).
>
> Provide a descriptive identification, ensure media is non blocking , audio
> describe all of the prerecorded video and caption all of the audio
>
>
>
> My preference (obviously) is plan 3 so I have proposed text for that below,
> Plan 2 is IMO the one that will be 'real world' based on the existing draft
> and is a smallish delta from my previous post.
>
>
>
>
>
>
>
>
>
>
> 1.1.1 Non-text Content: All non-text content has a text alternative that
> presents equivalent information, except for the situations listed below.
> (Level A) How to Meet 1.1.1 Understanding 1.1.1
>
> Controls, Input: If it is a control or accepts user input, then it has a
> name that describes its purpose. (See also Guideline 4.1.)
> Media: If it is (1) synchronized media, (2) [audio-only] or (3) [video-only]
> content.
>
> Note: media is covered under Guideline 1.2, which requires specific forms of
> alternatives.
>
> Test, Sensory: If it is (1) a test or exercise that must be presented in
> non-text format, or (2) primarily intended to create a specific sensory
> experience, then text alternatives at least provide descriptive
> identification of the non-text content.
> CAPTCHA: If it is to confirm that content is being accessed by a person
> rather than a computer, then text alternatives that identify and describe
> the purpose of the non-text content are provided, and alternative forms of
> CAPTCHA using output modes for different types of sensory perception are
> provided to accommodate different disabilities.
> Decoration, Formatting, Invisible: If it is pure decoration, or used only
> for visual formatting, or if it is not presented to users, then it is
> implemented in a way that it can be ignored by assistive technology.
>
>
>
> Guideline 1.2 Media: Provide appropriate alternatives for media
> Understanding Guideline 1.2
>
>
>
> 1.2.1 Basic Media Alternative: A descriptive identification is provided for
> (1) synchronized media, (2) [audio-only] content or (3) [video-only]
> content; and that content is [non-blocking]. (Level A) How to Meet 1.2.1
> Understanding 1.2.1
>
>
>
>
>
>
> 1.2.2 Audio Description: Audio description is provided for all [prerecorded]
> [video] content in synchronized media. (Level AA) How to Meet 1.2.2
> Understanding 1.2.2
>
>
>
> 1.2.3 Captions: Captions are provided for all [audio] content in
> synchronized media. (Level AA) How to Meet 1.2.4 Understanding 1.2.3
>
>
>
>
>
>
> 1.2.4 Text Alternative: A text alternative that presents equivalent
> information of all [audio-only] content and all [video-only] content is
> provided (Level AAA) How to Meet 1.2.4 Understanding 1.2.4
>
>
>
> 1.2.5 Sign Language: Sign language interpretation is provided for all
> [audio] content in synchronized media. (Level AAA) How to Meet 1.2.5
> Understanding 1.2.5
>
>
>
> 1.2.6 Audio Description (Extended): Extended audio description is provided
> for all [prerecorded] [video] content in synchronized media (Level AAA) How
> to Meet 1.2.6 Understanding 1.2.6
>
>
>
> 1.2.7 Full Text Alternative: A full text alternative for synchronized media
> including any interaction is provided for prerecorded synchronized media.
> (Level AAA) How to Meet 1.2.7 Understanding 1.2.7
>
>
>
>
>
> Definitions:
>
>
>
> audio
>
> the technology of sound reproduction
>
> Note: audio can be created synthetically (including speech synthesis), or
> recorded from real world sounds, or both.
>
>
>
> audio description
>
> additional [audio] information that describes important visual details that
> cannot be understood from the main soundtrack alone
>
> Note 1: Audio description of video provides information about actions,
> characters, scene changes, on-screen text, and other visual content.
>
> Note 2: In standard audio description, narration is added during existing
> pauses in dialogue. (See also extended audio description.)
>
> Note 3: Where all of the video information is already provided in existing
> audio, no additional audio description is necessary
>
> Note 4: Also called "video description" and "descriptive narration."
>
>
>
> audio-only
>
> a time-based presentation that contains only [audio] (no [video] and no
> interaction)
>
> video-only
>
> a time-based presentation that contains only [video] (no [audio] and no
> interaction)
>
> live
>
> information captured from  a real world event and transmitted to the
> receiver within 30 seconds of the occurrence of the event
>
> Note: If information is completely computer generated, it is not live.
>
>
>
> pre-recorded: information that is not [live]
>
>
>
>
>
> synchronized media
>
> [audio] or [video] synchronized with another format for presenting
> information and/or with time-based interactive components, unless the media
> is an alternative to text which is clearly labeled as such
>
>
>
> video
>
> the technology of moving or sequenced pictures or images
>
> Note: video can be made up of animated or photographic images, or both.
>
>
>
> non-blocking content
>
> content in a web page which is not used as the only means of conveying
> information needed to comprehend a web page or perform an action needed to
> operate a web page.
>
>
>
>
>
> Sean Hayes
>  Incubation Lab
>  Accessibility Business Unit
>  Microsoft
>
>
>
> Office:  +44 118 909 5867,
>
> Mobile: +44 7875 091385
>
>
Received on Monday, 25 February 2008 23:28:38 GMT

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