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

From: Loretta Guarino Reid <lorettaguarino@google.com>
Date: Mon, 25 Feb 2008 14:57:21 -0800
Message-ID: <824e742c0802251457o3b8d0cffm5991710fa8f2c4db@mail.gmail.com>
To: "Sean Hayes" <Sean.Hayes@microsoft.com>
Cc: WCAG <w3c-wai-gl@w3.org>

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 22:57:37 GMT

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