- From: Loretta Guarino Reid <lorettaguarino@google.com>
- Date: Mon, 25 Feb 2008 14:57:21 -0800
- 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 UTC