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Terminology, Etc. - Sections 1 and 2

From: <Ehansen7@aol.com>
Date: Tue, 28 Dec 1999 01:29:51 EST
Message-ID: <0.7c1b7269.2599b2df@aol.com>
To: w3c-wai-gl@w3.org, w3c-wai-au@w3.org, w3c-wai-ua@w3.org
CC: ehansen@ets.org
To: AU List, CG List, UA List
From: Eric Hansen
Re: Terminology, Etc. - Sections 1 and 2

The following suggestion relate to the three sets of guidelines, though the 
"old" versions of checkpoints are  those of the Authoring Tools guideline 
document.

This document has four sections.

Section 1 - Key terminology
Section 2 - The Big Picture 
Section 3 - A Taxonomy of Accessibility Information
Section 4 - Usage of Terminology in the WAI documents

=====
Section 1 - Edits for the Authoring Tool Guidelines

Note 1. Unless otherwise noted, these suggestions pertain to the 18 Dec 1999 
draft of the Authoring Tool Guidelines, though much of this also pertains to 
all the documents.

Note 2. Usage of some specific terms is detailed in Section 4. The terms are: 
(a) "Accessibility Information",  (b) "Alternative Information", (c) 
"Equivalent Alternative(s)" or "Alternative Equivalent(s)".  

#1. Eliminate the term "Alternative information"

Eliminate it since, according to the definition in the Authoring Tool 
glossary, this is apparently equal to "equivalent alternative".  I believe 
that this is used entirely within the two AU docs. See #2 below.

#2. Fix the definition of "equivalent" in the ATAG glossary.

Comment: The current ATAG definition of "equivalent" raises a few issues. The 
ATAG definition focuses on the bi-directionality of the "equivalent" 
relationship between two pieces of content. This is like the first sentence 
of the WCAG definition of equivalent ("Content is "equivalent" to other 
content when both fulfill essentially the same function or purpose upon 
presentation to the user."). This is in contrast to the uni-directionality 
that is emphasized in the second sentence of the following WCAG 1.0 
definition ("Content is "equivalent" to other content when both fulfill 
essentially the same function or purpose upon presentation to the user. In 
the context of this document, the equivalent must fulfill essentially the 
same function for the person with a disability (at least insofar as is 
feasible, given the nature of the disability and the state of technology), as 
the primary content does for the person without any disability."). (This 
second sentence indicates that an equivalent is an "alternative", thus making 
the term "alternative equivalent" redundant.) I believe that the second WCAG 
sentence is more central to legitimate usage of the word "equivalent". Keep 
in mind that the first WCAG sentence could apply as well to alternative 
language information as to alternatives for accessibility purposes. The main 
justification that I can think of for the term "alternative equivalent" (or 
"equivalent alternative") is that it may help emphasize that we are referring 
to accessibility-related equivalents rather than to 
internationalization-related equivalents (even though the term alternative 
equivalent is probably redundant).  A legacy-related reason for using the 
term is that it is used in WCAG.

Note. I consider the distinction between "text equivalents" and "non-text 
equivalents" as more fundamental than the distinction between 
"unsynchronized" and "synchronized" equivalents. Essentially, "text" and 
"non-text" equivalents are types of equivalents but synchronization is simply 
a possible attribute of equivalents.


Old:
Alternative Information (Also: Equivalent Alternative)
Content is "equivalent" to other content when both fulfill essentially the 
same function or purpose upon presentation to the user. Equivalent 
alternatives play an important role in accessible authoring practices since 
certain types of content may not be accessible to all users (e.g., video, 
images, audio, etc.). Authors are encouraged to provide text equivalents for 
non-text content since text may be rendered as synthesized speech for 
individuals who have visual or learning disabilities, as braille for 
individuals who are blind, or as graphical text for individuals who are deaf 
or do not have a disability. For more information about equivalent 
alternatives, please refer to the Web Content Accessibility Guidelines 
[WAI-WEBCONTENT].

New:

Equivalent

Content is "equivalent" to other content when both fulfill essentially the 
same function or purpose upon presentation to the user. In a very general 
sense, the term equivalent could also refer to alternative natural languages 
versions of content for internationalization purposes. Yet in the context of 
this document, the equivalent must fulfill essentially the same function for 
the person with a disability (at least insofar as is feasible, given the 
nature of the disability and the state of technology), as the "primary" 
content does for the person without any disability. Equivalents may be "text 
equivalents" or "non-text equivalents". Text equivalents are expressed as 
text and can be rendered as synthesized speech, braille, or 
visually-displayed text. For example, short and long text equivalents for an 
images (i.e., "alt-text" or long description in HTML) and collated text 
transcripts (for movies) are required text equivalents. Auditory description 
is a non-text equivalent that must accompany movies and animations. 
Equivalents that include synchronization information as part of their 
definition may be called synchronized equivalents. Important synchronized 
equivalents include "auditory descriptions" and "captions". For more 
information about equivalents, please refer to the Web Content Accessibility 
Guidelines [WAI-WEBCONTENT].

#3. Add a definition of "alternative equivalent" in the ATAG glossary.

Old:

See old definition of "alternative information".

New:
Alternative Equivalent (or Equivalent Alternative)
The term "alternative equivalent" (or sometimes "equivalent alternative")  
includes equivalents and some other accessibility information such as 
redundant text links, and alternatives for layout tables. 
====
#4. Retain but refine the term "Accessibility information"

According to the Authoring Tool glossary, this is an overarching term that 
includes "equivalent alternatives".
See the taxonomy below:

Old:
Accessibility Information
Accessibility information is content, including information and markup, that 
is used to improve the accessibility of a document. Accessibility information 
includes, but is not limited to, equivalent alternative information.

New:
Accessibility Information
Accessibility information is content, including information and markup, that 
is used to improve the accessibility of a document. Accessibility information 
includes, but is not limited to, alternative equivalents.
====
#5. Fix the definition of "accessibility information".

I am not sure how many kinds of info this includes. See the taxonomy in the 
other memo.

Old:

"Accessibility Information"
"Accessibility information is content, including information and markup, that 
is used to improve the accessibility of a document. Accessibility information 
includes, but is not limited to, equivalent alternative information."


New:

"Accessibility Information"
"Accessibility information is content, including information and markup, that 
is used to improve the accessibility of a document. Accessibility information 
includes, but is not limited to, equivalents."

====
#6. Fix usage issues in checkpoint 3.3.

Old:
3.3 Ensure that prepackaged content conforms to Web Content Accessibility 
Guidelines [WAI-WEBCONTENT]. [Relative Priority]
For example include captions, an auditory description, and a collated text 
transcript with prepackaged movies. Refer also to checkpoint 3.4.
New:
3.3 Ensure that prepackaged content conforms to Web Content Accessibility 
Guidelines [WAI-WEBCONTENT]. [Relative Priority]
<CHANGE> For example, include captions, auditory descriptions, and collated 
text transcripts with prepackaged movies. Refer also to checkpoint 3.4. 
</CHANGE>
{OR}
<CHANGE> For example, include captions, auditory description, and a collated 
text transcript with prepackaged movies. Refer also to checkpoint 3.4. 
</CHANGE>

{Note. Generally, I think of "captions" (plural), auditory description 
(singular), and collated text transcript (singular) as covering what needs to 
be provided for each movie or animation. This is an editorial issue but 
should be consistent.}
====
#7. Fix the definition of auditory description.

Notes: 

1. It partially misses the idea that synchronization is part of the 
definition of auditory description. The point is NOT that an auditory 
description "must be" synchronized but rather that an auditory description IS 
synchronized. According to the prevailing definition, if it is not 
synchronized it is not an auditory description (though the pieces might 
legitimately be called "auditory descriptions" [plural]). 
2. The current definition is not clear about the meaning of "low-bandwidth 
equivalent".  I suggest deleting this since this seems to imply that an 
auditory description is the same as an auditory rendering of a collated text 
transcript, which it is not.
3. The changed version emphasizes that the synthesized voice is "generally" 
generated in real time.

Old:
"Auditory Description"
"An auditory description provides information about actions, body language, 
graphics, and scene changes in a video. Auditory descriptions are commonly 
used by people who are blind or have low vision, although they may also be 
used as a low-bandwidth equivalent on the Web. An auditory description is 
either a pre-recorded human voice or a synthesized voice (recorded or 
automatically generated in real time). The auditory description must be 
synchronized with the audio track of a video presentation, usually during 
natural pauses in the audio track."

New:
"Auditory Description"
"An auditory description is an auditory equivalent of the visual track (of a 
movie or animation) that is synchronized with the auditory and visual tracks. 
Auditory descriptions are generally spoken during the natural pauses in an 
audio track.{Or "An auditory description is an auditory equivalent of the 
visual track of a movie or animation. It is synchronized with the auditory 
and visual tracks, generally being spoken during the natural pauses in the 
auditory track.} Auditory description is essential for many people with 
visual disabilities and is also helpful for people using devices that cannot 
display movies or animations visually. An auditory description is generally 
either a synthesized voice generated in real time or a prerecorded human 
voice. As an auditory equivalent of the visual track, an auditory description 
provides information about actions, body language, graphics, and scene 
changes.
====
#8. Fix the definition of captions.

Use "auditory track" rather than "audio track" and "visual track instead of 
"video". This is more in keeping with the regular usage. 

If we knew that captions would be required for audio-only presentations, then 
that should also be added to the definition. But since it has not happened 
yet, I suppose that we need to leave it out.

Old:
"Captions"
"Captions are essential text equivalents for movie audio. Captions consist of 
a text transcript of the audio track of the movie (or other video 
presentation) that is synchronized with the video and audio tracks. Captions 
are generally rendered graphically and benefit people who can see but are 
deaf, hard-of-hearing, or cannot hear the audio."

New:
"Captions"
"Captions must be  provided for movies and animations. Captions consist of a 
text transcript of the auditory track of a movie or animation that is 
synchronized with the visual and auditory tracks. Captions are generally 
rendered graphically along with the visual track and benefit people who can 
see but are deaf, hard-of-hearing, or cannot hear the audio."


 
Section 2 - The Big Picture

This is an attempt to give a big picture of the WAI guidelines documents. 
This picture does not necessarily reflect the views of WAI or its members. It 
is just an attempt to see where the guidelines are and where they might be 
heading.

Section A: Home Turf - Assumptions and Limitations the Current WAI Guidelines 
Documents

In general, the documents assume that:

1. Web content is ordinarily delivered via visual and auditory media and is 
usable without significant modification by individuals who have no 
disability. 
2. Mouse and keyboard are the main input devices for nondisabled access. 
Assistive technologies already do a fairly good job of emulating or 
facilitating mouse or keyboard input. Relatively minor modifications to Web 
content are required for individuals with motor/physical/movement 
disabilities.
3. "Text", particularly as natural language, is the premier method of 
expressing content so that it can be rendered in accessible ways (synthesized 
speech, braille, visually-displayed text). By requiring text equivalents for 
non-text elements, Web content can be made available to individuals who rely 
on synthesized-speech-only media (blind but unable to read braille), 
braille-only (deaf-blind), and visually-displayed-text-only (deaf who are 
able readers and may have difficulty  in processing pictures or other 
graphical materials).
4. Web accessibility for the broad range of other disabilities can be 
addressed through combinations of the regular visual and auditory 
presentations, visually-displayed text equivalents, auditory rendering of 
text equivalents, and braille rendering of text equivalents. This includes 
many people who:
(a) have visual disabilities but are partially sighted, especially if they 
read braille, 
(b) have hearing disabilities but some residual hearing, 
(c) have learning or cognitive, or other disabilities
5. While what constitutes an "equivalent" may vary according to factors such 
as disability type and technology used (see WCAG definition of "equivalent"), 
only one text equivalent is generally needed for each non-text element. In 
other words, a single text equivalent is suitable for many, if not all, 
disability/technology combinations.
6. It is preferable to implement accessibility features in all pages rather 
than have separate "accessible pages" for people with disabilities. 
7. Content is assumed to be largely general purpose and for general audiences.
8. Synthesized speech is an adequate (if not superior) substitute for 
prerecorded speech.
9. Prerecorded auditory descriptions are an adequate (if not superior) 
temporary substitute for synthesized-speech auditory descriptions.
10. Musical scores are not essential for accessibility of instrumental music 
"primary" content.

Section B: The Frontiers: Possibilities To Be Considered in Future Versions 
of the Guidelines:

Some of these frontiers are probably way off the edge and are probably wrong 
but may be useful in illuminating both the future possibilities and the 
assumptions/limitations of the current guidelines)

Following are future possibilities that could influence future versions of 
the guidelines.

1. Developers of user agents, authoring tools, and Web content need more 
guidance in providing the most useful equivalents in the most useful 
combinations. 
2. Some future Web content may have tactile media (braille and haptic or 
"kinesthetic"(?)), olfactory (smell) media, or other medium as their primary 
mode of delivery. Imagine, for example, a chiropractic treatment delivered 
over the "Web."
3. Web content may be intended for group delivery rather than merely to 
individuals. This is not an irrelevant issue since individuals with 
disabilities are sometimes accompanied by personal assistants, readers, and 
scribes. Furthermore, individuals with disabilities, like individuals without 
disabilities, may need to perform collaborative work in which collaborators 
have different access requirements. (Note. The current WAI bias toward (a) 
accessible original pages in contrast to (b) dual inaccessible/accessible 
page pairs partially deals with this issue.) 
4. Content must be made accessible to individuals who are deaf-blind and 
unable to use braille. Note that it may become feasible to output information 
to a mechanical person (or hand) that can sign (or at least fingerspell) 
content.
5. Content must be further optimized to make it accessible through haptic or 
force-feedback or "kinesthetic" devices. (I don't think that the guidelines 
have been specifically examined from this standpoint.). 
6. Other input and output devices become popular.
7. Musical scores come to be deemed an essential equivalent for instrumental 
music.
8. Non-text equivalents, such as sign language equivalents, come to be deemed 
an essential and feasible equivalents. For example, manual communication 
(sign language) movie equivalents for text would make content accessible for 
some deaf nonreaders.
9. Other equivalents that are currently not technically feasible become 
feasible.
10. Functionalities for improving the pronunciation of words by synthesized 
speech come to be deemed essential for disability access. (I am thinking that 
there should be a W3C specification for pronunciation and that it should be 
coordinated with the SMIL effort.)
11. For any given non-text element, one needs to be able to unambiguously 
locate its text equivalent(s). Or for any given text equivalent, one must be 
able to unambiguously locate its non-text element. Furthermore, if any 
equivalent is intended for a specific setting (e.g., disability/technology 
combination) as opposed to being completely general, then the setting must be 
made explicit. 
12. New classes of disability are tackled, e.g., reading disabilities, 
multiple hearing/tactile/sight disabilities.

Section C: Disputed Territories: Areas in Which We May Never Have Any Claim:

1. Nonreaders Who Cannot Benefit from Auditory Equivalents. This may include 
deaf nonreaders, especially if they cannot read manual communication 
delivered via movie.
2. Priority 1 Requirements for Non-Text Equivalents.

Section D: Foreign Territories: Areas That Are Best Left Entirely Alone, 
Except Through Ambassadorial Contact:

1. Issues that are not accessibility (i.e., disability access) issues, 
including issues that are strictly "usability" related or strictly 
"internationalization" issues.
2. Attempts to Make Content and Tools Usable To People Regardless of 
Educational Preparation.

<END>
Received on Tuesday, 28 December 1999 01:30:28 UTC

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