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Follow-up on Bug-11 ("Visual")

From: eric hansen <ehansen@ets.org>
Date: Thu, 15 Apr 1999 16:13:25 -0400 (EDT)
To: w3c-wai-gl@w3.org
Message-id: <vines.Bh0E+ZVY3rA@cips06.ets.org>
Follow-Up on Use of the Word "Visual"

Per the request of the Chairs, I have reviewed occurrences of the word 
"visual" and "visually" and find that the problems occurred mostly in areas 
I have already either marked as one of the 16 "Bugs" or were available in 
my 4/6/99 revision. Also the first occurrence of the word "visual" was not 
actually erroneous (though again, I did provide a revisions). I consider 
the problems mostly subsumed in other bugs. If my other changes are 
accepted, then the issue of "visual" will disappear. The word "visually" 
(usually as "visually-displayed text") seemed to be used appropriately.

Below is documented most of my analysis. 

==
In "Ensuring Graceful Transformation"

3/24/99:
Create documents that work even if the user cannot see and/or hear. Some 
content will be sensory-specific (e.g., audio, video, applets that present 
**visual** information), so provide equivalent information in forms suited 
to other senses as well. Note. This does not mean creating an entire 
auditory version of a site. Screen readers will be able to speak all 
information on a page as long as it is available in text. 

Possible Alternative: 
Create documents that work even if the user cannot see and/or hear. Some 
content will be sensory-specific (e.g., audio, video, applets that present 
**graphical** information), so provide equivalent information in forms 
suited to other senses as well. Note. This does not mean creating an entire 
auditory version of a site. Screen readers will be able to speak all 
information on a page as long as it is available in text. 

Recommendation:
"Visual" is OK, though I have provided a revision of this (I believe it was 
in my 6 April 1999 revision.):

"Create documents that work even if the user cannot see and/or hear. 
Provide information that serves the same purpose or function in ways suited 
to alternate sensory channels as well. Fortunately, one doesn't need to 
create a{EH: %^corrected spelling. 4/15/99} prerecorded audio version of a 
whole Web site in order for it be made accessible to individuals who are 
blind. Individuals who are blind can use screen reader technology, which 
speaks aloud all information on a page as long as it is available in text."

==

Title of Guideline 1

3/24/99:
Guideline 1. Provide equivalent alternatives to auditory and **visual** 
content

Recommendation:
"Visual" is only part of the problem. See next change regarding Long Title 
for Guideline 1.

==
Long Title of Guideline 1

3/24/99:
Provide content that, when presented to the user, conveys essentially the 
same function or purpose as auditory or **visual** content. 

Recommendation:

The word "visual" is not the problem in this case. My proposed change:
"Provide text equivalents that are synchronized with other communication 
elements." Reasons for change are documented under guideline 1 at: 
http://etsr.digitalchainsaw.com/wcagpub/r990324d.htm

==
Introductory Material for Guideline 1

3/24/99:
Although some people cannot use images, movies, sounds, applets, etc. 
directly, they may still use pages that include equivalent alternatives to 
the **visual** or auditory content. The equivalent information must serve 
the same purpose as the visual or auditory content. 

Recommendation:

"Visual" just one piece of the problem. See revision of introduction to 
guideline 1. It eliminates that use of the word visual.

"{EH: New 3/30/99. 20:15 hrs} Provide synchronized text equivalents.
Provide text equivalents that are synchronized with other communication 
elements. 

{EH: As you will see, with the minor changes that I have suggested, allow 
this guideline to focus on "text equivalents", which I think is a major 
advantage. The concept is so central the document that I think that it 
should not be diluted with consideration of non-text equivalents (except 
for a glancing reference in checkpoint 1.3, which could be moved to another 
guideline if necessary).}

{EH: Revised Intro to Guideline 1. The introductory material revises all 
paragraphs.}

"Failure to provide text equivalents and to sychronize them, as necessary, 
raises access barriers for many people with disabilities. {EH: Or, "Failure 
to provide synchronized text equivalents raises access barriers for many 
people with disabilities."}

"A text equivalent is a _communication element_ that, when rendered in any 
of three text-based ways (synthesized speech, braille, and 
visually-displayed text), fulfills the purpose or provides the function of 
one or more other communication elements. A text equivalent generally 
consists of text characters and is often written in a natural language or a 
close variant.

"The power of text equivalents lies in their capacity to be rendered in 
ways that are accessible to people from various disability groups using a 
variety of technologies.  Text can be readily output to speech synthesizers,
 _braille displays_, as well presented visually on computer displays and 
paper. Synthesized speech is critical for individuals who are blind and for 
many people with the reading difficulties that often accompany cognitive 
disabilities, learning disabilities, and deafness. Braille is essential for 
individuals who are both deaf and blind, as well and many individuals whose 
only sensory disability is blindness. Visually-displayed text is essential 
for almost all users who are deaf and is accessible to the majority of all 
Web users.

"A text equivalent of an image may consist of a description of the purpose 
or function of the image and be stored in the "alt" attribute of the IMG 
element. Longer descriptions, if necessary, can be stored in the file 
specified in the "longdesc" attribute of the element.  A text equivalent 
for a movie addresses both the visual and auditory aspects of the movie, 
including visual appearance (including action), spoken dialogue, and 
nonspeech sounds. 

"Text equivalents of time-based presentations (e.g., movies, animations, 
prerecorded audio, or multimedia presentations) must be synchronized with 
the primary presentation.

"Techniques for implementing text equivalents for different communication 
elements are described in the Techniques document."



=============================
Eric G. Hansen, Ph.D.
Development Scientist
Educational Testing Service
ETS 12-R
Rosedale Road
Princeton, NJ 08541
(W) 609-734-5615
(Fax) 609-734-1090
E-mail: ehansen@ets.org 
Received on Thursday, 15 April 1999 16:16:34 GMT

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