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Re: Checkpoint 1.1

From: Kynn Bartlett <kynn-edapta@idyllmtn.com>
Date: Sat, 28 Oct 2000 00:17:52 -0700
Message-Id: <a0500190cb62026c3eed9@[64.210.29.6]>
To: Jason White <jasonw@ariel.ucs.unimelb.EDU.AU>, Web Content Accessibility Guidelines <w3c-wai-gl@w3.org>
At 2:49 PM +1100 10/28/00, Jason White wrote:
><dt>1.1 Ensure that all content can be presented as text.

The word "ensure" always bugs me.  It's usually a sign of a guideline
which needs to be rewritten.

First stab:

Deliver content which can be presented as structured text.

>To achieve this,
>provide a text equivalent for every auditory, graphical or multimedia
>presentation which serves to convey meaningful information in the context
>of a document or user interface.

What do you think about using "visual" instead of "graphical"?  Auditory
is a modality, while graphical refers to a specific type of visual
information.

I'm not sure why the last phrase "in the context..." is needed.  (It's
needed below, but not here.)

><dd>Note that purely decorative or stylistic sounds and images are
>excluded from the above requirement.

Mmmm.  Bad idea.  Web designers have traditionally had a very hard
time with the idea of "purely decorative or stylistic" content.  A
better idea would be to state:

      Content which is entirely visual or auditory, which contains
      no additional information, may be considered "decorative."
      This content should be appropriately identified within the
      markup language.

>The purpose of a text equivalent is
>to provide a meaningful substitute for the auditory or graphical
>presentation in circumstances where the latter is inaccessible to the
>user. Thus, a well written text equivalent has the following
>characteristics:
><ol>
><li>So far as possible, it communicates the same meaning or information,
>in its context, as the auditory, graphical or multimedia presentation.

Drop the first phrase of this, as it makes things less clear.  We
might want to say:

      "<li>It fulfills the same function or conveys the same information,
       in its context, as the auditory, visual, or multimedia presentation."

><li>It does not describe the auditory or graphical presentation, except
>where such a description would best express the author's intended meaning.

Yes and no.  I feel we need to add another checkpoint as I'll describe
below.

><li>It is written in clear and concise language.

This should have a c.f. to the "clear and concise language" guideline/
checkpoint.

></ol>
>
>[end of proposal]


This proposal is good at describing "textual equivalents."  However, it
is not so good at describing "textual descriptions."  This is a
longdesc, an audible description track for a multimedia presentation,
and so on.   In fact, the second <li> above makes it clear that this is
not a checkpoint about descriptions.

Therefore, I propose that we need a checkpoint for textual
descriptions.  (I feel that this should be lower priority, in terms of
WCAG 1.0 priorities -- a 2 instead of a 1.)

Here's my first stab at a "textual descriptions" checkpoint:

1.X  Provide <term>textual descriptions</term> for audible, visual,
      or multimedia content.

The purpose of a textual description is to provide a complete
description of non-textual content, such as a multimedia presentation,
a visual image, or an auditory sound clip.  Unlike a textual
equivalent, the textual description does not directly replace the
contextual function of the non-textual content, although it does
supplement the textual equivalent.

Note:  Non-textual content which conveys no information beyond that
found in the textual equivalent does not require a textual
description.  For example, a simple image of a word, if the textual
equivalent is that word, does not require a textual description.

A well-written textual description has the following qualities:
<ol>
<li>It is available (directly or via a hypertext link) at all times
     at which the non-textual content is available.
<li>It is marked up correctly and accessibly in an appropriate
     markup language.  (For guidelines on synchronizing multimedia
     equivalents, see checkpoint 1.2.)
<li>It is written in clear and concise language, but must be an
     accurate and complete description -- so textual descriptions are
     often much longer than a textual equivalent.
</ol>

(Techniques for this:  LONGDESC/d-link for images, SMIL for multimedia,
audio transcripts for speeches, etc.)


Oh, and here's my rewritten "textual equivalents" checkpoint pulled
together from my comments above:

1.1  Deliver content which can be presented as structured text.

To achieve this, provide a text equivalent for all auditory, visual,
or multimedia content.

Content which is entirely visual or auditory, which contains
no additional information, may be considered "decorative."
This decorative content should be appropriately identified within
the markup language.

The purpose of a text equivalent is to provide a meaningful
substitute for auditory, visual, or multimedia content in
circumstances where the content is inaccessible to the user.

A well written text equivalent has the following characteristics:

<ol>
<li>It communicates the same meaning or information, in its context,
     as the auditory, visual, or multimedia content.
<li>It does not describe the auditory or graphical presentation,
     except where such a description would best express the author's
     intended meaning.  (See checkpoint 1.X for textual descriptions.)
<li>It is written in clear and concise language.  (See checkpoint
     X.X.)
</ol>



-- 
Kynn Bartlett <kynn@idyllmtn.com>
http://www.kynn.com/
Received on Saturday, 28 October 2000 03:54:21 GMT

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