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FW: Proposed wording for SC 1.3.1

From: Gregg Vanderheiden <gv@trace.wisc.edu>
Date: Tue, 7 Mar 2006 15:14:31 -0600
To: <w3c-wai-gl@w3.org>
Message-ID: <014901c6422c$207dd6f0$ee8cfea9@NC6000BAK>
This would also help with our work on 4.1



1.3.1        HOW TO MEET would have to discuss BOTH accessing this
information from markup/user agent  AND accessing it directly from the


See old. 4.1.3 for material.  


 -- ------------------------------ 
Gregg C Vanderheiden Ph.D. 
Professor - Ind. Engr. & BioMed Engr.
Director - Trace R & D Center 
University of Wisconsin-Madison 
The Player for my DSS sound file is at http://tinyurl.com/dho6b




From: w3c-wai-gl-request@w3.org [mailto:w3c-wai-gl-request@w3.org] On Behalf
Of Loretta Guarino Reid
Sent: Tuesday, March 07, 2006 1:09 PM
Subject: Proposed wording for SC 1.3.1

John Slatin has a proposal for the wording for SC 1.3.1, based on the
discussion generated at last week's teleconference. Since John is off-line
this week, I'm forwarding it for him.


Proposed wording for SC 1.3.1:


Information and relationships conveyed through presentation can be
programmatically determined.


Definition of programmatically determined:


Programmatically determined Recognized by assistive technology that supports
the technologies in the chosen baseline 


Current wording for SC 1.3.1:


Perceivable structures within the content can be programmatically


Current definition of programmatically determined:


Recognized by user agents, including assistive technology, that support the
technologies in the chosen baseline </current>


Guideline 1.3 encourages authors to "Ensure that information and structure
can be separated from presentation." The success criteria (1.3.1-1.3.6)
define what must be true in order to ensure that information and structure
can be separated from presentation.

We define "information" as 

(1) a message to be sent and received, and

(2) a collection of facts or data from which inferences may be drawn. 

As of 2 March 2006, we define "structure" as 

(1) The way the parts of an authored unit are organized in relation to each
other and 

(2) The way a collection of Web pages or other primary resources is

We define "presentation" as "the rendering of the content and structure in a
form that can be perceived by the user."

Thus the proposed wording means that any messages to be sent and received,
any facts or data from which inferences may be drawn, and any relationships
among the parts of an authored unit, must be capable of being recognized by
assistive technology that supports technologies used to encode the
information and specified in the baseline. "Technology" is defined in the
glossary as markup language, programming language, style sheet, data format,
or API. The baseline is the set of technologies which the author may assume
are active in the user agent.

For HTML and other markup languages, the proposed wording does not require
markup for any information or relationship that is not conveyed through
presentation. (An example of such a relationship would be the use of some
literary symbol to give thematic coherence to a document or collection of
documents.) Again for HTML and other markup languages, markup would be
required to identify any information or any relationship conveyed through
presentation. (An example would be a phrase whose role as a section heading
is indicated by placing the phrase on a line by itself above some grouping
of information, or the logical relationships among numbers arranged in rows
and columns.)

When information and relationships are encoded using data formats that do
not allow for structural markup - such as images, audio files, animations,
and video - WCAG already requires text alternatives under GL 1.1. Where
these types of non-text content convey information or present relationships,
the information and relationships are conveyed by the text alternatives.
That is, the proposed SC does not require (for example) the use of SVG for
all images. But where SVG is used and the image conveys information or
relationships through presentation, the information and relationships must
be capable of being recognized by AT. And since that isn't possible now -
even the relationship between an image and its text alternative(s) can't be
recognized by AT yet - GL 4.2 comes into play and an accessible alternative
is required - an image that can be programmatically associated with a text


Loretta Guarino Reid


Adobe Systems, Acrobat Engineering 
Received on Tuesday, 7 March 2006 21:14:43 UTC

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