Re: LC-558, LC-559, and LC-560

Issues 558, 559, and 560 are all from Bruce Bailey and concern 1.3.2 (Any
information that is conveyed by color is also visually evident without
color) and 1.3.4 (Information that is conveyed by variations in
presentation of text is also conveyed in text, or the variations in
presentation of text can be programmatically determined).

In 559, he suggests that the techniques for Situation A in "How to meet
1.3.2" are too restrictive as the success criteria does not require that
the information conveyed by color is also conveyed in text. It simply
requires that the information conveyed by color is visually evident without
color. He also made the same comments in 558. And 560 is really a subset of
559. In commenting on the techniques document, he suggests in 560 that the
first technique for Situation A in "How to meet 1.3.2" is too restrictive
for the success criteria.

Situation A: If the color of particular words is used to indicate
information.
1. Ensuring that color encoded information is also available in text
2. Including a text cue whenever color cues are used

He suggests moving these techniques to SC 1.3.4.

It's true that these techniques are too restrictive in the absence of any
other techniques. But these techniques would be "sufficient" to meet the
SC. It's just that there are other techniques that would also be sufficient
to make the information conveyed by color visually evident without color.
So one option is to add one or more of these other techniques.

The other option is to change the success criteria to match the techniques
if we really meant you have to convey the information using text. This
would make 1.3.2 more consistent with 1.3.4 but it might mean we have to
re-issue last call. I don't really think this is what we meant because
Situation B in "How to meet 1.3.2" has a technique for using pattern in
addition to color to convey information in an image.

I recommend we add a technique

<proposal>
[alternative]
Add the following technique to Situation A in "How to meet 1.3.2"

3. Ensuring that when text color is used to convey information, the text
style is visually different without color.
</proposal>

Now back to 558. The above proposal deals with his comments about some of
the techniques belonging with 1.3.4 instead of 1.3.2.

He also mentions that the common failure in "how to meet 1.3.2" should be
associated instead with 1.3.4. In a followup phone conversation, Bruce
realized that the common failure comment was a mistake and should be
disregarded.

That leaves us with one thing in 558 to deal with - that 1.3.4 should be
Level 1 and 1.3.2 should be Level 2. It's not clear from his comment why he
thinks this but in our phone conversation, it seems that he believes that
information conveyed through changes in the color of text should also be
conveyed through "text", not just through some other change in the text
presentation such as bold, underline, or italics. But 1.3.4 allows the
information to be conveyed "either" through text or for the variations in
presentation of the text to be programmatically determinable. So moving
1.3.4 up to Level 1 would not achieve the desired goal either. It also
would not require any visual difference which is what we really wanted when
we moved the current 1.3.2 up from Level 2 where it was in the November
draft. (We decided this between January 17th and February 24th according to
the WCAG 2.0 history of changes but I can't find a specific resolution in
the minutes.)

So, I recommend that we reject 558 with the following proposed response:

<proposal>
[reject]
The intent of 1.3.2 is to require some kind of visual differentiator for
information that is conveyed using color. The differentiator can be either
other variations in the presentation of colored text (bold, underline,
italics, etc.), the addition of pattern to a colored area on an image, or
additional text that conveys the same information. If 1.3.2 is moved to
Level 2 and 1.3.4 is moved to Level 1 then there is no level 1 requirement
for visual differentiation at all as long as the color difference can be
programmatically determined. The working group determined that a visual
differentiator is important when information is conveyed with color because
users might not be able to perceive color differences. Variations in the
presentation of text, other than color, are already visually evident,
therefore the working group placed the requirements on non-color variations
in text at Level 2.
</proposal>



Andi
andisnow@us.ibm.com
IBM Accessibility Center
(512) 838-9903, http://www.ibm.com/able
Internal Tie Line 678-9903, http://w3.austin.ibm.com/~snsinfo

Received on Tuesday, 30 May 2006 18:49:04 UTC