- From: Joe Clark <joeclark@joeclark.org>
- Date: Wed, 3 Nov 2004 17:05:26 +0000 (UTC)
- To: WAI-GL <w3c-wai-gl@w3.org>
This has always been on the wrong track and is only getting worse. I expect you'll all continue to pretend I never told you that; I've been consistent about it for months. > Level 3 Success Criteria for Guideline 1.4 > > - Audio content does not contain background sounds or the background sounds > are at least 20 decibels lower than the foreground audio content, with the > exception of occasional sound effects. [V] You have no proof whatsoever that this guideline actually provides accessibility benefit; there is no evidence at all that it can be met in the real world; the figure of 20 dB is purely arbitrary. It seems the entire guideline is a sop to anticipated criticisms that Blind People Get Good Contrast But Deaf People Don't! Well, that's because the disabilities are intrinsically different. > I had an action item to provide recommendations on 1.4 based on the open > issues and my research. Until we come up with an alga rhythm much of this > guideline is up in the air. One person recommended an extensive research > study. (Bug#996) Ideally that would be a good idea. I wouldn't mind joining > some people but it would require a team to conduct the size of study he is > suggesting in order to get a statistically meaningful sample size. He also > suggests it would require a statistician. And I strongly doubt it would prove a benefit. Until such study is done, the Working Group must delete its guideline, since it implies here that the whole shebang is hypothetical. > Who Benefits from Guideline 1.4 (Informative) > > Individuals with low vision can easily read characters in the content even > if they don't have the wide field of view Visual field is unrelated to colour perception. > or full range of color perception used by fully sighted persons to > separate text from background images. As I've explained for a year and a half-- even at the Toronto f2f, where Ben later went right ahead and pretended I had never proved my point-- colour deficiency requires accommodation only in confusable colours. In short, foreground and background matter only in the red/green and blue/green ranges. After several years of looking, I have found only rare examples of confusable colours used in confusable ways on the real Web that the Working Group either ignores or hates. Accessibility for colour-deficient persons is a question of confusable wavelengths and has nothing per se to do with foregrounds and backgrounds. > <new> This will also aid > comprehension for individuals with cognitive disabilities who benefit > from easy discernment of text. OK, great, but every sighted person, according to the worldview of this guideline, requires "easy discernment of text." > Visual contrast also helps individuals with hearing impairments who are > aided by clear visual representation of information </new> Prove it. This sounds like grandstanding. What does being deaf have to do with psychologyof reading in this context? -- Joe Clark | joeclark@joeclark.org Accessibility <http://joeclark.org/access/> Expect criticism if you top-post
Received on Wednesday, 3 November 2004 17:05:33 UTC