W3C home > Mailing lists > Public > w3c-wai-gl@w3.org > October to December 2004

RE: 1.4 recommeded additions to wording

From: Yvette P. Hoitink <y.p.hoitink@heritas.nl>
Date: Thu, 4 Nov 2004 14:16:58 +0100
To: <w3c-wai-gl@w3.org>
Message-ID: <E1CPhTX-0002A4-MK@frink.w3.org>

Joe Clark wrote: 

[comment on audio contrast success criterium in guideline 1.4]

> 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.

Hello Joe,

Actually, I think neither blind people nor deaf people will appreciate
contrast in content that they cannot perceive :-) I do see the point you're
trying to make, though.

However, I do think that softer or no background noise in audio behind
speech *does* help accessibility for different types of people. Everyone
will likely have more trouble understanding what's being said if there is a
lot of background noise. This will be true especially for people with
limited hearing, cognitive problems or non-native speakers. 

Like you, I do not see the benefits for this guideline for foreground audio
other than speech. I think the line between foreground and background
content in non-speech audio is too blurry to be of practical use. Take a
musical performance for example, where there is a lead singer and background
vocals. This guideline would require the vocals to be 20 dB softer than the
lead singer, totally ruining the performance. This creates more problems and
does not solve any accessibility problems whatsoever.

Yvette Hoitink
Heritas, Enschede, the Netherlands
E-mail: y.p.hoitink@heritas.nl
WWW: http://www.heritas.nl
Received on Thursday, 4 November 2004 13:16:27 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:47:32 GMT