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Checkpoint 1.2 clarifications

From: Joe Clark <joeclark@joeclark.org>
Date: Tue, 28 Aug 2001 08:28:51 -0400
Message-Id: <a05100302b7b13d78847e@[]>
To: w3c-wai-gl@W3.org
I suppose I should have noticed these before. However, WCAG does seem 
to be relying on WGBH to spot all the errors in discussing captioning 
and audio description, two fields of very little familiarity for most 

>Definitions (informative)
>Multimedia presentations include both audio and video tracks.

Not necessarily.

A radio broadcast could be captioned or at least transcribed. A 
silent videoclip could be described.

>Media equivalents present essential audio information visually 
>(captions) and essential video information auditorily (audio 

*through* captions and *through* audio descriptions.

But thank you for consigning the malapropism "auditory description" 
to the dustbin of history.

>*	Captions are text equivalents of auditory information from 
>speech, sound effects, and ambient sounds that are synchronized with 
>the multimedia presentation.
>*	Audio descriptions are equivalents

*audible* equivalents

(to maintain parallelism with the captioning definition)

>Benefits (informative)
>Captions provide auditory information for people who are deaf or who 
>have hearing loss.

No, they provide *text* information *about* the audio.

>Audio descriptions provide visual information for people who are 
>blind or who have low vision.

No, they provide *audible* information *about* the visuals.

>  Captions also provide auditory information for people who have 
>lowered the sound volume or are in a noisy environment.

Text information, not auditory.

>Audio descriptions also provide visual information for people who 
>are temporarilynot looking at the video presentation.

Audible information. "Temporarily not" is two words, and the sentence 
might read better as "Audio descriptions also provide audible 
information for people who happen not to be looking at the visual 
presentation or cannot see it for other reasons," like your video 
player can't keep up with it but gives you at least a half-arsed 
audio feed.

>*	Example 1: a movie clip with audio description and captions.
>A clip from a movie is published on a Web site. In the clip, a child 
>is trying to lure an alien to the child's bedroom by laying a trail 
>of candy. The child mumbles inaudibly to himself as he lays the 
>trail. When not watching the video, it is not obvious that he is 
>laying a trail of candy since all you hear is the mumbling. The 
>audio description that is interspersed with the child's mumbling 
>says "Charlie lays a piece of candy on each stair leading to his 
>room." The caption that appears as he mumbles is, "[inaudible 

If it's inaudible, how do we know it's mumbling? When mouth movements 
are unaccompanied by voice, a caption along the lines of [no voice] 
is customary.

>*	Example 3: a silent animation.
>An animation shows a clown slipping on a banana and falling down. 
>There is no audio track for this animation. No captions or audio 
>description are required. Instead, provide a text equivalent as 
>described in checkpoint 1.1.

It should be expressly permitted to record an audio description.
         Joe Clark | joeclark@joeclark.org | <http://joeclark.org/access/>
         Accessibility articles, resources, and critiques ||
           "I can't pretend to understand the mind of Joe Clark"
           -- Larry Goldberg
Received on Tuesday, 28 August 2001 11:33:46 UTC

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