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Re: Audio description requirements question

From: Phill Jenkins <pjenkins@us.ibm.com>
Date: Tue, 6 Nov 2012 18:03:40 -0600
To: w3c-wai-ig@w3.org
Message-ID: <OFD884FA30.CC15F367-ON86257AAE.007BDDE3-86257AAF.000057B4@us.ibm.com>
Jonathan said: ". . . If a multimedia presentation does not have 
sufficient pauses to allow for audio description, does it still meet Level 
AA if a media description is provided?"

What do you mean by your term "media description"?

A description of what part of the media and in what format? Do you mean a 
description of the video provided in a text transcript format?

WCAG 2.0 uses the term "audio descriptions', which means, in my words, 
descriptions of the video in an audio format synchronized in the media. 
The other way to provide descriptions of the video is with a text t
ranscript, which is an alternative to time-based media, providing an 
equivalent to the audio, video or both. 

1.2.3 Level A requires that either the audio descriptions - or - the text 
transcript be provided.  And remember that levels are not priorities, but 
levels of capability of implementation among other factors.  While 1.2.5 
requires the descriptions to be in an audio format and synchronized in the 
media, 1.2.7 is all about extending those audio descriptions when there is 
insufficient pauses.  So it would seem to me that you meet the criteria in 
1.2.5 only when the audio descriptions are provided.  But if you are 
asking if providing a text transcript is meeting the success criteria in 
1.2.5 because there is insufficient pauses in the audio to be able to 
provide audio descriptions - I would say not - because the level AA is 
trying to increase the availability of alternatives in formats that 
benefit the end user by specifically requiring the audio descriptions. 
Now, having said that, I believe it is a concern to me that "how much" of 
the audio descriptions must be provided to meet 1.2.5. level AA when there 
is no or very limited pauses in the audio is not very effective in meeting 
the goal of providing the equivalent information. So, by providing the 
author/owner a choice in implementation levels due to 2008 or current 
capabilities, the WCAG working group or editors may need to clarify this 
success criteria and achieving level AA.  The Understanding resource for 
1.2.5 Note 2 does not really address the situation when pauses are not 
sufficient to provide an equivalent.  Most agree that is the reason for 
level AAA to either provide the extended audio descriptions (1.2.7) or a 
full text transcript alternative (1.2.8).  So, I think you are really 
asking how can I meet 1.2.5 and provide audio descriptions if there are 
insufficient pauses to provide them?  You can't - we have what I call a 
catch 22 situation in the current WCAG 2.0  - I can meet level A and AAA, 
but I'm not able to meet AA if there are insufficient pauses in the audio. 
 Of course, the devil is in the detail of the term "sufficient pauses". 
However, there is a comment we can make to the WCAG editors to add to 
1.2.3 and 1.2.5 the phrase ". . . description [that presents equivalent 
information] of the prerecorded video . . . " assuming that was the 
working group's intent. 

Here I've quoted the WCAG Success Criteria for multimedia, please note the 
terms "Live" versus "Prerecorded" and 'Audio-only' versus 'Video-only', 
all the terms have links to definitions in the glossary:

1.2.1 Audio-only and Video-only (Prerecorded): For prerecorded audio-only 
and prerecorded video-only media, the following are true, except when the 
audio or video is a media alternative for text and is clearly labeled as 
such: (Level A) 
Prerecorded Audio-only: An alternative for time-based media is provided 
that presents equivalent information for prerecorded audio-only content.
Prerecorded Video-only: Either an alternative for time-based media or an 
audio track is provided that presents equivalent information for 
prerecorded video-only content.

1.2.2 Captions (Prerecorded): Captions are provided for all prerecorded 
audio content in synchronized media, except when the media is a media 
alternative for text and is clearly labeled as such. (Level A) 

1.2.3 Audio Description or Media Alternative (Prerecorded): An alternative 
for time-based media or audio description of the prerecorded video content 
is provided for synchronized media, except when the media is a media 
alternative for text and is clearly labeled as such. (Level A) 

1.2.4 Captions (Live): Captions are provided for all live audio content in 
synchronized media. (Level AA) 

1.2.5 Audio Description (Prerecorded): Audio description is provided for 
all prerecorded video content in synchronized media. (Level AA) 

1.2.6 Sign Language (Prerecorded): Sign language interpretation is 
provided for all prerecorded audio content in synchronized media. (Level 
AAA) 

1.2.7 Extended Audio Description (Prerecorded): Where pauses in foreground 
audio are insufficient to allow audio descriptions to convey the sense of 
the video, extended audio description is provided for all prerecorded 
video content in synchronized media. (Level AAA) 

1.2.8 Media Alternative (Prerecorded): An alternative for time-based media 
is provided for all prerecorded synchronized media and for all prerecorded 
video-only media. (Level AAA) 

____________________________________________
Regards,
Phill Jenkins, 
Received on Wednesday, 7 November 2012 00:04:16 GMT

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