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Re-word Checkpoint 4.8

From: Madeleine Rothberg <Madeleine_Rothberg@wgbh.org>
Date: 2 Dec 1999 12:08:57 -0500
Message-ID: <n1267985630.42289@wgbh.org>
To: "W3C-WAI-UA" <w3c-wai-ua@w3.org>
I have another old issue to revisit. 

Checkpoint 4.8 Allow the user to control video frame rates. [Priority 1]

I propose re-wording this to:
Checkpoint 4.8 Allow the user to control the rate of presentation of
videos and animations. [Priority 1]
For example, provide an accessible interface to play a video or animation
at half-speed for increased comprehension by those with cognitive
impairments or deaf viewers who are reading captions.

I believe that rate of presentation is closer to the intent of this
checkpoint than frame rate, which might produce the desired effect for
animation, but won't for video.

I had previously mentioned this issue but I neglected to follow up.
Here is my previous comment, followed by Ian's reply.

MR: Apologies if I missed discussion on this (can't find any in this
year's mailing list archives). Why do users want to control video
frame rates? If what is meant is that users want to speed up and slow
down video to improve comprehension or save time, say that. Changing
frame rate changes the quality of video but may not effect how fast
content goes by. The only access issue I'm aware of for frame rates is
that sign language requires high frame rates to be comprehensible, but
that is an authoring issue and a bandwidth issue, I think.

IJ: Perhaps you should join a call and explain this. I believe
there was an issue with cognitive disabilities and the need to
slow down for comprehension. Or, in a video presentation with
links, for example, to be able to change the rate of presentation
so that someone with motor difficulties could interact with the
presentation at a rate of his or her choosing.


Madeleine Rothberg
The CPB/WGBH National Center for Accessible Media
Received on Thursday, 2 December 1999 12:07:26 UTC

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