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Re: Highlights from Call Today

From: Joe Clark <joeclark@joeclark.org>
Date: Thu, 7 Nov 2002 18:54:04 -0500 (EST)
To: WAI-GL <w3c-wai-gl@w3.org>
Message-ID: <Pine.BSO.4.40.0211071834260.3132-100000@ns1.seeto.com>

I'm worried about a whole lot of stuff in the WCAG 2.0 draft, but
I'm *really* worried about the discussions of captioning, which
suggest that authors haven't spent a lot of time watching captions.
As with many other diktats under the WCAG, it seems that captioning
is understood in a vague and abstract way by WCAG authors rather
than through lengthy lived experience. ("Captions-- that's words on
the screen, right?")

> 3. The presentation does not require the user to view captions and the
> visual presentation simultaneously in order to understand the content.

Well, then you're not dealing with captioning as it has ever been
known since the 1940s.

I suppose it could be argued that, if one is reading captions, one
is not "view[ing]... the visual presentation simultaneously." But
this does not correspond to the way people watch captioned TV, for
example. Research by Jensema--

Carl J. Jensema, Sameh El Sharkawy, Ramalinga Sarma Danturthi,
Robert Burch, and David Hsu, "Eye-movement patterns of
captioned-television viewers," _American Annals of the Deaf_,
145(3):275-285 (2000)

-- documents that people spend most of their time looking at
captions. Wow, what a surprise: Captions are there *to be read*. I
discourage WAI from attempting the Orwellian doublethink of
authorizing only those captions that can be ignored.

But people spend *less* time looking at captions the *longer*
they've been watching captioned TV, and that applied even to hearing
subjects who had never watched captions before in their lives: After
a few minutes of exposure, they had already gotten used to the
experience of watching captions and were spending more time looking
at the main picture.

I can tell you from experience that, while reading caption text, one
is nonetheless registering onscreen action through peripheral
vision, which must not be underestimated.

The requirement as written assumes a Bizarro world exists in which
you watch the caption, stop, watch the picture, stop, and repeat the
process. I believe few people alive today live on that planet.

A confounding factor here is that online captions can be "better
than reality," to use the nielsenism, in that you can pause the
video but, in theory, keep captions and/or descriptions running. I
suppose a strict reading of the requirement would force authors to
use *only* systems that permitted random cessation of picture and/or
captions at viewer whim.

The technical infrastructure really is not mature enough yet to
easily add captions to online video and easily watch them. (I'm
quite aware of Magpie, CCaption, and other software. It isn't
remotely as easy as adding Line 21 captions to television, let alone
as easy as watching Line 21 captions.) If this requirement were
enacted, WAI would be recapitulating its oft-made error of
*requiring* capabilites that do not commonly exist yet. (The
converse mistake is requiring a feature because a certain
present-day adaptive technology, which always seems to mean Jaws for
Windows, has it. Arguably this requirement is doing exactly that--
authors may have witnessed a demo of pausable online captions and
now they won't allow anything else.)

In what seems like a previous lifetime, I worked on a project that
decoded Line 21 TV captions and put them up on the Web. Such
captions would be outlawed by this provision even though they are,
in fact, captions. Moreover, the provision would *outlaw open
captioning altogether* because the captions and picture could not be
independently controlled.

Remove this section.

> Regard 1.2 Issues
> 2. all significant dialogue and sounds in multimedia content are
> captioned
> 3. (does not replace current #3)  For Web that is real-time audio-only,
> is not time-sensitive (e.g. not news, not emergency, etc.), and is not
> interactive, a transcript or other non-audio equivalent is available
> from the same URI.

Really? The same URI links to more than one thing?

> [at bottom of level 1 put]
> NOTE:  Exceptions for amateur productions etc. are not made here because
> they should be made in scope statements of policy setting agencies that
> are using these guidelines.

You do realize you are essentially outlawing Internet radio under
this plan?

*Every* audio stream online would have to be captioned or
transcribed. (What is "[an]other non-audio equivalent"? Semaphore?)

You do realize how many Web audio streams are in use now, even in
the U.S. after the Library of Congress-adopted royalty rates were

And you do realize that even *radio radio* is not required to be
captioned because it has no visual component? (Compact discs should
not have to be captioned for the same reason. But music videos
*should* have to be captioned because they *are* visual.)

Remove this requirement.

> exception: if content is rebroadcast from another medium or resource
> that complies to broadcast requirements for accessibility for the
> location it was broadcast, the rebroadcast satisfies the checkpoint if
> it complies with the other guidelines and if any existing accessibility
> information (such as captions or audio description) are rendered in web
> accessible format.   (See Level 3)

But the previous requirement bans any kind of captioning (and, I see
now, description) that cannot be turned off and on independently of
the picture.

> exception:   content is rebroadcast from another medium or resource has
> synchronized media equivalents for all audio and visual components of
> time dependent presentations.

Even if you rewrite this in English (another perennial WCAG
deficiency), I doubt it will make a whole lot of sense.

At a later stage of the full WCAG draft, I'll put in the three hours
it takes to provide full comments, but these issues are so pressing
and egregious, and the misunderstanding of captioning as it now
exists and should someday become so thorough, that I had to write
something right away.


  Joe Clark  |  joeclark@joeclark.org
  Author, _Building Accessible Websites_
  <http://joeclark.org/access/> | <http://joeclark.org/book/>
Received on Thursday, 7 November 2002 19:00:26 UTC

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