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Proposed response to the WAIC public comment

From: Loretta Guarino Reid <lorettaguarino@google.com>
Date: Fri, 22 Oct 2010 16:26:21 -0700
Message-ID: <AANLkTima+He3U5OHz2H8Cyk8rCGf9B-omd4SP1S7q=tT@mail.gmail.com>
To: WCAG <w3c-wai-gl@w3.org>
WG, please review this to see whether I have accurately captured the
results of our discussion yesterday.

Thanks, Loretta



This is a question from WAIC(Web Accessibility Infrastructure
Committee in Japan) which is a successor to JIS working group. In
order to harmonize with WCAG 2.0, we need an answer from WCAG working

A video player is embedded in a web page. The author used the third
party video player to present video-audio content(synchronized media).

In this case, are the UI components of the video player also applied
to "Statement of Partial Conformance - Third Party Content"? The UI
components include "Play/Pause", "Stop" buttons, volume controls and
so on.

- Video-Audio content is under the author's control.
- But UI components are "uncontrolled content" which is not content
that is under the author's control.
- UI components may be updated without notice. After the update, even
if UI components won't meet SC anymore, it is not under the author's

One of the specific examples for this situation is YouTube player
APIs. There are many web pages which embed video-audio content by
using Youtube Player. UI components of Youtube Player are not under
author's control.

In my understanding, "Statement of Partial Conformance - Third Party
Content" is only applied when it is not possible to know at the time
of original posting what the uncontrolled content of the pages will
be. So, in the case of Youtube palyer, it is not applicable. But I'm
not sure...

We've got many questions on this point. In order to keep international
harmonization between WCAG and JIS, we have to confirm WCAG's


Proposed WG Response:

The WCAG Working Group discussed several issues raised by your comment:

* Is the video player covered by WCAG?

If the technology used to implement the video player were a plugin,
the UI to the plugin is *not* covered by WCAG. So the accessibility of
all the player controls etc. would not be covered by WCAG. If the
plugin controls aren't accessible (don't meet UAAG), then the content
isn't accessibility supported. If the content is a type for which
several plugins exist (and are available etc.), and some of them are
accessible, than it arguably is accessibility supported, because the
user has the choice to use one of those. But it's not a situation for
a partial conformance claim.

In the case of YouTube, however, the video player is implemented by a
scripting technology (Flash). The Flash player doesn't provide native
media controls. Rather, the controls must be included as part of the
content, and therefore *are* covered by WCAG. In this case, the
accessibility of those controls is part of WCAG and the author must
address it.

* Is the video player considered Third Party Content?

WCAG 2.0 says

"Sometimes, Web pages are created that will later have additional
content added to them. For example, an email program, a blog, an
article that allows users to add comments, or applications supporting
user-contributed content. Another example would be a page, such as a
portal or news site, composed of content aggregated from multiple
contributors, or sites that automatically insert content from other
sources over time, such as when advertisements are inserted

Your example describes the YouTube player as not under the author's
control; it may be updated without notice. The independent update of
the player does sound similar to the examples above, so it could be
considered third party content.

* Is the author responsible for the accessibility of the video player?

Since the author is including the video player on his page, his
conformance claim must cover it. If we consider it to the third party
content, WCAG gives two options:

1. A determination of conformance based on best knowledge. In this
case, the video player must be monitored, and if an update brings the
page out of conformance, the page must be repaired within two business


2. A statement of partial conformance can be made. Note that a
statement of partial conformance is a statement of *non-conformance*.
If the video player is considered third party content and the author
is not willing to address problems caused if the video player is
changed, then the page does not conform to WCAG 2.

Like any choice of widgets, the author should chose a player that is
accessible if possible.

Please let us know if there were other issues that we did not address.
Received on Friday, 22 October 2010 23:26:51 UTC

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