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Decision on CfC: Comments on the MSE CR

From: <janina@rednote.net>
Date: Thu, 7 Jan 2016 11:39:45 -0500
To: HTML Accessibility Task Force <public-html-a11y@w3.org>, W3C WAI Accessible Platform Architectures <public-apa@w3.org>
Message-ID: <20160107163945.GI26112@opera.rednote.net>

This decision pertains to the CfC published to the APA Working Group,
with advice of the HTML-A11Y Task Force at:


This CfC drew several messages of support, and several suggesting
perfecting edits which have been adopted.  Therefore, this CfC is agreed as
revised below. APA will now forward the following comments on the MSE CR document at:


Thanks to all who provided editorial suggestions on the draft comments.

Revised Comments

The Accessible Platform Architectures (APA) Working Group and the
HTML-A11Y Task Force offer the following accessibility related comments
on the MSE Candidate Recommendation (URI above):

1.)	The diagram in this document should be made accessible. There
are several ways to achieve this, including accessible vector graphics
with SVG, a link to an external description (standard <a href> or
@longdesc), or an in-page description of the graphical content.

	a.)	We provide for your reference a draft textual diagram
	description, though our draft requires enhancement as per b.)
	below. The draft description is available at:


	b.)	In addition to a textual description of your diagram for
	the benefit of those readers who cannot see it, wWe find the
	diagram also does not clearly convey its meaning and may benefit
	significantly from redesign. Please reconsider what you're
	trying to convey and determine if there is a more intuitive way
	to present the data.  Please clearly label your switches,
	connector endpoints, and relationships, e.g. What are the three
	dots under the video decoders? Are all the audio decoder
	switches open or is that a drawing error? What is the green
	circled X that the audio decoders are pointing to? What are the
	triangles? What is the meaning of the different colors of
	SourceBuffers? What is the viewer expected to learn from this

	c.)	Please consider creating this diagram using SVG. We
	believe it is actually an excellent candidate for the accessible
	graphic markup approaches being defined by the joint ARIA and
	SVG Task Force.[2] One member of this TF has already offered to
	assist, should you decide on SVG.

2.)	We would request greater use of prose to describe what the API
is doing. This is needed both to help the reader understand what is
being specified, but also to test whether the proposed API actually
meets its intended purpose.

3.)	We believe the MSE is not the appropriate specification to show
how multiple media objects, such as the primary video plus a
sign-language translation video plus captions plus described video are
unencrypted (EME) and synchronized, even when each comes from a
different server.  However, we believe the W3C needs a high-level
overview of how our various specifications fit together to deliver the
total user experience defined by HTML and by the Media Accessibility
User Requirements (MAUR).[1] We request your assistance in creating this
high-level overview document, and in using alternative media examples
where appropriate across W3C media specifications in ourder to
illustrate for authors and user agent developers how W3C specifications
work together to meet the widest possible assortment of user needs.

Thank you for your consideration of our comments.

Janina Sajka, APA Chair and HTML-A11Y Co-Facilitator

[1] http://www.w3.org/TR/media-accessibility-reqs/
[2] http://www.w3.org/WAI/PF/svg-a11y-tf/


Janina Sajka,	Phone:	+1.443.300.2200
		Email:	janina@rednote.net

Linux Foundation Fellow
Executive Chair, Accessibility Workgroup:	http://a11y.org

The World Wide Web Consortium (W3C), Web Accessibility Initiative (WAI)
Chair, Accessible Platform Architectures	http://www.w3.org/wai/apa
Received on Thursday, 7 January 2016 16:40:12 UTC

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