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Braille is NOT a Sub-Set of Tactile [media types & media groups]

From: Gregory J. Rosmaita <oedipus@hicom.net>
Date: Tue, 19 Jan 2010 20:18:27 +0000
To: public-canvas-api@w3.org, public-html-a11y@w3.org
Message-Id: <20100119201309.M39179@hicom.net>
this post is partial fulfilment of HTML Task Force ACTION-7

http://www.w3.org/WAI/PF/HTML/track/actions/7

entitled: "propose braille media type (as opposed to simply tactile) 
or sub-type after consulting with Braille-in-DAISY and others"

this publically archived post will enable me to point pertinent 
experts to a common starting point; i think the issues enumerated 
below need more investigation and discussion before they are 
broached with the CSS working group/Style Activity, gregory.

BEGIN ANALYSIS

tactile should be a seperate media type than braille;

tactile covers such items as thermoformed objects, such as maps; 
raised line illustrations and other tactile information that 
require no prior knowledge in order to be successfully interpreted 
by an indivdual; they are tactile illustrations, not a representation 
of natural language;

braille, on the other hand, is a representation of a specific natural 
language; in order to understand braille, prior knowledge of the 
national version of braille being rendered (or into which text is 
being translated);

braille is a fundamentally different category from tactile, and yet is 
not equivalent to text, as it is classified by CSS as belonging to the 
"grid" media group; one might, for example, provide a stylesheet 
to enable a user to "Emboss This", much as sighted users are served an 
@print stylesheet when they actvate a "Print This" link

what is needed in my opinion is a supplemental CSS media type named
which would belong to the "continuous or paged" media 
group, both interactive and static

the problem is that the term "tactile" is currently used by CSS to 
catagorize media groups by sensory type:

visual/audio/speech/tactile

there is precedent in that "audio" and "speech" are treated as 
discrete concepts, so too should "braille" and "tactile" be 
treated as the separate concepts they are...  there is great 
room for flexibility in this realm, as braille stylesheets 
are -- for the most part, if not all -- only theoretical at 
this point in time, despite the Braille Stylesheets Preliminary
Requirements Analysis:

http://www.w3.org/WAI/PF/braillecss.html

FOR REFERENCE:

CSS 2.1 defines the following media groups: 
http://www.w3.org/TR/2009/CR-CSS2-20090908/media.html#media-groups

 * continuous or paged. 
 * visual, audio, speech, or tactile. 
 * grid (for character grid devices), or bitmap. 
 * interactive (for devices that allow user interaction), or static (for 
   those that do not). 
 * all (includes all media types) 


CSS 2.1 defines the following media types:
http://www.w3.org/TR/2009/CR-CSS2-20090908/media.html#media-intro

 * braille
 * embossed
 * handheld
 * print
 * projection
 * screen
 * speech
 * tty
 * tv
Received on Tuesday, 19 January 2010 20:18:59 GMT

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