George Kerscher on braille versus tactile as media types

---------- Forwarded Message -----------
From: "George Kerscher" <kerscher@montana.com>
  To: "'Gregory J. Rosmaita'" <oedipus@hicom.net>
Sent: Wed, 20 Jan 2010 22:03:01 -0700
Subj: RE: braille versus tactile as CSS media types

Subject: Tactile versus braille

Dear All,

I was asked to comment on the issue of braille versus tactile graphics.

There is a huge difference between braille and tactile representations of 
information. Braille is an encoding of text and uses  different codes for 
specific purposes, such as literary works, textbooks, or maths. It it is 
also different in different regions of the world. Braille can be 
represented dynamically using a refreshable display or it can be embossed 
on paper.

Tactile representations can cover a wide range of information. Images, 
maps, flow charts, etc.  It is not been shown to be effective to present 
tactile graphics using a refreshable display.

George Kerscher Ph.D.
In our Information Age, access to information is a fundamental human 
right.
Secretary General, DAISY Consortium
http://www.daisy.org
Senior Officer, Accessible Technology Recording For the Blind & Dyslexic 
(RFB&D)  
http://www.rfbd.org 
Chair Steering Council Web Accessibility Initiative (WAI), a division of 
the W3C 
http://www.w3c.org/wai 
President, International Digital Publishing Forum (IDPF) 
http://www.idpf.org
Phone: +1 406/549-4687
Email: kerscher@montana.com

-----Original Message-----
From: Gregory J. Rosmaita [mailto:oedipus@hicom.net] 
Sent: Wednesday, January 20, 2010 11:33 AM
To: kerscher@montana.com
Cc: markus.gylling@gmail.com
Subject: braille versus tactile as CSS media types

aloha, george!

in discussions concerning the accessibility of the HTML5 CANVAS element,
i tried to make the point that there needs to be a distinction made 
between tactile and braille, just as there is a distinction in CSS 
between the speech and audio media types

if you agree with the following, could you please send a comment to 
public-html-a11y@w3.org stating that you support such a distinction?
if you think there is someone else whom you know who can speak 
authoritatively on this issue, please do not hesitate to forward 
this emessage to whomever you deem appropriate, so that i can get 
expert opinions into the record.

Rationale:
1. The term "tactile" covers items such as thermoformed objects, for 
example, maps; raised line illustrations and other tactile information 
that requires no prior knowledge in order to be successfully interpreted 
by an individual. This term connotes tactile illustrations and charts, 
not a representation of natural language.

2. The term "braille", on the other hand, specifically refers to 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 the text is being translated in accordance with user 
settings and preferences) is necessary.

Conclusion: "braille" is a fundamentally different category 
from "tactile". Although it is a representation of a natural 
language, "braille" is not equivalent to "text", as it is classified 
by CSS as belonging to the "grid" media group. What is needed, 
therefore, is a supplemental CSS media type which would belong to 
the "continuous or paged" media group and which could be classified as 
either interactive (refreshable braille) and static (embossed/final 
form braille).

a fuller exploration of the topic is available at:
http://www.w3.org/WAI/PF/HTML/wiki/Tactile_versus_braille

thank you very much, as always, gregory
--------------------------------------------------------------
You cannot depend on your eyes when your imagination is out of
focus.                                           -- Mark Twain
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Gregory J. Rosmaita: oedipus@hicom.net
   Camera Obscura: http://www.hicom.net/~oedipus/
          Oedipus' Online Complex: http://my.opera.com/oedipus
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Received on Thursday, 21 January 2010 15:34:56 UTC