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Re: Some comments on conformance levels in UA guidelines draft

From: <peter.b.l.meijer@philips.com>
Date: Thu, 9 Dec 1999 10:50:05 +0100
To: <schwer@us.ibm.com>
Cc: <w3c-wai-ua@w3.org>
Message-ID: <0056890007311305000002L952*@MHS>
Hi Rich,

I agree with you. 

It may just have been that my use of some terminology
unintendedly deviated from custom usage or your usage.

My use of the term "off-screen model" was meant to refer
only an (apparently idealized) situation where there is 
a single ("reference") off-screen model or architecture
per operating system, such that the hypothetical minimum-
functionality "reference" screen reader could use a subset
of that OSM to implement its functions. When this OSM is 
available (e.g., provided by the operating system vendor),
there would be no necessity to "reverse engineer" an OSM
architecture in order to implement the basic screen reading
functions. With reverse engineered OSM's for each user agent,
one would indeed expect many more compatibility problems.

Even with that single reference OSM, the user agent or
screen reader developer could of course still decide to
add "reverse engineering" from displayed screen content 
to add more-than-basic functionality (for instance to do
"something useful" with textures as rendered by advanced
3D graphics cards), but that would then be their problem
or opportunity to stand out from the crowd of UA's that
already conform at least to the basic "reference" screen 
reader functionality for basic accessibility.

Thus, I personally strongly support you where you say

> I agree that standardization for what you ask would be nice, however I
> would prefer to see the W3C WAI group continue to construct heterogeneous
> accessibility architectures that are not platform dependendent for
> accessibility. These constructs require considerably less
> reverse-engineering. The DOM is one example of that type of technology.

I wished there were also a platform independent video 
capture architecture and technology. I once hoped that
Java would soon be offering something like that, but at
the time I could no longer afford to wait for that to 
happen, if at all, and therefore I opted for a platform
dependent solution - for the time being.

Best wishes,

Peter Meijer


Real-Time Closed Captioning for the Blind - The vOICe
http://ourworld.compuserve.com/homepages/Peter_Meijer/caption.htm

> Hi Peter,
> 
> I am resending this because I sent it before I was done editing it.
> 
> First off I would like to state that I wrote the OSM for Screen Reader/2 so
> I understand what you are saying.
> 
> However, what I am also saying is that there are many screen readers with
> different OSM architectures. Furthermore, these OSM's become more
> convoluted as new technology, like the DOM, are made available to reduce
> the dependency on GUI drawing to OSM reverse engineered architectures. Even
> more important is the fact that these screen reader vendors feel that the
> way their specific OSM is designed is a key differentiator from
> competitors.
> Some of these like Screen Reader/2 contained things like menu hierarchies.
> 
> Tying engineered hooks back into these non-standard OSM architecture is a
> tall order and not one that should be required of user agent developers.
> Also, there are platforms like UNIX where there are no screen reader
> products that make use of an OSM.
> 
> I agree that standardization for what you ask would be nice, however I
> would prefer to see the W3C WAI group continue to construct heterogeneous
> accessibility architectures that are not platform dependendent for
> accessibility. These constructs require considerably less
> reverse-engineering. The DOM is one example of that type of technology.
> 
> Rich
> 
> Rich Schwerdtfeger
> Lead Architect, IBM Special Needs Systems
> EMail/web: schwer@us.ibm.com http://www.austin.ibm.com/sns/rich.htm
Received on Thursday, 9 December 1999 04:50:17 UTC

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