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Re: Conformance Level Clarification

From: Chris Ridpath <chris.ridpath@utoronto.ca>
Date: Tue, 15 Feb 2005 09:26:02 -0500
Message-ID: <236101c5136a$471a8a70$e29a968e@WILDDOG>
To: <jasonw@ariel.its.unimelb.edu.au>
Cc: "John M Slatin" <john_slatin@austin.utexas.edu>, "WAI WCAG List" <w3c-wai-gl@w3.org>

>  > Level 1 alt text would only be required to meet the level 1
requirements
>  > while level 2 alt text would be required to meet both level 1 and level
2
>  > requirements.
>
> The same as all other success criteria.
>
Currently, each success criteria does *not* have 3 levels of conformance. To
conform to a success criteria the author must meet the success criteria.
There's no room for going below or above what's defined in the SC - there's
no levels at the technology specific layer. I'm suggesting that we allow for
3 levels per success criteria.

> It might be argued that in dealing with complicated images, a short
> label should be provided in the ALT attribute and full detail in a
> document referred to by LONGDESC, but that's an HTML-specific
> constraint that can't be expressed in the WCAG success criteria, which
> have to apply across languages and formats.
>
I think there's consensus that a short description is provided by the ALT
attribute and the LONGDESC is used for a longer description. Yes, this is
HTML specific and should not be expressed in the general success criteria.
It goes in the technology specific layer.

> For example, how would you
> apply it to the SVG DESC element?
>
I'm not sure. The people that are working on the SVG technology layer would
have to make that determination.

> I would have thought that the definition of "text
> alternative" would exclude place-holder values at level 1. A
> place-holder value doesn't provide the same functionality or
> information as the non-text content.
>
Perhaps you're right. I could agree but I feel there is pressure to move
this sort of conformance test (placeholder text) up to level 2 so that's why
I suggested it there. This is why we need the 3 levels to work with.
Currently a conformance test is either in or out unless we resort to other
categories such as "optional" or "best practice". If we've got the 3 levels
then we can keep the test but move it around to the appropriate level and
there's no need for defining other categories.

Cheers,
Chris
Received on Tuesday, 15 February 2005 14:26:22 GMT

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