Re: HTML Action Item 54 - ...draft text for HTML 5 spec to require producers/authors to include @alt on img elements.

hi Jgraham
>That would appear to preclude requirements such as:
>"The alt attribute [...] must contain a text alternative that serves the equivalent purpose as the image. What is to be considered an equivalent purpose, depends on the way an image is used."[1]

well, no, there are methods for deciding the appropriateness of  text
alternatives according to the context the image is used in. These are
described in WCAG 2.0 for example.

What there is not a method for is divining the intent of an author for
why he/she did not provide a text alternative for an image..

regards
stevef

2008/5/21 James Graham <jg307@cam.ac.uk>:
> Steven Faulkner wrote:
>>
>> hi J graham,
>>
>>  >That doesn't seem so far away from many other non-machine checkable
>>>
>>> conformance requirements in the spec.
>>
>>
>> Seems like a good reason to revisit any examples of requirements in
>> the spec and provide requirements that are practical to independently
>> test conformance , rather than make requirements that cannot be tested
>> by anybody other than the author.
>
> That would appear to preclude requirements such as:
> "The alt attribute [...] must contain a text alternative that serves the
> equivalent purpose as the image. What is to be considered an equivalent
> purpose,
> depends on the way an image is used."[1]
>
> Since only the original author can be a definitive judge of the purpose of
> the
> image.
>
> I would argue that requiring knowledge of author intent does not prevent a
> conformance requirement being useful; such requirements can still increase
> the fraction of authors who do something well; this is the social
> engineering aspect of conformance requirements that I have previously
> discussed [2]. It does prevent services with no access to out-of-band
> information handing out badges to proclaim conformance, but it's not clear
> to me what the value of such badges is supposed to be, especially in the
> case where the conformance requirements have been watered down to meet the
> the capabilities of badge-providers.
>
> What _is_ dangerous is trying to encourage certain practices that require
> knowledge of the author's intent using conformance requirements that do not.
> In this case it is likely that the author will optimise to the letter of
> conformance and fail to actually achieve the goal that the spec authors had
> in mind.
>
>
> [1] http://esw.w3.org/topic/HTML/Action54AltAttribute
> [2] http://lists.w3.org/Archives/Public/public-html/2008May/0242.html
>
> --
> "Eternity's a terrible thought. I mean, where's it all going to end?"
>  -- Tom Stoppard, Rosencrantz and Guildenstern are Dead
>
>



-- 
with regards

Steve Faulkner
Technical Director - TPG Europe
Director - Web Accessibility Tools Consortium

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Received on Wednesday, 21 May 2008 20:06:59 UTC