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Re: Default role of <IMG> should be "img"

From: Leif Halvard Silli <xn--mlform-iua@xn--mlform-iua.no>
Date: Mon, 13 Sep 2010 01:16:03 +0200
To: Benjamin Hawkes-Lewis <bhawkeslewis@googlemail.com>
Cc: Maciej Stachowiak <mjs@apple.com>, Steven Faulkner <faulkner.steve@gmail.com>, public-html-a11y@w3.org
Message-ID: <20100913011603334811.6a00cc09@xn--mlform-iua.no>
Benjamin Hawkes-Lewis, Sun, 12 Sep 2010 19:57:10 +0100:
> On 12 Sep 2010, at 19:33, Leif Halvard Silli wrote:

>> I don't know how an <img> that is not mapped to the a11y API is 
>> treated. Can someone tell?
> 
> UAs MUST not include "elements with role='presentation' that are not 
> focusable" in the accessibility tree.
> 
> http://www.w3.org/WAI.new/PF/aria-implementation/#mapping_general

What's the difference between "accessibility tree" and "accessible 
tree"? ARIA 1.0 says: [*]

]] the presentation role causes a given element to be treated as having 
no role, but does not cause the content contained within the element to 
be removed from the accessible tree [[
[*] http://www.w3.org/TR/wai-aria/complete#presentation

To not present the @alt text of <img role="presentation" alt=" Foo. "> 
seems equal to removing the "the content contained within the 
element".  So, while ARIA sees @alt as equivalent to @aria-label: [*]

]] If aria-label and aria-labelledby are empty or undefined, check for 
the presence of an equivalent host language attribute  [snip] For 
example, in HTML, the img element's alt attribute [[
[*] http://www.w3.org/TR/wai-aria/complete#textalternativecomputation

The @alt attribute in reality is much more than @aria-label: 1) it 
represents fallback, 2) it affects the semantics of the <img>. It is 
the element's content and not some add-on a11y attribute. I think the 
HTMLwg should point out to the ARIA specification authors, if they are 
not aware of it.
-- 
leif halvard silli
Received on Sunday, 12 September 2010 23:16:39 UTC

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