[Bug 12590] New: @role=presentation for IMG should also require that @title is empty

http://www.w3.org/Bugs/Public/show_bug.cgi?id=12590

           Summary: @role=presentation for IMG should also require that
                    @title is empty
           Product: HTML WG
           Version: unspecified
          Platform: PC
               URL: http://dev.w3.org/html5/spec/content-models.html#table
                    -aria-strong
        OS/Version: All
            Status: NEW
          Keywords: a11y, aria
          Severity: normal
          Priority: P3
         Component: HTML a11y APIs (editor: Steve Faulkner, Cynthia
                    Shelley)
        AssignedTo: faulkner.steve@gmail.com
        ReportedBy: xn--mlform-iua@xn--mlform-iua.no
         QAContact: public-html-bugzilla@w3.org
                CC: mike@w3.org, laura.lee.carlson@gmail.com,
                    public-html-wg-issue-tracking@w3.org,
                    public-html@w3.org, xn--mlform-iua@xn--mlform-iua.no,
                    bhawkeslewis@googlemail.com, public-html-a11y@w3.org


The #table-aria-strong table currently says that

]]
       img element whose alt attribute's value is empty
   = presentation role    [[

There seems to be agreement (see message from Richard [1]) that, in addition to
@alt being empty, the @title attribute must also be absent or empty.  We also
have a disputed Decision which says that a non-empty @title should be counted
as equal to a non-empty @alt: Even if the Decision is disputed, the Decision
anyhow supports the view that a non-empty @title makes the IMG
non-presentational. AT behaviour also supports this view - see JUSTIFICATION
sectoin below.

Thus, please update the  #table-aria-strong table to say something like the
following:

]]
       img element whose alt attribute's value is empty
       and whose @title attribute is empty or omitted
   = presentation role    [[

JUSTIFICATION:

It is too simplistic to draw a direct link beween empty @alt and
role=presentation. As explained in bug 12587, the effect of applying <img
title="Lorem ipsum" role=presentation> is - in praxis - different from using an
empty <img title="Lorem ipsum" alt="">: In the former case the IMG is
completely hidden. In the latter case, the @title might be presented to the AT
user.

For example VoiceOver treats <img title="Lorem ipsum" alt=""> as
non-presentational, due to the presence of @title, which it reads to the user.
Also, inside links, the IMG's title is used by VoicOver (and probably also
several other AT, see Steve's research from 2005 [2] ) if there is no @alt. The
same goes for @alt in <area> elmements, where it seems VoiceOver actually
prefers @title over @alt.

Bug 12587 points to an example in the wild [3] which examplifies the issue: 

<a href="[link]">
  <img src="http://images.apple.com/support/iknow/images/i_call_adv.png"
   alt=""  title="Apple Support Express Lane">
</a>

[1] http://lists.w3.org/Archives/Public/public-html-a11y/2011May/0042
[2] http://www.paciellogroup.com/resources/articles/WE05/forms.html
[3] http://support.apple.com/kb/HT3669

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Received on Tuesday, 3 May 2011 17:35:54 UTC