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Re: Question about image in the alt attribute

for

From: Jonathan Metz
Date: Jul 31, 2014 8:30AM


It has generally been my understanding that the W3C HTML specification is
a separate, albeit related and cross-referenced document that is required
to follow the guidelines recommended in WCAG. If WCAG echoed the same
requirements that the W3C was implementing word for word, what would be
the point of having a separate document? This is the approach taken with
other things, such as how ISO 14289 is a stricter interpretation of ISO
32000, but generally useless without it. Additionally, both ISO 14289 and
WCAG ignore elements of their parent documents that they deem to be
irrelevant to inaccessibility.

Jukka is right that the W3C specification explains why it’s requiring alt
text, and that would be great if we all argued about how to interpret HTML
specifications, (or whether the Stargate reference used was the best one
to recommend). Instead we debate interpreting WCAG and other supporting
guidelines to related content from HTML specification.

> The alt attribute has a job to do (to act as a replacement for an
>image).
> Trying to make it handle other affairs as well, no matter how relevant
> they might be in some contexts, disturbs it in doing its job.

This is at the very heart of what supporting documents like WCAG are
trying to do. For example, Jukka linked to requirements for images, but
WCAG specifically mentions non-text content. Even it’s definition does not
suggest it’s original authors intended it to only mean images. Recognizing
the benefits of alternate text beyond images, they recommend using it for
"any content that is not a sequence of characters that can be
programmatically determined
<http://www.w3.org/TR/WCAG20/#programmaticallydetermineddef>; or where the
sequence is not expressing something in human language
<http://www.w3.org/TR/WCAG20/#human-langdef>;.”

Used in this context, the Web Content Accessibility Guidelines are very
much disturbing an attribute to make it handle other affairs as well.
There are recommendations and examples the HTML specs mention all the
time, but they aren’t (usually) taken as an endorsement of the only way to
do something (A perfect example of this would be when to use <abbr> vs.
<dfn> for capitalization). The things that are related to accessibility
are provided in supporting documents from WAI or in WCAG itself.


Best,
Jon
(p.s. I understand there is a functional difference between WCAG and ISO)





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On 7/31/14, 6:30 AM, "Olaf Drümmer" < <EMAIL REMOVED> > wrote:

>Hi Steve,
>
>point taken!
>
>Olaf
>
>
>On 31 Jul 2014, at 12:17, Steve Faulkner < <EMAIL REMOVED> > wrote:
>
>> Hi Olaf,
>> I believe that was a quote from HTML 4
>> Regards
>> Steve
>>
>>> On 31 Jul 2014, at 11:59, Olaf Drümmer < <EMAIL REMOVED> > wrote:
>>>
>>> Hi Steve,
>>>
>>> a statement like "For user agents that cannot display images, forms,
>>>or applets, this attribute specifies alternate text. " needs to be
>>>fixed from my point of view, it needs to become more user centric. As
>>>an example just envision an ordinary PDF viewer. It could be used by a
>>>low vision person, but that person [heavily using magnification to read
>>>the text in it] might find it difficult to take in the overall
>>>appearance of an image. A tooltip could be provided (even in text form!
>>>but also via text to speech or other means) to make it
>>>easier/quicker/feasible for that person to take in the image.
>>>
>>> This implies two important aspects:
>>> - the person is using its sight (albeit via magnification)
>>> - on top of that that person is making use of the Alternate text to
>>>help with consuming an image
>>>
>>> The important thing is that the alternate text is available and can be
>>>put to work per the user's needs in a given situation. It hasn't got
>>>that much to do with limitations in a user agent.
>>>
>>> Olaf
>>>
>>>
>>>
>>>> On 31 Jul 2014, at 11:49, Steve Faulkner < <EMAIL REMOVED> >
>>>>wrote:
>>>>
>>>> Hi Olaf
>>>>
>>>> This doesn't need to be fixed in WCAG or HTML as it is not a
>>>>constraint
>>>> Refer to example scenarios where alt text may be useful
>>>>http://www.w3.org/html/wg/drafts/html/master/embedded-content.html#exam
>>>>ples-of-scenarios-where-users-benefit-from-text-alternatives-for-images
>>>>
>>>>> On 31 Jul 2014, at 10:43, Olaf Drümmer < <EMAIL REMOVED> > wrote:
>>>>>
>>>>> This is one of the areas where WCAG needs fixing - accessibility is
>>>>>not about disabilities of user agents.
>>>>>
>>>>> Olaf
>>>>>
>>>>>
>>>>>> On 31 Jul 2014, at 10:30, "Jukka K. Korpela" < <EMAIL REMOVED> >
>>>>>>wrote:
>>>>>>
>>>>>> 2014-07-31 10:56, Olaf Drümmer wrote:
>>>>>>
>>>>>>>> On 31 Jul 2014, at 06:56, "Jukka K. Korpela" < <EMAIL REMOVED> >
>>>>>>>>wrote:
>>>>>>>>
>>>>>>>> That's not what the alt attribute is for. It is to be presented
>>>>>>>>when the image is not displayed. It is ALTernative.
>>>>>>>
>>>>>>> I think you are misunderstanding something here. It is never about
>>>>>>>what is presented, it is always about what can be perceived.
>>>>>>>Furthermore supporting more than one channel (e.g. text to speech
>>>>>>>plus visual display) in the very same moment can be very useful.
>>>>>>>All this is not about "either or", it is about options (a minimal
>>>>>>>set of options, more is always OK), and each user should have
>>>>>>>mechanisms available to make use of these options in any fashion
>>>>>>>and combination.
>>>>>>
>>>>>> "For user agents that cannot display images, forms, or applets,
>>>>>>this attribute specifies alternate text."
>>>>>> http://www.w3.org/TR/html4/struct/objects.html#adef-alt
>>>>>>
>>>>>> "alt - Replacement text for use when images are not available"
>>>>>> http://www.w3.org/TR/html5/embedded-content-0.html#attr-img-alt
>>>>>>
>>>>>> The alt attribute has a job to do (to act as a replacement for an
>>>>>>image). Trying to make it handle other affairs as well, no matter
>>>>>>how relevant they might be in some contexts, disturbs it in doing
>>>>>>its job.
>>>>>>
>>>>>> Yucca
>>>>>>
>>>>>> >>>>>> >>>>>> >>>>>
>>>>> >>>>> >>>>> >>>> >>>> >>>> >>>
>>> >>> >>> >> >> >> >
>>>