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Re: Empty vs no alt attribute (was Re: Baby Steps or Backwards Steps?)

From: Chris Blouch <cblouch@aol.com>
Date: Wed, 22 Aug 2007 09:36:53 -0400
Message-ID: <46CC3BF5.8000501@aol.com>
To: Marghanita da Cruz <marghanita@ramin.com.au>
CC: joshue.oconnor@cfit.ie, Sander Tekelenburg <st@isoc.nl>, HTMLWG <public-html@w3.org>, wai-xtech@w3.org, Don Evans <donald.evans@corp.aol.com>

The point I was trying to make was that while this supplemental 
information is good, as a true alternative description of the image it 
will fall short. Because of tool tips many web authors assume that alt 
is meant to give additional information for sighted users. The Assistive 
Technology community and most standards state that alt is to provide a 
text equivalent of the image. Of course some would argue that it's an 
impossible task to fully describe an image with words, but we can (and 
should) do better than just supplementing or augmenting it.

CB

Marghanita da Cruz wrote:
> Chris Blouch wrote:
>> Two aspects that seem to be overlooked in the discussion.
>>
>> 1. While there is an expectation that alt should be used for 
>> alternative equivalent text descriptions, in practice many browsers 
>> also use it for their popup "tooltips". This had lead some site 
>> authors to assume the purpose was more supplemental rather than 
>> alternative so they have stored additional meta data rather than real 
>> descriptions. Hence we see sites putting up "200x100 GIF Image July 
>> 12, 2007" as their alt text instead of a real content description. 
>> While this is incorrect use of the attribute, it is hardly a 
>> surprising assumption based on browser behavior.
>
> As an HTML author, I use the alt text as a caption - the kind of 
> additional information I tend to provide is Photographer or Artist's 
> name. The 200x100 should be provided in the  height/width attributes 
> of the image. Date is useful. I also assume the alt text is used to 
> index images. For example
> <http://images.google.com.au/images?gbv=2&svnum=10&hl=en&q=joel+tarling&btnG=Search+Images> 
>
>
> I would like to see all browsers display the alt text and other 
> attributes as a
> "mouseover" rather than with a right click for properties.
>
>>
>> 2. The problem with allowing images without alt attributes in some 
>> cases is that this essentially writes a loop hole into the standard. 
>> This then puts the burden on the standard to sufficiently constrict 
>> this loop hole such that it can't be abused. Hardening any loophole 
>> in a set of rules is difficult at best. We need look no further than 
>> laws of governing bodies for examples. As for the presence of alt 
>> tags being provisionally required, it would seem to be simpler to 
>> require them in all cases and then move debate to defining the 
>> presence and quality of the descriptions themselves, whether good, 
>> lousy or absent. At least this makes for any easy minimum test, a 
>> test which many tools already implement. Loopholes for poor or 
>> missing alt text would be a more fertile ground for work in the 
>> standard, but still a quagmire.
>>
>> I suggest that missing alt text should be called out in a manner that 
>> points out the author's mistake (either directly or via their tools). 
>> Something like "Author did not provide alternative text" or whatever 
>> wordsmithing is desired. This provides a means for discoverability by 
>> others to feed back to the source that something is wrong. If Grandma 
>> sees no tool tip or one that says just "undefined" she will ignore 
>> it. If she sees a message pointing fingers at my failure to do 
>> something right I might actually get an email from her. In other 
>> words, while the tooltip and non-descriptive errors for alt text may 
>> not directly enable users who need alternative content, it can enable 
>> other users to seek out resolution to a problem that was previously 
>> invisible to many.
>>
>> CB
>>
>> joshue.oconnor@cfit.ie wrote:
>>> Sander Tekelenburg wrote:
>>>  
>>>> I cannot imagine how alt="unknown" could be useful to anyone.     
>>>
>>> I am also at a loss to understand how this is useful. Is it expected
>>> that screen readers would read output "unknown" when they came across
>>> and image that used the attribute in this way?
>>>
>>> Josh
>>>
>>>
>>>   
>
>
Received on Wednesday, 22 August 2007 13:37:47 GMT

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