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

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.

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
>
>
>