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Re: Alternate text for images having caption adjacent


From: Denis Boudreau
Date: May 30, 2014 3:17PM

Hi everyone,

On May 29, 2014, at 5:22 PM, Jared Smith < <EMAIL REMOVED> > wrote:

> On Thu, May 29, 2014 at 11:57 AM, Rakesh P wrote:
>> Consider If alt="" is used instead of "Image of or photo of Jared" in
>> alternate text, screen reader will not announce that an image of Jared
>> is available in the web page.
> Correct, this is the intention of alt="". The fact that it's a photo
> of me as opposed to text of "Jared Smith" is not really important.

This is precisely what I have been advocating for years. That is, until @steveofmaine (https://twitter.com/steveofmaine) threw an unexpected monkey wrench into my clearly defined little world a couple of weeks ago.

Whether we choose to provide a null alt attribute value to pictures of people’s portraits on a web page all boils down to one's interpretation of what "purely decorative images” actually means. Luckily, WCAG 2.0 provides a definition of "pure decoration” that goes like this: an image "serving only an aesthetic purpose, providing no information, and having no functionality” (http://www.w3.org/TR/WCAG20/#puredecdef). Seems simple enough, right?

I’m sure most would agree that pictures of people right next to their name mostly serve aesthetic purposes. Pictures allow most of us to know what the person actually looks like, but we can’t exactly use the alt text value of an image to describe how the person physically looks. That would be awkward! Therefore, the alt text ends up repeating the person’s name and consequently, provides no real additional information that the adjacent text doesn’t already provide. Which, I assume, is why Jared was saying it’s not really important.

However, going back to the definition of “pure decoration” and looking into the concept of having no functionality, I now question whether or not a portrait of a person does, in fact, provide functionality. And I think it does. When we decide a photo should be marked up with alt=“” because the person’s name is right next to the image, we’re taking away what seems to be two functionalities from non-sighted screen reader users:

1. The ability to locate a person’s info based on the fact that it’s right next to his or her picture. Pictures, like headings or other objects in the page, provide structure. If a screen reader user has been told there’s a picture of the person on the page and they don’t know that person's name, they might want to search the page through images to find it. Assuming they don’t know what that person’s name is, searching for images and looking for text right next to it could be an efficient way to search the page. When we make the image invisible to screen reader users, then users cannot use the image anymore to quickly find the information about the person. Relying on null alt text takes that functionality or ability away.

2. The ability to actually locate the picture, and download it (for whatever purpose) is another thing we take away from these users when we choose to go with null alt text. If you can't know a picture is available on the page because authors have decided to make it invisible to you, you can’t do anything with it / about it. By assigning a null alt value to an image that in fact, does convey some kind of information (this is what this person looks like), we take away the non-sighted users’ ability to do something with that image. That, too, seems to be a functionality we’re taking away from non-sighted screen reader users.

Which is why I now believe that such photos need to have descriptive alt text, and that it has some degree of importance.

No having said that, I’m not saying those functionalities are the most important things in the world, but they’re functionalities nonetheless… and who would we be to decide whether or not users actually need those images?

I think there’s a real difference between a purely decorative image used for a border and a portrait and as such, the latter should not count as purely decorative images. I think we need to make sure portrait images do have alt text values assigned to them: it would mean a little repetition in the content, but then so be it. Personally, I’d rather risk giving a little too much to users, rather than actually taking something away from them.


Denis Boudreau,
Web Accessibility Avenger
DEQUE Systems Inc.
Tel: +1 (514) 730-9168
Web: www.deque.com