Technique ARIA15:Using aria-describedby to provide descriptions of images
About this Technique
This technique relates to 1.1.1: Non-text Content (Sufficient).
This technique applies to technologies that support Accessible Rich Internet Applications (WAI-ARIA).
Description
The objective of this technique is to provide descriptions of images when a short text alternative does not adequately convey the function or information provided in the object.
A feature of WAI-ARIA is the ability to associate descriptive text with a section, drawing, form element, picture, and so on using the aria-describedby
property. Descriptive text provided using aria-describedby
is separate from the short name provided using the alt
attribute in HTML. An advantage of providing long descriptions using content from the same page as the image is that the alternative is available to all, including sighted people who do not have assistive technology.
Like aria-labelledby
, aria-describedby
can accept multiple id
s to point to other regions of the page using a space separated list. It is also limited to id
s for defining these sets.
Examples
Example 1: Describing an image
The following example shows how aria-describedby
can be applied to an image to provide a long description, where that text description is on the same page as the image.
<img src="ladymacbeth.jpg" alt="Lady MacBeth" aria-describedby="p1">
<p id="p1">This painting dates back to 1889 and is oil on canvas. It was created by
John Singer Sargent, and represents ...</p>
Related Resources
No endorsement implied.
Tests
Procedure
- Examine each image element where a
aria-describedby
attribute is present. - Examine whether the
aria-describedby
attribute programmatically associates an element with its text description, via theid
attribute on the element where the text to be used as the description is found. - Examine whether the combined text equivalent and associated text description accurately describe or provide the equivalent purpose to the object.
Expected Results
- #1, #2, and #3 are true.