This is the second of a planned series of short posts about the use of Ally. You can find out more about Ally on the Royal Holloway staff intranet.
Images without descriptions
An image description, sometimes referred to as ‘alternative description’ or, more commonly, ‘alt-text’, is a textual alternative for an image. It makes it easier to connect the image to its context and allows learners with visual impairments – or those who do not have the bandwidth to download large content – to perceive the image.
It is easy to add an image to a Moodle course, and there is more than one way to do it. The quickest way to add an image to course front page is to drag-and-drop it. One unintended consequence of this approach is that Moodle does not present a dialogue box into which alt-text can be typed. This means that images can be accidentally published without alt-text. Furthermore, should learners on a course add images in this way to discussion forum posts, these too will be without the necessary descriptive text.
Images without alt-text will be flagged in Ally as: The image does not have a description
What does it mean?
The HTML code for an image with alt-text might be expressed as:
<img src="Flag-Australia.gif" alt="The flag of Australia">
Without alt-text, the code reads:
<img src="Flag-Australia.gif" alt="">
If an image does not have alt-text, learners who use screen readers or have not been able to download the image will have no means of understanding what, if anything, it is intended to convey. This creates an unnecessary barrier that may compound existing difficulties faced when trying to engage with online learning activities.
The good news is that Ally not only flags up missing alt-text, but makes it easy to add it without the need to wrestle with Moodle.
- Click on the image’s Ally Accessibility indicator
2. The Ally interface will open
3. Enter a clear description of the image
4. Click the Add button
Note: Avoid using the default Indicate image is decorative button, as this simply replicates the title of the image – which is not likely to be helpful.
5. The alt-text will be applied and the accessibilty of the image rechecked.
There are two schools of thought about applying alt-text to non-essential or decorative images:
- Add alt-text that simply informs the screen reader – and therefore your learner – that the image is decorative so they can disregard it
- Leave the alt-text blank so the screen reader quickly moves to the next piece of content
Some argue that adding unecessary alt-text slows down access and comprehension of web content for those using screen readers. Others may argue that having no alt-text is ambiguous – is the image decorative or did the author forget to add the alt-text?
The key here is learner-centred design and consistency. FInd out what your learners need and apply it throughout your course(s).