To display alternative text for an image, enter the ac:alt attribute in the ac:image element as follows..Keep the alt text fairly short, as Confluence truncates long alt text entries.
<ac:image ac:alt="caDSR logo">
Positioning alt text
Experience has shown that Confluence can arbitrarily delete the alt text if you insert it randomly in the XHTML surrounding the image element, The best option is to insert it as shown above, right after ac:image.
An image inserted this way has alt text, as would be evident with the following image to one using a screen reader.
You can also add alt text by inserting the image using wiki markup. Refer to inserting an image on a page and changing the size.
