PDF Alternative Text
Figures in a PDF document need to have alternate text in order for a screen reader
to describe what the image is to someone who may be visually impaired. Make sure that
images in the document either have alternate text or are marked as an artifact. To
do this, do ONE of the following:
- Select Figures Alternate Text in the Accessibility Checker panel, and choose Fix from the Options menu. Add alternate text as prompted in the Set Alternate Text dialog box.
- Use the Tags panel to add alternate text from images in the PDF.
- Open the Content panel and right-click (Windows) or Ctrl-click (Mac OS) the content that you want to mark as an artifact. Then, select Create Artifact from the context menu. (To display the Content panel, choose View > Show/Hide > Navigation Panes > Content.)
Screen readers used by someone who may be visually impaired do not read the alternate
text for a nested element. Therefore, don’t apply alternate text to nested elements.
To remove alternate text from nested elements:
- Choose View > Show/Hide > Navigation Panes > Tags.
- Right-click (Windows) or Ctrl-click (Mac OS) a nested element in the Tags panel and choose Properties from the context menu.
- Remove both the Alternate Text and the text to which it's applied from the Object Properties dialog box, and then click Close.
When you have alternate text on a page, you must always make sure that the alternate text is an acceptable alternate representation of content on that page. If an element has alternate text, but then doesn’t contain any page content, there is no way to determine which page it is actually on. If the Screen Reader Option in the Reading preferences is not set to read the entire document, the screen reader will never read the alternate text, so it’s better to remove it.
- Right-click (Windows) or Ctrl-click (Mac OS) an item to check.
- Open it in the Tags panel. (To display the Tags panel, choose View > Show/Hide > Navigation Panes > Tags.)
- Remove the Alternate Text from the Tags panel for any nested item that has no page content.
Alternate text can’t hide an annotation. If an annotation is nested under a parent element with alternate text, then the screen readers do not see it. To fix this, remove the alternate text from the nested elements. To do this:
- Choose View > Show/Hide > Navigation Panes > Tags.
- Right-click (Windows) or Ctrl-click (Mac OS) a nested element in the Tags panel and choose Properties from the context menu.
- Remove the alternate text from the Object Properties dialog box, and then click OK.
If this error occurs, it means there is another element on your page other than a figure that will require alternate text, such as some multimedia, an annotation, or a 3D Model. Make sure that alternate text is always an alternate representation for that content on the page. If an element has alternate text, but does not contain any page content, there is no way to determine which page it is on. If the Screen Reader Options in the Reading preferences is not set to read the entire document, then screen readers don't read the alternate text. To remove the alternate text:
- Choose View > Show/Hide > Navigation Panes > Tags.
- Right-click (Windows) or Ctrl-click (Mac OS) a nested element in the Tags panel and choose Properties from the context menu.
- Remove the alternate text from the Object Properties dialog box, and then click OK.