Actual Text – Alt Text – Expansion Text – Contents Key

PAC 2 Error

Errors involving alternative text can include:

  • Alternative text missing for Figure structure element; and
  • Alternative description missing for an annotation;

Other errors involving alternative text require human inspection.

Category

PDF/UA > Logical Structure > Alternative Descriptions

Failure Condition

Matterhorn Protocol Checkpoint 13: Graphics

Suggestion

  • The Actual Text attribute is used for text rendered in a way that a screen reader can not interpret – such as a graphic or a character that does not map to Unicode. Actual Text is short, frequently just one character, and can be used inline, for example as part of a paragraph or even part of a word. Examples include a drop cap or a non-standard list bullet.
  • The Alt Text attribute is a description of a figure that conveys information. It can be detailed, and as long as necessary to convey the same meaning as the figure.
  • Expansion Text is used to define an acronym or jargon term on first use.
  • The Matterhorn Protocol requires an alternate description in the Contents Key of every Link tag. For links to web pages, a good practice is to set the value of the Contents Key to the title attribute of the target page. The value type is always String.

Example PDF

Video version of this tutorial: