Definition

Alternative text is provided for visual content (e.g., via the [HTML] alt attribute).

Examples

Example 1 — EPUB 3
<meta property="schema:accessibilityFeature">
   alternativeText
</meta>
Example 2 — EPUB 2
<meta name="schema:accessibilityFeature"
      content="alternativeText"/>
Example 3 — Audiobooks
"accessibilityFeature": ["alternativeText"]

Explanation

The alternativeText value is used to indicate that all images and other non-text content (e.g., audio and video) that is relevant to understanding a publication includes a text alternative.

Alternative text provided using the HTML alt attribute.

<img src="rabbit.jpg" alt="Bugs Bunny" />

Presentational images (i.e., that are only used for purely display or ornamentation purposes) are excluded from the requirement for alternative text, so not every image or instance of non-text content will have a text alternative when this property is set.

A presentational image.

<img src="spacer.jpg" alt="" role="presentation" />

See the Image Descriptions knowledge base page for more information.

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