1.2.5 Audio Description (Prerecorded)

Introduction¶

This document provides information about the related Acquia Optimize check:

• Video has audio description.

What¶

Videos that contain important visual information must provide an audio description. This ensures that users who are blind or have low vision can understand key visual elements that are not conveyed through dialog alone.

An audio description is a spoken narration added to a video that describes:

• Key actions
• Scene changes
• On-screen text
• Important visual content that is not explained in the dialog.

This differs from captions, which transcribe spoken words but do not describe visual content.

When is this applicable?¶

This check applies to pre-recorded videos that include important visual elements that users need in order to understand the content.

Why¶

Videos often rely on visual elements to convey important information. Without an audio description, users who cannot see the screen miss critical details.

For example, in a video tutorial that demonstrates how to adjust settings on an app:

• If the instructor says, "Click here," without a description for what or where here is, users who cannot see the screen will not understand.
• An audio description would clarify: "Click Settings on the top toolbar."

Examples¶

Pass examples¶

• A video with an audio description track
  Include a separate narration to describe important visual elements.

<video controls>
  <source src="video-with-audio-description.mp4" type="video/mp4">
  <track kind="descriptions" src="audio-description.vtt" srclang="en" label="Audio Description">
</video>

• A separate version of the video with audio descriptions is available
  If it is not possible to add an audio description track, provide an alternate version.

<p>Watch the <a href="video-with-audio-description.mp4">accessible version with audio descriptions</a>.</p>

• Visual information is already included in the narration
  If all important actions and visuals are naturally described in the dialogue, an additional audio description may not be necessary.

Fail examples¶

• No audio description for important visuals
  A silent instructional video that relies on on-screen text and actions without a voiceover.

• Only captions provided, no audio description
  Captions transcribe speech but do not describe visual actions, which can still leave blind users without key information.

Affected users¶

This check primarily benefits:

• Blind and visually impaired users who cannot see visual elements in videos.
• Users with cognitive disabilities who may benefit from verbal reinforcement of visual content.

How¶

This section provides instructions about how to review a video for an audio description.

When this check flags a video, follow these steps:

1. Play the video with only the sound.
   • Play the video and listen to the dialog without the video.
   • Ask yourself: Can I fully understand the content without the visuals?
2. Check for an audio description track.
   • Right-click the video and determine if there is an Audio Description track.
   • If there is an audio description track, play it and verify that it describes key visuals.
3. Check if important visuals are already in the dialogue.
   If the video narration already describes all of the necessary visuals, an additional audio description may not be required.

How to fix it¶

This section provides a few suggestions about how you can correct the issue.

• Add an audio description track
  Include an audio description track in your <video> element:

<video controls>
  <source src="video.mp4" type="video/mp4">
  <track kind="descriptions" src="audio-description.vtt" srclang="en" label="Audio Description">
</video>

• Provide an alternative version
  If it is not possible to add an audio track, provide a separate version with audio descriptions:

<p>Watch the <a href="video-with-audio-description.mp4">accessible version with audio descriptions</a>.</p>

• Use a narrator to describe visuals during the video
  When you create a new video, include descriptions of key actions within the main narration so that you do not have to rely on a separate audio description track.

Additional resources¶

WCAG success criteria

1.2.5 Audio Description (Prerecorded)