WCAG (Level AA) SC 1.2.5 Audio Description (Prerecorded) (w3.org)
Issue description
WCAG 1.2.5, “Audio Description (Prerecorded)” aims to make video content accessible to people who are blind or have low vision. It requires that prerecorded video content in synchronized media, like videos on your website or in online courses, include audio descriptions. Here’s why this is important:
- Visual information is inaccessible: People who are blind or have low vision cannot perceive the visual elements of a video, such as actions, characters, scene changes, and on-screen text.
- Audio descriptions provide context: Audio descriptions provide a narrated explanation of these visual elements, allowing users with visual impairments to understand what is happening in the video.
Without audio descriptions, these users miss out on crucial information and cannot fully comprehend the video content. This guideline ensures that everyone, regardless of their visual abilities, can access and understand video content, promoting inclusivity and equal access to information.
Related requirements
The following WCAG source criteria are often related to this as well. They can provide additional insights into specific challenges you may be encountering.
- WCAG (Level A) SC 1.2.3 Audio Description or Media Alternative (Prerecorded)
- WCAG (Level AA) SC 1.2.4 Captions (Live)
- WCAG (Level AAA) SC 1.2.6 Sign Language (Prerecorded)
- WCAG (Level AAA) SC 1.2.7 Extended Audio Description (Prerecorded)
- WCAG (Level AAA) SC 1.2.8 Media Alternative (Prerecorded)
- WCAG (Level AAA) SC 1.2.9 Audio-only (Live)
Who this issue impacts
Follow the links for additional information on user impairments:
Suggestions for remediation
Remediating WCAG 1.2.5, “Audio Description (Prerecorded)” involves providing audio descriptions for your videos to make them accessible to people who are blind or have low vision. Here’s a breakdown of how to do it:
Create audio descriptions
- Describe the visuals: Write concise and objective descriptions of the important visual elements in the video, including:
- Actions and events
- Characters and their appearance
- Scene changes and settings
- Body language and facial expressions
- On-screen text and graphics
- Synchronization: Ensure the audio descriptions are synchronized with the video, fitting naturally within pauses in dialogue or other audio.
- Clarity: Use clear and concise language, avoiding jargon or overly descriptive language.
Implementation options
- Separate audio track: Create a separate audio track containing the audio descriptions that users can choose to enable. This is often preferred as it doesn’t interfere with the original audio for those who don’t need it.
- Integrated audio descriptions: Incorporate the audio descriptions directly into the main audio track during natural pauses in the dialogue. This can be simpler for basic videos but may be less flexible for users.
Tools and resources
- YouDescribe: A free web-based tool that allows you to create and share audio descriptions for YouTube videos (YouDescribe.org).
- VoiceOver (macOS) and Narrator (Windows): Built-in screen readers that can read audio descriptions if they are present in the video file.
- Professional audio description services: Several companies and freelancers offer professional audio description creation services.
Technical considerations
- Video players: Use media players that support audio descriptions.
- Metadata: Include metadata in your video files to indicate the presence of audio descriptions.
Example
Here’s how audio description would make a scene about a pride of lions accessible:
Visuals: The video shows a wide shot of the African savanna. The sun is setting, casting long shadows. A pride of lions is gathered around a watering hole.
Audio Description: “The sun dips below the horizon, painting the vast African savanna in shades of orange and purple. A pride of lions, about ten in number, gathers around a small watering hole. Dust motes dance in the golden light.”
Visuals: A lioness approaches the water and takes a long drink. Cubs playfully bat at each other near her.
Audio Description: “A lioness with a dark mane cautiously approaches the water’s edge. She lowers her head and laps at the water, her reflection rippling on the surface. Nearby, two cubs playfully swat at each other with their paws, tumbling in the dust.”
Visuals: Suddenly, a zebra appears in the distance. The lions tense up and look alert.
Audio Description: “Suddenly, a lone zebra with black and white stripes emerges from the tall grass in the distance. The lions instantly become alert, their ears pricked and their eyes fixed on the potential prey.”
Visuals: The lionesses start to stalk the zebra, moving slowly and quietly through the grass.
Audio Description: “Several lionesses begin to stalk the zebra. They crouch low to the ground, their bodies blending with the tall grass as they move with stealth and precision.”
Visuals: The zebra senses danger and runs away. The lions give chase.
Audio Description: “The zebra senses the approaching danger and bolts, its hooves pounding the dry earth. The lionesses erupt in a burst of speed, chasing after the fleeing zebra.”
This audio description allows a person who is blind or has low vision to visualize the scene, understand the lions’ actions, and experience the stress of the hunt. It brings the visual elements to life through detailed narration.
