Audio Description or Media Alternative (Prerecorded)
Summary:
WCAG 1.2.3, "Audio Description or Media Alternative (Prerecorded)," aims to make prerecorded video content accessible to blind or visually impaired users. This is done by providing audio descriptions of visual information or an alternative media format like a text transcript.
What:
The guideline requires that an audio description or a full-text alternative for all prerecorded video content is provided. The audio description narrates key visual details that are not conveyed through the original audio, while the text alternative describes both audio and visual content.
Why:
This ensures that users who cannot see the screen can still understand the content in videos. Audio descriptions fill in the gaps for visual elements, while text alternatives provide a comprehensive overview of both audio and visual content.
Examples and Scenarios:
- Educational Videos: Providing audio descriptions of on-screen graphics or actions.
- Corporate Presentations: Including a text transcript detailing both spoken words and visual elements like charts or slides.
- Entertainment Videos: Offering audio descriptions for key visual scenes not explained by the dialogue.
How to Comply:
- Websites: Add audio descriptions to videos or provide a text transcript that includes descriptions of both the audio and visual content.
- Mobile Apps: Ensure video content within the app comes with audio descriptions or has a linked text transcript.
- Software Applications: Similar to websites, include audio descriptions or provide text alternatives for any prerecorded videos in the application.
Exceptions:
- Alternatives Available: If the information in the video is fully explained in the main audio or if an alternative format like a text transcript is available elsewhere, additional audio descriptions may not be necessary.
- Purely Decorative Content: Videos that serve a purely decorative purpose and do not provide important information might not require audio descriptions.