Let's continue our journey into WCAG 2.1 Success Criteria, today focusing on Success Criterion 1.2.7: Extended Audio Description (Prerecorded). This is a Level AAA requirement, representing the highest level of accessibility, and applies to prerecorded video content in synchronized media.
As stated in the official W3C documentation for WCAG 2.1 (section 1.2.7):
"Success Criterion 1.2.7 Extended Audio Description (Prerecorded) (Level AAA)
Where pauses in foreground audio are insufficient to allow audio descriptions to convey the sense of the video, extended audio description is provided for all prerecorded video content in synchronized media."
What does Criterion 1.2.7 mean in practice?
This criterion requires a significant commitment to ensure all important visual information in a prerecorded video is accessible to blind or low-vision individuals. Specifically:
- Applies to: All prerecorded video content that is part of synchronized media (i.e., video with a significant audio track, such as films, documentaries, tutorials).
- Trigger Condition: The requirement is triggered when the natural pauses in the video's audio (dialogue, music, background sounds) are insufficient to insert a complete and understandable audio description of everything visually happening that is essential to grasping the "sense of the video."
- The Required Solution: In these situations, extended audio description must be provided. "Extended" means that the video playback is temporarily paused to allow the full descriptive narration of all essential visual elements to play out. This implies that the version of the video with extended audio description will be longer than the original.
Level AAA signifies the highest level of accessibility. This criterion is classified as AAA for several reasons:
1. Complexity and Cost: Producing an extended audio description that alters the timing of a video requires substantial scripting, recording, editing, and post-production work. It often involves creating an entirely new version of the media.
2. Impact on Pacing: Pausing the video for description alters the original pacing and timing of the content, which might not be acceptable for all contexts or types of media (e.g., visual art pieces, music).
Despite the challenges, achieving this level of conformance ensures that blind or low-vision individuals can access all crucial visual information, without loss due to time constraints, providing an extremely rich and complete user experience.
How is Criterion 1.2.7 implemented?
1. In-depth Analysis: Carefully identify every single crucial visual information — scenes, actions, expressions, on-screen text, graphs, and any other visual element — that contributes to the video's meaning and is not already explained by the original dialogue or audio.
2. Pause Evaluation: Determine if the natural pauses within the video are sufficient to insert concise audio descriptions of these visual cues.
3. Extended Script Creation: If pauses are insufficient, create a detailed audio description script that covers all missing information, without concern for its length.
4. Recording and Editing: Record the audio description and integrate it into the video, inserting necessary pauses in the video playback to accommodate the extended narration.
5. Offering the Alternative: It is crucial that users can easily choose between the standard video version and the version with extended audio description.
Criterion 1.2.7 exemplifies WCAG's commitment to full inclusion, pushing developers to overcome time-based media limitations to ensure universal access to visual information.
We invite the community to share their experiences:
- Have you ever needed to implement Criterion 1.2.7 (Extended Audio Description for Level AAA)? What tools or workflows did you find most effective?
- What are the biggest challenges in producing extended audio descriptions that require pausing the video?
- Can you share examples of media that have successfully implemented this criterion, offering an AAA experience?
Warm regards,
Michele (wcgadmfrm)
WCAG Plus Forum Team