What extended audio description changes
Standard AD fits narration into the existing timeline. Extended AD temporarily pauses the video so a necessary description can finish, then resumes from the same point. The final described version may be longer than the original.
The approach is useful for fast tutorials, title-heavy ads, visual explainers, and dialogue-dense scenes where a key action or text has no safe opening.
When a pause is justified
- A name, role, warning, instruction, or call to action appears during speech and is never said aloud.
- A demonstration moves to the next step before it can be described.
- A visual event changes the meaning of the dialogue.
- A rapid title sequence carries essential context.
Ordinary setting detail should not repeatedly stop a speaker. Use the strongest natural gap, shorten the line, or omit low-value detail.
How to build a good pause
- Anchor the cue to the frame where the information becomes clear.
- Pause both picture and original program audio.
- Speak the concise description without competing dialogue.
- Resume the original video and audio at the exact source timestamp.
- Map captions to the original source clock, not the added narration clock.
Publishing choices
A separate described MP4 can carry the pauses directly and works anywhere a second video can be offered. A separate audio track needs a player that understands the extended timeline and can pause the original video in sync. Test seeking, resuming, captions, keyboard controls, and mobile playback.
The W3C explains this pattern in Technique G8. VoxDescribe can create synchronized pauses and export a described video plus separate audio tracks. Review the output options.