Define the required visible-message interval
Synthetic sound-off placement requires visible text for the whole spoken message 0–10 seconds. Caption spans are 0–4 and 6–10, start included/end excluded. They contain the correct words in their own spans; no other text covers 4–6. This is a local communication condition.
| Span | Seconds | Coverage |
|---|---|---|
| 0–4 | 4 | Captioned |
| 4–6 | 2 | Missing |
| 6–10 | 4 | Captioned |
Union the caption spans
- Read required 0–10 interval
- Merge existing caption spans
- Locate 4–6 gap
- Request missing text/timing and recheck
A caption file existing does not prove continuous visible coverage.
What fraction of required time is captioned?
Show the worked answer
8/10=80%; two seconds are missing. The correction request names 4–6, not a generic request to add captions.
Request the uncovered range
| Case | Decision or result | Reason |
|---|---|---|
| Count two caption blocks | Insufficient | Time gap remains |
| Fill 4–6 with matching text | Can complete coverage | All 10sec visible |
Verify actual visible timing in the rendition, including the gap edges. File receipt alone cannot close the uncovered-message task.