| name | check-audio-sync |
| category | media |
| description | Check audio-to-picture sync at multiple points and identify offset, drift, variable-rate, clock, or routing causes. Use when dialogue, music, effects, or remote recordings do not align reliably with video. |
check-audio-sync
Check the beginning, middle, and end before applying one offset.
When to use
- Use after ingest, multicamera sync, transcode, remote recording, long takes, or export.
- Preserve original timestamps, rates, and files before resampling or changing interpretation.
Procedure
- Record source devices, timecode, frame rates, sample rates, variable-rate status, duration, and timeline settings.
- Find a sharp visible and audible event near the start and measure offset.
- Repeat at the middle and end to distinguish constant offset from progressive drift or discontinuity.
- Compare camera scratch, recorder, remote local, platform, and reference tracks.
- Correct constant offset at the clip level; correct drift only after identifying clock, sample-rate, frame-rate, or dropped-media cause.
- Listen for phase, channel, pitch, edit, and time-stretch artifacts.
- Export a test and verify lip sync on target playback systems.
- Document corrections and retain the untouched source.
Done
- A sync report records sources, rates, measured points, offsets, drift, cause, correction, and untouched originals
- Timeline and exported playback checks verify lip sync, phase, pitch, continuity, and end-of-program stability