Lip sync

What is Lip sync?

Lip sync is the alignment of visible mouth movements in a video with the spoken audio, so the two appear to originate from the same person at the same moment. In short-form video, AI lip sync is commonly used when dubbing content into another language, adjusting the speaker's mouth movements to match the new audio track.

When you'd use it

1. 1When dubbed audio in another language needs to match the visible mouth movements of the original speaker.
2. 2When an AI avatar's speech needs to look natural against its generated face.
3. 3When a voiceover was re-recorded and the new timing no longer matches the footage.
4. 4When an on-screen character or presenter has visible speech that does not align with the audio track.

Example

A creator records a tutorial in English, then AI dubbing software re-voices it in Spanish and adjusts the mouth movements frame by frame. On medium shots the result is indistinguishable from native recording, though close-ups of mouth movement show slight warping.

Use cases

1. 1Aligning translated voiceover to a speaker's mouth movements for a localized product video.
2. 2Matching synthetic speech to an AI avatar's face in a generated presenter clip.
3. 3Correcting audio drift in a re-recorded narration track over existing talking-head footage.

FAQ

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