Glossary · AI Video
Quick answer
AI lip sync is technology that matches a person’s mouth movements in a video to a given audio track, so the subject appears to genuinely speak the words. It powers talking avatars, dubbed and translated videos, and photo-to-speech tools. Good lip sync aligns not just lip shapes but timing, jaw movement, and facial expression with the audio.
Lip-sync models analyze the phonemes in an audio track — the individual speech sounds — and generate the corresponding mouth shapes (visemes) frame by frame, blending them naturally into the existing face.
The technique is central to two workflows: making a still photo speak (avatar videos) and re-voicing existing footage, such as translating a video into another language while keeping the speaker’s face believable.
In VdoBloom, lip sync underpins the AI avatar and spokesperson tools, where a photo plus a script becomes a speaking video.
VdoBloom starts you with 10 free credits — enough to put this into practice with no card required.
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