Volcengine Video Lip Sync: AI Video Editor

Sync any video's lips to a new audio track with Volcengine Lip Sync. Supports scene detection and vocal separation. Try free — pay per generation.

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Overview

About this model

Volcengine Video Lip Sync re-times the mouth movements in an existing video to match a new target audio track, producing a natural-looking dubbed or re-voiced result. It supports a fast lite mode tuned for single-person frontal footage and a basic mode that adds scene segmentation and speaker identification for more complex, multi-shot scenes. The output is returned as an MP4 at 25fps, with its duration following the audio track — trimming the video if it runs longer than the audio, or looping it if shorter. Optional vocal separation strips background noise from the driving audio before it's applied.

1Localization: Redub existing footage into a new language while keeping the original visuals.
2Content repurposing: Swap in a new voiceover or script for an existing talking-head video without reshooting.
3Marketing: Update ad or product videos with fresh audio messaging in bulk.
4Podcasting to video: Add synced lip movement to video clips paired with a separately recorded voice track.
5Accessibility: Produce audio-matched video versions for multilingual audiences.
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Pricing & Value

Cost analysis

muapiapp$0.06/sec of audio (1.3× margin applied)

Pay-per-generation, no subscription required.

Fal.aiNot available

Fal.ai does not offer this specific model.

ReplicateNot available

Replicate does not offer this specific model.

* Competitor pricing is estimated based on similar model architectures and usage tiers.

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Technical Details

Configuration schema

ModeEnum (2 options)

Service mode. 'lite' is for single-person frontal videos with faster processing. 'basic' is for single-person complex scenes, supporting scene segmentation and speaker identification.

Default Valuelite
Video URLstring

Video URL. Supported resolution: 360p-1080p. Videos above 1080p are compressed to 1080p; below 360p is not supported. Supported formats: MOV, MP4, HDR. Max file size: 500MB.

Default Valuehttps://d3adwkbyhxyrtq.cloudfront.net/muapi/data/volcengine-lipsync-video.mp4
Audio URLstring

Target pure vocal audio URL used to drive the video's lip movements. Max file size: 10MB.

Default Valuehttps://d3adwkbyhxyrtq.cloudfront.net/muapi/data/volcengine-lipsync-audio.mp3
Separate Vocalboolean

Enable vocal separation to suppress background noise.

Default Valuefalse
Scene Detectionboolean

Enable scene segmentation and speaker identification. Only supported in Basic mode.

Default Valuefalse
Align Audio (Loop Video)boolean

Supported in Lite mode. Whether to loop the video when the audio is longer than the video.

Default Valuetrue
Align Audio Reverseboolean

Supported in Lite mode. Whether to loop the video in reverse (backward). Requires align_audio to be true.

Default Valuefalse
Template Start Secondsint

Supported in Lite mode. Start time of the template video, in seconds.

Default Value0
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Implementation Guide

Developer documentation

How to Use Volcengine Video Lip Sync

  1. Prepare your inputs: Upload a source video (360p–1080p, MOV/MP4/HDR, up to 500MB) and a clean vocal audio track (MP3, WAV, AAC, or OGG, up to 10MB) that will drive the lip movements.

  2. Pick a mode: Use mode: "lite" for a single-person frontal video for faster processing, or mode: "basic" for more complex scenes with multiple shots or speakers (enables open_scenedet).

  3. Tune alignment (lite mode): If your audio is longer than the video, align_audio (default true) loops the video to match; align_audio_reverse loops it backward instead. templ_start_seconds sets where in the video the template starts.

  4. Submit and poll: Call the endpoint below, then poll the task-detail endpoint (or use callBackUrl) until the job completes.

curl -X POST https://api.muapi.ai/api/v1/volcengine-video-to-video-lip-sync \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "mode": "lite",
    "video_url": "https://your-domain.com/video/example.mp4",
    "audio_url": "https://your-domain.com/audio/speech.mp3",
    "separate_vocal": false
  }'

Common Questions

Frequently asked

What does Volcengine Video Lip Sync do?

It takes an existing video and a target audio track, then regenerates the speaker's mouth movements so they match the new audio — useful for dubbing or re-voicing footage without reshooting.

What's the difference between lite and basic mode?

`lite` mode is optimized for single-person, frontal-facing videos and processes faster. `basic` mode supports more complex scenes, including scene segmentation and speaker identification via `open_scenedet`.

What video and audio formats are supported?

Video: MOV, MP4, or HDR, 360p–1080p resolution (above 1080p is compressed down), up to 500MB, 24–60fps, 1–30 Mbps bitrate. Audio: MP3, WAV, AAC, MP4-audio, or OGG, up to 10MB.

What happens if the audio is longer or shorter than the video?

The output duration always follows the audio. If the video is shorter than the audio, it's looped (`align_audio`) — optionally in reverse (`align_audio_reverse`) — to fill the gap. If the video is longer, it's trimmed to the audio length.

What does separate_vocal do?

When enabled, it runs vocal separation on the input audio to suppress background music or noise before using it to drive lip movement, improving sync accuracy on noisy tracks.

What resolution and frame rate is the output video?

The generated video is returned as MP4 at 25fps, matching the input video's resolution up to 1080p.