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Overview

Lip Sync matches new audio to lip movements in an existing video. For a still image and audio, use AI Talking Photo instead. Processing: See recent typical API-job times. Jobs run asynchronously, and duration varies with the input, selected settings, and queue load.

How It Works

  1. Provide a source video - Upload the video with the person speaking
  2. Provide audio - Upload the new audio track to sync to
  3. API processes the video - AI analyzes audio and animates lip movements
  4. Download the result - Retrieve your lip-synced video

Use Cases

For a complete voice-to-video workflow, follow the lip-sync starter recipe. It covers uploading your video and voiceover, submitting the lip-sync job, and downloading the result.
  • Dubbing and localization - Sync an existing translated audio track to the source video
  • Personalized messages - Create custom video messages with any voice
  • Educational content - Produce training videos with voiceovers
  • Entertainment - Create fun lip-sync content for social media
  • Accessibility - Add voiceovers to silent video content
For client localization projects, use the agency lip-sync pilot to compare matched clips, review outputs and track delivery cost.

Best Practices

Video Requirements

Clear, front-facing footage works best - Ensure the speaker’s face and lips are clearly visible throughout.
  • Face visibility - Full face visible with minimal obstructions
  • Good lighting - Even lighting on the face
  • Stable framing - Face stays in frame throughout
  • Moderate motion - Avoid extreme head movements
For standard and pro modes, the input video must show visible mouth movement in the opening seconds. A still portrait, including one saved as a static video, should use AI Talking Photo with the original image and your audio instead.

Audio Requirements

  • Clear speech - Well-recorded audio without background noise
  • Set start_seconds and end_seconds to select the clip and provide enough audio for that segment.
  • Supported formats - MP3, WAV, AAC, FLAC, M4A, OPUS, OGG/OGA, WEBM/WEBA, AIFF, AMR
  • Natural pacing - Normal speaking pace for best results

Matching Audio to Video

Code Examples

Basic Lip Sync

Pricing

Lip Sync is charged per rendered frame, and the rate depends on style.generation_mode: For example, a 10-second clip capped at 30 FPS in lite mode costs about 300 credits. Use max_fps_limit to lower the frame rate and reduce cost. Credits are only charged for the frames that actually render, and the completed job’s credits_charged shows the exact cost.
Try this in our Google Colab Cookbook: Run this API with sample code. Just add your API key.

API Reference

Lip Sync API Reference

View full API specification

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