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On this page
  • Selecting a Speaker
  • Changing or Clearing Your Selection
  • Active Speaker Detection
  • Related Resources
WebApp Guides

Speaker Selection — Studio

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Last updated May 15, 2026

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Speaker selection lets you pick which person gets lipsynced in a video with multiple people. You can manually click a face or use Active Speaker Detection to let Sync Labs identify the speaker automatically. For programmatic usage via the API, see the API guide.

Speaker selection is available with our lipsync-2 and lipsync-2-pro models in both Lite and Advanced modes. Note that react-1 does not currently support this feature.

Selecting a Speaker

1

Upload your video

Upload a video that contains multiple people. Sync Labs detects the number of speakers in the background.

Studio overview

2

Enable face detection

Click the icon in the video player controls. Green bounding boxes appear around detected faces with a hint: “select which speaker to lipsync.”

Face detection active

3

Click on the speaker's face

Click on the bounding box of the person you want to lipsync. The selected face gets a bright green border and a face thumbnail appears in the controls.

Face selected

4

Generate

Click the Sync Labs button. The speaker configuration is sent automatically with your generation request.

Changing or Clearing Your Selection

  • Click the X on the face thumbnail to clear your selection.
  • Scrubbing through the video re-runs detection.
  • Click another face to switch speakers.

Active Speaker Detection

As an alternative to manual selection, toggle Active Speaker Detection in the Studio settings panel. Sync Labs identifies the speaker via lip movement analysis — no manual click needed.

Manual selection and Active Speaker Detection are mutually exclusive — you can only use one at a time. Active Speaker Detection may not work reliably on silent or low-motion clips.

Related Resources

  • Lipsync Model — learn about supported models including lipsync-2 and lipsync-2-pro
  • Quickstart — get started with your first Sync Labs generation