WebApp Guides

Speaker Selection — Studio

Speaker selection lets you pick which person gets lipsynced in a video or image with multiple people. You can manually click a face, or for videos, 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, lipsync-2-pro, and sync-3 models in both Lite and Advanced modes. Note that react-1 does not currently support this feature. For sync-3 image inputs, only manual face selection is supported — Active Speaker Detection is video-only.

Selecting a Speaker in Video

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.

Selecting a Speaker in Images (sync-3)

For images with multiple faces, you can select which person to lipsync using the same face detection overlay.

1

Upload your image

Upload an image with the sync-3 model selected. Face detection runs automatically when the image loads.

2

Click on the speaker's face

If multiple faces are detected, click on the face you want to lipsync. The selected face gets a bright green border and appears in the controls.

3

Generate

Click the Sync Labs button. The speaker coordinates are sent with your generation request.

Active Speaker Detection is not available for image inputs — only manual face selection. If your image contains a single face, the system skips the selection step automatically.

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