Symphony Creative Studio reference clips must be under 10 seconds

TikTok's Symphony Creative Studio help page says reference videos must be under 10 seconds (read 2026-10-02). If your best clip is longer, cut it to the moment you want to copy before you upload. Sume's video trim does that for $0.02 per job, according to its docs.

What the help page lists

The page describes three modes: text to video, image to video and reference to video. It says Dreamina Seedance 2.0 restricts some capabilities, including reference images or videos with real faces and celebrity likenesses (read 2026-10-02).

Trim a reference clip with Sume

Sume's video trim takes one workspace clip plus a start and exactly one of end or duration, and returns a new MP4. The source is untouched. The clip must already live on media.sume.com, so import it first; a write needs an Idempotency-Key.

• Pick the 6 to 8 seconds that show one scene and one action.
• Trim with start and duration, and read actual_start_seconds in the result.
• Download the new MP4 and upload it as the Symphony reference.
• Check there is no split-screen layout or real face before you submit.

Limits

Trim only cuts time. It does not remove a real face, split a multi-scene clip into one scene or change layout. If the source has a split-screen design, crop to one panel with video filter, which supports crop operations and an unbilled check endpoint, or choose another clip.