Start a song at the chorus in a Short: split, then soundtrack

The Timeline soundtrack object takes a url, gain_db, loop, fade_out_seconds and duck_db, but no in-point. To start a track at the chorus, cut the chorus into its own file with Timeline audio split, then use that file's audio_url as the soundtrack. The split costs $0.01 per job. Read from the Sume docs on 2026-10-06.

How do I cut the chorus?

Import the track with POST /v1/media-imports, then call POST /v1/timeline-1.0/audio with operation: "split", the track url and one range. Omit end to run to the end of the file. The result is kind: timeline_audio with segments[], and each segment carries its own audio_url. Use the default wav format if you will join the clip again, or mp3 for a smaller file.

{
  "operation": "split",
  "url": "https://media.sume.com/artifacts/artf_demo/song.wav",
  "ranges": [{"start": 62.5, "end": 92.5}]
}

How do I wire it into the Short?

Poll GET /v1/jobs/:id/result for the split, copy segments[0].audio_url and set it as soundtrack.url in a render with audio.mode: "silence" and a matching duration_seconds of 30. Add a fade_out_seconds so the ending is not clipped.

What does the two-step cost?

The split is $0.01 and a 30-second render is $0.10, so $0.11 per Short before any caption job. Rights to the music are yours to confirm: Sume cuts the file you import, it does not license it.