TikTok 3-minute videos: cut a longer clip to 180 seconds via API

Cut to 180 seconds when you do not know the creator's tier: TikTok's guide says "All TikTok creators can post 3-minute videos," while only some can post 5-minute or 10-minute videos. POST /v1/video-trim with duration: 180 writes a new MP4 of that length.

Why choose 180 seconds?

It is the one length the page says every creator can post. Longer files depend on the creator's access, which the page does not let you read from a public number. If your workflow serves many accounts, 180 is the safe default and a longer cut is an opt-in.

How do I cut the right 180 seconds?

Pick the in-point with start, then set duration: 180. If you want the strongest moment and do not know it, extract stills with https://docs.sume.com/models/video-frames or run a video inspect first. Both read the clip without changing it.

curl -X POST https://api.sume.com/v1/video-trim \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: tiktok-180-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/long.mp4",
    "start": 12,
    "duration": 180
  }'

Does the cut keep sound and quality?

Sound is kept by default (audio: "keep"), remuxed as AAC on the exact path. Video is re-encoded with libx264 in yuv420p on exact; the docs give no bitrate or quality control, and encoder fields are refused as ffmpeg_fields_rejected. The price is $0.02 per job.

What are the limits?

The output must be 0.2 to 900 seconds and the source no longer than 1800. An end past the source clamps with a trim_clamped_to_source warning. Sume does not post to TikTok.

What if the story does not fit in 180 seconds?

Split it. Cut two or three trims with different start values and post them as a series, or assemble a tighter version from several moments with https://docs.sume.com/models/timeline. Trim keeps each piece as its own MP4, and every job needs its own Idempotency-Key so a retry cannot queue a duplicate.

• One trim per part, each at most 180 seconds.
• Give each part a different key, such as part-1 and part-2.
• Read duration_seconds from each result before posting.