TikTok API accepts MP4, WebM or MOV: which format Sume returns

Sume's trim and timeline jobs return an MP4, and TikTok's media transfer guide lists "MP4 (recommended), WebM, MOV" as supported formats, so no conversion step is needed for the container. The guide text quoted here lists no codec, so this post makes no codec claim about TikTok.

What does each side say?

Only formats and one size are compared, because those are the numbers both pages give.

Which Sume jobs write an MP4?

Video trim returns "a new MP4 artifact", and Timeline 1.0 returns "one MP4". Trim's exact precision re-encodes with libx264 in yuv420p and remuxes kept audio as AAC. With keyframe it copies the stream instead, so the codec stays whatever the source used.

What if my generated clip is not an MP4?

Run it through Timeline 1.0 or an exact trim, which write MP4. A video-inspect probe (free with frames: false) shows what a file contains before you decide.

curl -X POST https://api.sume.com/v1/video-trim \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: to-mp4-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/source.mp4",
    "start": 0,
    "duration": 30,
    "precision": "exact"
  }'

What should I still check?

Read the result's duration_seconds and check the length against the creator's allowed maximum on TikTok. Also check the size against the 4GB maximum on the file itself, since Sume states none. Sume does not post to TikTok; the upload call is yours.

Should I use keyframe or exact precision?

Use exact when the source's codec is unknown or unusual, because the output is then a known H.264 MP4 in yuv420p. Use keyframe only when you accept that the cut may start a GOP early and that the stream is copied unchanged. The result reports actual_start_seconds so you can see where a keyframe cut really began.

For joining clips, Timeline 1.0 takes an audio spine of 1 to 1800 seconds and up to 200 video slots and writes one MP4, priced at $0.10 per output minute.

• exact: frame-accurate re-encode, libx264, yuv420p.
• keyframe: stream copy, cut may start a GOP early.
• Both write a new MP4 artifact and leave the source alone.
• Neither takes codec, crf or preset; those are refused.