2K AI video generator API: MiniMax H3 at 2K on Sume

To generate 2K video by API on Sume, send POST /v1/videos with model: "minimax-h3" and resolution: "2K". MiniMax's announcement describes H3 as generating up to 15 seconds at 2K; Sume's docs describe its 2K and 4K as priced upscales of the native 768p output.

Vendor facts are from MiniMax's announcement and model card, and Sume facts from the Video generation docs and pricing code, read 2026-09-29.

How do I ask for 2K?

Set resolution to 2K on minimax-h3. It does not appear in the model's supported_resolutions, so do not depend on that list to find it. minimax-h3-max does not accept 2K or 4K in current code.

curl -X POST https://api.sume.com/v1/videos \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: h3-2k-001" \
  -d '{
    "model": "minimax-h3",
    "prompt": "A slow dolly along a rain-lit market street at night, neon signs reflecting on wet stone",
    "resolution": "2K",
    "aspect_ratio": "16:9",
    "duration": 8
  }'

What does a 2K clip cost?

Per output second by resolution, reserved on submit at the provider list × 1.25, plus the 5.5% agent fee by default.

Is Sume's 2K the same pipeline MiniMax describes?

MiniMax's model card describes a 2K step, H3-Regenerate-2K, which the card lists as an upscaling module that reuses context from the 768p base. Sume's docs say only that 2K and 4K are upscales of native 768p that are priced if requested; they do not say which provider step runs, so this post does not claim one.

What are the length and ratio limits?

5–15 seconds in whole seconds, and aspect ratios 21:9, 16:9, 4:3, 1:1, 3:4 and 9:16. For anything that is not 2K, remember that 720p is refused on H3: use 768p.