Sora thumbnail and spritesheet variants: use Sume video frames

Sume has no thumbnail or spritesheet endpoint, but POST /v1/video-frames rebuilds both. Name times with at[] for a thumbnail, or set fps for a contact sheet's worth of stills, and you get durable image artifacts back.

Sora's guide said each completed video had a thumbnail and a sprite sheet, selected by variant on the content download. It also says the Sora 2 models and Videos API shut down on September 24, 2026. Sume facts are from Video frames; read 2026-09-30.

What did the Sora variants return?

The guide shows variant=thumbnail saving a .webp and variant=spritesheet saving a .jpg; the default is variant=video for the MP4. It describes them as lightweight assets for previews, scrubbers or catalog displays.

How do I get a thumbnail on Sume?

Video frames takes one workspace media.sume.com clip plus a program. Import the clip first with POST /v1/media-imports; off-host URLs are rejected. Then ask for a time, for example "at": [0]. The docs allow 1-24 values, each at least 0 and inside the clip's duration. format is jpeg (default) or png, and max_edge (16-2160) clamps the long edge.

curl -X POST https://api.sume.com/v1/video-frames \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -H "Idempotency-Key: thumb-001" \
  -d '{
    "video_url": "https://media.sume.com/artifacts/artf_demo/talk.mp4",
    "at": [0, 2.5],
    "max_edge": 480
  }'

How do I get a sprite-sheet equivalent?

Use fps instead of at[] (send exactly one). It must satisfy 0 < fps <= 2, samples land at the middle of each time bin, and the result is capped at 24 frames. Sume returns separate images, not a packed sheet, so tile them yourself if you need one image.

What changes from the Sora flow?

Where can I read more?

The general walkthrough is extract video frames with the API; picking a Shorts thumbnail shows the max_edge choice.