Birthday party invitation video: a 5-second Wan 3.0 clip from a photo

A 5-second birthday invitation clip from one photo is a wan-3.0 job with the photo as first_frame, duration: 5 and aspect_ratio: "9:16". On Sume it costs $0.3125 at 480p, $0.625 at 720p and $1.25 at 1080p, because Wan 3.0 is billed per second by resolution (list $0.05, $0.10 and $0.20 per second times 1.25), per the Video Router table read 2026-10-05.

Wan 3.0 accepts 2 to 30 seconds, so a 5-second clip is well inside its range, and it takes first_frame and last_frame images.

What do I send?

Post the child's party photo (or the party-hat illustration) as a first frame and put the motion in the prompt. Leave the date, time and address out of the prompt: generated video text is unreliable, so overlay them in your invite tool.

curl -X POST https://api.sume.com/v1/videos \
  -H "Authorization: Bearer $SUME_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"wan-3.0","prompt":"Confetti drifts down, balloons sway, the camera pushes in slowly","duration":5,"resolution":"720p","aspect_ratio":"9:16","frame_images":[{"type":"image_url","image_url":{"url":"https://example.com/party.jpg"},"frame_type":"first_frame"}]}'

Which resolution is enough for a phone invite?

Invitations are watched on a phone and sent through chat apps, so 480p or 720p is usually plenty and costs half or a quarter of 1080p. Draft at 480p, then re-run the keeper at 720p.

How do I poll and download the result?

A submit returns 202 with id, polling_url, status and model. Poll GET /v1/videos/{id} until status is completed (the other terminal values are failed and cancelled), then download from GET /v1/videos/{id}/content?index=0 with the same bearer key. Wan 3.0 clips can carry native audio; the Video Router catalog lists audio as supported for this id.

curl https://api.sume.com/v1/videos/JOB_ID -H "Authorization: Bearer $SUME_API_KEY"
curl -L "https://api.sume.com/v1/videos/JOB_ID/content?index=0" \
  -H "Authorization: Bearer $SUME_API_KEY" --output clip.mp4

Can I send the clip as a message to guests?

Download the MP4 and share it through your messaging app. If a recipient's app wants a smaller file, the video filter tool can scale it down.