90-second AI video API: three 30 s Wan 3.0 jobs and what they cost

A 90-second AI video on Sume is three 30-second jobs, the largest chunk any model accepts. On Wan 3.0 the three jobs cost $5.64 at 480p, $11.25 at 720p and $22.50 at 1080p.

Each job is a separate POST /v1/videos request and a separate file, so the piece becomes a short shot list of three scenes joined in an editor.

What does a 90-second piece cost?

Wan 3.0 bills $0.0625, $0.125 and $0.25 per second at 480p, 720p and 1080p after Sume's 1.25 multiplier. Jobs are rounded up to the cent individually.

How should you plan three scenes?

Write the 90 seconds as three scenes with one clear change between each, and give each job one scene. A scene boundary hides the seam, which a mid-action cut cannot do. Keep the subject the same with shared input_references, and keep the aspect ratio and resolution fixed.

• Scene 1 sets place and character.
• Scene 2 starts from scene 1's last frame via frame_images, then moves the action on.
• Scene 3 closes the piece with a still beat that is easy to cut to a title.

Does audio match across the three files?

Not automatically. Each job generates its own sound, so ambient audio may jump at the join. If the piece needs a single track, mute the clips and lay one soundtrack over the joined file. Sume's video router lets you pass generate_audio per request on models that support it.

What does the loop look like?

A small script submits the three scenes with idempotency keys.

import os, requests

H = {"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"}
scenes = [
    "A fisherman prepares his boat at first light",
    "The boat leaves the harbour into mist",
    "The boat returns at sunset, gulls overhead",
]
for i, scene in enumerate(scenes, 1):
    r = requests.post(
        "https://api.sume.com/v1/videos",
        headers={**H, "Idempotency-Key": f"doc-90-{i}"},
        json={"model": "wan-3.0", "prompt": scene, "duration": 30,
              "resolution": "720p", "aspect_ratio": "16:9"},
    )
    r.raise_for_status()
    print(i, r.json()["id"])

Where do you save money?

Draft each scene at 480p for 5 seconds ($0.32 each, $0.96 for three) before spending $11.25 at 720p. A reroll of one 30-second scene at 720p costs $3.75, so replace single scenes rather than the whole piece.