Festival lineup reel at 9:16: Seedance 2.5, 12 s, audio reference

Use Seedance 2.5 at 9:16 and send the festival's own track as an audio reference. A 12-second clip is $6.94 at 720p and $3.23 at 480p on Sume. Audio references are not priced separately; only a reference video changes the bill, to $9.37 at 720p for the same 12 seconds.

Why Seedance 2.5 for this

A lineup teaser is cut to music. Of the four models in this cluster, Seedance 2.5 is the one built around audio-and-video references: fal's explainer, read 2026-10-08, describes a reference endpoint taking up to 30 images, 10 videos and 10 audio files, with about 30 seconds in each of the video and audio pools. Sume's catalog lists reference audio for Seedance 2.5, 4 to 30 seconds, and 9:16 among eight aspect-ratio values.

Make sure you hold the rights to the track, and to the artwork you send as image references. A reference does not clear anything for you.

Prices at 9:16

Sume bills the provider list price times 1.25, rounded up to the cent per job.

Keeping text off the model

Artist names are the content, so do not leave them to the generator.

• Generate mood footage per headliner from their press photos with permission, then add names in your editor.
• Draft the 12 seconds at 480p ($3.23) to check the cut against the track.
• Send one 12-second audio excerpt, not the full song.
• Render separate 9:16 and 16:9 jobs; do not crop one to fit the other.

Submit it and read the result

Sume reserves the billable amount from your workspace USD balance when the job is submitted, then returns a polling_url. Add the track as an audio_url entry in input_references once the draft prompt is right. Poll the job until status is completed or failed; a completed job lists its files in unsigned_urls.

import os
import time
import requests

H = {"Authorization": f"Bearer {os.environ['SUME_API_KEY']}"}
body = {
    "model": "seedance-2.5",
    "prompt": "A slow push-in on the scene, soft natural light",
    "duration": 12,
    "resolution": "480p",
    "aspect_ratio": "9:16",
}
r = requests.post("https://api.sume.com/v1/videos", headers=H, json=body, timeout=60)
r.raise_for_status()
url = r.json()["polling_url"]
while True:
    job = requests.get(url, headers=H, timeout=30).json()
    if job["status"] in ("completed", "failed"):
        break
    time.sleep(10)
print(job["status"], job.get("unsigned_urls"))

Limits

fal's page lists 480p and 720p for Seedance 2.5; Sume's catalog also lists 1080p, and the 1080p column follows the catalog. I did not test how closely the output follows a beat in a reference track. Run a 480p draft first and judge it by ear.