Advent calendar video series: 24 doors, one teaser, one bulk run

An advent calendar video series has 24 doors starting on Tuesday 1 December 2026. Two ways to build it on Sume: a 48-second teaser of all 24 doors from 24 stills for about $1.43, or 24 separate daily 4-second clips for about $3.73. Pick the teaser first, since it also works as the announcement.

Facts are from Wikipedia's Advent calendar article, read 2026-10-03: the calendar counts the days of Advent before Christmas; traditional ones have a door for each day up to 24 December; many reusable ones start on 1 December while others start on the first Sunday of Advent; it began with German Lutherans; and behind each door is an image, a poem, part of a religious story or a small gift. Our Hanukkah eight-night post covers the shorter sibling.

Decide what is behind each door

The doors are the content. A bakery can show a different biscuit; a bookshop a different line from a book; a clinic a different winter tip. Write 24 one-line prompts first. A spreadsheet with day, door line and image prompt is all the plan you need.

Option A: one 48-second teaser

Generate 24 stills with bytedance-seed/seedream-4.5 ($0.05 each, $1.20). Timeline accepts up to 200 video slots and chunks the render itself past 12 segments, so 24 slots of 2 seconds is fine; the output is 48 seconds, billed as one ceil minute ($0.10). Add a music bed ($0.125). Total: 1.20 + 0.10 + 0.125 = $1.425.

Option B: 24 daily clips

Render each day as its own Timeline job with the same music bed as soundtrack, submitted a week ahead. Every job needs an Idempotency-Key. If each door is a Format run instead, a bulk queue takes up to 100 items with a concurrency window, so 24 items is one request; give each run a generation_spend_cap_usd so one bad door cannot run away. The sample below burns one door line onto a finished clip with the standalone caption job; authored cues need no speech.

import os, sys, uuid, requests

def main():
    key = os.environ.get("SUME_API_KEY", "")
    if not key:
        sys.exit("Set SUME_API_KEY first")
    body = {
        "video_url": "https://media.sume.com/artifacts/YOUR_ARTIFACT/clean.mp4",
        "style": "slam",
        "cues": [
            {"text": "Door 7: peppermint bark", "start": 0.0, "end": 3.5},
        ],
    }
    resp = requests.post(
        "https://api.sume.com/v1/video-captions",
        json=body,
        timeout=60,
        headers={"Authorization": "Bearer " + key,
                 "Idempotency-Key": str(uuid.uuid4())},
    )
    print(resp.status_code, resp.json())

if __name__ == "__main__":
    main()

What Sume does and does not do

• Does: generate the 24 stills, the music and the MP4s, with the numbers burned in if you want them.
• Does not: publish one per day or lock a door until its date. Scheduling lives in your social tool.
• Does not: judge whether a door's content suits your audience's beliefs. Some calendars are religious, with Bible verses and prayers, and some are chocolate.