Trunk-or-treat event video: plan the cost first, pull a poster frame

To promote a trunk-or-treat with photos you already have, run the unbilled Timeline 1.0 plan route on a six-slot, 30-second draft, render it for $0.10 (a 30-second output rounds up to one minute), and then pull a poster still from the finished video with video frames. The plan returns duration, segment count and estimated cost without creating a job. Halloween 2026 is Saturday, October 31, so there are still three weeks to run it.

Why plan before you render?

Volunteer-run events change details late: the lot, the start time, the number of trunks. The plan route runs the schema checks, the Sume-host URL checks and the pure compiler, and returns object timeline_plan with duration_seconds, segment_count, billable_minutes and estimated_cost_usd_micros. It does not create a job, reserve credits or download media, and it needs no Idempotency-Key. Run it every time a slot changes, then render once.

What goes into the six slots?

Use stills, since an event page needs few clips: last year's lot, a decorated trunk, the candy table, a costume parade, the sign-up poster and the map. Each slot declares its own start and duration, and stills are static holds. Choose a friendly bed prompt for the Music Router, such as playful and light with no sudden sounds. The audio spine can be silence plus the soundtrack, which keeps the whole job to pictures and one track.

How do you pull the poster frame?

Video frames takes one media.sume.com clip and either at[] times or an fps, and returns durable image artifacts at the source size. It always returns 202, so poll the job and read frames[{t,url,width,height}] when resource_status is ready. A frame that cannot be extracted comes back with a null url instead of failing the whole job. Use the t=0 frame, or pick the second where the sign-up poster is on screen, for the event page thumbnail.

What stays outside the video?

The timeline does not draw text. Put the date, time and address on the poster stills before you import them, or burn them with video captions cues for $0.20. Children appear in event photos, so get the permission your organisation requires before posting. That is a policy for you to set, not something Sume checks.