30, 15 and 6-second cutdowns from one master with video trim

Run video trim three times on the same master with duration set to 30, 15 and 6, and you have three cutdowns for $0.06 in total: the public rate is $0.02 per job. Each call returns a new MP4 artifact, the master stays untouched, and the default precision: exact makes frame-accurate cuts. If the three cutdowns all need a 1080x1920 frame, add output: { width: 1080, height: 1920 } to each request.

A trim is a plain range cut. It does not choose the best seconds for you, so decide the in-points first, by watching the master or by pulling stills with video frames.

The three requests

The fields are video_url, start and exactly one of end or duration. Sending both is refused with video_trim_range_conflict, and sending neither with video_trim_range_required. Duration runs from 0.2 to 900 seconds, and the source can be up to 1800 seconds long.

For a 6-second bumper-style cut you will often want to drop the sound and lay a new bed in Timeline later: set audio: "drop". For cutdowns that keep the original voice, leave it at the default keep; exact precision remuxes the kept audio as AAC.

A script that sends all three

The script below sends three trims, each with its own idempotency key, and prints the job ids. The jobs run async, so poll /v1/jobs/:id/status until result_ready, then read /v1/jobs/:id/result for the new video_url.

const cuts = [["c30", 12, 30], ["c15", 20, 15], ["c06", 24, 6]];
async function trim([key, start, duration]) {
  const res = await fetch("https://api.sume.com/v1/video-trim", {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.SUME_API_KEY}`,
      "Content-Type": "application/json",
      "Idempotency-Key": `master-${key}`,
    },
    body: JSON.stringify({
      video_url: "https://media.sume.com/artifacts/artf_demo/master.mp4",
      start,
      duration,
      output: { width: 1080, height: 1920 },
    }),
  });
  return res.json();
}
async function main() {
  const jobs = await Promise.all(cuts.map(trim));
  for (const job of jobs) console.log(job.request_id ?? job);
}
main();

Exact or keyframe

precision: exact re-encodes with libx264 and yuv420p, so the cut starts where you said. precision: keyframe copies the stream, which can start a group of pictures early; the result carries actual_start_seconds so you can re-base your times. The output conform works only with exact, and combining it with keyframe is refused with video_trim_output_requires_exact.

If end is beyond the source, the cut clamps to the end of the source and the result warns with trim_clamped_to_source. Check the returned duration_seconds rather than assuming you got the length you asked for.

Matching the cutdown to a placement

Google's page on YouTube video ad lengths and formats lists the lengths for each format, and the related post on YouTube ad formats turns them into Timeline minutes. A 6-second cutdown suits a bumper-length slot; 15 and 30 seconds suit the longer in-stream formats. Read the page for the current numbers rather than relying on this post, which only shows the cutting mechanics.

Cutdowns that need new music or a new voiceover go through Timeline next, where a 30-second render is one billable minute at $0.10.

Budget for a campaign

Cost scales linearly with the number of masters. Twelve masters, each cut to 30, 15 and 6 seconds, is 36 trim jobs and 36 x $0.02 = $0.72. If each cutdown then goes through one Timeline render of a minute or less to add a voiceover, that adds 36 x $0.10 = $3.60, for a combined $4.32. Those figures count only trim and Timeline; they exclude generating the master itself.

Keep the job ids with the cutdown length in your own records, because the result carries a new artifact id for each file and nothing about which cutdown it was. Use the idempotency key as the label: a key such as master-c15 makes a retry safe and tells you what the request was.

Picking the in-points

Pick in-points from stills. Video frames returns an exact still at a time you choose, and video inspect can return up to 24 stills in one call at frames.at. Look at them at a few candidate starts, choose where the action begins, and put those values into start. Doing so before the trims saves redo jobs at $0.02 each.