Beat-Synced Cut — effect skill for cuts & pacing

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Place cuts on the beats of the music so the edit feels driven by the track.

What it does

Built on Beat Timeline by HeyGen (HyperFrames), Apache-2.0. The write-up and recipes below are varg's.

Every cut lands on a kick, snare or downbeat; bigger changes on the bar or the drop.

When: Montages, music videos, reels, ads with a music bed.

Watch out: Cutting on every single beat for a whole piece gets monotonous; vary between beats, half-bars and bars.

Timing: Cut 1–2 frames before the transient so the change lands with the sound

Also called: cut to the beat, beat sync, music sync, auto beat

In FFmpeg

FFmpeg has no beat tracker. Get beat times elsewhere (e.g. aubio beat song.wav, librosa, or npx hyperframes beats), then trim each shot to the gap between beats:

# beats.txt: 0.00 0.52 1.04 1.56 ...
ffmpeg -i s1.mp4 -i s2.mp4 -i s3.mp4 -i song.wav -filter_complex \
"[0:v]trim=0:0.52,setpts=PTS-STARTPTS[a];[1:v]trim=0:0.52,setpts=PTS-STARTPTS[b];\
 [2:v]trim=0:1.04,setpts=PTS-STARTPTS[c];[a][b][c]concat=n=3:v=1:a=0[v]" \
  -map "[v]" -map 3:a -shortest out.mp4

In HyperFrames

npx hyperframes beats writes a Studio beat grid for the music <audio> (data-timeline-role="music"); for a full beat-cut video use the music-to-video workflow. Blocks: beat-timeline, beat-accent, beat-freeze-cut.

In Remotion

Convert beat seconds to frames (Math.round(t * fps)), compute each durationInFrames as the difference, map to <Series.Sequence>, and add <Audio> for the track.

In CapCut

Select the music → Beats (auto beat markers) → cut clips to the markers; templates also auto-sync clips to beats.

Ready-made components

Where this comes from

Use when

Not for

Install

Example output

https://s3.varg.ai/how-to/previews/9f0cdccc8f5e/take-beat-synced-cut.mp4 — montage between two shots, with the timeline strip of the edit. Footage: Big Buck Bunny (2008), (c) copyright 2008, Blender Foundation | www.bigbuckbunny.org, CC BY 3.0; Coffee Run (2020), Blender Studio | studio.blender.org, CC BY 4.0. (credit: Rendered by varg · Big Buck Bunny (2008) + Coffee Run (2020))

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