Beat Grid Export

Overview

Onset Engine detects a full beat grid for every track it analyses — beats, downbeats, tempo and structure. Beat grid export writes that grid out as a file so you can use it in other tools.

This is useful anywhere you need accurate musical timing outside Onset: scripting, overlay work, subtitle timing, or driving your own tooling.

Tip

Beat export is not license-gated. It works in the free demo.

Exporting

From the GUI

In the AUDIO tab of the asset bin, each track has a ⇩ BEATS button. Click it and the console switches over to show progress; when it finishes, a dialog reports the files written and offers to open the containing folder.

From the CLI

OnsetEngine.exe export-beats song.mp3

Options:

# One specific format
OnsetEngine.exe export-beats song.mp3 --format funscript

# Write somewhere specific (single format only)
OnsetEngine.exe export-beats song.mp3 --format csv --out C:\work\grid.csv

--format accepts funscript, labels, csv, or all (the default).

Output formats

All three are written next to the audio file, suffixed _beats so they can never overwrite a file you already have.

song_beats.funscript

The beat grid as a metronome pattern — position alternates on each detected beat. Loads into OpenFunscripter, script players, and heatmap tools as a timing reference.

{
  "version": "1.0",
  "metadata": { "creator": "Onset Engine", "type": "beat-grid" },
  "actions": [
    { "at": 511, "pos": 90 },
    { "at": 998, "pos": 10 }
  ]
}

at is milliseconds; pos is 0–100.

song_beats.txt

An Audacity label track — tab-separated, one point label per beat. Downbeats are labelled downbeat so bar starts stand out while scrubbing.

0.510839  0.510839  downbeat
0.998458  0.998458  beat

Import via File → Import → Labels.

song_beats.csv

Plain rows for your own tooling:

time_s,type
0.510839,downbeat
0.998458,beat

The reverse direction

Beat export writes timing out. Onset can also read an intensity curve back in and use it to drive an edit — see Energy Curves.

Notes

• Detection runs the same analysis the editor uses, so an exported grid matches what a render would cut to.
• Everything runs locally; nothing is uploaded.
• Accuracy depends on the track. Steady percussive material detects cleanly; rubato or beatless material is inherently ambiguous.