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.

Re-export grids you made before v1.0.12

Before v1.0.12, downbeats were not detected — they were assumed, by counting every fourth beat from the first one. That holds up on straightforward 4/4 rock and pop, but on electronic music it was close to worthless, and on some tracks the whole grid locked onto double the real tempo.

v1.0.12 replaced this with real joint beat and downbeat detection. The beat positions are tighter and the downbeat markers are now genuinely where the bars start. If you exported a grid from an electronic track and found the bar markers unusable, export it again — it is a different file now.

Exporting

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.

All three formats are written in one go, so there is nothing to choose.

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.