rhythm.py
python
| 1 | """muse rhythm — rhythmic analysis of a MIDI track. |
| 2 | |
| 3 | Quantifies syncopation, quantisation accuracy, swing ratio, and dominant note |
| 4 | length. In a world of agent swarms, rhythm is the temporal contract between |
| 5 | parts — this command makes it inspectable and diffable across commits. |
| 6 | |
| 7 | Usage:: |
| 8 | |
| 9 | muse rhythm tracks/drums.mid |
| 10 | muse rhythm tracks/melody.mid --commit HEAD~3 |
| 11 | muse rhythm tracks/bass.mid --json |
| 12 | |
| 13 | Output:: |
| 14 | |
| 15 | Rhythmic analysis: tracks/drums.mid — working tree |
| 16 | Notes: 64 · Bars: 8 · Notes/bar avg: 8.0 |
| 17 | Dominant subdivision: sixteenth |
| 18 | Quantisation score: 0.94 (very tight) |
| 19 | Syncopation score: 0.31 (moderate) |
| 20 | Swing ratio: 1.42 (moderate swing) |
| 21 | """ |
| 22 | |
| 23 | from __future__ import annotations |
| 24 | |
| 25 | import json |
| 26 | import logging |
| 27 | import pathlib |
| 28 | |
| 29 | import typer |
| 30 | |
| 31 | from muse.core.errors import ExitCode |
| 32 | from muse.core.repo import require_repo |
| 33 | from muse.core.store import read_current_branch, resolve_commit_ref |
| 34 | from muse.plugins.midi._analysis import RhythmAnalysis, analyze_rhythm |
| 35 | from muse.plugins.midi._query import load_track, load_track_from_workdir |
| 36 | |
| 37 | logger = logging.getLogger(__name__) |
| 38 | app = typer.Typer() |
| 39 | |
| 40 | |
| 41 | def _read_repo_id(root: pathlib.Path) -> str: |
| 42 | import json as _json |
| 43 | |
| 44 | return str(_json.loads((root / ".muse" / "repo.json").read_text())["repo_id"]) |
| 45 | |
| 46 | |
| 47 | def _read_branch(root: pathlib.Path) -> str: |
| 48 | return read_current_branch(root) |
| 49 | |
| 50 | |
| 51 | def _quant_label(score: float) -> str: |
| 52 | if score >= 0.95: |
| 53 | return "very tight" |
| 54 | if score >= 0.80: |
| 55 | return "tight" |
| 56 | if score >= 0.60: |
| 57 | return "moderate" |
| 58 | return "loose / human" |
| 59 | |
| 60 | |
| 61 | def _synco_label(score: float) -> str: |
| 62 | if score < 0.10: |
| 63 | return "straight" |
| 64 | if score < 0.30: |
| 65 | return "mild" |
| 66 | if score < 0.55: |
| 67 | return "moderate" |
| 68 | return "highly syncopated" |
| 69 | |
| 70 | |
| 71 | def _swing_label(ratio: float) -> str: |
| 72 | if ratio < 1.10: |
| 73 | return "straight" |
| 74 | if ratio < 1.30: |
| 75 | return "light swing" |
| 76 | if ratio < 1.60: |
| 77 | return "moderate swing" |
| 78 | return "heavy swing" |
| 79 | |
| 80 | |
| 81 | @app.callback(invoke_without_command=True) |
| 82 | def rhythm( |
| 83 | ctx: typer.Context, |
| 84 | track: str = typer.Argument(..., metavar="TRACK", help="Workspace-relative path to a .mid file."), |
| 85 | ref: str | None = typer.Option( |
| 86 | None, "--commit", "-c", metavar="REF", |
| 87 | help="Analyse a historical snapshot instead of the working tree.", |
| 88 | ), |
| 89 | as_json: bool = typer.Option(False, "--json", help="Emit results as JSON."), |
| 90 | ) -> None: |
| 91 | """Quantify syncopation, swing, and quantisation accuracy in a MIDI track. |
| 92 | |
| 93 | ``muse rhythm`` gives agents and composers a numerical fingerprint of a |
| 94 | track's rhythmic character — how quantised is it, how much does it swing, |
| 95 | how syncopated? These metrics are invisible in Git; Muse computes them |
| 96 | from structured note data at any point in history. |
| 97 | |
| 98 | Use ``--json`` for agent-readable output to drive automated rhythmic |
| 99 | quality gates or style-matching pipelines. |
| 100 | """ |
| 101 | root = require_repo() |
| 102 | commit_label = "working tree" |
| 103 | |
| 104 | if ref is not None: |
| 105 | repo_id = _read_repo_id(root) |
| 106 | branch = _read_branch(root) |
| 107 | commit = resolve_commit_ref(root, repo_id, branch, ref) |
| 108 | if commit is None: |
| 109 | typer.echo(f"❌ Commit '{ref}' not found.", err=True) |
| 110 | raise typer.Exit(code=ExitCode.USER_ERROR) |
| 111 | result = load_track(root, commit.commit_id, track) |
| 112 | commit_label = commit.commit_id[:8] |
| 113 | else: |
| 114 | result = load_track_from_workdir(root, track) |
| 115 | |
| 116 | if result is None: |
| 117 | typer.echo(f"❌ Track '{track}' not found or not a valid MIDI file.", err=True) |
| 118 | raise typer.Exit(code=ExitCode.USER_ERROR) |
| 119 | |
| 120 | notes, _tpb = result |
| 121 | if not notes: |
| 122 | typer.echo(f" (no notes found in '{track}')") |
| 123 | return |
| 124 | |
| 125 | analysis: RhythmAnalysis = analyze_rhythm(notes) |
| 126 | |
| 127 | if as_json: |
| 128 | typer.echo(json.dumps({"track": track, "commit": commit_label, **analysis}, indent=2)) |
| 129 | return |
| 130 | |
| 131 | typer.echo(f"\nRhythmic analysis: {track} — {commit_label}") |
| 132 | typer.echo( |
| 133 | f"Notes: {analysis['total_notes']} · " |
| 134 | f"Bars: {analysis['bars']} · " |
| 135 | f"Notes/bar avg: {analysis['notes_per_bar_avg']}" |
| 136 | ) |
| 137 | typer.echo(f"Dominant subdivision: {analysis['dominant_subdivision']}") |
| 138 | qs = analysis["quantization_score"] |
| 139 | ss = analysis["syncopation_score"] |
| 140 | sw = analysis["swing_ratio"] |
| 141 | typer.echo(f"Quantisation score: {qs:.3f} ({_quant_label(qs)})") |
| 142 | typer.echo(f"Syncopation score: {ss:.3f} ({_synco_label(ss)})") |
| 143 | typer.echo(f"Swing ratio: {sw:.3f} ({_swing_label(sw)})") |