Muze

Muze is a Ruby audio feature extraction library that provides a full pipeline from audio loading to spectral analysis, feature extraction, rhythm analysis, effects, and lightweight visualization.

Installation

Add this line to your application's Gemfile:

gem "muze"

Then execute:

bundle install

Or install directly:

gem install muze

Quick Start

require "muze"

y, sr = RAF.load("sample.wav", sr: 22_050)
mel = RAF.melspectrogram(y:, sr:)
mfcc = RAF.mfcc(y:, sr:, n_mfcc: 13)
tempo, beats = RAF.beat_track(y:, sr:)
RAF.specshow(Muze.power_to_db(mel), output: "mel.svg")

Main Features

Area	APIs
Audio I/O	`RAF.load` (`wav`, `flac`, `mp3`, `ogg`)
STFT stack	`RAF.stft`, `RAF.istft`, `RAF.magphase`
Scale helpers	`RAF.power_to_db`, `RAF.amplitude_to_db`
Filters	`RAF.mel`, `RAF.chroma`
Features	`RAF.melspectrogram`, `RAF.mfcc`, `RAF.delta`
Spectral descriptors	centroid, bandwidth, rolloff, flatness, contrast, zcr, rms
Rhythm	`RAF.onset_strength`, `RAF.onset_detect`, `RAF.beat_track`, `RAF.tempogram`
Effects	`RAF.hpss`, `RAF.time_stretch`, `RAF.pitch_shift`, `RAF.trim`
Visualization	`RAF.specshow`, `RAF.waveshow`

wav is loaded with wavify, and flac/mp3/ogg requires ffmpeg + ffprobe available on PATH.

Development

bundle install
bundle exec rspec

Benchmark and regression check:

bundle exec rake bench

This writes a JSON report to benchmarks/reports/latest.json and compares metrics against benchmarks/baseline.json. To refresh the baseline:

MUZE_BENCH_UPDATE_BASELINE=1 bundle exec rake bench

Quality regression thresholds for effects are documented in benchmarks/quality_thresholds.md.

Optional native extension:

bundle exec rake compile

Generate API docs:

bundle exec yard doc

License

Muze is available under the MIT License.