Crate ferraus_analysis 

ferraus-analysis

Reusable audio analysis. Every public function takes an AudioBuffer and returns a serde-serialisable struct, so other crates (mastering, stretch, delay sync, transcription, scores) reuse exactly the numbers the analyze commands print.

Module	Main entry points
tempo	detect_tempo → TempoResult; tempo::onset_envelope, tempo::transient_density
[loudness]	loudness() / loudness_with → LoudnessReport; true_peak, loudness::integrated_lufs, loudness::loudness_outliers
spectrum	spectrum::spectrum, spectrum::third_octave_levels, spectrum::tone_balance, spectrum::tone_balance_vs_curve
stereo	stereo::stereo_analysis → stereo::StereoReport; stereo::correlation, stereo::low_correlation
levels	levels::detect_silence, levels::detect_clipping, levels::stats, levels::crest_factor_db
chords	detect_chords → ChordResult; chords::chromagram
[compare]	compare::compare → compare::CompareReport; compare::similarity, compare::mfcc
problems	problems::diagnose → problems::ProblemsReport and the individual detectors
mastering	mastering::dynamics, mastering::looks_mastered, mastering::mastering_analysis

Loudness values that cannot be measured are -inf in Rust and null in JSON.

Re-exports

pub use chords::detect_chords;

pub use chords::ChordOptions;

pub use chords::ChordResult;

pub use chords::ChordSegment;

pub use compare::compare;

pub use compare::similarity;

pub use compare::CompareOptions;

pub use compare::CompareReport;

pub use compare::SimilarityReport;

pub use levels::detect_clipping;

pub use levels::detect_silence;

pub use levels::stats;

pub use levels::ClippingReport;

pub use levels::SilenceReport;

pub use levels::StatsReport;

pub use loudness::loudness;

pub use loudness::loudness_with;

pub use loudness::true_peak;

pub use loudness::LoudnessReport;

pub use loudness::LoudnessTimeline;

pub use mastering::mastering_analysis;

pub use mastering::DynamicsReport;

pub use mastering::MasteredHeuristic;

pub use mastering::MasteringAnalysis;

pub use problems::diagnose;

pub use problems::Problem;

pub use problems::ProblemsReport;

pub use problems::Severity;

pub use spectrum::BandLevel;

pub use spectrum::Resolution;

pub use spectrum::SpectrumReport;

pub use spectrum::ToneBalance;

pub use stereo::stereo_analysis;

pub use stereo::StereoReport;

pub use tempo::detect_tempo;

pub use tempo::TempoOptions;

pub use tempo::TempoResult;

Modules

chords

Chord recognition (best-effort): peak-picked STFT chroma, harmonic-aware chord templates (maj, min, 7, maj7, min7, dim, sus4, sus2), a bass-note cue for root choice and slash chords, and Viterbi smoothing with a chord-change penalty.

compare

Null-test comparison (compare a b) and perceptual similarity (analyze similarity).

levels

Level-based analyses: silence regions, clipping runs, and per-channel amplitude statistics with an optional dB histogram.

loudness

EBU R128 / ITU-R BS.1770-4 loudness, implemented from the standard: K-weighting biquads derived for any sample rate, 400 ms momentary and 3 s short-term windows on a 100 ms grid, absolute (-70 LUFS) and relative (-10 LU) gating for integrated loudness, loudness range (EBU Tech 3342, 10th–95th percentile of gated short-term values), and true peak by polyphase oversampling.

mastering

Measurements the mastering crate decides from: dynamics (crest factor, PLR, transient density, loudness sections), the “already mastered” heuristic, and a one-call mastering_analysis that bundles loudness, tonal balance, dynamics, stereo, problems, and tempo.

problems

Diagnostics (analyze problems): each detector returns a Problem with a severity, a plain-language explanation, and a suggested fix that is a runnable command or fx stage string.

spectrum

Long-term average spectrum (Welch), fractional-octave band levels, per-bin spectra, spectral descriptors, and tonal balance against a reference spectrum or curve.

stereo

Stereo image metrics: L/R correlation (broadband and low band), mid/side balance, width and correlation per band, and a mono-compatibility score.

tempo

Tempo and beat tracking.

util

Shared DSP helpers: windows, STFT, Welch spectra, biquads, mel filterbanks, FFT cross-correlation, and small statistics. Public so sibling crates can reuse them.

Structs

AudioBuffer

Planar f32 audio: one Vec<f32> per channel, all the same length.

Functions

ops

Ops this crate contributes to the command registry: analyze tempo|loudness|silence| spectrum|clipping|chords|similarity|problems|stats|stereo and compare.