Filters

Filter bank construction

mel(sr, n_fft[, n_mels, fmin, fmax, htk, norm]) Create a Filterbank matrix to combine FFT bins into Mel-frequency bins
chroma(sr, n_fft[, n_chroma, A440, ctroct, …]) Create a Filterbank matrix to convert STFT to chroma
constant_q(sr[, fmin, n_bins, …]) Construct a constant-Q basis.
_multirate_fb([center_freqs, sample_rates, …]) Helper function to construct a multirate filterbank.
semitone_filterbank([center_freqs, tuning, …]) Constructs a multirate filterbank of infinite-impulse response (IIR) band-pass filters at user-defined center frequencies and sample rates.

Window functions

window_bandwidth(window[, n]) Get the equivalent noise bandwidth of a window function.
get_window(window, Nx[, fftbins]) Compute a window function.

Miscellaneous

constant_q_lengths(sr, fmin[, n_bins, …]) Return length of each filter in a constant-Q basis.
cq_to_chroma(n_input[, bins_per_octave, …]) Convert a Constant-Q basis to Chroma.
mr_frequencies(tuning) Helper function for generating center frequency and sample rate pairs.
window_sumsquare(window, n_frames[, …]) Compute the sum-square envelope of a window function at a given hop length.

Deprecated

dct(n_filters, n_input) Discrete cosine transform (DCT type-II, normalized) basis.