madmom.audio.comb_filters

This module contains comb-filter and comb-filterbank functionality.

class madmom.audio.comb_filters.CombFilterbankProcessor

CombFilterbankProcessor class.

Parameters:

filter_function : filter function or str

Filter function to use {feed_forward_comb_filter, feed_backward_comb_filter} or a string literal {‘forward’, ‘backward’}.

tau : list or numpy array, shape (N,)

Delay length(s) [frames].

alpha : list or numpy array, shape (N,)

Corresponding scaling factor(s).

Notes

tau and alpha must have the same length.

process(self, data)

Process the given data with the comb filter.

Parameters:

data : numpy array

Data to be filtered/processed.

Returns:

comb_filtered_data : numpy array

Comb filtered data with the different taus aligned along the (new) first dimension.

madmom.audio.comb_filters.comb_filter(signal, filter_function, tau, alpha)

Filter the signal with a bank of either feed forward or backward comb filters.

Parameters:

signal : numpy array

Signal.

filter_function : {feed_forward_comb_filter, feed_backward_comb_filter}

Filter function to use (feed forward or backward).

tau : list or numpy array, shape (N,)

Delay length(s) [frames].

alpha : list or numpy array, shape (N,)

Corresponding scaling factor(s).

Returns:

comb_filtered_signal : numpy array

Comb filtered signal with the different taus aligned along the (new) first dimension.

Notes

tau and alpha must be of same length.

madmom.audio.comb_filters.feed_backward_comb_filter(signal, tau, alpha)

Filter the signal with a feed backward comb filter.

Parameters:

signal : numpy array

Signal.

tau : int

Delay length.

alpha : float

Scaling factor.

Returns:

comb_filtered_signal : numpy array

Comb filtered signal.

Notes

y[n] = x[n] + α * y[n - τ] is used as a filter function.

madmom.audio.comb_filters.feed_backward_comb_filter_1d(ndarray signal, unsigned int tau, float alpha)

Filter the signal with a feed backward comb filter.

Parameters:

signal : 1D numpy array, float dtype

Signal.

tau : int

Delay length.

alpha : float

Scaling factor.

Returns:

comb_filtered_signal : numpy array

Comb filtered signal.

Notes

y[n] = x[n] + α * y[n - τ] is used as a filter function.

madmom.audio.comb_filters.feed_backward_comb_filter_2d(ndarray signal, unsigned int tau, float alpha)

Filter the signal with a feed backward comb filter.

Parameters:

signal : 2D numpy array, float dtype

Signal.

tau : int

Delay length.

alpha : float

Scaling factor.

Returns:

comb_filtered_signal : numpy array

Comb filtered signal.

Notes

y[n] = x[n] + α * y[n - τ] is used as a filter function.

madmom.audio.comb_filters.feed_forward_comb_filter(signal, tau, alpha)

Filter the signal with a feed forward comb filter.

Parameters:

signal : numpy array

Signal.

tau : int

Delay length.

alpha : float

Scaling factor.

Returns:

comb_filtered_signal : numpy array

Comb filtered signal.

Notes

y[n] = x[n] + α * x[n - τ] is used as a filter function.