pyACA.FeatureSpectralRolloff Namespace Reference

Functions
	FeatureSpectralRolloff (X, f_s, kappa=0.85)
	computes the spectral rolloff from the magnitude spectrum

Function Documentation

FeatureSpectralRolloff()

FeatureSpectralRolloff	(		X,
			f_s,
			kappa = 0.85 )

computes the spectral rolloff from the magnitude spectrum

Parameters

X	spectrogram (dimension FFTLength X Observations)
f_s	sample rate of audio data
kappa	cutoff ratio (default: 0.85)

Returns

vsr: spectral rolloff (in Hz)

Definition at line 13 of file FeatureSpectralRolloff.py.

def FeatureSpectralRolloff(X, f_s, kappa=0.85):
 
    norm = X.sum(axis=0, keepdims=True)
    norm[norm == 0] = 1
 
    X = np.cumsum(X, axis=0) / norm
 
    vsr = np.argmax(X >= kappa, axis=0)
 
    # convert from index to Hz
    vsr = vsr / (X.shape[0] - 1) * f_s / 2
 
    return vsr