music.noise

music.noise(noise_type='brown', duration=2, min_freq=15, max_freq=15000, number_of_samples=0, sample_rate=44100)

Return a colored or user-refined noise.

Parameters:

noise_typestr or scalar

Specifies the decibels gain or attenuation per octave. It can be specified numerically (e.g. ntype=3.5 is 3.5 decibels gain per octave) or by strings: - “brown” is -6dB/octave - “pink” is -3dB/octave - “white” is 0dB/octave - “blue” is 3dB/octave - “violet” is 6dB/octave - “black” is -12/dB/octave but, in theory, is any < -6dB/octave See [1] for more information.

durationscalar

The duration of the noise in seconds.

min_freqscalar in [0, fs/2]

The lowest frequency allowed.

max_freqscalar in [0, fs/2]

The highest frequency allowed. It should be > fmin.

number_of_samplesinteger

The number of samples of the resulting sonic vector.

sample_rateinteger

The sample rate to use, by default 44100.

Returns:

ndarray

A mono sequence of PCM samples, normalized to [-1, 1].

Raises:

ValueError

If noise_type is neither a number of decibels per octave nor one of the named colours. A misspelt colour would otherwise render as silence or as an unrelated slope.

Parameters:

• noise_type (str | float)

• duration (float)

• min_freq (float)

• max_freq (float)

• number_of_samples (int)

• sample_rate (int)

Return type:

NDArray[float64]

Notes

The noise is synthesized with components with random phases, with the moduli that are related to the decibels/octave, and with a frequency resolution of fs / nsamples = fs / (fs*d) = 1/d Hz

Cite the following article whenever you use this function.

References

[1]

Fabbri, Renato, et al. “Musical elements in the discrete-time representation of sound.” arXiv preprint arXiv:abs/1412.6853 (2017)

Examples

>>> hiss = noise("white", duration=0.5)     # flat, 0 dB per octave
>>> len(hiss)
22050
>>> darker = noise("brown", duration=0.5)   # -6 dB per octave
>>> tilted = noise(-9, duration=0.5)        # or any slope you name