Pitch

class audioflux.Pitch(pitch_type=None, samplate=32000, low_fre=27.5, high_fre=2093.004522404789, radix2_exp=12, slide_length=1024, auto_length=2048)

Pitch - YIN, STFT, etc algorithm

Parameters

pitch_type: PitchType: Pitch type
samplate: int: Sampling rate of the incoming audio.
low_fre: float: Lowest frequency.
high_fre: float: Highest frequency.
radix2_exp: int: fft_length=2**radix2_exp
slide_length: int: Window sliding length.
auto_length: int: Auto length

Examples

Get a 220Hz’s audio file

>>> import audioflux as af
>>> audio_arr, sr = af.read(af.utils.sample_path('220'))
# >>> audio_arr = audio_arr[:8192]

Create Pitch object and get frequency

>>> from audioflux.type import PitchType
>>> obj = af.Pitch(pitch_type=PitchType.YIN)
>>> fre_arr, value_arr1, value_arr2 = obj.pitch(audio_arr)

Display plot

>>> import matplotlib.pyplot as plt
>>> from audioflux.display import fill_wave, fill_plot
>>> import numpy as np
>>> audio_len = audio_arr.shape[-1]
>>> fig, axes = plt.subplots(nrows=2)
>>> fill_wave(audio_arr, samplate=sr, axes=axes[0])
>>>
>>> ax = fill_plot(np.arange(len(fre_arr)), fre_arr, label='fre', axes=axes[1])
>>> ax.set_ylabel('frequency(Hz)')

Methods

`cal_time_length`(data_length)	Calculate the length of a frame from audio data.
`pitch`(data_arr)	Compute pitch
`set_thresh`(thresh)	Set thresh

set_thresh(thresh)

Set thresh

Parameters

thresh: float

cal_time_length(data_length)

Calculate the length of a frame from audio data.

fft_length = 2 ** radix2_exp
(data_length - fft_length) / slide_length + 1

Parameters

data_length: int: The length of the data to be calculated.

Returns

out: int

pitch(data_arr)

Compute pitch

Parameters

data_arr: np.ndarray [shape=(…, n)]: Input audio array

Returns

fre_arr: np.ndarray [shape=(…, time)]
value1_arr: np.ndarray [shape=(…, time)]
value2_arr: np.ndarray [shape=(…, time)]