pyA is a package to support creation and manipulation of audio signals with Python. It uses numpy arrays to store and compute audio signals.

• Website: --
• Documentation: see examples/pya-examples.ipynb and help(pya)
• Source code: https://github.com/thomas-hermann/pya

It provides:

• Asig - a versatile audio signal class
  • Ugen - a subclass of Asig, which offers unit generators such as sine, square, swatooth, noise
• Aserver - an audio server class for queuing and playing Asigs
• Aspec - an audio spectrum class, using rfft as real-valued signals are always implied
• Astft - an audio STFT (short-term Fourier transform) class

pyA can be used for

• multi-channel audio processing
• auditory display and sonification
• sound synthesis experiment
• audio applications in general such as games or GUI-enhancements
• signal analysis and plotting
• at this time more suitable for offline rendering than realtime.

Disclaimer: We are currently making sure that pyA can be uploaded to PyPI, until then clone the master branch and from inside the pya directory install via pip install -e .

Use pip to install pya via

pip install pya

Besides numpy, scipy and matplotlib, pyA requires pyaudio which in turn requires portaudio. Note that Linux/Windows users should make sure that the corresponding binary packages are installed.

See pyaudio installation https://people.csail.mit.edu/hubert/pyaudio/#downloads

Anaconda can install non-python packages, so that the easiest way (if applicable) would be to

conda install pyaudio

from pya import *
s = Aserver(bs=1024)
Aserver.default = s  # to set as default server
s.boot()   

A 1s / 440 Hz sine tone at sampling rate 44100 as channel name 'left':

import numpy as np
signal_array = np.sin(2 * np.pi * 440 * np.linspace(0, 1, 44100))
atone = Asig(signal_array, sr=44100, label='1s sine tone', cn=['left'])

• atone.sig --> The numpy array containing the signal is
• atone.sr --> the sampling rate
• atone.cn --> the list of custom defined channel names
• atone.label --> a custom set identifier string

atone.play(server=s)  

play() uses Aserver.default if server is not specified

to plot the first 1000 samples:

atone[:1000].plot()

to plot the magnitude and phase spectrum:

atone.plot_spectrum()

to plot the spectrum via the Aspec class

atone.to_spec().plot()

to plot the spectrogram via the Astft class

atone.to_stft().plot(ampdb)

• Asigs support multi-channel audio (as columns of the signal array)
  • a1[:100, [:3]] would select the first 100 samples and the first 3 channels,
  • a1[{1.2:2}, ['left']] would select the channel named 'left' using a time slice from 1

Asig methods usually return an Asig, so methods can be chained, e.g

atone[{0:1.5}].fade_in(0.1).fade_out(0.8).gain(db=-6).plot(lw=0.1).play(rate=0.4, onset=1)

• Please check the examples/pya-examples.ipynb for more examples and details.

• Please get in touch with us if you wish to contribute. We are happy to be involved in the discussion of new features and to receive pull requests.