def main():
thinkdsp.random_seed(19)
signal = thinkdsp.BrownianNoise()
make_periodogram(signal)
return
signal = thinkdsp.UncorrelatedUniformNoise()
wave1 = signal.make_wave(duration=1.0, framerate=11025)
wave2 = signal.make_wave(duration=1.0, framerate=11025)
print wave1.cov(wave2)
print wave1.cov(wave1)
print wave2.cov(wave2)
print wave1.cov_mat(wave2)
print wave1.corr(wave2)
print wave1.corr(wave1)
print wave2.corr(wave2)
return
signal = thinkdsp.BrownianNoise()
process_noise(signal, root='red')
return
signal = thinkdsp.UncorrelatedUniformNoise()
process_noise(signal, root='white')
return
signal = thinkdsp.WhiteNoise()
white, integ_white = test_noise(signal, 'white-noise')
print white.estimate_slope()
signal = thinkdsp.BrownianNoise()
red, integ_red = test_noise(signal, 'red-noise')
print red.estimate_slope()
return
signal = thinkdsp.PinkNoise(beta=1.0)
pink, integ_pink = test_noise(signal, 'pink-noise')
print pink.estimate_slope()
thinkplot.preplot(num=3)
white.plot(low=1, exponent=2, label='white', linewidth=2)
pink.plot(low=1, exponent=2, label='pink', linewidth=2)
red.plot(low=1, exponent=2, label='red', linewidth=2)
thinkplot.show(xlabel='frequency (Hz)',
ylabel='power',
xscale='log',
yscale='log',
axis=[1, 18000, 1e-5, 1e8])
return
def plot_pink_noise():
"""Makes a plot showing power spectrums for pink noise.
"""
thinkdsp.random_seed(20)
duration = 1.0
framerate = 512
def make_spectrum(signal):
wave = signal.make_wave(duration=duration, framerate=framerate)
spectrum = wave.make_spectrum()
spectrum.hs[0] = 0
return spectrum
signal = thinkdsp.UncorrelatedUniformNoise()
white = make_spectrum(signal)
signal = thinkdsp.PinkNoise()
pink = make_spectrum(signal)
signal = thinkdsp.BrownianNoise()
red = make_spectrum(signal)
linewidth = 2
# colorbrewer2.org 4-class sequential OrRd
white.plot_power(label='white', color='#fdcc8a', linewidth=linewidth)
pink.plot_power(label='pink', color='#fc8d59', linewidth=linewidth)
red.plot_power(label='red', color='#d7301f', linewidth=linewidth)
thinkplot.save(root='noise-triple',
xlabel='Frequency (Hz)',
ylabel='Power',
xscale='log',
yscale='log',
xlim=[1, red.fs[-1]])
def plot_pink_noise():
"""Makes a plot showing power spectrums for pink noise.
"""
thinkdsp.random_seed(20)
duration = 1.0
framerate = 512
signal = thinkdsp.UncorrelatedUniformNoise()
wave = signal.make_wave(duration=duration, framerate=framerate)
white = wave.make_spectrum()
signal = thinkdsp.PinkNoise()
wave = signal.make_wave(duration=duration, framerate=framerate)
pink = wave.make_spectrum()
signal = thinkdsp.BrownianNoise()
wave = signal.make_wave(duration=duration, framerate=framerate)
red = wave.make_spectrum()
linewidth = 1
white.plot_power(low=1, label='white', color='gray', linewidth=linewidth)
pink.plot_power(low=1, label='pink', color='pink', linewidth=linewidth)
red.plot_power(low=1, label='red', color='red', linewidth=linewidth)
thinkplot.save(root='noise-triple',
xlabel='frequency (Hz)',
ylabel='power',
xscale='log',
yscale='log',
axis=[1, 300, 1e-4, 1e5])
def main():
plot_gaussian_noise()
thinkdsp.random_seed(20)
signal = thinkdsp.UncorrelatedUniformNoise()
process_noise(signal, root='white')
thinkdsp.random_seed(20)
signal = thinkdsp.PinkNoise(beta=1.0)
process_noise(signal, root='pink')
thinkdsp.random_seed(17)
signal = thinkdsp.BrownianNoise()
process_noise(signal, root='red')
plot_pink_noise()
# -*- coding: utf-8 -*-
"""
Created on Fri Oct 26 16:43:19 2018
@author: kiliu
"""
import sys
sys.path.append('../ThinkDsp')
import thinkdsp
import thinkplot
# White noise / UU
signal = thinkdsp.UncorrelatedUniformNoise()
wave = signal.make_wave(duration=0.5, framerate=11025)
wave.write(filename='uu.wav')
segment = wave.segment(start=0, duration=0.01)
segment.plot()
thinkplot.show()
spectrum = wave.make_spectrum()
spectrum.plot()
thinkplot.show()
#spectrum.plot_power()
#thinkplot.show()
spectrum.plot_power(linewidth=1, alpha=0.5)
thinkplot.config(xscale='log', yscale='log')
thinkplot.show()