44 lines
No EOL
820 B
Python
44 lines
No EOL
820 B
Python
import numpy as np
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import matplotlib.pyplot as plt
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import scipy.fftpack
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import random
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# Fe = sample rate
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# N = samples count
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def plot(Fe, N, x, y):
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plt.subplot(2, 1, 1)
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plt.plot(x, y)
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yf = scipy.fftpack.fft(y)
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xf = np.linspace(0.0, Fe/2, N/2)
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plt.subplot(2, 1, 2)
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plt.plot(xf, 2.0/N * np.abs(yf[:N/2]))
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plt.show()
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def noise(y, amp):
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return y + amp*np.random.sample(len(y))
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def simple():
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Fe = 1000
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N = Fe
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x = np.linspace(0.0, 1.0, N)
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y = np.sin(50.0 * 2.0*np.pi*x) + 0.5*np.sin(80.0 * 2.0*np.pi*x)
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y = noise(y, 2)
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plot(Fe, N, x, y)
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def real_sound_weave(freqHz):
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Fe = 16000
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durationMs = 100
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N = Fe * durationMs / 1000
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x = np.linspace(0.0, N, N)
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y = np.sin(2.0 * np.pi * x / (Fe / float(freqHz))) * 0x7FFF
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y = noise(y, 0x7fff)
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plot(Fe, N, x, y)
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real_sound_weave(4500) |