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phasenn
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added 2nd formant simulation

master
David 2019-11-24 10:06:07 +10:30
parent c2ac3d520c
commit a3d92a4d29
1 changed files with 14 additions and 9 deletions
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23
phasenn_test11.py
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@ -87,22 +87,27 @@ for i in range(nb_samples):
# pitch period in samples
P = 2*L[i]
r = np.random.rand(3)
# sample 2nd order IIR filter with random peak freq, choose alpha
# and gamma to get something like voiced speech
alpha = 0.1*np.pi + 0.4*np.pi*r[0]
gamma = 0.9 + 0.09*r[1]
w,h = signal.freqz(1, [1, -2*gamma*np.cos(alpha), gamma*gamma], range(1,L[i]+1)*Wo[i])
r = np.random.rand(2)
alpha1 = 0.05*np.pi + 0.25*np.pi*r[0]
gamma1 = 0.9 + 0.09*r[1]
w1,h1 = signal.freqz(1, [1, -2*gamma1*np.cos(alpha1), gamma1*gamma1], range(1,L[i]+1)*Wo[i])
r = np.random.rand(2)
alpha2 = alpha1 + 0.4*np.pi*r[0]
gamma2 = 0.8 + 0.1*r[1]
w2,h2 = signal.freqz(1, [1, -2*gamma2*np.cos(alpha2), gamma2*gamma2], range(1,L[i]+1)*Wo[i])
# select n0 between 0...P-1 (it's periodic)
n0[i] = r[2]*P
r = np.random.rand(1)
n0[i] = r[0]*P
e = np.exp(-1j*n0[i]*range(1,L[i]+1)*Wo[i])
for m in range(1,L[i]+1):
amp[i,m] = np.log10(np.abs(h[m-1]))
phase[i,m] = np.angle(h[m-1]*e[m-1])
phase_disp[i,m] = np.angle(h[m-1])
amp[i,m] = np.log10(np.abs(h1[m-1]*h2[m-1]))
phase[i,m] = np.angle(h1[m-1]*h2[m-1]*e[m-1])
phase_disp[i,m] = np.angle(h1[m-1]*h2[m-1])
# use regular DSP to estimate n0, and remove effect of linear phase