phasenn/phasenn_test6.py

158 lines
4.9 KiB
Python
Executable File

#!/usr/bin/python3
# phasenn_test6.py
#
# David Rowe Oct 2019
# Extending test5 to deal with input/output vectors that have slightly
# different "rates", i.e. Wo changing across the frame which is usual
# for voiced speech.
import numpy as np
import sys
from keras.layers import Dense
from keras import models,layers
from keras import initializers
import matplotlib.pyplot as plt
# constants
N = 80 # number of time domain samples in frame
nb_samples = 100000
nb_batch = 32
nb_epochs = 25
width = 256
pairs = 2*width
fo_min = 50
fo_max = 400
Fs = 8000
dfo = 0.02
# Generate training data. Given the phase at the start of the frame,
# and the frequency, determine the phase at the end of the frame
# phase encoded as cos,sin pairs ref:
phase_start = np.zeros((nb_samples, pairs))
phase_end = np.zeros((nb_samples, pairs))
Wo_N = np.zeros(nb_samples)
Wo_0 = np.zeros(nb_samples)
L = np.zeros(nb_samples, dtype=int)
for i in range(nb_samples):
# parameters at time 0 (start of current frame)
# distribute fo randomnly on a log scale
r = np.random.rand(1)
log_fo_0 = np.log10(fo_min) + (np.log10(fo_max)-np.log10(fo_min))*r[0]
fo_0 = 10 ** log_fo_0
Wo_0[i] = fo_0*2*np.pi/Fs
L_0 = int(np.floor(np.pi/Wo_0[i]))
# parameters at time N (end of current frame), allow a df0 freq change
# across frame, typical of voiced speech
r = np.random.rand(1)
fo_N = fo_0 + (-2*dfo + dfo*r[0])*fo_0
fo_N = np.max((fo_min, fo_N))
fo_N = np.min((fo_max, fo_N))
#fo_N = fo_0
Wo_N[i] = fo_N*2*np.pi/Fs
L_N = int(np.floor(np.pi/Wo_N[i]))
L[i] = np.min((L_0, L_N))
#print("fo: %f %f L: %d %d min: %d" % (fo_0, fo_N, L_0, L_N, L[i]))
for m in range(1,L[i]):
bin_0 = int(np.round(m*Wo_0[i]*width/np.pi))
mWo_0 = bin_0*np.pi/width
bin_N = int(np.round(m*Wo_N[i]*width/np.pi))
mWo_N = bin_N*np.pi/width
#print("m: %d bin_0: %d bin_N: %d" % (m, bin_0,bin_N))
r = np.random.rand(1)
phase_start_pol = -np.pi + r[0]*2*np.pi
phase_start[i,2*bin_0] = np.cos(phase_start_pol)
phase_start[i,2*bin_0+1] = np.sin(phase_start_pol)
# phase shift average of two frequencies
phase_end_pol = phase_start_pol + N*(mWo_0 + mWo_N)/2
phase_end[i,2*bin_N] = np.cos(phase_end_pol)
phase_end[i,2*bin_N+1] = np.sin(phase_end_pol)
print(Wo_0.shape, Wo_N.shape, phase_start.shape)
input = np.column_stack([Wo_0, Wo_N, phase_start])
print(input.shape)
print(phase_end.shape)
model = models.Sequential()
model.add(layers.Dense(pairs, activation='relu', input_dim=(pairs+2)))
model.add(layers.Dense(pairs))
model.summary()
# Compile and fit our model
from keras import optimizers
sgd = optimizers.SGD(lr=0.04, decay=1e-6, momentum=0.9, nesterov=True)
model.compile(loss='mse', optimizer=sgd)
history = model.fit(input, phase_end, batch_size=nb_batch, epochs=nb_epochs)
# measure error in rectangular coordinates over all samples
phase_end_est = model.predict(input)
ind = np.nonzero(phase_end)
err = (phase_end[ind] - phase_end_est[ind])
var = np.var(err)
std = np.std(err)
print("rect var: %f std: %f" % (var,std))
print(phase_end_est.shape, err.shape)
c1 = phase_end[ind]; c1 = c1[::2] + 1j*c1[1::2]
c2 = phase_end_est[ind]; c2 = c2[::2] + 1j*c2[1::2]
err_angle = np.angle(c1 * np.conj(c2))
print(err_angle[:5],err_angle.shape)
var = np.var(err_angle)
std = np.std(err_angle)
print("angle var: %4.2f std: %4.2f rads" % (var,std))
print("angle var: %4.2f std: %4.2f degs" % (var*180/np.pi,std*180/np.pi))
def sample_model(r):
phase = np.zeros(width, dtype=complex)
phase_est = np.zeros(width, dtype=complex)
phase_err = np.zeros(width, dtype=complex)
for m in range(1,L[r]):
wm = m*Wo_N[r]
bin = int(np.round(wm*width/np.pi))
phase[m] = phase_end[r,2*bin] + 1j*phase_end[r,2*bin+1]
phase_est[m] = phase_end_est[r,2*bin] + 1j*phase_end_est[r,2*bin+1]
phase_err[m] = phase[m] * np.conj(phase_est[m])
return phase, phase_err
plot_en = 1;
if plot_en:
plt.figure(1)
plt.plot(history.history['loss'])
plt.title('model loss')
plt.xlabel('epoch')
plt.show(block=False)
plt.figure(2)
plt.subplot(211)
plt.hist(err_angle*180/np.pi, bins=20)
plt.subplot(212)
plt.hist(Wo_0*(Fs/2)/np.pi, bins=20)
plt.title('phase angle error (deg) and fo (Hz)')
plt.show(block=False)
plt.figure(3)
plt.title('sample vectors and error')
for r in range(12):
plt.subplot(3,4,r+1)
phase, phase_err = sample_model(r)
plt.plot(np.angle(phase[1:L[r]+1])*180/np.pi,'g')
plt.plot(np.angle(phase_err[1:L[r]+1])*180/np.pi,'r')
plt.show(block=False)
# click on last figure to close all and finish
plt.waitforbuttonpress(0)
plt.close()