speech-scoring/speech_model.py

135 lines
4.8 KiB
Python

from __future__ import absolute_import
from __future__ import print_function
import numpy as np
from speech_data import read_siamese_tfrecords_generator
from keras.models import Model,load_model,model_from_yaml
from keras.layers import Input,Concatenate,Lambda, BatchNormalization, Dropout
from keras.layers import Dense, LSTM, Bidirectional, GRU
from keras.losses import categorical_crossentropy
from keras.utils import to_categorical
from keras.optimizers import RMSprop
from keras.callbacks import TensorBoard, ModelCheckpoint
from keras import backend as K
from keras.utils import plot_model
from speech_tools import create_dir,step_count
def create_base_rnn_network(input_dim):
'''Base network to be shared (eq. to feature extraction).
'''
inp = Input(shape=input_dim)
# ls0 = LSTM(512, return_sequences=True)(inp)
ls1 = LSTM(128, return_sequences=True)(inp)
bn_ls1 = BatchNormalization(momentum=0.98)(ls1)
ls2 = LSTM(64, return_sequences=True)(bn_ls1)
bn_ls2 = BatchNormalization(momentum=0.98)(ls2)
# ls3 = LSTM(32, return_sequences=True)(ls2)
ls4 = LSTM(32)(bn_ls2)
# d1 = Dense(128, activation='relu')(ls4)
#d2 = Dense(64, activation='relu')(ls2)
return Model(inp, ls4)
def compute_accuracy(y_true, y_pred):
'''Compute classification accuracy with a fixed threshold on distances.
'''
pred = y_pred.ravel() > 0.5
return np.mean(pred == y_true)
def accuracy(y_true, y_pred):
'''Compute classification accuracy with a fixed threshold on distances.
'''
return K.mean(K.equal(y_true, K.cast(y_pred > 0.5, y_true.dtype)))
def dense_classifier(processed):
conc_proc = Concatenate()(processed)
d1 = Dense(64, activation='relu')(conc_proc)
# dr1 = Dropout(0.1)(d1)
bn_d1 = BatchNormalization(momentum=0.98)(d1)
# d2 = Dense(128, activation='relu')(d1)
d3 = Dense(8, activation='relu')(bn_d1)
bn_d3 = BatchNormalization(momentum=0.98)(d3)
# dr2 = Dropout(0.1)(d2)
return Dense(2, activation='softmax')(bn_d3)
def siamese_model(input_dim):
base_network = create_base_rnn_network(input_dim)
input_a = Input(shape=input_dim)
input_b = Input(shape=input_dim)
processed_a = base_network(input_a)
processed_b = base_network(input_b)
final_output = dense_classifier([processed_a,processed_b])
model = Model([input_a, input_b], final_output)
return model,base_network
def write_model_arch(mod,mod_file):
model_f = open(mod_file,'w')
model_f.write(mod.to_yaml())
model_f.close()
def load_model_arch(mod_file):
model_f = open(mod_file,'r')
mod = model_from_yaml(model_f.read())
model_f.close()
return mod
def train_siamese(audio_group = 'audio',resume_weights='',initial_epoch=0):
batch_size = 128
model_dir = './models/'+audio_group
create_dir(model_dir)
log_dir = './logs/'+audio_group
create_dir(log_dir)
tr_gen_fn,te_pairs,te_y,copy_read_consts = read_siamese_tfrecords_generator(audio_group,batch_size=batch_size,test_size=batch_size)
n_step,n_features,n_records = copy_read_consts(model_dir)
tr_gen = tr_gen_fn()
input_dim = (n_step, n_features)
model,base_model = siamese_model(input_dim)
plot_model(model,show_shapes=True, to_file=model_dir+'/model.png')
plot_model(base_model,show_shapes=True, to_file=model_dir+'/base_model.png')
tb_cb = TensorBoard(
log_dir=log_dir,
histogram_freq=1,
batch_size=32,
write_graph=True,
write_grads=True,
write_images=True,
embeddings_freq=0,
embeddings_layer_names=None,
embeddings_metadata=None)
cp_file_fmt = model_dir+'/siamese_speech_model-{epoch:02d}-epoch-{val_loss:0.2f}\
-acc.h5'
cp_cb = ModelCheckpoint(
cp_file_fmt,
monitor='val_loss',
verbose=0,
save_best_only=True,
save_weights_only=True,
mode='auto',
period=1)
# train
rms = RMSprop()
model.compile(loss=categorical_crossentropy, optimizer=rms, metrics=[accuracy])
write_model_arch(model,model_dir+'/siamese_speech_model_arch.yaml')
epoch_n_steps = step_count(n_records,batch_size)
if resume_weights != '':
model.load_weights(resume_weights)
model.fit_generator(tr_gen
, epochs=10000
, steps_per_epoch=epoch_n_steps
, validation_data=([te_pairs[:, 0], te_pairs[:, 1]], te_y)
, max_queue_size=8
, callbacks=[tb_cb, cp_cb],initial_epoch=initial_epoch)
model.save(model_dir+'/siamese_speech_model-final.h5')
# y_pred = model.predict([te_pairs[:, 0], te_pairs[:, 1]])
# te_acc = compute_accuracy(te_y, y_pred)
# print('* Accuracy on test set: %0.2f%%' % (100 * te_acc))
if __name__ == '__main__':
train_siamese('test_5_words')