def network_initializer(self, max_timesteps=None):
### build encoder
enc_input = Input(shape=(self.max_length, ),
dtype='int32',
name='input')
enc_embedding = Embedding(self.vocab_size,
self.embedding_size,
name='embedding')(enc_input)
# stacking encoding LSTMs
convos = []
for i, hs in enumerate(self.kernel_sizes):
if hs > 0:
convo_layer = Conv1D(filters=hs,
kernel_size=i + 1,
padding='same')(enc_embedding)
if self.L_pooling > 1:
convo_layer = MaxPooling1D(
pool_size=self.L_pooling)(convo_layer)
convo_layer = Flatten()(convo_layer)
convos.append(convo_layer)
enc_output = Concatenate()(convos) if len(convos) > 1 else convos[0]
enc_output = Lambda(lambda x: K.l2_normalize(x, axis=1),
name=BioactivityLSTM.ENCODING_NAME)(enc_output)
### output layer
out_layer = Dense(1, kernel_regularizer=L1L2(l2=self.l2))(enc_output)
self.model = Model(inputs=enc_input, outputs=out_layer)
self.model.compile(optimizer=self.optimizer, loss='mse')
def network_initializer(self, max_timesteps=None):
### build encoder
enc_input = Input(shape=(None, ), dtype='int32', name='input')
enc_embedding = Embedding(self.vocab_size,
self.embedding_size,
mask_zero=True,
name='embedding')(enc_input)
# stacking encoding LSTMs
hidden_states = []
enc_layer = enc_embedding
for i, layer_size in enumerate(self.layer_sizes):
return_sequences = (i != len(self.layer_sizes) - 1)
enc_layer, hidden_state, cell_state = LSTM(
layer_size,
return_sequences=return_sequences,
return_state=True,
name='lstm_%d' % (i + 1))(enc_layer)
hidden_states += [hidden_state, cell_state]
# concatenating LSTMs' states and normalizing their norms
enc_output = Concatenate()(hidden_states)
enc_output = Lambda(lambda x: K.l2_normalize(x, axis=1),
name=BioactivityLSTM.ENCODING_NAME)(enc_output)
### output layer
out_layer = Dense(1, kernel_regularizer=L1L2(l2=self.l2))(enc_output)
self.model = Model(inputs=enc_input, outputs=out_layer)
self.model.compile(optimizer=self.optimizer, loss='mse')
def build_fr_model(input_shape):
resent_model = InceptionResNetV2(include_top=False,
weights='imagenet',
input_shape=input_shape,
pooling='avg')
image_input = resent_model.input
# get the output from last layer
x = resent_model.layers[-1].output
# add a dense layer
out = Dense(128)(x)
# build the embedding model
embedder_model = Model(inputs=[image_input], outputs=[out])
# input layer
input_layer = Input(shape=input_shape)
# embed the input
x = embedder_model(input_layer)
output = Lambda(lambda x: K.l2_normalize(x, axis=-1))(x)
model = Model(inputs=[input_layer], outputs=[output])
return model
def build_fr_model(input_shape):
resent_model = InceptionResNetV2(include_top=False, weights='imagenet', input_shape=input_shape, pooling='avg')
image_input = resent_model.input
x = resent_model.layers[-1].output
out = Dense(128)(x)
embedder_model = Model(inputs=[image_input], outputs=[out])
input_layer = Input(shape=input_shape)
x = embedder_model(input_layer)
output = Lambda(lambda x: K.l2_normalize(x, axis=-1))(x)
model = Model(inputs=[input_layer], outputs=[output])
return model
def triplet_loss(y_true, y_pred):
y_pred = K.l2_normalize(y_pred, axis=1)
batch = BAT_SIZE
# print(batch)
ref1 = y_pred[0:batch, :]
pos1 = y_pred[batch:batch + batch, :]
neg1 = y_pred[batch + batch:3 * batch, :]
dis_pos = K.sum(K.square(ref1 - pos1), axis=1, keepdims=True)
dis_neg = K.sum(K.square(ref1 - neg1), axis=1, keepdims=True)
dis_pos = K.sqrt(dis_pos)
dis_neg = K.sqrt(dis_neg)
a1 = 0.6
d1 = dis_pos + K.maximum(0.0, dis_pos - dis_neg + a1)
return K.mean(d1)
def cos_distance(y_true, y_pred):
y_true = K.l2_normalize(y_true, axis=-1)
y_pred = K.l2_normalize(y_pred, axis=-1)
return K.mean(1 - K.sum((y_true * y_pred), axis=-1))
def my_cosine_distance(tensors):
if (len(tensors) != 2):
raise 'oops'
a = K.l2_normalize(tensors[0], axis=-1)
b = K.l2_normalize(tensors[1], axis=-1)
return 1 - K.mean(a * b)
def l2_normalize_layer():
return Lambda(lambda x: K.l2_normalize(x, axis=-1))
def my_cosine_proximity(tensors):
a = K.l2_normalize(tensors[0], axis=-1)
b = K.l2_normalize(tensors[1], axis=-1)
return 1 - K.mean(a * b)