def vae_loss(x, x_decoded_mean):
xent_loss = original_dim * objectives.binary_crossentropy(x, x_decoded_mean)
kl_loss = - 0.5 * K.sum(1 + z_log_var - K.square(z_mean) - K.exp(z_log_var), axis=-1)
return xent_loss + kl_loss
python类binary_crossentropy()的实例源码
def vae_loss(x, x_decoded_mean):
xent_loss = objectives.binary_crossentropy(x, x_decoded_mean)
kl_loss = - 0.5 * K.mean(1 + z_log_sigma - K.square(z_mean) - K.exp(z_log_sigma), axis=-1)
return xent_loss + kl_loss
def vae_loss(x, x_decoded_mean):
xent_loss = objectives.binary_crossentropy(x, x_decoded_mean)
kl_loss = - 0.5 * K.mean(1 + z_log_sigma - K.square(z_mean) - K.exp(z_log_sigma), axis=-1)
return xent_loss + kl_loss
def _build(self,input_shape):
_encoder = self.build_encoder(input_shape)
_decoder = self.build_decoder(input_shape)
self.gs = self.build_gs()
self.gs2 = self.build_gs()
x = Input(shape=input_shape)
z = Sequential([flatten, *_encoder, self.gs])(x)
y = Sequential(_decoder)(flatten(z))
z2 = Input(shape=(self.parameters['N'], self.parameters['M']))
y2 = Sequential(_decoder)(flatten(z2))
w2 = Sequential([*_encoder, self.gs2])(flatten(y2))
data_dim = np.prod(input_shape)
def rec(x, y):
#return K.mean(K.binary_crossentropy(x,y))
return bce(K.reshape(x,(K.shape(x)[0],data_dim,)),
K.reshape(y,(K.shape(x)[0],data_dim,)))
def loss(x, y):
return rec(x,y) + self.gs.loss()
self.callbacks.append(LambdaCallback(on_epoch_end=self.gs.cool))
self.callbacks.append(LambdaCallback(on_epoch_end=self.gs2.cool))
self.custom_log_functions['tau'] = lambda: K.get_value(self.gs.tau)
self.loss = loss
self.metrics.append(rec)
self.encoder = Model(x, z)
self.decoder = Model(z2, y2)
self.autoencoder = Model(x, y)
self.autodecoder = Model(z2, w2)
self.net = self.autoencoder
y2_downsample = Sequential([
Reshape((*input_shape,1)),
MaxPooling2D((2,2))
])(y2)
shape = K.int_shape(y2_downsample)[1:3]
self.decoder_downsample = Model(z2, Reshape(shape)(y2_downsample))
self.features = Model(x, Sequential([flatten, *_encoder[:-2]])(x))
if 'lr_epoch' in self.parameters:
ratio = self.parameters['lr_epoch']
else:
ratio = 0.5
self.callbacks.append(
LearningRateScheduler(lambda epoch: self.parameters['lr'] if epoch < self.parameters['full_epoch'] * ratio else self.parameters['lr']*0.1))
self.custom_log_functions['lr'] = lambda: K.get_value(self.net.optimizer.lr)
def _build(self,input_shape):
dim = np.prod(input_shape) // 2
print("{} latent bits".format(dim))
M, N = self.parameters['M'], self.parameters['N']
x = Input(shape=input_shape)
_pre = tf.slice(x, [0,0], [-1,dim])
_suc = tf.slice(x, [0,dim], [-1,dim])
pre = wrap(x,_pre,name="pre")
suc = wrap(x,_suc,name="suc")
print("encoder")
_encoder = self.build_encoder([dim])
action_logit = ConditionalSequential(_encoder, pre, axis=1)(suc)
gs = self.build_gs()
action = gs(action_logit)
print("decoder")
_decoder = self.build_decoder([dim])
suc_reconstruction = ConditionalSequential(_decoder, pre, axis=1)(flatten(action))
y = Concatenate(axis=1)([pre,suc_reconstruction])
action2 = Input(shape=(N,M))
pre2 = Input(shape=(dim,))
suc_reconstruction2 = ConditionalSequential(_decoder, pre2, axis=1)(flatten(action2))
y2 = Concatenate(axis=1)([pre2,suc_reconstruction2])
def rec(x, y):
return bce(K.reshape(x,(K.shape(x)[0],dim*2,)),
K.reshape(y,(K.shape(x)[0],dim*2,)))
def loss(x, y):
kl_loss = gs.loss()
reconstruction_loss = rec(x, y)
return reconstruction_loss + kl_loss
self.metrics.append(rec)
self.callbacks.append(LambdaCallback(on_epoch_end=gs.cool))
self.custom_log_functions['tau'] = lambda: K.get_value(gs.tau)
self.loss = loss
self.encoder = Model(x, [pre,action])
self.decoder = Model([pre2,action2], y2)
self.net = Model(x, y)
self.autoencoder = self.net