在每次在model.fit()函数上使用回调之前和之后,我都使用过带有一些相当简单的NN的张量板。我试图了解有关GAN的更多信息,并试图理解像这样的一些代码
class ACGAN():
def __init__(self):
# Input shape
self.img_rows = 28
self.img_cols = 28
self.channels = 1
self.img_shape = (self.img_rows, self.img_cols, self.channels)
self.num_classes = 10
self.latent_dim = 100
optimizer = Adam(0.0002, 0.5)
losses = ['binary_crossentropy', 'sparse_categorical_crossentropy']
# Build and compile the discriminator
self.discriminator = self.build_discriminator()
self.discriminator.compile(loss=losses,
optimizer=optimizer,
metrics=['accuracy'])
# Build the generator
self.generator = self.build_generator()
# The generator takes noise and the target label as input
# and generates the corresponding digit of that label
noise = Input(shape=(self.latent_dim,))
label = Input(shape=(1,))
img = self.generator([noise, label])
# For the combined model we will only train the generator
self.discriminator.trainable = False
# The discriminator takes generated image as input and determines validity
# and the label of that image
valid, target_label = self.discriminator(img)
# The combined model (stacked generator and discriminator)
# Trains the generator to fool the discriminator
self.combined = Model([noise, label], [valid, target_label])
self.combined.compile(loss=losses,
optimizer=optimizer)
def build_generator(self):
.......
def build_discriminator(self):
.........
def train(self, epochs, batch_size=128, sample_interval=50):
# Load the dataset
(X_train, y_train), (_, _) = mnist.load_data()
# Configure inputs
X_train = (X_train.astype(np.float32) - 127.5) / 127.5
X_train = np.expand_dims(X_train, axis=3)
y_train = y_train.reshape(-1, 1)
# Adversarial ground truths
valid = np.ones((batch_size, 1))
fake = np.zeros((batch_size, 1))
for epoch in range(epochs):
# ---------------------
# Train Discriminator
# ---------------------
# Select a random batch of images
idx = np.random.randint(0, X_train.shape[0], batch_size)
imgs = X_train[idx]
# Sample noise as generator input
noise = np.random.normal(0, 1, (batch_size, 100))
# The labels of the digits that the generator tries to create an
# image representation of
sampled_labels = np.random.randint(0, 10, (batch_size, 1))
# Generate a half batch of new images
gen_imgs = self.generator.predict([noise, sampled_labels])
# Image labels. 0-9 if image is valid or 10 if it is generated (fake)
img_labels = y_train[idx]
fake_labels = 10 * np.ones(img_labels.shape)
# Train the discriminator
d_loss_real = self.discriminator.train_on_batch(imgs, [valid, img_labels])
d_loss_fake = self.discriminator.train_on_batch(gen_imgs, [fake, fake_labels])
d_loss = 0.5 * np.add(d_loss_real, d_loss_fake)
# ---------------------
# Train Generator
# ---------------------
# Train the generator
g_loss = self.combined.train_on_batch([noise, sampled_labels], [valid, sampled_labels])
# Plot the progress
print ("%d [D loss: %f, acc.: %.2f%%, op_acc: %.2f%%] [G loss: %f]" % (epoch, d_loss[0], 100*d_loss[3], 100*d_loss[4], g_loss[0]))
# If at save interval => save generated image samples
if epoch % sample_interval == 0:
self.save_model()
self.sample_images(epoch)
def sample_images(self, epoch):
r, c = 10, 10
noise = np.random.normal(0, 1, (r * c, 100))
sampled_labels = np.array([num for _ in range(r) for num in range(c)])
gen_imgs = self.generator.predict([noise, sampled_labels])
# Rescale images 0 - 1
gen_imgs = 0.5 * gen_imgs + 0.5
fig, axs = plt.subplots(r, c)
cnt = 0
for i in range(r):
for j in range(c):
axs[i,j].imshow(gen_imgs[cnt,:,:,0], cmap='gray')
axs[i,j].axis('off')
cnt += 1
fig.savefig("images/%d.png" % epoch)
plt.close()
if __name__ == '__main__':
acgan = ACGAN()
acgan.train(epochs=14000, batch_size=32, sample_interval=200)
由于此代码中没有fit()函数,所以我不确定应该在哪里导入tensorboard回调以及如何可视化模型? 我删除了构建生成器和构建鉴别函数,因为我认为它不会包含在其中,但是如果我错了,请更正我。 我无法发布整个代码,所以here you go如果您需要更多详细信息
答案 0 :(得分:0)
我正在使用TF2,以下代码对我有用:
log_dir = os.path.join("logs", datetime.datetime.now().strftime("%Y%m%d-%H%M%S"))
summary_writer = tf.summary.create_file_writer(logdir=log_dir)
for epoch in range(num_epochs):
epoch_loss_avg = tf.keras.metrics.Mean()
epoch_accuracy = tf.keras.metrics.SparseCategoricalAccuracy()
for x, y in train_dataset:
loss_value, grads = grad(model, x, y)
optimizer.apply_gradients(zip(grads, model.trainable_variables))
epoch_loss_avg(loss_value)
epoch_accuracy(y, model(x))
train_loss_results.append(epoch_loss_avg.result())
train_accuracy_results.append(epoch_accuracy.result())
with summary_writer.as_default():
tf.summary.scalar('epoch_loss_avg', epoch_loss_avg.result(), step=optimizer.iterations)
tf.summary.scalar('epoch_accuracy', epoch_accuracy.result(), step=optimizer.iterations)
您可以找到完整的代码here,因为我删除了代码中的一些注释以保持答案的准确性。由于找不到TF2的文档,因此我不了解它的工作原理,我的代码只是根据我在其他人的代码中可以找到的内容进行的反复试验。