def mnist(layers, # pylint: disable=invalid-name
activation="sigmoid",
batch_size=128,
mode="train"):
"""Mnist classification with a multi-layer perceptron."""
if activation == "sigmoid":
activation_op = tf.sigmoid
elif activation == "relu":
activation_op = tf.nn.relu
else:
raise ValueError("{} activation not supported".format(activation))
# Data.
data = mnist_dataset.load_mnist()
data = getattr(data, mode)
images = tf.constant(data.images, dtype=tf.float32, name="MNIST_images")
images = tf.reshape(images, [-1, 28, 28, 1])
labels = tf.constant(data.labels, dtype=tf.int64, name="MNIST_labels")
# Network.
mlp = nn.MLP(list(layers) + [10],
activation=activation_op,
initializers=_nn_initializers)
network = nn.Sequential([nn.BatchFlatten(), mlp])
def build():
indices = tf.random_uniform([batch_size], 0, data.num_examples, tf.int64)
batch_images = tf.gather(images, indices)
batch_labels = tf.gather(labels, indices)
output = network(batch_images)
return _xent_loss(output, batch_labels)
return build
def cifar10(
path, # pylint: disable=invalid-name
conv_channels=None,
linear_layers=None,
batch_norm=True,
batch_size=128,
num_threads=4,
min_queue_examples=1000,
mode="train"):
"""Cifar10 classification with a convolutional network."""
# Data.
_maybe_download_cifar10(path)
# Read images and labels from disk.
if mode == "train":
filenames = [
os.path.join(path, CIFAR10_FOLDER, "data_batch_{}.bin".format(i))
for i in xrange(1, 6)
]
elif mode == "test":
filenames = [os.path.join(path, "test_batch.bin")]
else:
raise ValueError("Mode {} not recognised".format(mode))
depth = 3
height = 32
width = 32
label_bytes = 1
image_bytes = depth * height * width
record_bytes = label_bytes + image_bytes
reader = tf.FixedLengthRecordReader(record_bytes=record_bytes)
_, record = reader.read(tf.train.string_input_producer(filenames))
record_bytes = tf.decode_raw(record, tf.uint8)
label = tf.cast(tf.slice(record_bytes, [0], [label_bytes]), tf.int32)
raw_image = tf.slice(record_bytes, [label_bytes], [image_bytes])
image = tf.cast(tf.reshape(raw_image, [depth, height, width]), tf.float32)
# height x width x depth.
image = tf.transpose(image, [1, 2, 0])
image = tf.div(image, 255)
queue = tf.RandomShuffleQueue(
capacity=min_queue_examples + 3 * batch_size,
min_after_dequeue=min_queue_examples,
dtypes=[tf.float32, tf.int32],
shapes=[image.get_shape(), label.get_shape()])
enqueue_ops = [queue.enqueue([image, label]) for _ in xrange(num_threads)]
tf.train.add_queue_runner(tf.train.QueueRunner(queue, enqueue_ops))
# Network.
def _conv_activation(x): # pylint: disable=invalid-name
return tf.nn.max_pool(tf.nn.relu(x),
ksize=[1, 2, 2, 1],
strides=[1, 2, 2, 1],
padding="SAME")
conv = nn.ConvNet2D(output_channels=conv_channels,
kernel_shapes=[5],
strides=[1],
paddings=[nn.SAME],
activation=_conv_activation,
activate_final=True,
initializers=_nn_initializers,
use_batch_norm=batch_norm)
if batch_norm:
linear_activation = lambda x: tf.nn.relu(nn.BatchNorm()(x))
else:
linear_activation = tf.nn.relu
mlp = nn.MLP(list(linear_layers) + [10],
activation=linear_activation,
initializers=_nn_initializers)
network = nn.Sequential([conv, nn.BatchFlatten(), mlp])
def build():
image_batch, label_batch = queue.dequeue_many(batch_size)
label_batch = tf.reshape(label_batch, [batch_size])
output = network(image_batch)
return _xent_loss(output, label_batch)
return build