本文最后更新于:14 天前
代码:
#!/usr/bin/env python
# -*- coding: utf-8 -*-
# @Time : 2018/9/4 16:29
# @Author : Seven
# @Site :
# @File : DCGAN.py
# @Software: PyCharm
# TODO: 导入环境
import numpy as np
import tensorflow as tf
import matplotlib.pyplot as plt
from tensorflow.examples.tutorials.mnist import input_data
# TODO:数据准备
mnist = input_data.read_data_sets('data')
# TODO:获得输入数据
def get_inputs(noise_dim, image_height, image_width, image_depth):
# 真实数据
inputs_real = tf.placeholder(tf.float32, [None, image_height, image_width, image_depth], name='inputs_real')
# 噪声数据
inputs_noise = tf.placeholder(tf.float32, [None, noise_dim], name='inputs_noise')
return inputs_real, inputs_noise
# TODO:生成器
def get_generator(noise_img, output_dim, is_train=True, alpha=0.01):
with tf.variable_scope("generator", reuse=(not is_train)):
# 100 x 1 to 4 x 4 x 512
# 全连接层
layer1 = tf.layers.dense(noise_img, 4 * 4 * 512)
layer1 = tf.reshape(layer1, [-1, 4, 4, 512])
# batch normalization
layer1 = tf.layers.batch_normalization(layer1, training=is_train)
# Leaky ReLU
layer1 = tf.maximum(alpha * layer1, layer1)
# dropout
layer1 = tf.nn.dropout(layer1, keep_prob=0.8)
# 4 x 4 x 512 to 7 x 7 x 256
layer2 = tf.layers.conv2d_transpose(layer1, 256, 4, strides=1, padding='valid')
layer2 = tf.layers.batch_normalization(layer2, training=is_train)
layer2 = tf.maximum(alpha * layer2, layer2)
layer2 = tf.nn.dropout(layer2, keep_prob=0.8)
# 7 x 7 256 to 14 x 14 x 128
layer3 = tf.layers.conv2d_transpose(layer2, 128, 3, strides=2, padding='same')
layer3 = tf.layers.batch_normalization(layer3, training=is_train)
layer3 = tf.maximum(alpha * layer3, layer3)
layer3 = tf.nn.dropout(layer3, keep_prob=0.8)
# 14 x 14 x 128 to 28 x 28 x 1
logits = tf.layers.conv2d_transpose(layer3, output_dim, 3, strides=2, padding='same')
# MNIST原始数据集的像素范围在0-1,这里的生成图片范围为(-1,1)
# 因此在训练时,记住要把MNIST像素范围进行resize
outputs = tf.tanh(logits)
return outputs
# TODO:判别器
def get_discriminator(inputs_img, reuse=False, alpha=0.01):
with tf.variable_scope("discriminator", reuse=reuse):
# 28 x 28 x 1 to 14 x 14 x 128
# 第一层不加入BN
layer1 = tf.layers.conv2d(inputs_img, 128, 3, strides=2, padding='same')
layer1 = tf.maximum(alpha * layer1, layer1)
layer1 = tf.nn.dropout(layer1, keep_prob=0.8)
# 14 x 14 x 128 to 7 x 7 x 256
layer2 = tf.layers.conv2d(layer1, 256, 3, strides=2, padding='same')
layer2 = tf.layers.batch_normalization(layer2, training=True)
layer2 = tf.maximum(alpha * layer2, layer2)
layer2 = tf.nn.dropout(layer2, keep_prob=0.8)
# 7 x 7 x 256 to 4 x 4 x 512
layer3 = tf.layers.conv2d(layer2, 512, 3, strides=2, padding='same')
layer3 = tf.layers.batch_normalization(layer3, training=True)
layer3 = tf.maximum(alpha * layer3, layer3)
layer3 = tf.nn.dropout(layer3, keep_prob=0.8)
# 4 x 4 x 512 to 4*4*512 x 1
flatten = tf.reshape(layer3, (-1, 4 * 4 * 512))
logits = tf.layers.dense(flatten, 1)
outputs = tf.sigmoid(logits)
return logits, outputs
# TODO: 目标函数
def get_loss(inputs_real, inputs_noise, image_depth, smooth=0.1):
g_outputs = get_generator(inputs_noise, image_depth, is_train=True)
d_logits_real, d_outputs_real = get_discriminator(inputs_real)
d_logits_fake, d_outputs_fake = get_discriminator(g_outputs, reuse=True)
# 计算Loss
g_loss = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_fake,
labels=tf.ones_like(d_outputs_fake) * (1 - smooth)))
d_loss_real = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_real,
labels=tf.ones_like(d_outputs_real) * (
1 - smooth)))
d_loss_fake = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(logits=d_logits_fake,
labels=tf.zeros_like(d_outputs_fake)))
d_loss = tf.add(d_loss_real, d_loss_fake)
return g_loss, d_loss
# TODO:优化器
def get_optimizer(g_loss, d_loss, learning_rate=0.001):
train_vars = tf.trainable_variables()
g_vars = [var for var in train_vars if var.name.startswith("generator")]
d_vars = [var for var in train_vars if var.name.startswith("discriminator")]
# Optimizer
with tf.control_dependencies(tf.get_collection(tf.GraphKeys.UPDATE_OPS)):
g_opt = tf.train.AdamOptimizer(learning_rate).minimize(g_loss, var_list=g_vars)
d_opt = tf.train.AdamOptimizer(learning_rate).minimize(d_loss, var_list=d_vars)
return g_opt, d_opt
# 显示图片
def plot_images(samples):
fig, axes = plt.subplots(nrows=5, ncols=5, sharex=True, sharey=True, figsize=(7, 7))
for img, ax in zip(samples, axes.flatten()):
ax.imshow(img.reshape((28, 28)), cmap='Greys_r')
ax.get_xaxis().set_visible(False)
ax.get_yaxis().set_visible(False)
fig.tight_layout(pad=0)
plt.show()
def show_generator_output(sess, n_images, inputs_noise, output_dim):
noise_shape = inputs_noise.get_shape().as_list()[-1]
# 生成噪声图片
examples_noise = np.random.uniform(-1, 1, size=[n_images, noise_shape])
samples = sess.run(get_generator(inputs_noise, output_dim, False),
feed_dict={inputs_noise: examples_noise})
result = np.squeeze(samples, -1)
return result
# TODO:开始训练
# 定义参数
batch_size = 64
noise_size = 100
epochs = 5
n_samples = 25
learning_rate = 0.001
def train(noise_size, data_shape, batch_size, n_samples):
# 存储loss
losses = []
steps = 0
inputs_real, inputs_noise = get_inputs(noise_size, data_shape[1], data_shape[2], data_shape[3])
g_loss, d_loss = get_loss(inputs_real, inputs_noise, data_shape[-1])
print("FUNCTION READY!!")
g_train_opt, d_train_opt = get_optimizer(g_loss, d_loss, learning_rate)
print("TRAINING....")
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
# 迭代epoch
for e in range(epochs):
for batch_i in range(mnist.train.num_examples // batch_size):
steps += 1
batch = mnist.train.next_batch(batch_size)
batch_images = batch[0].reshape((batch_size, data_shape[1], data_shape[2], data_shape[3]))
# scale to -1, 1
batch_images = batch_images * 2 - 1
# noise
batch_noise = np.random.uniform(-1, 1, size=(batch_size, noise_size))
# run optimizer
sess.run(g_train_opt, feed_dict={inputs_real: batch_images,
inputs_noise: batch_noise})
sess.run(d_train_opt, feed_dict={inputs_real: batch_images,
inputs_noise: batch_noise})
if steps % 101 == 0:
train_loss_d = d_loss.eval({inputs_real: batch_images,
inputs_noise: batch_noise})
train_loss_g = g_loss.eval({inputs_real: batch_images,
inputs_noise: batch_noise})
losses.append((train_loss_d, train_loss_g))
print("Epoch {}/{}....".format(e + 1, epochs),
"Discriminator Loss: {:.4f}....".format(train_loss_d),
"Generator Loss: {:.4f}....".format(train_loss_g))
if e % 1 == 0:
# 显示图片
samples = show_generator_output(sess, n_samples, inputs_noise, data_shape[-1])
plot_images(samples)
with tf.Graph().as_default():
train(noise_size, [-1, 28, 28, 1], batch_size, n_samples)
print("OPTIMIZER END!!")
执行结果:
Epoch 4/5.... Discriminator Loss: 0.4584.... Generator Loss: 4.8776....
Epoch 4/5.... Discriminator Loss: 0.4315.... Generator Loss: 2.9278....
Epoch 4/5.... Discriminator Loss: 0.5317.... Generator Loss: 3.4315....
Epoch 4/5.... Discriminator Loss: 0.6342.... Generator Loss: 2.7376....
Epoch 4/5.... Discriminator Loss: 0.4312.... Generator Loss: 3.9016....
Epoch 4/5.... Discriminator Loss: 0.5498.... Generator Loss: 2.3418....
Epoch 4/5.... Discriminator Loss: 0.4807.... Generator Loss: 3.4065....
Epoch 4/5.... Discriminator Loss: 0.5360.... Generator Loss: 2.2658....
Epoch 4/5.... Discriminator Loss: 0.4612.... Generator Loss: 2.8166....
Epoch 5/5.... Discriminator Loss: 0.4784.... Generator Loss: 2.9896....
Epoch 5/5.... Discriminator Loss: 0.7368.... Generator Loss: 2.1130....
Epoch 5/5.... Discriminator Loss: 0.4192.... Generator Loss: 3.9733....
Epoch 5/5.... Discriminator Loss: 0.4998.... Generator Loss: 2.1577....
Epoch 5/5.... Discriminator Loss: 0.4693.... Generator Loss: 3.1395....
Epoch 5/5.... Discriminator Loss: 0.3946.... Generator Loss: 4.0385....
Epoch 5/5.... Discriminator Loss: 0.4807.... Generator Loss: 3.8975....
Epoch 5/5.... Discriminator Loss: 0.4703.... Generator Loss: 3.6105....
OPTIMIZER END!!
生成的图像:
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