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记录这篇文章,一来可以学习下GAN概论,二来代码完整可用,需要的话可就此代码改进新模型
目录
资源说明
链接:https://pan.baidu.com/s/16fAdMkbXq-C9ZNU5tHnBIA
提取码:hndh
GAN_TRAIN为训练一代后的文件,附带结果图和模型文件;GAN_RAW为初始文件,可拿着就可以使用,较小
checkpoint | 保存点文件,GAN_RAW.rar里为空,GAN_TRAIN.rar里有一次迭代的模型文件 |
data | 数据集文件 |
logs | 日志文件,GAN_RAW.rar里为空,GAN_TRAIN.rar里有一次迭代的日志文件 |
results | 结果文件,GAN_RAW.rar里为空,GAN_TRAIN.rar里有一次迭代的输出图像文件 |
CGAN.py | 条件生成式对抗网络 |
GAN.py | 生成式对抗网络 |
main.py | 运行主文件 |
utils.py和ops.py | 配置以及工具文件 |
GAN与CGAN
生成式模型的意义:1.处理高维数据和复杂概率分布能力的检测。2.面临缺乏或缺失数据时,使用生成模型补足,3.可输出多模态结果
原理:
核心思想来自于博弈论的纳什均衡,
简言之,即生成网络生成图片,判别网络判别图片是否为真,生成网络的目的尽可能学习真实数据分布,让判别网络无法区分,而判别网络则是二分类网络,尽可能区分图片是否为真。相当于二者进行博弈,然后不断提升水平
更专业的原理图(有需求再仔细研究吧):
fashion-mnist数据集共10类别(T恤,帽子等)类比于MNIST手写数据集
利用GAN即生成式对抗网络,可生成如下图片:
而CGAN即条件生成式对抗网络,可实现条件式生成,比如分类别生成(所以生成器需要生成与条件匹配的,判别器需要判别图像且符合条件的):
源码及运行效果:
GAN.py:
#-*- coding: utf-8 -*-
"""
Most codes from
https://github.com/carpedm20/DCGAN-tensorflow
"""
from __future__ import division
import time
from GAN_PACKAGE.ops import *
from GAN_PACKAGE.utils import *
class GAN(object):
model_name = "GAN" #模型名称,checkpoint文件夹名称
""" 对实例的属性进行初始化 """
def __init__(self, sess, epoch, batch_size, z_dim, dataset_name, checkpoint_dir, result_dir, log_dir):
self.sess = sess
self.dataset_name = dataset_name
self.checkpoint_dir = checkpoint_dir
self.result_dir = result_dir
self.log_dir = log_dir
self.epoch = epoch
self.batch_size = batch_size
# 参数值
self.input_height = 28
self.input_width = 28
self.output_height = 28
self.output_width = 28
self.z_dim = z_dim # 噪声矢量的维度
self.c_dim = 1 # 由于fashion是灰度图,因此维度为1
self.learning_rate = 0.0002
self.beta1 = 0.5
self.sample_num = 64 # 设置保存生成图片的数量
# 载入数据
self.data_X, self.data_y = load_mnist(self.dataset_name)
# 每一个epoch中batch数量
self.num_batches = len(self.data_X) // self.batch_size
""" 搭建判别器 """
def discriminator(self, x, is_training=True, reuse=False):
with tf.variable_scope("discriminator", reuse=reuse):
net = lrelu(conv2d(x, 64, 4, 4, 2, 2, name='d_conv1'))
net = lrelu(bn(conv2d(net, 128, 4, 4, 2, 2, name='d_conv2'), is_training=is_training, scope='d_bn2'))
net = tf.reshape(net, [self.batch_size, -1])
net = lrelu(bn(linear(net, 1024, scope='d_fc3'), is_training=is_training, scope='d_bn3'))
out_logit = linear(net, 1, scope='d_fc4')
out = tf.nn.sigmoid(out_logit)
return out, out_logit, net
""" 搭建生成器 """
def generator(self, z, is_training=True, reuse=False):
with tf.variable_scope("generator", reuse=reuse):
net = tf.nn.relu(bn(linear(z, 1024, scope='g_fc1'), is_training=is_training, scope='g_bn1'))
net = tf.nn.relu(bn(linear(net, 128 * 7 * 7, scope='g_fc2'), is_training=is_training, scope='g_bn2'))
net = tf.reshape(net, [self.batch_size, 7, 7, 128])
net = tf.nn.relu(
bn(deconv2d(net, [self.batch_size, 14, 14, 64], 4, 4, 2, 2, name='g_dc3'), is_training=is_training,
scope='g_bn3'))
out = tf.nn.sigmoid(deconv2d(net, [self.batch_size, 28, 28, 1], 4, 4, 2, 2, name='g_dc4'))
return out
""" 构建模型 """
def build_model(self):
image_dims = [self.input_height, self.input_width, self.c_dim]
bs = self.batch_size
""" 输入 """
# 图像
self.inputs = tf.placeholder(tf.float32, [bs] + image_dims, name='real_images')
# 噪声矢量
self.z = tf.placeholder(tf.float32, [bs, self.z_dim], name='z')
""" 损失函数 """
# 判别器对于真实图像的输出
D_real, D_real_logits, _ = self.discriminator(self.inputs, is_training=True, reuse=False)
# 判别器对于生成图像的输出
G = self.generator(self.z, is_training=True, reuse=False)
D_fake, D_fake_logits, _ = self.discriminator(G, is_training=True, reuse=True)
# 判别器的损失函数
d_loss_real = tf.reduce_mean(
tf.nn.sigmoid_cross_entropy_with_logits(logits=D_real_logits, labels=tf.ones_like(D_real)))
d_loss_fake = tf.reduce_mean(
tf.nn.sigmoid_cross_entropy_with_logits(logits=D_fake_logits, labels=tf.zeros_like(D_fake)))
self.d_loss = d_loss_real + d_loss_fake
# 生成器的损失函数
self.g_loss = tf.reduce_mean(
tf.nn.sigmoid_cross_entropy_with_logits(logits=D_fake_logits, labels=tf.ones_like(D_fake)))
# 可训练变量
t_vars = tf.trainable_variables()
d_vars = [var for var in t_vars if 'd_' in var.name]
g_vars = [var for var in t_vars if 'g_' in var.name]
# 优化器
with tf.control_dependencies(tf.get_collection(tf.GraphKeys.UPDATE_OPS)):
self.d_optim = tf.train.AdamOptimizer(self.learning_rate, beta1=self.beta1) \
.minimize(self.d_loss, var_list=d_vars)
self.g_optim = tf.train.AdamOptimizer(self.learning_rate*5, beta1=self.beta1) \
.minimize(self.g_loss, var_list=g_vars)
# 生成图像
self.fake_images = self.generator(self.z, is_training=False, reuse=True)
d_loss_real_sum = tf.summary.scalar("d_loss_real", d_loss_real)
d_loss_fake_sum = tf.summary.scalar("d_loss_fake", d_loss_fake)
d_loss_sum = tf.summary.scalar("d_loss", self.d_loss)
g_loss_sum = tf.summary.scalar("g_loss", self.g_loss)
self.g_sum = tf.summary.merge([d_loss_fake_sum, g_loss_sum])
self.d_sum = tf.summary.merge([d_loss_real_sum, d_loss_sum])
""" 执行训练 """
def train(self):
# 变量的初始化
tf.global_variables_initializer().run()
# 图(graph)的输入
self.sample_z = np.random.uniform(-1, 1, size=(self.batch_size , self.z_dim))
self.saver = tf.train.Saver()
self.writer = tf.summary.FileWriter(self.log_dir + '/' + self.model_name, self.sess.graph)
# 载入checkpoint
could_load, checkpoint_counter = self.load(self.checkpoint_dir)
if could_load:
start_epoch = (int)(checkpoint_counter / self.num_batches)
start_batch_id = checkpoint_counter - start_epoch * self.num_batches
counter = checkpoint_counter
print(" [*] Load SUCCESS")
else:
start_epoch = 0
start_batch_id = 0
counter = 1
print(" [!] Load failed...")
# epoch迭代
start_time = time.time()
for epoch in range(start_epoch, self.epoch):
# 获取批量数据
for idx in range(start_batch_id, self.num_batches):
batch_images = self.data_X[idx*self.batch_size:(idx+1)*self.batch_size]
batch_z = np.random.uniform(-1, 1, [self.batch_size, self.z_dim]).astype(np.float32)
# 更新判别器
_, summary_str, d_loss = self.sess.run([self.d_optim, self.d_sum, self.d_loss],
feed_dict={self.inputs: batch_images, self.z: batch_z})
self.writer.add_summary(summary_str, counter)
# 更新生成器
_, summary_str, g_loss = self.sess.run([self.g_optim, self.g_sum, self.g_loss], feed_dict={self.z: batch_z})
self.writer.add_summary(summary_str, counter)
# 显示训练状态
counter += 1
print("Epoch: [%2d] [%4d/%4d] time: %4.4f, d_loss: %.8f, g_loss: %.8f" \
% (epoch, idx, self.num_batches, time.time() - start_time, d_loss, g_loss))
# 每50步保存训练结果
if np.mod(counter, 50) == 0:
samples = self.sess.run(self.fake_images, feed_dict={self.z: self.sample_z})
tot_num_samples = min(self.sample_num, self.batch_size)
manifold_h = int(np.floor(np.sqrt(tot_num_samples)))
manifold_w = int(np.floor(np.sqrt(tot_num_samples)))
save_images(samples[:manifold_h * manifold_w, :, :, :], [manifold_h, manifold_w],
'./' + check_folder(self.result_dir + '/' + self.model_dir) + '/' + self.model_name + '_train_{:02d}_{:04d}.png'.format(
epoch, idx))
start_batch_id = 0
# 保存模型
self.save(self.checkpoint_dir, counter)
# 当前结果的可视化
self.visualize_results(epoch)
# 保存最终模型
self.save(self.checkpoint_dir, counter)
""" 定义功能函数 """
def visualize_results(self, epoch):
tot_num_samples = min(self.sample_num, self.batch_size)
image_frame_dim = int(np.floor(np.sqrt(tot_num_samples)))
z_sample = np.random.uniform(-1, 1, size=(self.batch_size, self.z_dim))
samples = self.sess.run(self.fake_images, feed_dict={self.z: z_sample})
save_images(samples[:image_frame_dim * image_frame_dim, :, :, :], [image_frame_dim, image_frame_dim],
check_folder(self.result_dir + '/' + self.model_dir) + '/' + self.model_name + '_epoch%03d' % epoch + '_test_all_classes.png')
@property
def model_dir(self):
return "{}_{}_{}_{}".format(
self.model_name, self.dataset_name,
self.batch_size, self.z_dim)
def save(self, checkpoint_dir, step):
checkpoint_dir = os.path.join(checkpoint_dir, self.model_dir, self.model_name)
if not os.path.exists(checkpoint_dir):
os.makedirs(checkpoint_dir)
self.saver.save(self.sess,os.path.join(checkpoint_dir, self.model_name+'.model'), global_step=step)
def load(self, checkpoint_dir):
import re
print(" [*] Reading checkpoints...")
checkpoint_dir = os.path.join(checkpoint_dir, self.model_dir, self.model_name)
ckpt = tf.train.get_checkpoint_state(checkpoint_dir)
if ckpt and ckpt.model_checkpoint_path:
ckpt_name = os.path.basename(ckpt.model_checkpoint_path)
self.saver.restore(self.sess, os.path.join(checkpoint_dir, ckpt_name))
counter = int(next(re.finditer("(\d+)(?!.*\d)",ckpt_name)).group(0))
print(" [*] Success to read {}".format(ckpt_name))
return True, counter
else:
print(" [*] Failed to find a checkpoint")
return False, 0
迭代一次之后:
可以在result中看到结果图片
可以看到,前几次图片迭代时图片还基本为空,逐渐就更加自然了。