model.py
9.38 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
import tensorflow as tf
from ops import *
class DTN(object):
"""Domain Transfer Network for unsupervised cross-domain image generation
Construct discriminator and generator to prepare for training.
"""
def __init__(self, batch_size=100, learning_rate=0.0002, image_size=32, output_size=32,
dim_color=3, dim_fout=100, dim_df=64, dim_gf=64, dim_ff=64):
"""
Args:
learning_rate: (optional) learning rate for discriminator and generator
image_size: (optional) spatial size of input image for discriminator
output_size: (optional) spatial size of image generated by generator
dim_color: (optional) dimension of image color; default is 3 for rgb
dim_fout: (optional) dimension of z (random input vector for generator)
dim_df: (optional) dimension of discriminator's filter in first convolution layer
dim_gf: (optional) dimension of generator's filter in last convolution layer
dim_ff: (optional) dimension of function f's filter in first convolution layer
"""
# hyper parameters
self.batch_size = batch_size
self.learning_rate = learning_rate
self.image_size = image_size
self.output_size = output_size
self.dim_color = dim_color
self.dim_fout = dim_fout
self.dim_df = dim_df
self.dim_gf = dim_gf
self.dim_ff = dim_ff
# placeholder
self.images = tf.placeholder(tf.float32, shape=[batch_size, image_size, image_size, dim_color], name='images')
#self.z = tf.placeholder(tf.float32, shape=[None, dim_z], name='input_for_generator')
# batch normalization layer for discriminator, generator and funtion f
self.d_bn1 = batch_norm(name='d_bn1')
self.d_bn2 = batch_norm(name='d_bn2')
self.d_bn3 = batch_norm(name='d_bn3')
self.g_bn1 = batch_norm(name='g_bn1')
self.g_bn2 = batch_norm(name='g_bn2')
self.g_bn3 = batch_norm(name='g_bn3')
self.g_bn4 = batch_norm(name='g_bn4')
self.f_bn1 = batch_norm(name='f_bn1')
self.f_bn2 = batch_norm(name='f_bn2')
self.f_bn3 = batch_norm(name='f_bn3')
self.f_bn4 = batch_norm(name='f_bn4')
def function_f(self, images, reuse=False):
"""f consistancy
Args:
images: images for domain S and T, of shape (batch_size, image_size, image_size, dim_color)
Returns:
out: output vectors, of shape (batch_size, dim_f_out)
"""
with tf.variable_scope('function_f', reuse=reuse):
h1 = lrelu(conv2d(images, self.dim_ff, name='f_h1')) # (batch_size, 16, 16, 64)
h2 = lrelu(self.d_bn1(conv2d(h1, self.dim_ff*2, name='f_h2'))) # (batch_size, 8, 8 128)
h3 = lrelu(self.d_bn2(conv2d(h2, self.dim_ff*4, name='f_h3'))) # (batch_size, 4, 4, 256)
h4 = lrelu(self.d_bn3(conv2d(h3, self.dim_ff*8, name='f_h4'))) # (batch_size, 2, 2, 512)
h4 = tf.reshape(h4, [self.batch_size,-1])
out = linear(h4, self.dim_fout, name='f_out')
return tf.nn.tanh(out)
def generator(self, z, reuse=False):
"""Generator: Deconvolutional neural network with relu activations.
Last deconv layer does not use batch normalization.
Args:
z: random input vectors, of shape (batch_size, dim_z)
Returns:
out: generated images, of shape (batch_size, image_size, image_size, dim_color)
"""
if reuse:
train = False
else:
train = True
with tf.variable_scope('generator', reuse=reuse):
# spatial size for convolution
s = self.output_size
s2, s4, s8, s16 = s/2, s/4, s/8, s/16 # 32, 16, 8, 4
# project and reshape z
h1= linear(z, s16*s16*self.dim_gf*8, name='g_h1') # (batch_size, 2*2*512)
h1 = tf.reshape(h1, [-1, s16, s16, self.dim_gf*8]) # (batch_size, 2, 2, 512)
h1 = relu(self.g_bn1(h1, train=train))
h2 = deconv2d(h1, [self.batch_size, s8, s8, self.dim_gf*4], name='g_h2') # (batch_size, 4, 4, 256)
h2 = relu(self.g_bn2(h2, train=train))
h3 = deconv2d(h2, [self.batch_size, s4, s4, self.dim_gf*2], name='g_h3') # (batch_size, 8, 8, 128)
h3 = relu(self.g_bn3(h3, train=train))
h4 = deconv2d(h3, [self.batch_size, s2, s2, self.dim_gf], name='g_h4') # (batch_size, 16, 16, 64)
h4 = relu(self.g_bn4(h4, train=train))
out = deconv2d(h4, [self.batch_size, s, s, self.dim_color], name='g_out') # (batch_size, 32, 32, dim_color)
return tf.nn.tanh(out)
def discriminator(self, images, reuse=False):
"""Discrimator: Convolutional neural network with leaky relu activations.
First conv layer does not use batch normalization.
Args:
images: real or fake images of shape (batch_size, image_size, image_size, dim_color)
Returns:
out: scores for whether it is a real image or a fake image, of shape (batch_size,)
"""
with tf.variable_scope('discriminator', reuse=reuse):
# convolution layer
h1 = lrelu(conv2d(images, self.dim_df, name='d_h1')) # (batch_size, 16, 16, 64)
h2 = lrelu(self.d_bn1(conv2d(h1, self.dim_df*2, name='d_h2'))) # (batch_size, 8, 8, 128)
h3 = lrelu(self.d_bn2(conv2d(h2, self.dim_df*4, name='d_h3'))) # (batch_size, 4, 4, 256)
h4 = lrelu(self.d_bn3(conv2d(h3, self.dim_df*8, name='d_h4'))) # (batch_size, 2, 2, 512)
# fully connected layer
h4 = tf.reshape(h4, [self.batch_size, -1])
out = linear(h4, 1, name='d_out') # (batch_size,)
return out
def build_model(self):
# construct generator and discriminator for training phase
self.f_x = self.function_f(self.images)
self.fake_images = self.generator(self.f_x) # (batch_size, 32, 32, 3)
self.logits_real = self.discriminator(self.images) # (batch_size,)
self.logits_fake = self.discriminator(self.fake_images, reuse=True) # (batch_size,)
self.fgf_x = self.function_f(self.fake_images, reuse=True) # (batch_size, dim_f)
# construct generator for test phase
self.sampled_images = self.generator(self.f_x, reuse=True) # (batch_size, 32, 32, 3)
# compute loss
self.d_loss_real = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(self.logits_real, tf.ones_like(self.logits_real)))
self.d_loss_fake = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(self.logits_fake, tf.zeros_like(self.logits_fake)))
self.d_loss = self.d_loss_real + self.d_loss_fake
self.g_loss = tf.reduce_mean(tf.nn.sigmoid_cross_entropy_with_logits(self.logits_fake, tf.ones_like(self.logits_fake)))
self.g_const_loss = tf.reduce_mean(tf.square(self.images - self.fake_images)) # L_TID
self.f_const_loss = tf.reduce_mean(tf.square(self.f_x - self.fgf_x)) # L_CONST
# divide variables for discriminator and generator
t_vars = tf.trainable_variables()
self.d_vars = [var for var in t_vars if 'discriminator' in var.name]
self.g_vars = [var for var in t_vars if 'generator' in var.name]
self.f_vars = [var for var in t_vars if 'function_f' in var.name]
# optimizer for discriminator and generator
with tf.name_scope('optimizer'):
self.d_optimizer_real = tf.train.AdamOptimizer(self.learning_rate, beta1=0.5).minimize(self.d_loss_real, var_list=self.d_vars)
self.d_optimizer_fake = tf.train.AdamOptimizer(self.learning_rate, beta1=0.5).minimize(self.d_loss_fake, var_list=self.d_vars)
self.g_optimizer = tf.train.AdamOptimizer(self.learning_rate, beta1=0.5).minimize(self.g_loss, var_list=self.g_vars+self.f_vars)
self.g_optimizer_const = tf.train.AdamOptimizer(self.learning_rate, beta1=0.5).minimize(self.g_const_loss, var_list=self.g_vars+self.f_vars)
self.f_optimizer_const = tf.train.AdamOptimizer(self.learning_rate, beta1=0.5).minimize(self.f_const_loss, var_list=self.f_vars+self.g_vars)
# summary ops for tensorboard visualization
tf.scalar_summary('d_loss_real', self.d_loss_real)
tf.scalar_summary('d_loss_fake', self.d_loss_fake)
tf.scalar_summary('d_loss', self.d_loss)
tf.scalar_summary('g_loss', self.g_loss)
tf.scalar_summary('g_const_loss', self.g_const_loss)
tf.scalar_summary('f_const_loss', self.f_const_loss)
tf.image_summary('original_images', self.images, max_images=6)
tf.image_summary('sampled_images', self.sampled_images, max_images=6)
for var in tf.trainable_variables():
tf.histogram_summary(var.op.name, var)
self.summary_op = tf.merge_all_summaries()
self.saver = tf.train.Saver()