生成对抗网络DCGAN+Tensorflow代码学习笔记（三）----ops.py

ops.py主要定义了一些变量连接的函数、批处理规范化的函数、卷积函数、解卷积函数、激励函数、线性运算函数。

import math
import numpy as np
import tensorflow as tf
#导入tensorflow.python.framework模块，包含了tensorflow中图、张量等的定义操作
from tensorflow.python.framework import ops

from utils import *

try:
image_summary = tf.image_summary
scalar_summary = tf.scalar_summary
histogram_summary = tf.histogram_summary
merge_summary = tf.merge_summary
SummaryWriter = tf.train.SummaryWriter
except:
image_summary = tf.summary.image
scalar_summary = tf.summary.scalar
histogram_summary = tf.summary.histogram
merge_summary = tf.summary.merge
SummaryWriter = tf.summary.FileWriter
#连接多个tensor
if "concat_v2" in dir(tf):
def concat(tensors, axis, *args, **kwargs):
return tf.concat_v2(tensors, axis, *args, **kwargs)
else:
def concat(tensors, axis, *args, **kwargs):
return tf.concat(tensors, axis, *args, **kwargs)
#函数批处理规范化
class batch_norm(object):
def __init__(self, epsilon=1e-5, momentum = 0.9, name="batch_norm"):
with tf.variable_scope(name):
self.epsilon = epsilon
self.momentum = momentum
self.name = name

def __call__(self, x, train=True):
return tf.contrib.layers.batch_norm(x,
decay=self.momentum,
updates_collections=None,
epsilon=self.epsilon,
scale=True,
is_training=train,
scope=self.name)
#定义conv_cond_concat(x,y)函数。连接x,y与Int32型的[x_shapes[0], x_shapes[1], x_shapes[2], y_shapes[3]]维度的张量乘积。
def conv_cond_concat(x, y):
"""Concatenate conditioning vector on feature map axis."""
x_shapes = x.get_shape()
y_shapes = y.get_shape()
return concat([
x, y*tf.ones([x_shapes[0], x_shapes[1], x_shapes[2], y_shapes[3]])], 3)
#卷积层
def conv2d(input_, output_dim,
k_h=5, k_w=5, d_h=2, d_w=2, stddev=0.02,
name="conv2d"):
with tf.variable_scope(name):
w = tf.get_variable('w', [k_h, k_w, input_.get_shape()[-1], output_dim],
initializer=tf.truncated_normal_initializer(stddev=stddev))
conv = tf.nn.conv2d(input_, w, strides=[1, d_h, d_w, 1], padding='SAME')

biases = tf.get_variable('biases', [output_dim], initializer=tf.constant_initializer(0.0))
conv = tf.reshape(tf.nn.bias_add(conv, biases), conv.get_shape())

return conv
#反卷积层
def deconv2d(input_, output_shape,
k_h=5, k_w=5, d_h=2, d_w=2, stddev=0.02,
name="deconv2d", with_w=False):
with tf.variable_scope(name):
# filter : [height, width, output_channels, in_channels]
w = tf.get_variable('w', [k_h, k_w, output_shape[-1], input_.get_shape()[-1]],
initializer=tf.random_normal_initializer(stddev=stddev))

try:
deconv = tf.nn.conv2d_transpose(input_, w, output_shape=output_shape,
strides=[1, d_h, d_w, 1])

# Support for verisons of TensorFlow before 0.7.0
except AttributeError:
deconv = tf.nn.deconv2d(input_, w, output_shape=output_shape,
strides=[1, d_h, d_w, 1])

biases = tf.get_variable('biases', [output_shape[-1]], initializer=tf.constant_initializer(0.0))
deconv = tf.reshape(tf.nn.bias_add(deconv, biases), deconv.get_shape())

if with_w:
return deconv, w, biases
else:
return deconv
#定义一个lrelu激励函数
def lrelu(x, leak=0.2, name="lrelu"):
return tf.maximum(x, leak*x)
#进行线性运算，获取一个随机正态分布矩阵，获取初始偏置值，如果with_w为真，则返回xw+b，权值w和偏置值b；否则返回xw+b。
def linear(input_, output_size, scope=None, stddev=0.02, bias_start=0.0, with_w=False):
shape = input_.get_shape().as_list()

with tf.variable_scope(scope or "Linear"):
matrix = tf.get_variable("Matrix", [shape[1], output_size], tf.float32,
tf.random_normal_initializer(stddev=stddev))
bias = tf.get_variable("bias", [output_size],
initializer=tf.constant_initializer(bias_start))
if with_w:
return tf.matmul(input_, matrix) + bias, matrix, bias
else:
return tf.matmul(input_, matrix) + bias