import os
import numpy as np
import time
import tensorflow as tf
from PIL import Image
import matplotlib.pyplot as plt
def get_all_files(file_path):
"""
获取图片路径及其标签
:param file_path: a sting, 图片所在目录
:param is_random: True or False, 是否乱序
:return:
"""
image_list = []
label_list = []
cat_count = 0
dog_count = 0
for item in os.listdir(file_path):
item_path = file_path + '\\' + item
item_label = item.split('.')[0] # 文件名形如 cat.0.jpg,只需要取第一个
if os.path.isfile(item_path):
image_list.append(item_path)
else:
raise ValueError('文件夹中有非文件项.')
if item_label == 'cat': # 猫标记为'0'
label_list.append(0)
cat_count += 1
else: # 狗标记为'1'
label_list.append(1)
dog_count += 1
print('数据集中有%d只猫,%d只狗.' % (cat_count, dog_count))
image_list = np.asarray(image_list)
label_list = np.asarray(label_list)
# 乱序文件
rnd_index = np.arange(len(image_list))
np.random.shuffle(rnd_index)
image_list = image_list[rnd_index]
label_list = label_list[rnd_index]
return image_list, label_list
def get_batch(image,lable, image_size_w,image_size_h, batch_size, capacity):
"""
获取训练批次
:param train_list: 2-D list, [image_list, label_list]
:param image_size: a int, 训练图像大小
:param batch_size: a int, 每个批次包含的样本数量
:param capacity: a int, 队列容量
:param is_random: True or False, 是否乱序
:return:
"""
image =tf.cast(image,tf.string)
lable =tf.cast(lable,tf.int32)
intput_queue = tf.train.slice_input_producer([image,lable])
# 从路径中读取图片
image_train = tf.read_file(intput_queue[0])
image_train = tf.image.decode_jpeg(image_train, channels=3) # 这里是jpg格式
image_train = tf.image.resize_images(image_train, [image_size_h, image_size_w])
image_train = tf.cast(image_train, tf.float32) / 255. # 转换数据类型并归一化
# 图片标签
label_train = intput_queue[1]
# 获取批次
image_train_batch, label_train_batch = tf.train.shuffle_batch([image_train, label_train],
batch_size=batch_size,
capacity=capacity,
min_after_dequeue=100,
num_threads=2)
return image_train_batch, label_train_batch
def cnn_inference(images, batch_size, n_classes):
# 第一层的卷积层conv1,卷积核为3X3,有16个
with tf.variable_scope('conv1') as scope:
# 建立weights和biases的共享变量
# conv1, shape = [kernel size, kernel size, channels, kernel numbers]
weights = tf.get_variable('weights',
shape=[3, 3, 3, 16],
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=0.1, dtype=tf.float32))
biases = tf.get_variable('biases',
shape=[16],
dtype=tf.float32,
initializer=tf.constant_initializer(0.1))
conv = tf.nn.conv2d(images,
weights,
strides=[1, 1, 1, 1],
padding='SAME')
pre_activation = tf.nn.bias_add(conv, biases) # 加入偏差
conv1 = tf.nn.relu(pre_activation, name=scope.name) # 加上激活函数非线性化处理,且是在conv1的命名空间
# 第一层的池化层pool1和规范化norm1(特征缩放)
with tf.variable_scope('pooling1_lrn') as scope:
pool1 = tf.nn.max_pool(conv1,
ksize=[1, 2, 2, 1],
strides=[1, 2, 2, 1],
padding='SAME',
name='pooling1')
norm1 = tf.nn.lrn(pool1,
depth_radius=4,
bias=1.0,
alpha=0.001 / 9.0,
beta=0.75,
name='norm1')
# 第二层的卷积层cov2
with tf.variable_scope('conv2') as scope:
weights = tf.get_variable('weights',
shape=[3, 3, 16, 16], # 这里只有第三位数字16需要等于上一层的tensor维度
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=0.1,dtype=tf.float32))
biases = tf.get_variable('biases',
shape=[16],
dtype=tf.float32,
initializer=tf.constant_initializer(0.1))
conv = tf.nn.conv2d(norm1, weights, strides=[1, 1, 1, 1], padding='SAME')
pre_activation = tf.nn.bias_add(conv, biases)
conv2 = tf.nn.relu(pre_activation, name='conv2')
# 第二层的池化层pool2和规范化norm2
with tf.variable_scope('pooling2_lrn') as scope:
norm2 = tf.nn.lrn(conv2,
depth_radius=4,
bias=1.0,
alpha=0.001 / 9.0,
beta=0.75,
name='norm2')
pool2 = tf.nn.max_pool(norm2,
ksize=[1, 2, 2, 1],
strides=[1, 1, 1, 1],
padding='SAME',
name='pooling2')
# 这里选择了先规范化再池化
with tf.variable_scope('local3') as scope:
# flatten-把卷积过的多维tensor拉平成二维张量(矩阵)
reshape = tf.reshape(pool2, shape=[batch_size, -1]) # batch_size表明了有多少个样本
dim = reshape.get_shape()[1].value # 知道-1(代表任意)这里具体是多少个
weights = tf.get_variable('weights',
shape=[dim, 256], # 连接256个神经元
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=0.005,dtype=tf.float32))
biases = tf.get_variable('biases',
shape=[256],
dtype=tf.float32,
initializer=tf.constant_initializer(0.1))
local3 = tf.nn.relu(tf.matmul(reshape, weights) + biases, name=scope.name) # 矩阵相乘加上bias
# 第四层为全连接层local4
with tf.variable_scope('local4') as scope:
weights = tf.get_variable('weights',
shape=[256, 512], # 再连接512个神经元
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=0.005,dtype=tf.float32))
biases = tf.get_variable('biases',
shape=[512],
dtype=tf.float32,
initializer=tf.constant_initializer(0.1))
local4 = tf.nn.relu(tf.matmul(local3, weights) + biases, name='local4')
# 第六层为输出层softmax_linear
with tf.variable_scope('softmax_linear') as scope:
weights = tf.get_variable('weights',
shape=[512, n_classes],
dtype=tf.float32,
initializer=tf.truncated_normal_initializer(stddev=0.005,dtype=tf.float32))
biases = tf.get_variable('biases',
shape=[n_classes],
dtype=tf.float32,
initializer=tf.constant_initializer(0.1))
softmax_linear = tf.add(tf.matmul(local4, weights), biases, name='softmax_linear')
# 这里只是命名为softmax_linear,真正的softmax函数放在下面的losses函数里面和交叉熵结合在一起了,这样可以提高运算速度。
# softmax_linear的行数=local4的行数,列数=weights的列数=bias的行数=需要分类的个数
# 经过softmax函数用于分类过程中,它将多个神经元的输出,映射到(0,1)区间内,可以看成概率来理解
return softmax_linear
def losses(logits, labels):
with tf.variable_scope('loss') as scope:
# 下面把交叉熵和softmax合到一起写是为了通过spares提高计算速度
cross_entropy = tf.nn.sparse_softmax_cross_entropy_with_logits(logits=logits, labels=labels, name='loss_per_eg')
loss = tf.reduce_mean(cross_entropy, name='loss') # 求所有样本的平均loss
tf.summary.scalar(scope.name + '/loss', loss)
return loss
def training(loss, learning_rate):
with tf.name_scope('optimizer'):
optimizer = tf.train.AdamOptimizer(learning_rate=learning_rate)
global_step = tf.Variable(0, name='global_step', trainable=False)
train_op = optimizer.minimize(loss, global_step=global_step)
return train_op
def evaluation(logits, labels):
with tf.variable_scope('accuracy') as scope:
correct = tf.nn.in_top_k(logits, labels, 1)
correct = tf.cast(correct, tf.float16)
accuracy = tf.reduce_mean(correct)
tf.summary.scalar(scope.name + '/accuracy', accuracy)
return accuracy
def train():
N_CLASSES = 2 # 猫和狗
IMG_W = 208 # resize图像,太大的话训练时间久
IMG_H = 208
BATCH_SIZE = 64
CAPACITY = 2000
MAX_STEP = 15000 # 一般5K~10k####################################
learning_rate = 0.00001 # 一般小于0.0001
train_dir = 'E:/python ese/cat_dog/data/train/train'
logs_train_dir = 'E:/python ese/cat_dog/log/' # 记录训练过程与保存模型
train, train_label = get_all_files(train_dir)
train_batch, train_label_batch = get_batch(train,
train_label,
IMG_W,
IMG_H,
BATCH_SIZE,
CAPACITY)
train_logits = cnn_inference(train_batch, BATCH_SIZE, N_CLASSES)
train_loss = losses(train_logits, train_label_batch)
train_op = training(train_loss, learning_rate)
train_acc = evaluation(train_logits, train_label_batch)
summary_op = tf.summary.merge_all()
# 可视化为了画折线图
step_list = list(range(15000))
cnn_list1 = []
cnn_list2 = []
fig = plt.figure() # 建立可视化图像框
ax = fig.add_subplot(1, 1, 1) # 子图总行数、列数,位置
ax.yaxis.grid(True)
ax.set_title('cnn_accuracy ', fontsize=14, y=1.02)
ax.set_xlabel('step')
ax.set_ylabel('accuracy')
bx = fig.add_subplot(1, 2, 2)
bx.yaxis.grid(True)
bx.set_title('cnn_loss ', fontsize=14, y=1.02)
bx.set_xlabel('step')
bx.set_ylabel('loss')
# 初始化,如果存在变量则是必不可少的操作
with tf.Session() as sess:
sess.run(tf.global_variables_initializer())
# 产生一个writer来写log文件
train_writer = tf.summary.FileWriter(logs_train_dir, sess.graph)
# 产生一个saver来存储训练好的模型
saver = tf.train.Saver()
# 队列监控
# batch训练法用到了队列,不想用队列也可以用placeholder
coord = tf.train.Coordinator()
threads = tf.train.start_queue_runners(sess=sess, coord=coord)
try:
# 执行MAX_STEP步的训练,一步一个batch
for step in np.arange(MAX_STEP):
if coord.should_stop():
break
# 启动以下操作节点,这里不能用train_op,因为它在第二次迭代是None,会导致session出错,改为_
_op, tra_loss, tra_acc = sess.run([train_op, train_loss, train_acc])
# 每隔50步打印一次当前的loss以及acc,同时记录log,写入writer
if step % 50 == 0:
print('Step %d, train loss = %.2f, train accuracy = %.2f%%' % (step, tra_loss, tra_acc * 100.0))
summary_str = sess.run(summary_op)
train_writer.add_summary(summary_str, step)
# 每隔100步画个图
if step % 1 == 0:
cnn_list1.append(tra_acc)
cnn_list2.append(tra_loss)
# 每隔5000步,保存一次训练好的模型
if step % 5000 == 0 or (step + 1) == MAX_STEP:
checkpoint_path = os.path.join(logs_train_dir, 'model.ckpt')
saver.save(sess, checkpoint_path, global_step=step)
ax.plot(step_list, cnn_list1)
bx.plot(step_list, cnn_list2)
plt.show()
except tf.errors.OutOfRangeError:
print('Done training -- epoch limit reached')
finally:
coord.request_stop()
def get_one_image(train):
'''Randomly pick one image from training data
Return: ndarray
'''
n = len(train)
ind = np.random.randint(0, n)
img_dir = train[ind]
image = Image.open(img_dir)
plt.imshow(image)
image = image.resize([208, 208])
image = np.array(image)
return image
def evaluate_one_image():
train_dir = 'E:/python ese/cat_dog/data/test1/test1/'
train, train_label = get_all_files(train_dir)
image_array = get_one_image(train)
with tf.Graph().as_default():
BATCH_SIZE = 1
N_CLASSES = 2
image = tf.cast(image_array, tf.float32)
image = tf.image.per_image_standardization(image)
image = tf.reshape(image, [1, 208, 208, 3])
logit = cnn_inference(image, BATCH_SIZE, N_CLASSES)
logit = tf.nn.softmax(logit)
x = tf.placeholder(tf.float32, shape=[208, 208, 3])
# you need to change the directories to yours.
logs_train_dir = 'E:/python ese/cat_dog/log/'
saver = tf.train.Saver()
with tf.Session() as sess:
print("Reading checkpoints...")
ckpt = tf.train.get_checkpoint_state(logs_train_dir)
if ckpt and ckpt.model_checkpoint_path:
global_step = ckpt.model_checkpoint_path.split('/')[-1].split('-')[-1]
saver.restore(sess, ckpt.model_checkpoint_path)
print('Loading success, global_step is %s' % global_step)
else:
print('No checkpoint file found')
prediction = sess.run(logit, feed_dict={x: image_array})
max_index = np.argmax(prediction)
#if max_index == 0:
print('有 %.6f可能性是猫' % prediction[:, 0])
# else:
print('有 %.6f可能性是狗' % prediction[:, 1])
plt.imshow(image_array)
plt.show()
if __name__ == '__main__':
start = time.clock()
train()
#evaluate_one_image()
elapsed = (time.clock() - start)
print("用时%f 小时:" %(elapsed/3600))