例子描述:
通过用CNN网络对 梵高,莫奈,毕加索,达芬奇 四位画家的作品进行学习,学出一个模型,这个模型具有识别这个四位画家作品的能力。
所需环境:Python3.6 + Tensorflow
如果使用cpu版本,可以参考:https://www.jianshu.com/p/da141c730180
如果使用gpu版本,可以参考:https://www.jianshu.com/p/62d414aa843e
3个步骤:
- 使用爬虫爬去百度图片
- 搭建神经网络,训练,产生模型
- 使用产生的模型,识别与分类
1. 使用爬虫爬去百度图片
通过chrome开发者工具分析,我们得到一个百度图片的api接口,通过接口的数据可以拿到百度图片的地址,如图:
用过分析,这个url地址的主要的三个参数是:
- pn: 当前页的图片数量偏移量,如 60 表示当前页是第二页,图片数的偏移是60
- rn: 每页返回多少图片,如 30 表示每页三十张图片
- queryWordh和word:搜索关键字,如 :梵高作品
我们只要调整这些参数,就可以获取任意的百度图片和图片数量,然后通过python代码爬去图片保存到本地磁盘目录。
新建文件:spider.py
代码如下:
import requests
import os
import urllib
import json
#定义下载图片的函数
def downImg(imgUrl, dirPath, imgName):
filename = os.path.join(dirPath, imgName)
try:
#加Referer头,防止百度拒绝你的请求
myheaders = {
'Referer':'https://image.baidu.com'
}
res = requests.get(imgUrl, timeout=15,headers=myheaders)
if str(res.status_code)[0] == "4":
print(str(res.status_code), ":", imgUrl)
return False
except Exception as e:
print("抛出异常:", imgUrl)
print(e)
return False
with open(filename, "wb") as f:
f.write(res.content)
return True
words = [["梵高作品",'FG'],['莫奈作品','MN'],['毕加索作品','BJS'],['达芬奇作品','DFQ']] #搜索关键字,如 :梵高作品
trainPath = "train_data/"
#如果文件夹不存在,创建文件夹
if not os.path.exists(trainPath):
os.mkdir(trainPath)
for word in words:
dirPath = trainPath + word[1]
# 如果文件夹不存在,创建文件夹
if not os.path.exists(dirPath):
os.mkdir(dirPath)
word = urllib.parse.quote(word[0]) #因为是中文,所以要进行urlencode转换
pn = 30 #当前页的图片数量偏移量,如 60 表示当前页是第二页,图片数的偏移是60
rn = 30 #每每页返回多少图片,如 30 表示每页三十张图片
i = 1 #图片编号
while pn <= 30 * 20: #获取20页的图片,总共600张,建议修改页数,爬去更多一点的图片
try:
url = 'https://image.baidu.com/search/acjson?tn=resultjson_com&ipn=rj&ct=201326592&is=&fp=result&queryWord=' + word + '&cl=2&lm=-1&ie=utf-8&oe=utf-8&adpicid=&st=-1&z=&ic=&hd=&latest=©right=&word=' + word + '=&se=&tab=&width=&height=&face=0&istype=2&qc=&nc=1&fr=&expermode=&force=&pn=' + str(
pn) + '&rn=' + str(rn) + '&gsm=3c&1550715038298='
jsonBytes = requests.get(url, timeout=10).content # 获取json数据-字节
jsonData = jsonBytes.decode('utf-8') # json数据-字节转字符串
print("---------------------------------------------------------")
jsonData = jsonData.replace("\\'", '') #不加这个字符串替换json.loads时会报错,意思是去掉字符串中的\'
print(jsonData)
print("---------------------------------------------------------")
jsonObj = json.loads(jsonData) # json数据-字符串转对象
if 'data' in jsonObj:
for item in jsonObj['data']:
if 'thumbURL' in item:
imgName = str(i) + ".jpg"
downImg(item['thumbURL'], dirPath, imgName) # 下载图片
print(item['thumbURL'])
i += 1
pn += rn # 下一页
except Exception as e:
print(e)
代码执行完成后,在当前目录下,我们就得到了后面训练用的样本数据,目录文件如下:
到此,样本数据就准备好了,下面我们要搭建神经网络了。
2. 搭建神经网络,读取图片,训练,产生模型
这里要用到opencv,所以要安装opencv模块
# 安装
pip install http://ai-download.xmgc360.com/opencv_python-3.3.0.10-cp36-cp36m-win_amd64.whl
还需安装 sklearn 模块
pip install sklearn -i https://pypi.tuna.tsinghua.edu.cn/simple
新建文件 dataset.py ,用于读取图片并预处理,代码如下:
import cv2
import os
import glob
from sklearn.utils import shuffle
import numpy as np
def load_train(train_path, image_size, classes):
images = []
labels = []
img_names = []
cls = []
print('Going to read training images')
for fields in classes:
index = classes.index(fields)
print('Now going to read {} files (Index: {})'.format(fields, index))
path = os.path.join(train_path, fields, '*g')
files = glob.glob(path)
for fl in files:
try:
#读取图片
image = cv2.imread(fl)
#等比例压缩到64*64
image = cv2.resize(image, (image_size, image_size), 0, 0, cv2.INTER_LINEAR)
#转为浮点型
image = image.astype(np.float32)
#归一化处理
image = np.multiply(image, 1.0 / 255.0)
images.append(image)
label = np.zeros(len(classes))
label[index] = 1.0
labels.append(label)
flbase = os.path.basename(fl)
img_names.append(flbase)
cls.append(fields)
except Exception as e:
print(e)
images = np.array(images)
labels = np.array(labels)
img_names = np.array(img_names)
cls = np.array(cls)
return images, labels, img_names, cls
class DataSet(object):
def __init__(self, images, labels, img_names, cls):
self._num_examples = images.shape[0]
self._images = images
self._labels = labels
self._img_names = img_names
self._cls = cls
self._epochs_done = 0
self._index_in_epoch = 0
@property
def images(self):
return self._images
@property
def labels(self):
return self._labels
@property
def img_names(self):
return self._img_names
@property
def cls(self):
return self._cls
@property
def num_examples(self):
return self._num_examples
@property
def epochs_done(self):
return self._epochs_done
def next_batch(self, batch_size):
"""Return the next `batch_size` examples from this data set."""
start = self._index_in_epoch
self._index_in_epoch += batch_size
if self._index_in_epoch > self._num_examples:
# After each epoch we update this
self._epochs_done += 1
start = 0
self._index_in_epoch = batch_size
assert batch_size <= self._num_examples
end = self._index_in_epoch
return self._images[start:end], self._labels[start:end], self._img_names[start:end], self._cls[start:end]
def read_train_sets(train_path, image_size, classes, validation_size):
class DataSets(object):
pass
data_sets = DataSets()
images, labels, img_names, cls = load_train(train_path, image_size, classes)
images, labels, img_names, cls = shuffle(images, labels, img_names, cls)
if isinstance(validation_size, float):
validation_size = int(validation_size * images.shape[0])
validation_images = images[:validation_size]
validation_labels = labels[:validation_size]
validation_img_names = img_names[:validation_size]
validation_cls = cls[:validation_size]
train_images = images[validation_size:]
train_labels = labels[validation_size:]
train_img_names = img_names[validation_size:]
train_cls = cls[validation_size:]
data_sets.train = DataSet(train_images, train_labels, train_img_names, train_cls)
data_sets.valid = DataSet(validation_images, validation_labels, validation_img_names, validation_cls)
return data_sets
新建 train.py 文件,搭建神经网络,训练,产生模型,代码如下:
import dataset
import tensorflow as tf
import time
from datetime import timedelta
import math
import random
import numpy as np
# conda install --channel https://conda.anaconda.org/menpo opencv3
#Adding Seed so that random initialization is consistent
from numpy.random import seed
seed(10)
from tensorflow import set_random_seed
set_random_seed(20)
batch_size = 32
#Prepare input data
classes = ['BJS','DFQ','FG','MN']
num_classes = len(classes)
# 20% of the data will automatically be used for validation
validation_size = 0.2
img_size = 64
num_channels = 3
train_path='train_data'
# We shall load all the training and validation images and labels into memory using openCV and use that during training
data = dataset.read_train_sets(train_path, img_size, classes, validation_size=validation_size)
print("Complete reading input data. Will Now print a snippet of it")
print("Number of files in Training-set:\t\t{}".format(len(data.train.labels)))
print("Number of files in Validation-set:\t{}".format(len(data.valid.labels)))
session = tf.Session()
x = tf.placeholder(tf.float32, shape=[None, img_size,img_size,num_channels], name='x')
## labels
y_true = tf.placeholder(tf.float32, shape=[None, num_classes], name='y_true')
y_true_cls = tf.argmax(y_true, dimension=1)
##Network graph params
filter_size_conv1 = 3
num_filters_conv1 = 32
filter_size_conv2 = 3
num_filters_conv2 = 32
filter_size_conv3 = 3
num_filters_conv3 = 64
fc_layer_size = 1024
def create_weights(shape):
return tf.Variable(tf.truncated_normal(shape, stddev=0.05))
def create_biases(size):
return tf.Variable(tf.constant(0.05, shape=[size]))
def create_convolutional_layer(input,
num_input_channels,
conv_filter_size,
num_filters):
## We shall define the weights that will be trained using create_weights function. 3 3 3 32
weights = create_weights(shape=[conv_filter_size, conv_filter_size, num_input_channels, num_filters])
## We create biases using the create_biases function. These are also trained.
biases = create_biases(num_filters)
## Creating the convolutional layer
layer = tf.nn.conv2d(input=input,
filter=weights,
strides=[1, 1, 1, 1],
padding='SAME')
layer += biases
layer = tf.nn.relu(layer)
## We shall be using max-pooling.
layer = tf.nn.max_pool(value=layer,
ksize=[1, 2, 2, 1],
strides=[1, 2, 2, 1],
padding='SAME')
## Output of pooling is fed to Relu which is the activation function for us.
#layer = tf.nn.relu(layer)
return layer
def create_flatten_layer(layer):
#We know that the shape of the layer will be [batch_size img_size img_size num_channels]
# But let's get it from the previous layer.
layer_shape = layer.get_shape()
## Number of features will be img_height * img_width* num_channels. But we shall calculate it in place of hard-coding it.
num_features = layer_shape[1:4].num_elements()
## Now, we Flatten the layer so we shall have to reshape to num_features
layer = tf.reshape(layer, [-1, num_features])
return layer
def create_fc_layer(input,
num_inputs,
num_outputs,
use_relu=True):
#Let's define trainable weights and biases.
weights = create_weights(shape=[num_inputs, num_outputs])
biases = create_biases(num_outputs)
# Fully connected layer takes input x and produces wx+b.Since, these are matrices, we use matmul function in Tensorflow
layer = tf.matmul(input, weights) + biases
layer=tf.nn.dropout(layer,keep_prob=0.7)
if use_relu:
layer = tf.nn.relu(layer)
return layer
#卷积层1(包括卷积,池化,激活)
layer_conv1 = create_convolutional_layer(input=x,
num_input_channels=num_channels,
conv_filter_size=filter_size_conv1,
num_filters=num_filters_conv1)
#卷积层2(包括卷积,池化,激活)
layer_conv2 = create_convolutional_layer(input=layer_conv1,
num_input_channels=num_filters_conv1,
conv_filter_size=filter_size_conv2,
num_filters=num_filters_conv2)
#卷积层3(包括卷积,池化,激活)
layer_conv3= create_convolutional_layer(input=layer_conv2,
num_input_channels=num_filters_conv2,
conv_filter_size=filter_size_conv3,
num_filters=num_filters_conv3)
#把上面三个卷积层处理后的结果转化为一维向量,才能提供给全连层
layer_flat = create_flatten_layer(layer_conv3)
#全连接层1
layer_fc1 = create_fc_layer(input=layer_flat,
num_inputs=layer_flat.get_shape()[1:4].num_elements(),
num_outputs=fc_layer_size,
use_relu=True)
#全连接层2
layer_fc2 = create_fc_layer(input=layer_fc1,
num_inputs=fc_layer_size,
num_outputs=num_classes,
use_relu=False)
y_pred = tf.nn.softmax(layer_fc2,name='y_pred')
y_pred_cls = tf.argmax(y_pred, dimension=1)
session.run(tf.global_variables_initializer())
cross_entropy = tf.nn.softmax_cross_entropy_with_logits(logits=layer_fc2,
labels=y_true)
cost = tf.reduce_mean(cross_entropy)
optimizer = tf.train.AdamOptimizer(learning_rate=1e-4).minimize(cost)
correct_prediction = tf.equal(y_pred_cls, y_true_cls)
accuracy = tf.reduce_mean(tf.cast(correct_prediction, tf.float32))
session.run(tf.global_variables_initializer())
def show_progress(epoch, feed_dict_train, feed_dict_validate, val_loss,i):
acc = session.run(accuracy, feed_dict=feed_dict_train)
val_acc = session.run(accuracy, feed_dict=feed_dict_validate)
msg = "Training Epoch {0}--- iterations: {1}--- Training Accuracy: {2:>6.1%}, Validation Accuracy: {3:>6.1%}, Validation Loss: {4:.3f}"
print(msg.format(epoch + 1,i, acc, val_acc, val_loss))
total_iterations = 0
saver = tf.train.Saver()
def train(num_iteration):
global total_iterations
for i in range(total_iterations,
total_iterations + num_iteration):
x_batch, y_true_batch, _, cls_batch = data.train.next_batch(batch_size)
x_valid_batch, y_valid_batch, _, valid_cls_batch = data.valid.next_batch(batch_size)
feed_dict_tr = {x: x_batch,
y_true: y_true_batch}
feed_dict_val = {x: x_valid_batch,
y_true: y_valid_batch}
session.run(optimizer, feed_dict=feed_dict_tr)
if i % int(data.train.num_examples/batch_size) == 0:
val_loss = session.run(cost, feed_dict=feed_dict_val)
epoch = int(i / int(data.train.num_examples/batch_size))
show_progress(epoch, feed_dict_tr, feed_dict_val, val_loss,i)
saver.save(session, './model/painting.ckpt',global_step=i)
total_iterations += num_iteration
train(num_iteration=8000)
运行 train.py 进行训练 , 如图:
训练中结果截图:
等训练完成后,会传输模型文件,如图:
产生模型以后,我们使用最新的模型文件来预测,这里我们使用:
painting.ckpt-7998.meta 存储的是神经网络结构
painting.ckpt-7998.data 模型数据本身
然后在下面的代码里引用
3. 识别与分类
新建文件:predict.py,代码中加载模型,制定预测的文件名 fg_test_1.jpg。
代码如下:
import tensorflow as tf
import numpy as np
import os,glob,cv2
import sys,argparse
image_size=64
num_channels=3
images = []
path = 'fg_test_1.jpg'
image = cv2.imread(path)
# Resizing the image to our desired size and preprocessing will be done exactly as done during training
image = cv2.resize(image, (image_size, image_size),0,0, cv2.INTER_LINEAR)
images.append(image)
images = np.array(images, dtype=np.uint8)
images = images.astype('float32')
images = np.multiply(images, 1.0/255.0)
#The input to the network is of shape [None image_size image_size num_channels]. Hence we reshape.
x_batch = images.reshape(1, image_size,image_size,num_channels)
## Let us restore the saved model
sess = tf.Session()
# Step-1: Recreate the network graph. At this step only graph is created.
saver = tf.train.import_meta_graph('./model/painting.ckpt-7998.meta')
# Step-2: Now let's load the weights saved using the restore method.
saver.restore(sess, './model/painting.ckpt-7998')
# Accessing the default graph which we have restored
graph = tf.get_default_graph()
# Now, let's get hold of the op that we can be processed to get the output.
# In the original network y_pred is the tensor that is the prediction of the network
y_pred = graph.get_tensor_by_name("y_pred:0")
## Let's feed the images to the input placeholders
x= graph.get_tensor_by_name("x:0")
y_true = graph.get_tensor_by_name("y_true:0")
y_test_images = np.zeros((1, 4))
### Creating the feed_dict that is required to be fed to calculate y_pred
feed_dict_testing = {x: x_batch, y_true: y_test_images}
result=sess.run(y_pred, feed_dict=feed_dict_testing)
# result is of this format [probabiliy_of_rose probability_of_sunflower]
# dog [1 0]
res_label = ['BJS','DFQ','FG','MN']
print(res_label[result.argmax()])
预测文件:fg_test_1.jpg,放到当前目录下
预测结果如图:
结果是:FG,表示识别成功。
备注:
目录结构如下图:
附带窗口图形化预测代码:
所需安装模块:
pip install pillow -i https://pypi.tuna.tsinghua.edu.cn/simple
新建文件:prodict_gui.py,拷贝下面代码:
from tkinter import *
from tkinter import filedialog
from PIL import Image, ImageTk
import tensorflow as tf
import numpy as np
import cv2
import tkinter
import tkinter.messagebox
image_size=64
num_channels=3
images = []
filepath = ''
## 启动session
sess = tf.Session()
# 在家模型图结构
saver = tf.train.import_meta_graph('./model/painting.ckpt-145.meta')
# 加载模型权重
saver.restore(sess, './model/painting.ckpt-145')
# 获取图结构
graph = tf.get_default_graph()
if __name__ == "__main__":
root = Tk()
root.title('图形预测窗口')
#setting up a tkinter canvas with scrollbars
frame = Frame(root, bd=2, relief=SUNKEN)
frame.grid_rowconfigure(0, weight=1)
frame.grid_columnconfigure(0, weight=1)
xscroll = Scrollbar(frame, orient=HORIZONTAL)
xscroll.grid(row=1, column=0, sticky=E+W)
yscroll = Scrollbar(frame)
yscroll.grid(row=0, column=1, sticky=N+S)
canvas = Canvas(frame, bd=0, xscrollcommand=xscroll.set, yscrollcommand=yscroll.set)
canvas.grid(row=0, column=0, sticky=N+S+E+W)
xscroll.config(command=canvas.xview)
yscroll.config(command=canvas.yview)
frame.pack(fill=BOTH,expand=1)
def printcoords():
global filepath
File = filedialog.askopenfilename(parent=root, initialdir="D:/",title='Choose an image.')
filename = ImageTk.PhotoImage(Image.open(File))
canvas.image = filename
canvas.create_image(0,0,anchor='nw',image=filename)
filepath = File
def predict():
image_size = 64
num_channels = 3
images = []
path = filepath
print(path)
#image = cv2.imread(path) #不支持中文路径
image = cv2.imdecode(np.fromfile(path,dtype=np.uint8),-1) #支持中文路径
image = cv2.resize(image, (image_size, image_size), 0, 0, cv2.INTER_LINEAR)
images.append(image)
images = np.array(images, dtype=np.uint8)
images = images.astype('float32')
images = np.multiply(images, 1.0 / 255.0)
x_batch = images.reshape(1, image_size, image_size, num_channels)
# 获取tensor : y_pred
y_pred = graph.get_tensor_by_name("y_pred:0")
# 获取tensor : x
x = graph.get_tensor_by_name("x:0")
# 获取tensor : y_true
y_true = graph.get_tensor_by_name("y_true:0")
y_test_images = np.zeros((1, 4))
feed_dict_testing = {x: x_batch, y_true: y_test_images}
#run测试数据
result = sess.run(y_pred, feed_dict=feed_dict_testing)
res_label = ['这幅画作者毕加索','这幅画作者达芬奇', '这幅画作者梵高', '这幅画作者莫奈']
tkinter.messagebox.showinfo("图形预测结果",res_label[result.argmax()])
Button(root, text='2、图形预测', command=predict).pack(side=RIGHT)
Button(root,text='1、选择图片',command=printcoords).pack(side=RIGHT)
label = Label(root, text='请依次点击按钮>>>>>>')
label.pack(side=RIGHT)
root.mainloop()
界面截图: