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#!/usr/bin/env python
# -*- coding: utf-8 -*-
__author__ = 'Seven'
import random
import numpy as np
from sklearn.model_selection import train_test_split
from keras.preprocessing.image import ImageDataGenerator
from keras.models import Sequential
from keras.layers import Dense, Activation, Flatten, Dropout
from keras.layers import Conv2D, MaxPool2D
from keras.optimizers import SGD
from keras.utils import np_utils
from keras.models import load_model
from keras import backend as K
from face_dataset import load_dataset, resize_image, IMAGE_SIZE
import warnings
import os
os.environ['TF_CPP_MIN_LOG_LEVEL'] = '2'
warnings.filterwarnings('ignore')
class Dataset:
def __init__(self, path_name):
# 训练集
self.train_images = None
self.train_labels = None
# 验证集
# self.valid_images = None
# self.valid_labels = None
# 测试集
self.test_images = None
self.test_labels = None
# 数据加载路径
self.path_name = path_name
# 当前库采用的维度顺序
self.input_shape = None
def load(self, img_rows=IMAGE_SIZE, img_cols=IMAGE_SIZE, img_channels=3, nb_classes=2):
# 加载数据集至内存
images, labels = load_dataset(self.path_name)
train_images, test_images, train_labels, test_labels = train_test_split(images, labels, test_size=0.3,
random_state=random.randint(0, 10))
if K.image_data_format() == 'channels_first':
train_images = train_images.reshape(train_images.shape[0], img_channels, img_rows, img_cols)
test_images = test_images.reshape(test_images.shape[0], img_channels, img_rows, img_cols)
self.input_shape = (img_channels, img_rows, img_cols)
else:
train_images = train_images.reshape(train_images.shape[0], img_rows, img_cols, img_channels)
test_images = test_images.reshape(test_images.shape[0], img_rows, img_cols, img_channels)
self.input_shape = (img_rows, img_cols, img_channels)
# 输出训练集、测试集的数量
print(train_images.shape[0], 'train samples')
print(test_images.shape[0], 'test samples')
# 我们的模型使用categorical_crossentropy作为损失函数,因此需要根据类别数量nb_classes将
# 类别标签进行one-hot编码使其向量化,在这里我们的类别只有两种,经过转化后标签数据变为二维
train_labels = np_utils.to_categorical(train_labels, nb_classes)
test_labels = np_utils.to_categorical(test_labels, nb_classes)
# 像素数据浮点化以便归一化
train_images = train_images.astype('float32')
test_images = test_images.astype('float32')
# 将其归一化,图像的各像素值归一化到0~1区间
train_images /= 255.0
test_images /= 255.0
self.train_images = train_images
self.test_images = test_images
self.train_labels = train_labels
self.test_labels = test_labels
# CNN网络模型类
class Model:
def __init__(self):
self.model = None
# 建立模型
def build_model(self, dataset, nb_classes=2):
# 构建一个空的网络模型,它是一个线性堆叠模型,各神经网络层会被顺序添加,专业名称为序贯模型或线性堆叠模型
self.model = Sequential()
# 以下代码将顺序添加CNN网络需要的各层,一个add就是一个网络层
self.model.add(Conv2D(32, 3, 3, border_mode='same',
input_shape=dataset.input_shape)) # 1 2维卷积层
self.model.add(Activation('relu')) # 2 激活函数层
self.model.add(Conv2D(32, 3, 3)) # 3 2维卷积层
self.model.add(Activation('relu')) # 4 激活函数层
self.model.add(MaxPool2D(pool_size=(2, 2))) # 5 池化层
self.model.add(Dropout(0.25)) # 6 Dropout层
self.model.add(Conv2D(64, 3, 3, border_mode='same')) # 7 2维卷积层
self.model.add(Activation('relu')) # 8 激活函数层
self.model.add(Conv2D(64, 3, 3)) # 9 2维卷积层
self.model.add(Activation('relu')) # 10 激活函数层
self.model.add(MaxPool2D(pool_size=(2, 2))) # 11 池化层
self.model.add(Dropout(0.25)) # 12 Dropout层
self.model.add(Flatten()) # 13 Flatten层
self.model.add(Dense(512)) # 14 Dense层,又被称作全连接层
self.model.add(Activation('relu')) # 15 激活函数层
self.model.add(Dropout(0.5)) # 16 Dropout层
self.model.add(Dense(nb_classes)) # 17 Dense层
self.model.add(Activation('softmax')) # 18 分类层,输出最终结果
# 输出模型概况
self.model.summary()
# 训练模型
def train(self, dataset, batch_size=20, nb_epoch=100, data_augmentation=True):
sgd = SGD(lr=0.01, decay=1e-6,
momentum=0.9, nesterov=True) # 采用SGD+momentum的优化器进行训练,首先生成一个优化器对象
self.model.compile(loss='categorical_crossentropy',
optimizer=sgd,
metrics=['accuracy']) # 完成实际的模型配置工作
# 不使用数据提升,所谓的提升就是从我们提供的训练数据中利用旋转、翻转、加噪声等方法创造新的
# 训练数据,有意识的提升训练数据规模,增加模型训练量
if not data_augmentation:
self.model.fit(dataset.train_images,
dataset.train_labels,
batch_size=batch_size,
nb_epoch=nb_epoch,
validation_data=(dataset.test_images, dataset.test_labels),
shuffle=True)
# 使用实时数据提升
else:
# 定义数据生成器用于数据提升,其返回一个生成器对象datagen,datagen每被调用一
# 次其生成一组数据(顺序生成),节省内存,其实就是python的数据生成器
datagen = ImageDataGenerator(
featurewise_center=False, # 是否使输入数据去中心化(均值为0),
samplewise_center=False, # 是否使输入数据的每个样本均值为0
featurewise_std_normalization=False, # 是否数据标准化(输入数据除以数据集的标准差)
samplewise_std_normalization=False, # 是否将每个样本数据除以自身的标准差
zca_whitening=False, # 是否对输入数据施以ZCA白化
rotation_range=20, # 数据提升时图片随机转动的角度(范围为0~180)
width_shift_range=0.2, # 数据提升时图片水平偏移的幅度(单位为图片宽度的占比,0~1之间的浮点数)
height_shift_range=0.2, # 同上,只不过这里是垂直
horizontal_flip=True, # 是否进行随机水平翻转
vertical_flip=False) # 是否进行随机垂直翻转
# 计算整个训练样本集的数量以用于特征值归一化、ZCA白化等处理
datagen.fit(dataset.train_images)
# 利用生成器开始训练模型
self.model.fit_generator(datagen.flow(dataset.train_images, dataset.train_labels,
batch_size=batch_size),
samples_per_epoch=dataset.train_images.shape[0],
nb_epoch=nb_epoch,
validation_data=(dataset.test_images, dataset.test_labels))
MODEL_PATH = 'D:/model/model.h5'
def save_model(self, file_path=MODEL_PATH):
self.model.save(file_path)
def load_model(self, file_path=MODEL_PATH):
self.model = load_model(file_path)
def evaluate(self, dataset):
score = self.model.evaluate(dataset.test_images, dataset.test_labels, verbose=1)
# print("%s: %.2f%%" % (self.model.metrics_names[1], score[1] * 100))
print(f'{self.model.metrics_names[1]}:{score[1] * 100}%')
# 识别人脸
def face_predict(self, image):
# 依然是根据后端系统确定维度顺序
if K.image_dim_ordering() == 'th' and image.shape != (1, 3, IMAGE_SIZE, IMAGE_SIZE):
image = resize_image(image) # 尺寸必须与训练集一致都应该是IMAGE_SIZE x IMAGE_SIZE
image = image.reshape((1, 3, IMAGE_SIZE, IMAGE_SIZE)) # 与模型训练不同,这次只是针对1张图片进行预测
elif K.image_dim_ordering() == 'tf' and image.shape != (1, IMAGE_SIZE, IMAGE_SIZE, 3):
image = resize_image(image)
image = image.reshape((1, IMAGE_SIZE, IMAGE_SIZE, 3))
# 浮点并归一化
image = image.astype('float32')
image /= 255.0
# 给出输入属于各个类别的概率,我们是二值类别,则该函数会给出输入图像属于0和1的概率各为多少
result = self.model.predict_proba(image)
print('result:', result)
# 给出类别预测:0或者1
result = self.model.predict_classes(image)
# 返回类别预测结果
return result[0]
if __name__ == '__main__':
dataset = Dataset('D:/data')
dataset.load()
#训练模型
model = Model()
model.build_model(dataset)
#测试训练函数
model.train(dataset)
model.save_model(file_path='D:/model/model.h5')
#评估模型
#model = Model()
#model.load_model(file_path='D:/model/model.h5')
#model.evaluate(dataset)