使用GPU在AIStudio服务器进行猫狗分类 Keras框架

本地没有GPU环境，今天在百度AIStudio的GPU服务器上竟然跑起来了Keras版本的猫狗分类，服务器配置如图：

　　具体操作步骤。
　　1.首先打开百度AI Studio，并建立自己的工程。
　　2.数据准备，下载猫狗分类数据集在本地电脑，选取猫狗各2000图片压缩为zip文件，在刚建立的工程中上次zip文件到百度服务器（最大上传150M的文件）
　　3.服务器中解压zip文件，需要先安装zip,同时在notebook中添加图片分类脚本，将数据集分为训练集、验证集和测试集，脚本代码下边会附上。

pip install zip

4.安装训练所需要的库，keras和TensorFlow

pip install keras
pip install tensorflow

5.将模型代码添加到notebook并运行。

数据集分类脚本，将上边的zip文件解压到/home/aistudio/data/datasets

import os, shutil
origin_dataset_dir = ‘/home/aistudio/data/datasets‘
base_dir = ‘/home/aistudio/data/datasets_small‘
if not os.path.exists(base_dir):
    os.mkdir(base_dir)
train_dir = os.path.join(base_dir, ‘train‘)
os.mkdir(train_dir)
validation_dir = os.path.join(base_dir, ‘validation‘)
os.mkdir(validation_dir)
test_dir = os.path.join(base_dir, ‘test‘)
os.mkdir(test_dir)

train_cats_dir = os.path.join(train_dir, ‘cats‘)
os.mkdir(train_cats_dir)
train_dogs_dir = os.path.join(train_dir, ‘dogs‘)
os.mkdir(train_dogs_dir)

validation_cats_dir = os.path.join(validation_dir, ‘cats‘)
os.mkdir(validation_cats_dir)
validation_dogs_dir = os.path.join(validation_dir, ‘dogs‘)
os.mkdir(validation_dogs_dir)

test_cats_dir = os.path.join(test_dir, ‘cats‘)
os.mkdir(test_cats_dir)
test_dogs_dir = os.path.join(test_dir, ‘dogs‘)
os.mkdir(test_dogs_dir)

fnames = [‘cat.{}.jpg‘.format(i) for i in range(1000)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(train_cats_dir, fname)
    shutil.copyfile(src, dst)
fnames = [‘cat.{}.jpg‘.format(i) for i in range(1000, 1500)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(validation_cats_dir, fname)
    shutil.copyfile(src, dst)
fnames = [‘cat.{}.jpg‘.format(i) for i in range(1500, 2000)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(test_cats_dir, fname)
    shutil.copyfile(src, dst)

fnames = [‘dog.{}.jpg‘.format(i) for i in range(1000)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(train_dogs_dir, fname)
    shutil.copyfile(src, dst)
fnames = [‘dog.{}.jpg‘.format(i) for i in range(1000, 1500)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(validation_dogs_dir, fname)
    shutil.copyfile(src, dst)
fnames = [‘dog.{}.jpg‘.format(i) for i in range(1500, 2000)]
for fname in fnames:
    src = os.path.join(origin_dataset_dir, fname)
    dst = os.path.join(test_dogs_dir, fname)
    shutil.copyfile(src, dst)
print(‘total traing cat images:‘, len(os.listdir(train_cats_dir)))
print(‘total traing dog images:‘, len(os.listdir(train_dogs_dir)))
print(‘total validation cat images:‘, len(os.listdir(validation_cats_dir)))
print(‘total validation dog images:‘, len(os.listdir(validation_dogs_dir)))
print(‘total test cat images:‘, len(os.listdir(test_cats_dir)))
print(‘total test dog images:‘, len(os.listdir(test_dogs_dir)))

模型代码如下，由于数据集较小，进行了数据增强，同时采用dropout正则化来规避过拟合：

from keras import models
from keras import layers
from keras import optimizers
from keras.preprocessing.image import ImageDataGenerator
import matplotlib.pyplot as plt

model = models.Sequential()
model.add(layers.Conv2D(32, (3, 3), activation=‘relu‘,
                        input_shape=(150, 150, 3)))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Conv2D(64, (3, 3), activation=‘relu‘))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Conv2D(128, (3, 3), activation=‘relu‘))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Conv2D(128, (3, 3), activation=‘relu‘))
model.add(layers.MaxPooling2D((2, 2)))
model.add(layers.Flatten())
model.add(layers.Dropout(0.5))
model.add(layers.Dense(512, activation=‘relu‘))
model.add(layers.Dense(1, activation=‘sigmoid‘))
print(‘--------------------------------------------------------------‘, model.summary())
model.compile(loss=‘binary_crossentropy‘,
              optimizer=optimizers.RMSprop(lr=1e-4),
              metrics=[‘acc‘])

train_dir = ‘/home/aistudio/data/datasets_small/train‘
validation_dir = ‘/home/aistudio/data/datasets_small/validation‘
train_datagen = ImageDataGenerator(
    rescale=1./255,
    rotation_range=40,
    width_shift_range=0.2,
    height_shift_range=0.2,
    shear_range=0.2,
    zoom_range=0.2,
    horizontal_flip=True,)
test_datagen = ImageDataGenerator(rescale=1./255)

train_generator = train_datagen.flow_from_directory(
    train_dir,
    target_size=(150, 150),
    batch_size=32,
    class_mode=‘binary‘)
validation_generator = test_datagen.flow_from_directory(
    validation_dir,
    target_size=(150, 150),
    batch_size=32,
    class_mode=‘binary‘)

history = model.fit_generator(
        train_generator,
        steps_per_epoch=100,
        epochs=100,
        validation_data=validation_generator,
        validation_steps=50
    )
model.save(‘cat_and_dog_small_2.h5‘)


acc = history.history[‘acc‘]
val_acc = history.history[‘val_acc‘]
loss = history.history[‘loss‘]
val_loss = history.history[‘val_loss‘]

epochs = range(1, len(acc)+1)
plt.plot(epochs, acc, ‘bo‘, label=‘Traing acc‘)
plt.plot(epochs, val_acc, ‘b‘, label=‘Validation acc‘)
plt.title(‘Training and validation accuracy‘)
plt.legend()
plt.figure()

plt.plot(epochs, loss, ‘bo‘, label=‘Traing loss‘)
plt.plot(epochs, val_loss, ‘b‘, label=‘Validation loss‘)
plt.title(‘Training and validation loss‘)
plt.legend()
plt.show()

运行起来后可以看到每轮耗时大概36秒，本地CPU每轮大概耗时100秒。真是工欲善其事必先利其器。这里声明一点，不是paddlepaddle做的不好，是我刚开始接触深度学习，首先看的框架就是keras，所以一些验证学习都是基于keras上来做的，后边肯定会转向paddlepaddl，时间问题而已。另外百度在深度学习的推广以及支持力度是真的给力，这里深深的感谢。

百度GPU上：

 本地CPU：

训练结束的精度和损失图示如下，精度80%左右，验证损失变化较大，还需要进一步查看原因：