Kaggle-VGG16
一、导包准备:
from keras import models
from keras.layers import Conv2D, MaxPooling2D, Dense, BatchNormalization, GlobalAveragePooling2D, Dropout
import numpy as np
import cv2
from sklearn.model_selection import train_test_split
import matplotlib.pyplot as plt
二、加载数据:
n = 25000
width = 128
x = np.zeros(shape=(n, width, width, 3), dtype=np.uint8)
y = np.zeros(shape=(n, 1), dtype=np.uint8)
for i in range(12500):
'''
image = cv2.imread('E:/09-KAGGLE/dogs-vs-cats-redux-kernels-edition/train/train/cat.%d.jpg' % i)
try:
if image is None:
print('error: train/cat.%d.jpg' % i)
break;
except AttributeError:
pass
'''
x[i] = cv2.resize(cv2.imread('E:/09-KAGGLE/dogs-vs-cats-redux-kernels-edition/train/train/cat.%d.jpg' % i), dsize=(width, width))
x[i+12500] = cv2.resize(cv2.imread('E:/09-KAGGLE/dogs-vs-cats-redux-kernels-edition/train/train/dog.%d.jpg' % i), dsize=(width, width))
y[12500:] = 1
原来相对路径读取文件的时候不定时报错:
error: (-215:Assertion failed) !ssize.empty() in function 'cv::resize’
原因:图像损坏无法读取,重新解压文件。
文件地址:https://pan.baidu.com/s/1H-aPZ5fOJT21lh7aIK4X4g
(网盘深度学习文件夹下dogs-vs-cats-redux-kernels-edition压缩包)
解决办法参考:添加链接描述
三、训练集与测试集拆分:
x_train, x_test, y_train, y_test = train_test_split(x, y, test_size=0.2)
四、搭建模型:
model = models.Sequential()
model.add(Conv2D(filters=32,kernel_size=(3,3), activation='relu', input_shape=(128,128,3), padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=32,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(Conv2D(filters=64,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=64,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(Conv2D(filters=128,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=128,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=128,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(Conv2D(filters=256,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=256,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=256,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(Conv2D(filters=512,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=512,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(Conv2D(filters=512,kernel_size=(3,3), activation='relu', padding='same'))
model.add(BatchNormalization())
model.add(MaxPooling2D(pool_size=(2,2)))
model.add(GlobalAveragePooling2D())
model.add(Dropout(0.5))
model.add(Dense(units=1, activation='sigmoid'))
这模型搭了我一晚上!每一层卷积的时候,如果不设定padding操作‘same’,图像会越来越小,后面的会报错:
Negative dimension size caused by subtracting 3 from 2 for ‘Conv2D’。
一层一层的summary后发现卷积到其中某一层时特征图大小只有2×2大小,卷积核大小是3×3,所以会有什么3 from 2的错误。
Conv2D层声明padding = 'same’就解决了。
五、模型编译:
model.compile(optimizer = 'adam', loss='binary_crossentropy', metrics=['accuracy'])
为什么要编译模型?
《Python深度学习》(弗朗索瓦·肖莱著 张亮译 人民邮电出版社)Page22:
六、模型训练:
h = model.fit(x_train,y_train, batch_size=128, epochs=50, validation_data=(x_test, y_test))
七、训练结果可视化:
plt.figure(figsize=(10,4))
plt.subplot(1, 2, 1)
plt.plot(h.history['loss'])
plt.plot(h.history['val_loss'])
plt.legend(['loss', 'val_loss'])
plt.ylabel('loss')
plt.xlabel('epoch')
print(h.history)
plt.subplot(1, 2, 2)
plt.plot(h.history['accuracy'])
plt.plot(h.history['val_accuracy'])
plt.legend(['acc', 'val_cc'])
plt.ylabel('acc')
plt.xlabel('epoch')
八、保存模型:
model.save('cats_and_dogs_small_2.h5')
九、model.summary
model.summary()
Model: “sequential_1”
Layer (type) Output Shape Param #
conv2d_1 (Conv2D) (None, 128, 128, 32) 896
batch_normalization_1 (Batch (None, 128, 128, 32) 128
conv2d_2 (Conv2D) (None, 128, 128, 32) 9248
batch_normalization_2 (Batch (None, 128, 128, 32) 128
max_pooling2d_1 (MaxPooling2 (None, 64, 64, 32) 0
conv2d_3 (Conv2D) (None, 64, 64, 64) 18496
batch_normalization_3 (Batch (None, 64, 64, 64) 256
conv2d_4 (Conv2D) (None, 64, 64, 64) 36928
batch_normalization_4 (Batch (None, 64, 64, 64) 256
max_pooling2d_2 (MaxPooling2 (None, 32, 32, 64) 0
conv2d_5 (Conv2D) (None, 32, 32, 128) 73856
batch_normalization_5 (Batch (None, 32, 32, 128) 512
conv2d_6 (Conv2D) (None, 32, 32, 128) 147584
batch_normalization_6 (Batch (None, 32, 32, 128) 512
conv2d_7 (Conv2D) (None, 32, 32, 128) 147584
batch_normalization_7 (Batch (None, 32, 32, 128) 512
max_pooling2d_3 (MaxPooling2 (None, 16, 16, 128) 0
conv2d_8 (Conv2D) (None, 16, 16, 256) 295168
batch_normalization_8 (Batch (None, 16, 16, 256) 1024
conv2d_9 (Conv2D) (None, 16, 16, 256) 590080
batch_normalization_9 (Batch (None, 16, 16, 256) 1024
conv2d_10 (Conv2D) (None, 16, 16, 256) 590080
batch_normalization_10 (Batc (None, 16, 16, 256) 1024
max_pooling2d_4 (MaxPooling2 (None, 8, 8, 256) 0
conv2d_11 (Conv2D) (None, 8, 8, 512) 1180160
batch_normalization_11 (Batc (None, 8, 8, 512) 2048
conv2d_12 (Conv2D) (None, 8, 8, 512) 2359808
batch_normalization_12 (Batc (None, 8, 8, 512) 2048
conv2d_13 (Conv2D) (None, 8, 8, 512) 2359808
batch_normalization_13 (Batc (None, 8, 8, 512) 2048
max_pooling2d_5 (MaxPooling2 (None, 4, 4, 512) 0
global_average_pooling2d_1 ( (None, 512) 0
dropout_1 (Dropout) (None, 512) 0
dense_1 (Dense) (None, 1) 513
Total params: 7,821,729
Trainable params: 7,815,969
Non-trainable params: 5,760
十、plot_model
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