使用ImageDataGenerator时的Keras拆分训练测试集

from keras.preprocessing.image import ImageDataGenerator

datagen = ImageDataGenerator(validation_split=0.2)

train_generator = datagen.flow_from_directory(
    'train_data_directory',
    target_size=(image_width, image_height),
    batch_size=batch_size,
    subset='training'
)

validation_generator = datagen.flow_from_directory(
    'train_data_directory',
    target_size=(image_width, image_height),
    batch_size=batch_size,
    subset='validation'
)

model.fit_generator(
    train_generator,
    steps_per_epoch=train_generator.samples // batch_size,
    validation_data=validation_generator,
    validation_steps=validation_generator.samples // batch_size,
    epochs=num_epochs
)