如何在此CNN优化代码中使用自己的数据

时间:2018-07-27 20:39:28

标签: python machine-learning conv-neural-network

我正在尝试微调inception-v3,以便它能够在存在信号和不存在信号的图像之间做出决定。如何编辑代码,以便可以对我的数据进行训练?这是微调inception-v3的代码:

from keras.applications.inception_v3 import InceptionV3
from keras.preprocessing import image
from keras.models import Model
from keras.layers import Dense, GlobalAveragePooling2D
from keras import backend as K

# create the base pre-trained model
base_model = InceptionV3(weights='imagenet', 
include_top=False)

# add a global spatial average pooling layer
x = base_model.output
x = GlobalAveragePooling2D()(x)
# let's add a fully-connected layer
x = Dense(1024, activation='relu')(x)
# and a logistic layer -- let's say we have 200 classes
predictions = Dense(200, activation='softmax')(x)

# this is the model we will train
model = Model(inputs=base_model.input, outputs=predictions)

# first: train only the top layers (which were randomly 
# initialized)
# i.e. freeze all convolutional InceptionV3 layers
for layer in base_model.layers:
    layer.trainable = False

# compile the model (should be done *after* setting layers 
# to non-trainable)
model.compile(optimizer='rmsprop',loss='categorical_
crossentropy')

# train the model on the new data for a few epochs
model.fit_generator(...)

# at this point, the top layers are well trained and we can 
# start fine-tuning
# convolutional layers from inception V3. We will freeze the 
# bottom N layers
# and train the remaining top layers.

# let's visualize layer names and layer indices to see how 
# many layers
# we should freeze:
for i, layer in enumerate(base_model.layers):
   print(i, layer.name)

# we chose to train the top 2 inception blocks, i.e. we will 
#freeze
# the first 249 layers and unfreeze the rest:
for layer in model.layers[:249]:
   layer.trainable = False
for layer in model.layers[249:]:
   layer.trainable = True

# we need to recompile the model for these modifications to 
# take effect
# we use SGD with a low learning rate
from keras.optimizers import SGD
model.compile(optimizer=SGD(lr=0.0001, momentum=0.9), 
loss='categorical_crossentropy')

# we train our model again (this time fine-tuning the top 2 
#inception blocks
# alongside the top Dense layers
model.fit_generator(...)

非常感谢您提供的帮助。

0 个答案:

没有答案