在 keras 中预训练的密集层之间添加 dropout 层 [英] Add dropout layers between pretrained dense layers in keras
本文介绍了在 keras 中预训练的密集层之间添加 dropout 层的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
在keras.applications中，有一个在imagenet上预训练的VGG16模型.
In keras.applications, there is a VGG16 model pre-trained on imagenet.
from keras.applications import VGG16
model = VGG16(weights='imagenet')
此模型具有以下结构.
Layer (type) Output Shape Param # Connected to
====================================================================================================
input_1 (InputLayer) (None, 3, 224, 224) 0
____________________________________________________________________________________________________
block1_conv1 (Convolution2D) (None, 64, 224, 224) 1792 input_1[0][0]
____________________________________________________________________________________________________
block1_conv2 (Convolution2D) (None, 64, 224, 224) 36928 block1_conv1[0][0]
____________________________________________________________________________________________________
block1_pool (MaxPooling2D) (None, 64, 112, 112) 0 block1_conv2[0][0]
____________________________________________________________________________________________________
block2_conv1 (Convolution2D) (None, 128, 112, 112) 73856 block1_pool[0][0]
____________________________________________________________________________________________________
block2_conv2 (Convolution2D) (None, 128, 112, 112) 147584 block2_conv1[0][0]
____________________________________________________________________________________________________
block2_pool (MaxPooling2D) (None, 128, 56, 56) 0 block2_conv2[0][0]
____________________________________________________________________________________________________
block3_conv1 (Convolution2D) (None, 256, 56, 56) 295168 block2_pool[0][0]
____________________________________________________________________________________________________
block3_conv2 (Convolution2D) (None, 256, 56, 56) 590080 block3_conv1[0][0]
____________________________________________________________________________________________________
block3_conv3 (Convolution2D) (None, 256, 56, 56) 590080 block3_conv2[0][0]
____________________________________________________________________________________________________
block3_pool (MaxPooling2D) (None, 256, 28, 28) 0 block3_conv3[0][0]
____________________________________________________________________________________________________
block4_conv1 (Convolution2D) (None, 512, 28, 28) 1180160 block3_pool[0][0]
____________________________________________________________________________________________________
block4_conv2 (Convolution2D) (None, 512, 28, 28) 2359808 block4_conv1[0][0]
____________________________________________________________________________________________________
block4_conv3 (Convolution2D) (None, 512, 28, 28) 2359808 block4_conv2[0][0]
____________________________________________________________________________________________________
block4_pool (MaxPooling2D) (None, 512, 14, 14) 0 block4_conv3[0][0]
____________________________________________________________________________________________________
block5_conv1 (Convolution2D) (None, 512, 14, 14) 2359808 block4_pool[0][0]
____________________________________________________________________________________________________
block5_conv2 (Convolution2D) (None, 512, 14, 14) 2359808 block5_conv1[0][0]
____________________________________________________________________________________________________
block5_conv3 (Convolution2D) (None, 512, 14, 14) 2359808 block5_conv2[0][0]
____________________________________________________________________________________________________
block5_pool (MaxPooling2D) (None, 512, 7, 7) 0 block5_conv3[0][0]
____________________________________________________________________________________________________
flatten (Flatten) (None, 25088) 0 block5_pool[0][0]
____________________________________________________________________________________________________
fc1 (Dense) (None, 4096) 102764544 flatten[0][0]
____________________________________________________________________________________________________
fc2 (Dense) (None, 4096) 16781312 fc1[0][0]
____________________________________________________________________________________________________
predictions (Dense) (None, 1000) 4097000 fc2[0][0]
====================================================================================================
Total params: 138,357,544
Trainable params: 138,357,544
Non-trainable params: 0
____________________________________________________________________________________________________
我想在密集层(fc1、fc2 和预测)之间使用 dropout 层微调这个模型，同时保持模型的所有预训练权重完好无损.我知道可以使用 model.layers 单独访问每个层，但我还没有找到如何在现有层之间添加新层的方法.
I would like to fine-tune this model with dropout layers between the dense layers (fc1, fc2 and predictions), while keeping all the pre-trained weights of the model intact. I know it's possible to access each layer individually with model.layers, but I haven't found anywhere how to add new layers between the existing layers.
这样做的最佳做法是什么?
What's the best practice of doing this?
推荐答案
我自己通过使用 Keras 函数式 API
from keras.applications import VGG16
from keras.layers import Dropout
from keras.models import Model
model = VGG16(weights='imagenet')
# Store the fully connected layers
fc1 = model.layers[-3]
fc2 = model.layers[-2]
predictions = model.layers[-1]
# Create the dropout layers
dropout1 = Dropout(0.85)
dropout2 = Dropout(0.85)
# Reconnect the layers
x = dropout1(fc1.output)
x = fc2(x)
x = dropout2(x)
predictors = predictions(x)
# Create a new model
model2 = Model(input=model.input, output=predictors)
model2 有我想要的 dropout 层
model2 has the dropout layers as I wanted
____________________________________________________________________________________________________
Layer (type) Output Shape Param # Connected to
====================================================================================================
input_1 (InputLayer) (None, 3, 224, 224) 0
____________________________________________________________________________________________________
block1_conv1 (Convolution2D) (None, 64, 224, 224) 1792 input_1[0][0]
____________________________________________________________________________________________________
block1_conv2 (Convolution2D) (None, 64, 224, 224) 36928 block1_conv1[0][0]
____________________________________________________________________________________________________
block1_pool (MaxPooling2D) (None, 64, 112, 112) 0 block1_conv2[0][0]
____________________________________________________________________________________________________
block2_conv1 (Convolution2D) (None, 128, 112, 112) 73856 block1_pool[0][0]
____________________________________________________________________________________________________
block2_conv2 (Convolution2D) (None, 128, 112, 112) 147584 block2_conv1[0][0]
____________________________________________________________________________________________________
block2_pool (MaxPooling2D) (None, 128, 56, 56) 0 block2_conv2[0][0]
____________________________________________________________________________________________________
block3_conv1 (Convolution2D) (None, 256, 56, 56) 295168 block2_pool[0][0]
____________________________________________________________________________________________________
block3_conv2 (Convolution2D) (None, 256, 56, 56) 590080 block3_conv1[0][0]
____________________________________________________________________________________________________
block3_conv3 (Convolution2D) (None, 256, 56, 56) 590080 block3_conv2[0][0]
____________________________________________________________________________________________________
block3_pool (MaxPooling2D) (None, 256, 28, 28) 0 block3_conv3[0][0]
____________________________________________________________________________________________________
block4_conv1 (Convolution2D) (None, 512, 28, 28) 1180160 block3_pool[0][0]
____________________________________________________________________________________________________
block4_conv2 (Convolution2D) (None, 512, 28, 28) 2359808 block4_conv1[0][0]
____________________________________________________________________________________________________
block4_conv3 (Convolution2D) (None, 512, 28, 28) 2359808 block4_conv2[0][0]
____________________________________________________________________________________________________
block4_pool (MaxPooling2D) (None, 512, 14, 14) 0 block4_conv3[0][0]
____________________________________________________________________________________________________
block5_conv1 (Convolution2D) (None, 512, 14, 14) 2359808 block4_pool[0][0]
____________________________________________________________________________________________________
block5_conv2 (Convolution2D) (None, 512, 14, 14) 2359808 block5_conv1[0][0]
____________________________________________________________________________________________________
block5_conv3 (Convolution2D) (None, 512, 14, 14) 2359808 block5_conv2[0][0]
____________________________________________________________________________________________________
block5_pool (MaxPooling2D) (None, 512, 7, 7) 0 block5_conv3[0][0]
____________________________________________________________________________________________________
flatten (Flatten) (None, 25088) 0 block5_pool[0][0]
____________________________________________________________________________________________________
fc1 (Dense) (None, 4096) 102764544 flatten[0][0]
____________________________________________________________________________________________________
dropout_1 (Dropout) (None, 4096) 0 fc1[0][0]
____________________________________________________________________________________________________
fc2 (Dense) (None, 4096) 16781312 dropout_1[0][0]
____________________________________________________________________________________________________
dropout_2 (Dropout) (None, 4096) 0 fc2[1][0]
____________________________________________________________________________________________________
predictions (Dense) (None, 1000) 4097000 dropout_2[0][0]
====================================================================================================
Total params: 138,357,544
Trainable params: 138,357,544
Non-trainable params: 0
____________________________________________________________________________________________________
这篇关于在 keras 中预训练的密集层之间添加 dropout 层的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
查看全文
