微调网络,通常我们有一个初始化的模型参数文件,这里是不同于training from scratch,scrachtch指的是我们训练一个新的网络,在训练过程中,这些参数都被随机初始化,而fine-tuning,是我们可以在ImageNet上1000类分类训练好的参数的基础上,根据我们的分类识别任务进行特定的微调
这里我以一个车的识别为例,假设我们有1种车需要识别,我的任务对象是车,现在有ImageNet的模型参数文件,在这里使用的网络模型是CaffeNet,是一个小型的网络,其实别的网络如GoogleNet也是一样的原理。那么这个任务的变化可以表示为:
任务:分类 类别数目:1000(ImageNet上1000类的分类任务)------> 1(自己的特定数据集的分类任务车)
那么在网络的微调中,我们的整个流程分为以下几步:
1. 依然是准备好我们的训练数据和测试数据
2. 计算数据集的均值文件,因为集中特定领域的图像均值文件会跟ImageNet上比较General的数据的均值不太一样
3. 修改网络最后一层的输出类别,并且需要加快最后一层的参数学习速率
4. 调整Solver的配置参数,通常学习速率和步长,迭代次数都要适当减少
5. 启动训练,并且需要加载pretrained模型的参数
1.准备数据集
这一点就不用说了,准备两个txt文件,放成list的形式,可以参考caffe下的example,图像路径之后一个空格之后跟着类别的ID,如下,这里记住ID必须从0开始,要连续,否则会出错,loss不下降,按照要求写就OK。
这个是训练的图像label,测试的也同理
1. 创建lmdb文件,使用caffe下的convert_imageset 工具,具体命令如下:
./build/tools/convert_imageset /media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/ data/cartest/carlist.txt data/cartest/train_car_lmdb -resize_width=227 -resize_height=227 -check_size -shuffle true
其中第一个参数是基地址路径用来拼接的,第二个是label的文件,第三个是生成的数据库文件支持leveldb或者lmdb,接着是resize的大小,最后是否随机图片顺序
计算均值,使用caffe下的convert_imageset 工具,具体命令
./build/tools/compute_image_mean /media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/train_car_lmdb/ data/carmean.binaryproto
第一个参数是基地址路径用来拼接的,第二个是lmdb文件,第三个是生成的均值文件carmean.binaryproto
3.调整网络层参数
参照Caffe上的例程,我用的是CaffeNet,首先在输入层data层,修改我们的source 和 meanfile, 根据之前生成的lmdb 和mean.binaryproto修改即可。
最后输出层是fc8,
1.首先修改名字,这样预训练模型赋值的时候这里就会因为名字不匹配从而重新训练,也就达成了我们适应新任务的目的。
2.调整学习速率,因为最后一层是重新学习,因此需要有更快的学习速率相比较其他层,因此我们将,weight和bias的学习速率加快10倍。
修改./models/bvlc_reference_caffenet/train_cal_resnet_lily.prototxt中 train和test对应的相关路径
mean_file: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/carmean.binaryproto
source: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/train_car_lmdb"
修改./models/bvlc_reference_caffenet/solver_resnet_lily.prototxt
net: "models/bvlc_reference_caffenet/train_val_resnet_lily.prototxt"
test_iter: 100
test_interval: 1000
base_lr: 0.001
lr_policy: "step"
gamma: 0.1
stepsize: 20000
display: 20
max_iter: 50000
momentum: 0.9
weight_decay: 0.0005
snapshot: 10000
snapshot_prefix: "models/bvlc_reference_caffenet/caffenet_resnet_model_lily"
solver_mode: GPU
原来是fc8,记得把跟fc8连接的名字都要修改掉,修改修改./models/bvlc_reference_caffenet/train_val_resnet_lily.prototxt 后如下
layer {
name: "fc8_comp_model"
type: "InnerProduct"
bottom: "fc7"
top: "fc8_comp_model"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 1000
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "accuracy"
type: "Accuracy"
bottom: "fc8_comp_model"
bottom: "label"
top: "accuracy"
include {
phase: TEST
}
}
layer {
name: "loss"
type: "SoftmaxWithLoss"
bottom: "fc8_comp_model"
bottom: "label"
top: "loss"
}
主要的调整有:test_iter从1000改为了100,因为数据量减少了,base_lr从0.01变成了0.001,这个很重要,微调时的基本学习速率不能太大,学习策略没有改变,步长从原来的100000变成了20000,最大的迭代次数也从450000变成了50000,动量和权重衰减项都没有修改,依然是GPU模型,网络模型文件和快照的路径根据自己修改
train_val_resnet_lily.prototxt完整文件为:
name: "CaffeNet"
layer {
name: "data"
type: "Data"
top: "data"
top: "label"
include {
phase: TRAIN
}
transform_param {
mirror: true
crop_size: 227
mean_file: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/carmean.binaryproto"
}
# mean pixel / channel-wise mean instead of mean image
# transform_param {
# crop_size: 227
# mean_value: 104
# mean_value: 117
# mean_value: 123
# mirror: true
# }
data_param {
source: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/train_car_lmdb"
batch_size: 256
backend: LMDB
}
}
layer {
name: "data"
type: "Data"
top: "data"
top: "label"
include {
phase: TEST
}
transform_param {
mirror: false
crop_size: 227
mean_file: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/carmean.binaryproto"
}
# mean pixel / channel-wise mean instead of mean image
# transform_param {
# crop_size: 227
# mean_value: 104
# mean_value: 117
# mean_value: 123
# mirror: false
# }
data_param {
source: "/media/***/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/data/cartest/train_car_lmdb"
batch_size: 50
backend: LMDB
}
}
layer {
name: "conv1"
type: "Convolution"
bottom: "data"
top: "conv1"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 96
kernel_size: 11
stride: 4
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "relu1"
type: "ReLU"
bottom: "conv1"
top: "conv1"
}
layer {
name: "pool1"
type: "Pooling"
bottom: "conv1"
top: "pool1"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "norm1"
type: "LRN"
bottom: "pool1"
top: "norm1"
lrn_param {
local_size: 5
alpha: 0.0001
beta: 0.75
}
}
layer {
name: "conv2"
type: "Convolution"
bottom: "norm1"
top: "conv2"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 256
pad: 2
kernel_size: 5
group: 2
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu2"
type: "ReLU"
bottom: "conv2"
top: "conv2"
}
layer {
name: "pool2"
type: "Pooling"
bottom: "conv2"
top: "pool2"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "norm2"
type: "LRN"
bottom: "pool2"
top: "norm2"
lrn_param {
local_size: 5
alpha: 0.0001
beta: 0.75
}
}
layer {
name: "conv3"
type: "Convolution"
bottom: "norm2"
top: "conv3"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 384
pad: 1
kernel_size: 3
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "relu3"
type: "ReLU"
bottom: "conv3"
top: "conv3"
}
layer {
name: "conv4"
type: "Convolution"
bottom: "conv3"
top: "conv4"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 384
pad: 1
kernel_size: 3
group: 2
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu4"
type: "ReLU"
bottom: "conv4"
top: "conv4"
}
layer {
name: "conv5"
type: "Convolution"
bottom: "conv4"
top: "conv5"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 256
pad: 1
kernel_size: 3
group: 2
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu5"
type: "ReLU"
bottom: "conv5"
top: "conv5"
}
layer {
name: "pool5"
type: "Pooling"
bottom: "conv5"
top: "pool5"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "fc6"
type: "InnerProduct"
bottom: "pool5"
top: "fc6"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 4096
weight_filler {
type: "gaussian"
std: 0.005
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu6"
type: "ReLU"
bottom: "fc6"
top: "fc6"
}
layer {
name: "drop6"
type: "Dropout"
bottom: "fc6"
top: "fc6"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "fc7"
type: "InnerProduct"
bottom: "fc6"
top: "fc7"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 4096
weight_filler {
type: "gaussian"
std: 0.005
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu7"
type: "ReLU"
bottom: "fc7"
top: "fc7"
}
layer {
name: "drop7"
type: "Dropout"
bottom: "fc7"
top: "fc7"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "fc8_comp_model"
type: "InnerProduct"
bottom: "fc7"
top: "fc8_comp_model"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 1000
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "accuracy"
type: "Accuracy"
bottom: "fc8_comp_model"
bottom: "label"
top: "accuracy"
include {
phase: TEST
}
}
layer {
name: "loss"
type: "SoftmaxWithLoss"
bottom: "fc8_comp_model"
bottom: "label"
top: "loss"
}
训练的指令如下:
./build/tools/caffe train --solver ./models/bvlc_reference_caffenet/solver_resnet_lily.prototxt --weights ./models/bvlc_reference_caffenet/bvlc_reference_caffenet.caffemodel --gpu 0
测试指令:
python ./python/classify02.py --model_def ./models/bvlc_reference_caffenet/train_val_test_resnet_lily.prototxt --pretrained_model ./models/bvlc_reference_caffenet/caffenet_resnet_model_lily_iter_50000.caffemodel --labels_file ./data/cartest/cartest.txt --center_only ./data/cartest/JPEGImages/crk201706301341.jpg foo
注意这里的train_val_test_resnet_lily.prototxt文件与训练时的文件train_val_resnet_lily.prototxt文件是不一样的。
train_val_resnet_lily.prototxt文件为:
name: "train_resnet_lily"
layer {
name: "data"
type: "Input"
top: "data"
input_param { shape: { dim: 1 dim: 3 dim: 227 dim: 227 } }
}
layer {
name: "conv1"
type: "Convolution"
bottom: "data"
top: "conv1"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 96
kernel_size: 11
stride: 4
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "relu1"
type: "ReLU"
bottom: "conv1"
top: "conv1"
}
layer {
name: "pool1"
type: "Pooling"
bottom: "conv1"
top: "pool1"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "norm1"
type: "LRN"
bottom: "pool1"
top: "norm1"
lrn_param {
local_size: 5
alpha: 0.0001
beta: 0.75
}
}
layer {
name: "conv2"
type: "Convolution"
bottom: "norm1"
top: "conv2"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 256
pad: 2
kernel_size: 5
group: 2
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu2"
type: "ReLU"
bottom: "conv2"
top: "conv2"
}
layer {
name: "pool2"
type: "Pooling"
bottom: "conv2"
top: "pool2"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "norm2"
type: "LRN"
bottom: "pool2"
top: "norm2"
lrn_param {
local_size: 5
alpha: 0.0001
beta: 0.75
}
}
layer {
name: "conv3"
type: "Convolution"
bottom: "norm2"
top: "conv3"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 384
pad: 1
kernel_size: 3
weight_filler {
type: "gaussian"
std: 0.01
}
bias_filler {
type: "constant"
value: 0
}
}
}
layer {
name: "relu3"
type: "ReLU"
bottom: "conv3"
top: "conv3"
}
layer {
name: "conv4"
type: "Convolution"
bottom: "conv3"
top: "conv4"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 384
pad: 1
kernel_size: 3
group: 2
}
}
layer {
name: "relu4"
type: "ReLU"
bottom: "conv4"
top: "conv4"
}
layer {
name: "conv5"
type: "Convolution"
bottom: "conv4"
top: "conv5"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
convolution_param {
num_output: 256
pad: 1
kernel_size: 3
group: 2
}
}
layer {
name: "relu5"
type: "ReLU"
bottom: "conv5"
top: "conv5"
}
layer {
name: "pool5"
type: "Pooling"
bottom: "conv5"
top: "pool5"
pooling_param {
pool: MAX
kernel_size: 3
stride: 2
}
}
layer {
name: "fc6"
type: "InnerProduct"
bottom: "pool5"
top: "fc6"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 4096
weight_filler {
type: "gaussian"
std: 0.005
}
bias_filler {
type: "constant"
value: 1
}
}
}
layer {
name: "relu6"
type: "ReLU"
bottom: "fc6"
top: "fc6"
}
layer {
name: "drop6"
type: "Dropout"
bottom: "fc6"
top: "fc6"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "fc7"
type: "InnerProduct"
bottom: "fc6"
top: "fc7"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 4096
}
}
layer {
name: "relu7"
type: "ReLU"
bottom: "fc7"
top: "fc7"
}
layer {
name: "drop7"
type: "Dropout"
bottom: "fc7"
top: "fc7"
dropout_param {
dropout_ratio: 0.5
}
}
layer {
name: "fc8_comp_model"
type: "InnerProduct"
bottom: "fc7"
top: "fc8_comp_model"
param {
lr_mult: 1
decay_mult: 1
}
param {
lr_mult: 2
decay_mult: 0
}
inner_product_param {
num_output: 1000
}
}
layer {
name: "prob"
type: "Softmax"
bottom: "fc8_comp_model"
top: "prob"
}
报错及解决方案
在最后一步测试的时候运行报错
报错:
File "python/classify.py", line 138, in
main(sys.argv)
File "python/classify.py", line 110, in main
channel_swap=channel_swap)
File "/media/futurus/801328a5-39c6-4e08-b070-19fc662a5236/resnet/caffe/python/caffe/classifier.py", line 29, in __init__
in_ = self.inputs[0]
IndexError: list index out of range
参考解决方案;
加入:
net: "train_resnet_lily"
input: "data"
input_shape {
dim: 10
dim: 3
dim: 224
dim: 224
}
加入之后 又报了其他错误:
[libprotobuf ERROR google/protobuf/text_format.cc:274] Error parsing text-format caffe.NetParameter: 1:4: Message type "caffe.NetParameter" has no field named "net".
F0125 11:48:14.708683 42586 upgrade_proto.cpp:88] Check failed: ReadProtoFromTextFile(param_file, param) Failed to parse NetParameter file: ./models/bvlc_reference_caffenet/train_val_test_resnet_lily.prototxt
*** Check failure stack trace: ***
Aborted (core dumped)
根据网友的博客修改加入为
net: "train_resnet_lily"
input: "data"
input_dim: 10
input_dim: 3
input_dim: 224
input_dim: 224
测试还不不行,还是报错。
最终解决方案如下,运行通过。加入
name: "train_resnet_lily"
layer {
name: "data"
type: "Input"
top: "data"
input_param { shape: { dim: 1 dim: 3 dim: 227 dim: 227 } }
}
Reference:
https://www.cnblogs.com/louyihang-loves-baiyan/p/5038758.html
http://blog.csdn.net/sunshine_in_moon/article/details/49472901