leNET算是caffe学习的第一个例子了,例子来源于caffe官网:http://caffe.berkeleyvision.org/gathered/examples/mnist.html
接口部分都用python写好,所以只跑跑例子的话可以先不看cpp代码
1.根据路径,我们先看总配置文件
cd $CAFFE_ROOT
./examples/mnist/train_lenet.sh
2.打开之后,我们可以看到就两行
#!/usr/bin/env sh
./build/tools/caffe train –solver=examples/mnist/lenet_solver.prototxt(依赖配置文件)
我这里叫 lenet_solver.prototxt 依赖配置文件吧,关键是solver.prototxt
3.然后打开依赖配置文件
# The train/test net protocol buffer definition(制定训练和测试模型)
net: "examples/mnist/lenet_train_test.prototxt"(网络配置文件位置)
# test_iter specifies how many forward passes the test should carry out.
# In the case of MNIST, we have test batch size 100 and 100 test iterations,
# covering the full 10,000 testing images.
test_iter: 100 (1次100个测试集样本参与向前计算)
# Carry out testing every 500 training iterations.
test_interval: 500 (每训练500次进行一次测试)
# The base learning rate, momentum and the weight decay of the network.
base_lr: 0.01 (基础学习率)
momentum: 0.9 (动量)
weight_decay: 0.0005 (权重衰减)
# The learning rate policy (学习策略)
lr_policy: "inv" (inv: return base_lr * (1 + gamma * iter) ^ (- power))
gamma: 0.0001
power: 0.75
# Display every 100 iterations
display: 100() (每迭代100次打印结果)
# The maximum number of iterations
max_iter: 10000 (最大迭代次数)
# snapshot intermediate results
snapshot: 5000 (5000次迭代保存一次临时模型,名称为lenet_iter_5000.caffemodel)
snapshot_prefix: "examples/mnist/lenet"
# solver mode: CPU or GPU
solver_mode: GPU (GPU开关)
看到lenet_train_test.prototxt"(我就叫做网络配置文件吧,里面存放的是网络结构)
4.我们打开网络结构的这个文件
name: "LeNet" 网络名
layer {
name: "mnist" 本层名称
type: "Data" 层类型
top: "data" 下一层接口
top: "label" 下一层接口
include {
phase: TRAIN
}
transform_param {
scale: 0.00390625 #1/256,预处理如减均值,尺寸变换,随机剪,镜像等
}
data_param {
source: "examples/mnist/mnist_train_lmdb" 训练数据位置
batch_size: 64 一次训练的样本数
backend: LMDB 读入的训练数据格式,默认leveldb
}
}
layer {
name: "mnist"
type: "Data"
top: "data"
top: "label"
include {
phase: TEST
}
transform_param {
scale: 0.00390625
}
data_param {
source: "examples/mnist/mnist_test_lmdb"
batch_size: 100 一次测试使用100个数据
backend: LMDB
}
}
layer {
name: "conv1"
type: "Convolution" 卷积层
bottom: "data" 上一层名“data”
top: "conv1" 下一层接口“conv1”
param {
lr_mult: 1 (weights的学习率与全局相同)
}
param {
lr_mult: 2 (biases的学习率是全局的2倍)
}
convolution_param {
num_output: 20 卷积核20个
kernel_size: 5 卷积核尺寸5×5
stride: 1 步长1
weight_filler {
type: "xavier" (随机的初始化权重和偏差)
}
bias_filler {
type: "constant" bias用0初始化
}
}
}
layer {
name: "pool1"
type: "Pooling" 池化层
bottom: "conv1" 上层“conv1”
top: "pool1" 下层接口“pool1”
pooling_param {
pool: MAX 池化函数用MAX
kernel_size: 2 池化核函数大小2×2
stride: 2 步长2
}
}
layer {
name: "conv2"
type: "Convolution"
bottom: "pool1"
top: "conv2"
param {
lr_mult: 1
}
param {
lr_mult: 2
}
convolution_param {
num_output: 50 卷积核50个
kernel_size: 5
stride: 1
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}
}
layer {
name: "pool2"
type: "Pooling"
bottom: "conv2"
top: "pool2"
pooling_param {
pool: MAX
kernel_size: 2
stride: 2
}
}
layer {
name: "ip1"
type: "InnerProduct" 全连接层
bottom: "pool2" 上层连接“pool2”
top: "ip1" “下层输出接口ip1”
param {
lr_mult: 1
}
param {
lr_mult: 2
}
inner_product_param {
num_output: 500 输出数量500
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}
}
layer {
name: "relu1"
type: "ReLU" 激活函数
bottom: "ip1"
top: "ip1" (这个地方还是ip1,底层与顶层相同减少开支,下一层全连接层的输入也还是ip1)
}
layer {
name: "ip2"
type: "InnerProduct"
bottom: "ip1"
top: "ip2"
param {
lr_mult: 1
}
param {
lr_mult: 2
}
inner_product_param {
num_output: 10 输出结果10个
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}
}
layer {
name: "accuracy"
type: "Accuracy"
bottom: "ip2" 上层连接ip2全连接层
bottom: "label" 上层连接label层
top: "accuracy" 输出接口为accuracy
include {
phase: TEST
}
}
layer {
name: "loss"
type: "SoftmaxWithLoss" 损失函数
bottom: "ip2"
bottom: "label"
top: "loss"
}
其实我这里偷懒了,因为我一开始仔细学习的网络文件不是这个,而是另一个,下面我把详细备注的网络文件放上来
name: "LeNet"(网络的名字)
layer {
name: "data"
type: "Input"(层类型,输入)
top: "data"(导入数据这一层没有bottom,因为是第一层)
input_param { shape: { dim: 64 dim: 1 dim: 28 dim: 28 } }(64张图为一批,28*28大小)
}
读取这批数据维度:64 1 28 28
layer {
name: "conv1"
type: "Convolution"(卷积类型层)
bottom: "data"(上一层名叫做data)
top: "conv1"(下一层名叫做conv1)
param {
lr_mult: 1(weights的学习率与全局相同)
}
param {
lr_mult: 2(biases的学习率是全局的2倍)
}
convolution_param {(卷积操作参数设置)
num_output: 20(卷积输出数量20,由20个特征图Feature Map构成)
kernel_size: 5(卷积核的大小是5*5)
stride: 1(卷积操作步长)
weight_filler {
type: "xavier"(随机的初始化权重和偏差)
}
bias_filler {
type: "constant"(bias使用0初始化)
}
}(通过卷积之后,数据变成(28-5+1)*(28-5+1),20个特征)
}
卷积之后这批数据维度:64 20 24 24
layer {
name: "pool1"
type: "Pooling"(下采样类型层)
bottom: "conv1"
top: "pool1"
pooling_param {
pool: MAX(下采样方式,取最大值)
kernel_size: 2(下采样核函数size)
stride: 2(步长)
}
}
下采样之后这批数据维度:64 20 12 12
layer {
name: "conv2"
type: "Convolution"
bottom: "pool1"
top: "conv2"
param {
lr_mult: 1
}
param {
lr_mult: 2
}
convolution_param {
num_output: 50(50个卷积核)
kernel_size: 5
stride: 1
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}
}
卷积之后这批数据维度:64 50 8 8
layer {
name: "pool2"
type: "Pooling"
bottom: "conv2"
top: "pool2"
pooling_param {
pool: MAX
kernel_size: 2
stride: 2
}
}
下采样之后这批数据维度:64 50 4 4
layer {
name: "ip1"
type: "InnerProduct"(全连接类型层)
bottom: "pool2"
top: "ip1"
param {
lr_mult: 1
}
param {
lr_mult: 2
}
inner_product_param {(全连接层参数设置)
num_output: 500(输出为500)
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}(4*4的数据通过4*4的卷积得到1*1的数据)
}
通过全连接层之后这批数据维度:64 500 1 1
layer {
name: "relu1"
type: "ReLU"(激活函数类型层)
bottom: "ip1"
top: "ip1"(这个地方还是ip1,底层与顶层相同减少开支,下一层全连接层的输入也还是ip1)
}
通过ReLU层之后这批数据维度:64 500 1 1(不做改变)
layer {
name: "ip2"
type: "InnerProduct"
bottom: "ip1"
top: "ip2"
param {
lr_mult: 1
}
param {
lr_mult: 2
}
inner_product_param {
num_output: 10(直接输出结果,0-9,十个数字所以维度是10)
weight_filler {
type: "xavier"
}
bias_filler {
type: "constant"
}
}(数据的分类判断在这一层中完成)
}
通过全连接层之后这批数据维度:64 10 1 1
layer {
name: "prob"
type: "Softmax"(损失函数)
bottom: "ip2"
top: "prob"(一开始数据输入为date的话,这里写label)
}
要注意激活层那里的输入和输出都是一个口子,为的是节省资源
暂时先这么写了,因为重点是要做图像的,现在在看如何将jpg变成lmdb,然后自己写网络跑通论文的代码,以上信息如有不正确的地方请指正,3Q