pytorch实现resnet_如何搭建平台

import torch
import torch.nn as nn
from torch.nn import functional as F
class CommonBlock(nn.Module):
def __init__(self, in_channel, out_channel, stride):
super(CommonBlock, self).__init__()
self.conv1 = nn.Conv2d(in_channel, out_channel, kernel_size=3, stride=stride, padding=1, bias=False)
self.bn1 = nn.BatchNorm2d(out_channel)
self.conv2 = nn.Conv2d(out_channel, out_channel, kernel_size=3, stride=stride, padding=1, bias=False)
self.bn2 = nn.BatchNorm2d(out_channel)
def forward(self, x):
identity = x
x = F.relu(self.bn1(self.conv1(x)), inplace=True)
x = self.bn2(self.conv2(x))
x += identity
return F.relu(x, inplace=True)
class SpecialBlock(nn.Module):
def __init__(self, in_channel, out_channel, stride):
super(SpecialBlock, self).__init__()
self.change_channel = nn.Sequential(
nn.Conv2d(in_channel, out_channel, kernel_size=1, stride=stride[0], padding=0, bias=False),
nn.BatchNorm2d(out_channel)
)
self.conv1 = nn.Conv2d(in_channel, out_channel, kernel_size=3, stride=stride[0], padding=1, bias=False)
self.bn1 = nn.BatchNorm2d(out_channel)
self.conv2 = nn.Conv2d(out_channel, out_channel, kernel_size=3, stride=stride[1], padding=1, bias=False)
self.bn2 = nn.BatchNorm2d(out_channel)
def forward(self, x):
identity = self.change_channel(x)
x = F.relu(self.bn1(self.conv1(x)), inplace=True)
x = self.bn2(self.conv2(x))
x += identity
return F.relu(x, inplace=True)
class ResNet34(nn.Module):
def __init__(self, classes_num):
super(ResNet34, self).__init__()
self.prepare = nn.Sequential(
nn.Conv2d(3, 64, 7, 2, 3),
nn.BatchNorm2d(64),
nn.ReLU(inplace=True),
nn.MaxPool2d(3, 2, 1)
)
self.layer1 = nn.Sequential(
CommonBlock(64, 64, 1),
CommonBlock(64, 64, 1),
CommonBlock(64, 64, 1)
)
self.layer2 = nn.Sequential(
SpecialBlock(64, 128, [2, 1]),
CommonBlock(128, 128, 1),
CommonBlock(128, 128, 1),
CommonBlock(128, 128, 1)
)
self.layer3 = nn.Sequential(
SpecialBlock(128, 256, [2, 1]),
CommonBlock(256, 256, 1),
CommonBlock(256, 256, 1),
CommonBlock(256, 256, 1),
CommonBlock(256, 256, 1),
CommonBlock(256, 256, 1)
)
self.layer4 = nn.Sequential(
SpecialBlock(256, 512, [2, 1]),
CommonBlock(512, 512, 1),
CommonBlock(512, 512, 1)
)
self.pool = nn.AdaptiveAvgPool2d(output_size=(1, 1))
self.fc = nn.Sequential(
nn.Dropout(p=0.5),
nn.Linear(512, 256),
nn.ReLU(inplace=True),
nn.Dropout(p=0.5),
nn.Linear(256, classes_num)
)
def forward(self, x):
x = self.prepare(x)
x = self.layer1(x)
x = self.layer2(x)
x = self.layer3(x)
x = self.layer4(x)
x = self.pool(x)
x = x.reshape(x.shape[0], -1)
x = self.fc(x)
return x