resnet模型代码
时间: 2024-10-13 13:03:52 浏览: 29
ResNet(Residual Network)是一种深度卷积神经网络,由Kaiming He等人于2015年提出,主要用于解决深度学习训练过程中的梯度消失和过拟合问题。它的核心思想是在网络中引入残差块(residual block),使得信息可以更容易地从输入层传播到输出层,无需经过那么多层直接进行跳跃。
以下是简单的ResNet模型代码结构概述(这里使用的是PyTorch框架的伪代码):
```python
class ResidualBlock(nn.Module):
def __init__(self, in_channels, out_channels, stride=1):
super().__init__()
self.conv1 = nn.Conv2d(in_channels, out_channels, kernel_size=3, padding=1, stride=stride)
self.bn1 = nn.BatchNorm2d(out_channels)
self.relu = nn.ReLU(inplace=True)
self.conv2 = nn.Conv2d(out_channels, out_channels, kernel_size=3, padding=1)
self.bn2 = nn.BatchNorm2d(out_channels)
self.shortcut = (nn.Sequential(
nn.Conv2d(in_channels, out_channels, kernel_size=1, stride=stride),
nn.BatchNorm2d(out_channels)
) if stride != 1 or in_channels != out_channels else nn.Identity())
def forward(self, x):
residual = x
out = self.conv1(x)
out = self.bn1(out)
out = self.relu(out)
out = self.conv2(out)
out = self.bn2(out)
return self.relu(out + self.shortcut(residual))
# 示例创建一个基本的ResNet-18模型
def create_resnet18(num_classes):
model = nn.Sequential(
... # 初始化一系列的ResidualBlock,并连接起来形成整个网络
nn.AdaptiveAvgPool2d((1, 1)),
nn.Flatten(),
nn.Linear(512, num_classes) # 最后的全连接层,512是ResNet的一个常用输出通道数
)
return model
```
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