mmclassification/mmcls/models/utils/se_layer.py

31 lines
867 B
Python

import torch.nn as nn
class SELayer(nn.Module):
"""Squeeze-and-Excitation Module.
Args:
inplanes (int): The input channels of the SEBottleneck block.
ratio (int): Squeeze ratio in SELayer. Default: 16
"""
def __init__(self, inplanes, ratio=16):
super(SELayer, self).__init__()
self.global_avgpool = nn.AdaptiveAvgPool2d(1)
self.conv1 = nn.Conv2d(
inplanes, int(inplanes / ratio), kernel_size=1, stride=1)
self.conv2 = nn.Conv2d(
int(inplanes / ratio), inplanes, kernel_size=1, stride=1)
self.relu = nn.ReLU(inplace=True)
self.sigmoid = nn.Sigmoid()
def forward(self, x):
out = self.global_avgpool(x)
out = self.conv1(out)
out = self.relu(out)
out = self.conv2(out)
out = self.sigmoid(out)
return x * out