# encoding: utf-8 """ @author: liaoxingyu @contact: sherlockliao01@gmail.com """ from torch import nn class SELayer(nn.Module): def __init__(self, channel, reduction=16): super(SELayer, self).__init__() self.avg_pool = nn.AdaptiveAvgPool2d(1) self.fc = nn.Sequential( nn.Linear(channel, int(channel / reduction), bias=False), nn.ReLU(inplace=True), nn.Linear(int(channel / reduction), channel, bias=False), nn.Sigmoid() ) def forward(self, x): b, c, _, _ = x.size() y = self.avg_pool(x).view(b, c) y = self.fc(y).view(b, c, 1, 1) return x * y.expand_as(x)