diff --git a/model_improved_alexnet_plus.py b/model_improved_alexnet_plus.py new file mode 100644 index 0000000..4666dd8 --- /dev/null +++ b/model_improved_alexnet_plus.py @@ -0,0 +1,99 @@ +import torch.nn as nn +import torch +import torch +import torch.nn as nn +import torch.nn.functional as F + +class SE_block(nn.Module): + def __init__(self, inchannel, ratio = 16):#压缩比默认16 + super(SE_block, self).__init__() + #全局平均池化 + self.gap = nn.AdaptiveAvgPool2d((1,1)) + #两个全连接层 + self.fc = nn.Sequential( + nn.Linear(inchannel, inchannel // ratio, bias = False), + nn.ReLU(), + nn.Linear(inchannel // ratio, inchannel, bias=False), + nn.Sigmoid() + ) + + def forward(self, x): + b ,c ,h ,w =x.size()#读取数据图片数量和通道数 + #print(b, c, h, w) (32, 128, 27, 27) + y = self.gap(x).view(b ,c)#经过池化后输出b*c的矩阵 + y =self.fc(y).view(b ,c, 1, 1)#经过全连接层输出(b,c,1,1)矩阵 + + return x * y.expand_as(x)#将得到的权重*原来的特征图x + + +class InceptionModule(nn.Module): + def __init__(self, in_channels, out_1x1, reduce_3x3, out_3x3, reduce_5x5, out_5x5, out_pool_proj): + super(InceptionModule, self).__init__() + + #分支1:1*1卷积层 + self.branch1 = nn.Sequential( + nn.Conv2d(in_channels, out_1x1, kernel_size=1), + nn.ReLU(True), + ) + + #分支2:1*1卷积层 3*3卷积层 + self.branch2 = nn.Sequential( + nn.Conv2d(in_channels, reduce_3x3, kernel_size=1), + nn.ReLU(True), + nn.Conv2d(reduce_3x3, out_3x3, kernel_size=3, padding=1), + nn.ReLU(True), + ) + + #分支3:1*1卷积层 5*5卷积层 + self.branch3 = nn.Sequential( + nn.Conv2d(in_channels, reduce_5x5, kernel_size=1), + nn.ReLU(True), + nn.Conv2d(reduce_5x5, out_5x5, kernel_size=5, padding=2), + nn.ReLU(True), + ) + + #分支4:3*3最大池化层 1*1卷积层 + self.branch4 = nn.Sequential( + nn.MaxPool2d(kernel_size=3, stride=1, padding=1), + nn.Conv2d(in_channels, out_pool_proj, kernel_size=1), + nn.ReLU(True), + ) + + #进行concatenate连接,将四个分支合并一起作为输出 + def forward(self, x): + outputs = [self.branch1(x), self.branch2(x), self.branch3(x), self.branch4(x)] + return torch.cat(outputs, 1) + + +class ImprovedAlexNet(nn.Module): + def __init__(self, num_classes=1000): + super(ImprovedAlexNet, self).__init__() + self.features = nn.Sequential( + nn.Conv2d(3, 64, kernel_size=11, stride=4, padding=2),#卷积层1 + nn.ReLU(inplace=True),#激活函数 + nn.MaxPool2d(kernel_size=3, stride=2),#最大池化层1 + SE_block(64), + InceptionModule(64, 32, 48, 64, 8, 16, 16), # 替代原始的第一个卷积层 + nn.MaxPool2d(kernel_size=3, stride=2),#最大池化层2 + #SE_block(128), + InceptionModule(128, 64, 96, 128, 16, 32, 32), # 替代原始的第二个卷积层 + nn.MaxPool2d(kernel_size=3, stride=2),#最大池化层3 + ) + self.classifier = nn.Sequential( + nn.Dropout(p=0.5),#Dropout层,表示对输入数据进行随机丢弃操作,丢弃概率为0.5,用于防止过拟合 + nn.Linear(256 * 6 * 6, 2048),#全连接层,将输入特征的维度由(256,6,6)转换为2048,用于进行线性变换操作 + #nn.Linear(128 * 13 * 13, 2048), + nn.ReLU(inplace=True),#激活函数 + nn.Dropout(p=0.5),#Dropout层,作用同上 + nn.Linear(2048, 2048),#全连接层 + nn.ReLU(inplace=True),#激活函数 + nn.Linear(2048, num_classes),#全连接层 + ) + + def forward(self, x): + x = self.features(x)#进行卷积操作 + #print(x.shape) + x = torch.flatten(x, start_dim=1)#展平 + x = self.classifier(x)#输出 + return x +