InceptionV4 Inception-ResNet 论文研读及Pytorch代码复现

InceptionV4 Inception-ResNet 论文研读及Pytorch代码复现

论文地址: Inception-v4, Inception-ResNet and the Impact of Residual Connections on Learning

文章最大的贡献就是在Inception引入残差结构后,研究了残差结构对Inception的影响,得到的结论是,残差结构的引入可以加快训练速度,但是在参数量大致相同的Inception v4(纯Inception,无残差连接)模型和Inception-ResNet-v2(有残差连接),其识别效果大致相同,只是训练速度稍有不同。并且文章最后指出,其最新模型InceptionV4模型优于之前的所有模型,仅仅是因为增加了模型大小

1 相关工作

该部分第二段,稍微总结了Inception的发展创新点,Inception就是最原始的GoogleNet,于2015年提出,之后在GoogleNet中添加BN层,形成了InceptionV2模型;再然后,针对Inception中卷积操作进行改善,例如分解大卷积核(两个33卷积核替换原先的一个55卷进核)、将卷积核沿深度展开(用17和71串行卷积替换原先的77卷积核)、将卷积核沿长度方向展开(使用31和13卷积核替换原先的33卷积核)

2 模型构建

2.1 Inception V4:

该模型有8个主要结构构成,这也就是论文中到处都是图的原因,需要认真看,以下是将主干图和分解图放在一起,可以看模块输出后大小,用来辅助理解!!

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Stem Block:

# 定义一个卷积模块(带BatchNormalization及ReLU激活函数)
class BasicConv2d(nn.Module):
    def __init__(self, in_channels, out_channels, **kwargs):
        super(BasicConv2d, self).__init__()
        self.conv = nn.Conv2d(in_channels, out_channels, **kwargs)
        self.bn = nn.BatchNorm2d(out_channels)
        
    def forward(self, x):
        x = self.conv(x)
        x = self.bn(x)
        return F.relu(x)

class Stem(nn.Module):
    def __init__(self, in_channels, out_channels):
        super(Stem, self).__init__()
        #conv3*3(32 stride2 valid)
        self.conv1 = BasicConv2d(in_channels, 32, kernel_size=3, stride=2)
        #conv3*3(32 valid)
        self.conv2 = BasicConv2d(32, 32, kernel_size=3)
        #conv3*3(64)
        self.conv3 = BasicConv2d(32, 64, kernel_size=3, padding=1)
        #maxpool3*3(stride2 valid) & conv3*3(96 stride2 valid)
        self.maxpool4 = nn.MaxPool2d(kernel_size=3, stride=2)
        self.conv4 = BasicConv2d(64, 96, kernel_size=3, stride=2)
        
        #conv1*1(64) --> conv3*3(96 valid)
        self.conv5_1_1 = BasicConv2d(160, 64, kernel_size=1)
        self.conv5_1_2 = BasicConv2d(64, 96, kernel_size=3)
        #conv1*1(64) --> conv7*1(64) --> conv1*7(64) --> conv3*3(96 valid)
        self.conv5_2_1 = BasicConv2d(160, 64, kernel_size=1)
        self.conv5_2_2 = BasicConv2d(64, 64, kernel_size=(7,1), padding=(3,0))
        self.conv5_2_3 = BasicConv2d(64, 64, kernel_size=(1,7), padding=(0,3))
        self.conv5_2_4 = BasicConv2d(64, 96, kernel_size=3)
        
        #conv3*3(192 valid)
        self.conv6 = BasicConv2d(192, 192, kernel_size=3, stride=2)
        #maxpool3*3(stride2 valid)
        self.maxpool6 = nn.MaxPool2d(kernel_size=3, stride=2)
        
    def forward(self, x):
        y1_1 = self.maxpool4(self.conv3(self.conv2(self.conv1(x))))
        y1_2 = self.conv4(self.conv3(self.conv2(self.conv1(x))))
        y1 = torch.cat([y1_1, y1_2], 1)
        
        y2_1 = self.conv5_1_2(self.conv5_1_1(y1))
        y2_2 = self.conv5_2_4(self.conv5_2_3(self.conv5_2_2(self.conv5_2_1(y1))))
        y2 = torch.cat([y2_1, y2_2], 1)
        
        y3_1 = self.conv6(y2)
        y3_2 = self.maxpool6(y2)
        y3 = torch.cat([y3_1, y3_2], 1)
        
        return y3

Inception-A Block

class InceptionA(nn.Module):
    def __init__(self, in_channels, out_channels):
        super(InceptionA, self).__init__()
        #branch1: avgpool --> conv1*1(96)
        self.b1_1 = nn.AvgPool2d(kernel_size=3, padding=1, stride=1)
        self.b1_2 = BasicConv2d(in_channels, 96, kernel_size=1)
        
        #branch2: conv1*1(96)
        self.b2 = BasicConv2d(in_channels, 96, kernel_size=1)
        
        #branch3: conv1*1(64) --> conv3*3(96)
        self.b3_1 = BasicConv2d(in_channels, 64, kernel_size=1)
        self.b3_2 = BasicConv2d(64, 96, kernel_size=3, padding=1)
        
        #branch4: conv1*1(64) --> conv3*3(96) --> conv3*3(96)
        self.b4_1 = BasicConv2d(in_channels, 64, kernel_size=1)
        self.b4_2 = BasicConv2d(64, 96, kernel_size=3, padding=1)
        self.b4_3 = BasicConv2d(96, 96, kernel_size=3, padding=1)
        
    def forward(self, x):
        y1 = self.b1_2(self.b1_1(x))
        y2 = self.b2(x)
        y3 = self.b3_2(self.b3_1(x))
        y4 = self.b4_3(self.b4_2(self.b4_1(x)))
        
        outputsA = [y1, y2, y3, y4]
        return torch.cat(outputsA, 1)

Inception-B Block

class InceptionB(nn.Module):
    def __init__(self, in_channels, out_channels):
        super(InceptionB, self).__init__()
        #branch1: avgpool --> conv1*1(128)
        self.b1_1 = nn.AvgPool2d(kernel_size=3, padding=1, stride=1)
        self.b1_2 = BasicConv2d(in_channels, 128, kernel_size=1)
        
        #branch2: conv1*1(384)
        self.b2 = BasicConv2d(in_channels, 384, kernel_size=1)
        
        #branch3: conv1*1(192) --> conv1*7(224) --> conv1*7(256)
        self.b3_1 = BasicConv2d(in_channels, 192, kernel_size=1)
        self.b3_2 = BasicConv2d(192, 224, kernel_size=(7,1), padding=(3,0))
        self.b3_3 = BasicConv2d(224, 256, kernel_size=(1,7), padding=(0,3))
        
        #branch4: conv1*1(192) --> conv1*7(192) --> conv7*1(224) --> conv1*7(224) --> conv7*1(256)
        self.b4_1 = BasicConv2d(in_channels, 192, kernel_size=1, stride=1)
        self.b4_2 = BasicConv2d(192, 192, kernel_size=(1,7), padding=(0,3))
        self.b4_3 = BasicConv2d(192, 224, kernel_size=(7,1), padding=(3,0))
        self.b4_4 = BasicConv2d(224, 224, kernel_size=(1,7), padding=(0,3))
        self.b4_5 = BasicConv2d(224, 256, kernel_size=(7,1), padding=(3,0))
        
    def forward(self, x):
        y1 = self.b1_2(self.b1_1(x))
        y2 = self.b2(x)
        y3 = self.b3_3(self.b3_2(self.b3_1(x)))
        y4 = self.b4_5(self.b4_4(self.b4_3(self.b4_2(self.b4_1(x)))))
        
        outputsB = [y1, y2, y3, y4]
        return torch.cat(outputsB, 1)

Inception-C Block

class InceptionC(nn.Module):
    def __init__(self, in_channels, out_channels):
        super(InceptionC, self).__init__()
        #branch1: avgpool --> conv1*1(256)
        self.b1_1 = nn.AvgPool2d(kernel_size=3, padding=1, stride=1)
        self.b1_2 = BasicConv2d(in_channels, 256, kernel_size=1)
        
        #branch2: conv1*1(256)
        self.b2 = BasicConv2d(in_channels, 256, kernel_size=1)
        
        #branch3: conv1*1(384) --> conv1*3(256) & conv3*1(256)
        self.b3_1 = BasicConv2d(in_channels, 384, kernel_size=1)
        self.b3_2_1 = BasicConv2d(384, 256, kernel_size=(1,3), padding=(0,1))
        self.b3_2_2 = BasicConv2d(384, 256, kernel_size=(3,1), padding=(1,0))
        
        #branch4: conv1*1(384) --> conv1*3(448) --> conv3*1(512) --> conv3*1(256) & conv7*1(256)
        self.b4_1 = BasicConv2d(in_channels, 384, kernel_size=1, stride=1)
        self.b4_2 = BasicConv2d(384, 448, kernel_size=(1,3), padding=(0,1))
        self.b4_3 = BasicConv2d(448, 512, kernel_size=(3,1), padding=(1,0))
        self.b4_4_1 = BasicConv2d(512, 256, kernel_size=(3,1), padding=(1,0))
        self.b4_4_2 = BasicConv2d(512, 256, kernel_size=(1,3), padding=(0,1))
        
    def forward(self, x):
        y1 = self.b1_2(self.b1_1(x))
        y2 = self.b2(x)
        y3_1 = self.b3_2_1(self.b3_1(x))
        y3_2 = self.b3_2_2(self.b3_1(x))
        y4_1 = self.b4_4_1(self.b4_3(self.b4_2(self.b4_1(x))))
        y4_2 = self.b4_4_2(self.b4_3(self.b4_2(self.b4_1(x))))
        
        outputsC = [y1, y2, y3_1, y3_2, y4_1, y4_2]
        return torch.cat(outputsC, 1)

ReductionA Block

class ReductionA(nn.Module):
    def __init__(self, in_channels, out_channels, k, l, m, n):
        super(ReductionA, self).__init__()
        #branch1: maxpool3*3(stride2 valid)
        self.b1 = nn.MaxPool2d(kernel_size=3, stride=2)
        
        #branch2: conv3*3(n stride2 valid)
        self.b2 = BasicConv2d(in_channels, n, kernel_size=3, stride=2)
        
        #branch3: conv1*1(k) --> conv3*3(l) --> conv3*3(m stride2 valid)
        self.b3_1 = BasicConv2d(in_channels, k, kernel_size=1)
        self.b3_2 = BasicConv2d(k, l, kernel_size=3, padding=1)
        self.b3_3 = BasicConv2d(l, m, kernel_size=3, stride=2)
        
    def forward(self, x):
        y1 = self.b1(x)
        y2 = self.b2(x)
        y3 = self.b3_3(self.b3_2(self.b3_1(x)))
        
        outputsRedA = [y1, y2, y3]
        return torch.cat(outputsRedA, 1)

ReductionB Block

class ReductionB(nn.Module):
    def __init__(self, in_channels, out_channels):
        super(ReductionB, self).__init__()
        #branch1: maxpool3*3(stride2 valid)
        self.b1 = nn.MaxPool2d(kernel_size=3, stride=2)
        
        #branch2: conv1*1(192) --> conv3*3(192 stride2 valid)
        self.b2_1 = BasicConv2d(in_channels, 192, kernel_size=1)
        self.b2_2 = BasicConv2d(192, 192, kernel_size=3, stride=2)
        
        #branch3: conv1*1(256) --> conv1*7(256) --> conv7*1(320) --> conv3*3(320 stride2 valid)
        self.b3_1 = BasicConv2d(in_channels, 256, kernel_size=1)
        self.b3_2 = BasicConv2d(256, 256, kernel_size=(1,7), padding=(0,3))
        self.b3_3 = BasicConv2d(256, 320, kernel_size=(7,1), padding=(3,0))
        self.b3_4 = BasicConv2d(320, 320, kernel_size=3, stride=2)
        
    def forward(self, x):
        y1 = self.b1(x)
        y2 = self.b2_2(self.b2_1((x)))
        y3 = self.b3_4(self.b3_3(self.b3_2(self.b3_1(x))))
        
        outputsRedB = [y1, y2, y3]
        return torch.cat(outputsRedB, 1)

Inception V4网络

class Googlenetv4(nn.Module):   # 这里默认了输入通道是3,输出是1000,有需要的话,可以自己改一下
    def __init__(self):
        super(Googlenetv4, self).__init__()
        self.stem = Stem(3, 384)
        self.icpA = InceptionA(384, 384)
        self.redA = ReductionA(384, 1024, 192, 224, 256, 384)
        self.icpB = InceptionB(1024, 1024)
        self.redB = ReductionB(1024, 1536)
        self.icpC = InceptionC(1536, 1536)
        self.avgpool = nn.AvgPool2d(kernel_size=8)
        self.dropout = nn.Dropout(p=0.8)
        self.linear = nn.Linear(1536, 1000)
        
    def forward(self, x):
        #Stem Module
        out = self.stem(x)
        #InceptionA Module * 4
        out = self.icpA(self.icpA(self.icpA(self.icpA(out))))
        #ReductionA Module
        out = self.redA(out)
        #InceptionB Module * 7
        out = self.icpB(self.icpB(self.icpB(self.icpB(self.icpB(self.icpB(self.icpB(out)))))))
        #ReductionB Module
        out = self.redB(out)
        #InceptionC Module * 3
        out = self.icpC(self.icpC(self.icpC(out)))
        #Average Pooling
        out = self.avgpool(out)
        out = out.view(out.size(0), -1)
        #Dropout
        out = self.dropout(out)
        #Linear(Softmax)
        out = self.linear(out)
        
        return out

2.2 Inception-ResNet:

Inception-ResNet网络一共有两个版本,v1对标Inception V3,v2对标Inception V4,但是主体结构不变,主要是底层模块过滤器使用的不同,以下给出主体结构和相关代码
Inception-ResNet v1网络结构
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Inception-ResNet v2网络结构
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from __future__ import print_function, division, absolute_import
import torch
import torch.nn as nn
import torch.utils.model_zoo as model_zoo
import os
import sys

__all__ = ['InceptionResNetV2', 'inceptionresnetv2']

pretrained_settings = {
    
    
    'inceptionresnetv2': {
    
    
        'imagenet': {
    
    
            'url': 'http://data.lip6.fr/cadene/pretrainedmodels/inceptionresnetv2-520b38e4.pth',
            'input_space': 'RGB',
            'input_size': [3, 299, 299],
            'input_range': [0, 1],
            'mean': [0.5, 0.5, 0.5],
            'std': [0.5, 0.5, 0.5],
            'num_classes': 1000
        },
        'imagenet+background': {
    
    
            'url': 'http://data.lip6.fr/cadene/pretrainedmodels/inceptionresnetv2-520b38e4.pth',
            'input_space': 'RGB',
            'input_size': [3, 299, 299],
            'input_range': [0, 1],
            'mean': [0.5, 0.5, 0.5],
            'std': [0.5, 0.5, 0.5],
            'num_classes': 1001
        }
    }
}


class BasicConv2d(nn.Module):

    def __init__(self, in_planes, out_planes, kernel_size, stride, padding=0):
        super(BasicConv2d, self).__init__()
        self.conv = nn.Conv2d(in_planes, out_planes,
                              kernel_size=kernel_size, stride=stride,
                              padding=padding, bias=False) # verify bias false
        self.bn = nn.BatchNorm2d(out_planes,
                                 eps=0.001, # value found in tensorflow
                                 momentum=0.1, # default pytorch value
                                 affine=True)
        self.relu = nn.ReLU(inplace=False)

    def forward(self, x):
        x = self.conv(x)
        x = self.bn(x)
        x = self.relu(x)
        return x


class Mixed_5b(nn.Module):

    def __init__(self):
        super(Mixed_5b, self).__init__()

        self.branch0 = BasicConv2d(192, 96, kernel_size=1, stride=1)

        self.branch1 = nn.Sequential(
            BasicConv2d(192, 48, kernel_size=1, stride=1),
            BasicConv2d(48, 64, kernel_size=5, stride=1, padding=2)
        )

        self.branch2 = nn.Sequential(
            BasicConv2d(192, 64, kernel_size=1, stride=1),
            BasicConv2d(64, 96, kernel_size=3, stride=1, padding=1),
            BasicConv2d(96, 96, kernel_size=3, stride=1, padding=1)
        )

        self.branch3 = nn.Sequential(
            nn.AvgPool2d(3, stride=1, padding=1, count_include_pad=False),
            BasicConv2d(192, 64, kernel_size=1, stride=1)
        )

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        x2 = self.branch2(x)
        x3 = self.branch3(x)
        out = torch.cat((x0, x1, x2, x3), 1)
        return out


class Block35(nn.Module):

    def __init__(self, scale=1.0):
        super(Block35, self).__init__()

        self.scale = scale

        self.branch0 = BasicConv2d(320, 32, kernel_size=1, stride=1)

        self.branch1 = nn.Sequential(
            BasicConv2d(320, 32, kernel_size=1, stride=1),
            BasicConv2d(32, 32, kernel_size=3, stride=1, padding=1)
        )

        self.branch2 = nn.Sequential(
            BasicConv2d(320, 32, kernel_size=1, stride=1),
            BasicConv2d(32, 48, kernel_size=3, stride=1, padding=1),
            BasicConv2d(48, 64, kernel_size=3, stride=1, padding=1)
        )

        self.conv2d = nn.Conv2d(128, 320, kernel_size=1, stride=1)
        self.relu = nn.ReLU(inplace=False)

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        x2 = self.branch2(x)
        out = torch.cat((x0, x1, x2), 1)
        out = self.conv2d(out)
        out = out * self.scale + x
        out = self.relu(out)
        return out


class Mixed_6a(nn.Module):

    def __init__(self):
        super(Mixed_6a, self).__init__()

        self.branch0 = BasicConv2d(320, 384, kernel_size=3, stride=2)

        self.branch1 = nn.Sequential(
            BasicConv2d(320, 256, kernel_size=1, stride=1),
            BasicConv2d(256, 256, kernel_size=3, stride=1, padding=1),
            BasicConv2d(256, 384, kernel_size=3, stride=2)
        )

        self.branch2 = nn.MaxPool2d(3, stride=2)

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        x2 = self.branch2(x)
        out = torch.cat((x0, x1, x2), 1)
        return out


class Block17(nn.Module):

    def __init__(self, scale=1.0):
        super(Block17, self).__init__()

        self.scale = scale

        self.branch0 = BasicConv2d(1088, 192, kernel_size=1, stride=1)

        self.branch1 = nn.Sequential(
            BasicConv2d(1088, 128, kernel_size=1, stride=1),
            BasicConv2d(128, 160, kernel_size=(1,7), stride=1, padding=(0,3)),
            BasicConv2d(160, 192, kernel_size=(7,1), stride=1, padding=(3,0))
        )

        self.conv2d = nn.Conv2d(384, 1088, kernel_size=1, stride=1)
        self.relu = nn.ReLU(inplace=False)

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        out = torch.cat((x0, x1), 1)
        out = self.conv2d(out)
        out = out * self.scale + x
        out = self.relu(out)
        return out


class Mixed_7a(nn.Module):

    def __init__(self):
        super(Mixed_7a, self).__init__()

        self.branch0 = nn.Sequential(
            BasicConv2d(1088, 256, kernel_size=1, stride=1),
            BasicConv2d(256, 384, kernel_size=3, stride=2)
        )

        self.branch1 = nn.Sequential(
            BasicConv2d(1088, 256, kernel_size=1, stride=1),
            BasicConv2d(256, 288, kernel_size=3, stride=2)
        )

        self.branch2 = nn.Sequential(
            BasicConv2d(1088, 256, kernel_size=1, stride=1),
            BasicConv2d(256, 288, kernel_size=3, stride=1, padding=1),
            BasicConv2d(288, 320, kernel_size=3, stride=2)
        )

        self.branch3 = nn.MaxPool2d(3, stride=2)

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        x2 = self.branch2(x)
        x3 = self.branch3(x)
        out = torch.cat((x0, x1, x2, x3), 1)
        return out


class Block8(nn.Module):

    def __init__(self, scale=1.0, noReLU=False):
        super(Block8, self).__init__()

        self.scale = scale
        self.noReLU = noReLU

        self.branch0 = BasicConv2d(2080, 192, kernel_size=1, stride=1)

        self.branch1 = nn.Sequential(
            BasicConv2d(2080, 192, kernel_size=1, stride=1),
            BasicConv2d(192, 224, kernel_size=(1,3), stride=1, padding=(0,1)),
            BasicConv2d(224, 256, kernel_size=(3,1), stride=1, padding=(1,0))
        )

        self.conv2d = nn.Conv2d(448, 2080, kernel_size=1, stride=1)
        if not self.noReLU:
            self.relu = nn.ReLU(inplace=False)

    def forward(self, x):
        x0 = self.branch0(x)
        x1 = self.branch1(x)
        out = torch.cat((x0, x1), 1)
        out = self.conv2d(out)
        out = out * self.scale + x
        if not self.noReLU:
            out = self.relu(out)
        return out


class InceptionResNetV2(nn.Module):

    def __init__(self, num_classes=1001):
        super(InceptionResNetV2, self).__init__()
        # Special attributs
        self.input_space = None
        self.input_size = (299, 299, 3)
        self.mean = None
        self.std = None
        # Modules
        self.conv2d_1a = BasicConv2d(3, 32, kernel_size=3, stride=2)
        self.conv2d_2a = BasicConv2d(32, 32, kernel_size=3, stride=1)
        self.conv2d_2b = BasicConv2d(32, 64, kernel_size=3, stride=1, padding=1)
        self.maxpool_3a = nn.MaxPool2d(3, stride=2)
        self.conv2d_3b = BasicConv2d(64, 80, kernel_size=1, stride=1)
        self.conv2d_4a = BasicConv2d(80, 192, kernel_size=3, stride=1)
        self.maxpool_5a = nn.MaxPool2d(3, stride=2)
        self.mixed_5b = Mixed_5b()
        self.repeat = nn.Sequential(
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17),
            Block35(scale=0.17)
        )
        self.mixed_6a = Mixed_6a()
        self.repeat_1 = nn.Sequential(
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10),
            Block17(scale=0.10)
        )
        self.mixed_7a = Mixed_7a()
        self.repeat_2 = nn.Sequential(
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20),
            Block8(scale=0.20)
        )
        self.block8 = Block8(noReLU=True)
        self.conv2d_7b = BasicConv2d(2080, 1536, kernel_size=1, stride=1)
        self.avgpool_1a = nn.AvgPool2d(8, count_include_pad=False)
        self.last_linear = nn.Linear(1536, num_classes)

    def features(self, input):
        x = self.conv2d_1a(input)
        x = self.conv2d_2a(x)
        x = self.conv2d_2b(x)
        x = self.maxpool_3a(x)
        x = self.conv2d_3b(x)
        x = self.conv2d_4a(x)
        x = self.maxpool_5a(x)
        x = self.mixed_5b(x)
        x = self.repeat(x)
        x = self.mixed_6a(x)
        x = self.repeat_1(x)
        x = self.mixed_7a(x)
        x = self.repeat_2(x)
        x = self.block8(x)
        x = self.conv2d_7b(x)
        return x

    def logits(self, features):
        x = self.avgpool_1a(features)
        x = x.view(x.size(0), -1)
        x = self.last_linear(x)
        return x

    def forward(self, input):
        x = self.features(input)
        x = self.logits(x)
        return x

def inceptionresnetv2(num_classes=1000, pretrained='imagenet'):
    r"""InceptionResNetV2 model architecture from the
    `"InceptionV4, Inception-ResNet..." <https://arxiv.org/abs/1602.07261>`_ paper.
    """
    if pretrained:
        settings = pretrained_settings['inceptionresnetv2'][pretrained]
        assert num_classes == settings['num_classes'], \
            "num_classes should be {}, but is {}".format(settings['num_classes'], num_classes)

        # both 'imagenet'&'imagenet+background' are loaded from same parameters
        model = InceptionResNetV2(num_classes=1001)
        model.load_state_dict(model_zoo.load_url(settings['url']))

        if pretrained == 'imagenet':
            new_last_linear = nn.Linear(1536, 1000)
            new_last_linear.weight.data = model.last_linear.weight.data[1:]
            new_last_linear.bias.data = model.last_linear.bias.data[1:]
            model.last_linear = new_last_linear

        model.input_space = settings['input_space']
        model.input_size = settings['input_size']
        model.input_range = settings['input_range']

        model.mean = settings['mean']
        model.std = settings['std']
    else:
        model = InceptionResNetV2(num_classes=num_classes)
    return model

#TEST
#Run this code with:

#cd $HOME/pretrained-models.pytorch
#python -m pretrainedmodels.inceptionresnetv2
if __name__ == '__main__':

    assert inceptionresnetv2(num_classes=10, pretrained=None)
    print('success')
    assert inceptionresnetv2(num_classes=1000, pretrained='imagenet')
    print('success')
    assert inceptionresnetv2(num_classes=1001, pretrained='imagenet+background')
    print('success')

    # fail
    assert inceptionresnetv2(num_classes=1001, pretrained='imagenet')

Inception ResNet V2 代码的通道数和类别数没有修改,有需要的可以自行修改,该论文出处为:
pretrained-models.pytorch

3 实验结果

在这里插入图片描述
网络训练速度加快!!

4 参考博客

GoogleNet论文研读及代码使用
Inception V4
InceptionV2-V3论文精读及代码

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转载自blog.csdn.net/qq_44864833/article/details/128935968
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