Files
DAPT/deepcore/nets/wideresnet.py
2025-10-07 22:42:55 +08:00

182 lines
8.1 KiB
Python

import torch
import torch.nn as nn
import torch.nn.functional as F
from .nets_utils import EmbeddingRecorder
from torchvision.models import resnet
from .resnet import ResNet_224x224
# Acknowledgement to
# https://github.com/xternalz/WideResNet-pytorch
class BasicBlock(nn.Module):
def __init__(self, in_planes, out_planes, stride, dropRate=0.0):
super(BasicBlock, self).__init__()
self.bn1 = nn.BatchNorm2d(in_planes)
self.relu1 = nn.ReLU(inplace=True)
self.conv1 = nn.Conv2d(in_planes, out_planes, kernel_size=3, stride=stride,
padding=1, bias=False)
self.bn2 = nn.BatchNorm2d(out_planes)
self.relu2 = nn.ReLU(inplace=True)
self.conv2 = nn.Conv2d(out_planes, out_planes, kernel_size=3, stride=1,
padding=1, bias=False)
self.droprate = dropRate
self.equalInOut = (in_planes == out_planes)
self.convShortcut = (not self.equalInOut) and nn.Conv2d(in_planes, out_planes, kernel_size=1, stride=stride,
padding=0, bias=False) or None
def forward(self, x):
if not self.equalInOut:
x = self.relu1(self.bn1(x))
else:
out = self.relu1(self.bn1(x))
out = self.relu2(self.bn2(self.conv1(out if self.equalInOut else x)))
if self.droprate > 0:
out = F.dropout(out, p=self.droprate, training=self.training)
out = self.conv2(out)
return torch.add(x if self.equalInOut else self.convShortcut(x), out)
class NetworkBlock(nn.Module):
def __init__(self, nb_layers, in_planes, out_planes, block, stride, dropRate=0.0):
super(NetworkBlock, self).__init__()
self.layer = self._make_layer(block, in_planes, out_planes, nb_layers, stride, dropRate)
def _make_layer(self, block, in_planes, out_planes, nb_layers, stride, dropRate):
layers = []
for i in range(int(nb_layers)):
layers.append(block(i == 0 and in_planes or out_planes, out_planes, i == 0 and stride or 1, dropRate))
return nn.Sequential(*layers)
def forward(self, x):
return self.layer(x)
class WideResNet_32x32(nn.Module):
def __init__(self, depth, num_classes, channel=3, widen_factor=1, drop_rate=0.0, record_embedding=False,
no_grad=False):
super(WideResNet_32x32, self).__init__()
nChannels = [16, 16 * widen_factor, 32 * widen_factor, 64 * widen_factor]
assert ((depth - 4) % 6 == 0)
n = (depth - 4) / 6
block = BasicBlock
# 1st conv before any network block
self.conv1 = nn.Conv2d(channel, nChannels[0], kernel_size=3, stride=1,
padding=3 if channel == 1 else 1, bias=False)
# 1st block
self.block1 = NetworkBlock(n, nChannels[0], nChannels[1], block, 1, drop_rate)
# 2nd block
self.block2 = NetworkBlock(n, nChannels[1], nChannels[2], block, 2, drop_rate)
# 3rd block
self.block3 = NetworkBlock(n, nChannels[2], nChannels[3], block, 2, drop_rate)
# global average pooling and classifier
self.bn1 = nn.BatchNorm2d(nChannels[3])
self.relu = nn.ReLU(inplace=True)
self.fc = nn.Linear(nChannels[3], num_classes)
self.nChannels = nChannels[3]
for m in self.modules():
if isinstance(m, nn.Conv2d):
nn.init.kaiming_normal_(m.weight, mode='fan_out', nonlinearity='relu')
elif isinstance(m, nn.BatchNorm2d):
m.weight.data.fill_(1)
m.bias.data.zero_()
elif isinstance(m, nn.Linear):
m.bias.data.zero_()
self.embedding_recorder = EmbeddingRecorder(record_embedding)
self.no_grad = no_grad
def get_last_layer(self):
return self.fc
def forward(self, x):
with torch.set_grad_enabled(not self.no_grad):
out = self.conv1(x)
out = self.block1(out)
out = self.block2(out)
out = self.block3(out)
out = self.relu(self.bn1(out))
out = F.avg_pool2d(out, 8)
out = out.view(-1, self.nChannels)
out = self.embedding_recorder(out)
return self.fc(out)
def WideResNet(arch: str, channel: int, num_classes: int, im_size, record_embedding: bool = False,
no_grad: bool = False, pretrained: bool = False):
arch = arch.lower()
if pretrained:
if im_size[0] != 224 or im_size[1] != 224:
raise NotImplementedError("torchvison pretrained models only accept inputs with size of 224*224")
if arch == "wrn502":
arch = "wide_resnet50_2"
net = ResNet_224x224(resnet.Bottleneck, [3, 4, 6, 3], channel=3, num_classes=1000,
record_embedding=record_embedding, no_grad=no_grad, width_per_group=64 * 2)
elif arch == "wrn1012":
arch = "wide_resnet101_2"
net = ResNet_224x224(resnet.Bottleneck, [3, 4, 23, 3], channel=3, num_classes=1000,
record_embedding=record_embedding, no_grad=no_grad, width_per_group=64 * 2)
else:
raise ValueError("Model architecture not found.")
from torch.hub import load_state_dict_from_url
state_dict = load_state_dict_from_url(resnet.model_urls[arch], progress=True)
net.load_state_dict(state_dict)
if channel != 3:
net.conv1 = nn.Conv2d(channel, 64, kernel_size=7, stride=2, padding=3, bias=False)
if num_classes != 1000:
net.fc = nn.Linear(net.fc.in_features, num_classes)
elif im_size[0] == 224 and im_size[1] == 224:
# Use torchvision models without pretrained parameters
if arch == "wrn502":
arch = "wide_resnet50_2"
net = ResNet_224x224(resnet.Bottleneck, [3, 4, 6, 3], channel=channel, num_classes=num_classes,
record_embedding=record_embedding, no_grad=no_grad, width_per_group=64 * 2)
elif arch == "wrn1012":
arch = "wide_resnet101_2"
net = ResNet_224x224(resnet.Bottleneck, [3, 4, 23, 3], channel=channel, num_classes=num_classes,
record_embedding=record_embedding, no_grad=no_grad, width_per_group=64 * 2)
else:
raise ValueError("Model architecture not found.")
elif (channel == 1 and im_size[0] == 28 and im_size[1] == 28) or (
channel == 3 and im_size[0] == 32 and im_size[1] == 32):
if arch == "wrn168":
net = WideResNet_32x32(16, num_classes, channel, 8)
elif arch == "wrn2810":
net = WideResNet_32x32(28, num_classes, channel, 10)
elif arch == "wrn282":
net = WideResNet_32x32(28, num_classes, channel, 2)
else:
raise ValueError("Model architecture not found.")
else:
raise NotImplementedError("Network Architecture for current dataset has not been implemented.")
return net
def WRN168(channel: int, num_classes: int, im_size, record_embedding: bool = False, no_grad: bool = False,
pretrained: bool = False):
return WideResNet("wrn168", channel, num_classes, im_size, record_embedding, no_grad, pretrained)
def WRN2810(channel: int, num_classes: int, im_size, record_embedding: bool = False, no_grad: bool = False,
pretrained: bool = False):
return WideResNet("wrn2810", channel, num_classes, im_size, record_embedding, no_grad, pretrained)
def WRN282(channel: int, num_classes: int, im_size, record_embedding: bool = False, no_grad: bool = False,
pretrained: bool = False):
return WideResNet('wrn282', channel, num_classes, im_size, record_embedding, no_grad, pretrained)
def WRN502(channel: int, num_classes: int, im_size, record_embedding: bool = False, no_grad: bool = False,
pretrained: bool = False):
return WideResNet("wrn502", channel, num_classes, im_size, record_embedding, no_grad, pretrained)
def WRN1012(channel: int, num_classes: int, im_size, record_embedding: bool = False, no_grad: bool = False,
pretrained: bool = False):
return WideResNet("wrn1012", channel, num_classes, im_size, record_embedding, no_grad, pretrained)