DL-Art-School/codes/models/pixel_level_contrastive_learning/resnet_unet_3.py
James Betker 587a4f4050 resnet_unet_3
I'm being really lazy here - these nets are not really different from each other
except at which layer they terminate. This one terminates at 2x downsampling,
which is simply indicative of a direction I want to go for testing these pixpro networks.
2021-01-15 14:51:03 -07:00

87 lines
3.5 KiB
Python

import torch
import torch.nn as nn
from torchvision.models.resnet import BasicBlock, Bottleneck, conv1x1, conv3x3
from torchvision.models.utils import load_state_dict_from_url
import torchvision
from models.arch_util import ConvBnRelu
from models.pixel_level_contrastive_learning.resnet_unet import ReverseBottleneck
from trainer.networks import register_model
from utils.util import checkpoint, opt_get
class UResNet50_3(torchvision.models.resnet.ResNet):
def __init__(self, block, layers, num_classes=1000, zero_init_residual=False,
groups=1, width_per_group=64, replace_stride_with_dilation=None,
norm_layer=None, out_dim=128):
super().__init__(block, layers, num_classes, zero_init_residual, groups, width_per_group,
replace_stride_with_dilation, norm_layer)
if norm_layer is None:
norm_layer = nn.BatchNorm2d
'''
# For reference:
self.layer1 = self._make_layer(block, 64, layers[0])
self.layer2 = self._make_layer(block, 128, layers[1], stride=2,
dilate=replace_stride_with_dilation[0])
self.layer3 = self._make_layer(block, 256, layers[2], stride=2,
dilate=replace_stride_with_dilation[1])
self.layer4 = self._make_layer(block, 512, layers[3], stride=2,
dilate=replace_stride_with_dilation[2])
'''
uplayers = []
inplanes = 2048
first = True
for i in range(3):
uplayers.append(ReverseBottleneck(inplanes, inplanes // 2, norm_layer=norm_layer, passthrough=not first))
inplanes = inplanes // 2
first = False
self.uplayers = nn.ModuleList(uplayers)
# These two variables are separated out and renamed so that I can re-use parameters from a pretrained resnet_unet2.
self.last_uplayer = ReverseBottleneck(256, 128, norm_layer=norm_layer, passthrough=True)
self.tail3 = nn.Sequential(conv1x1(192, 128),
norm_layer(128),
nn.ReLU(),
conv1x1(128, out_dim))
del self.fc # Not used in this implementation and just consumes a ton of GPU memory.
def _forward_impl(self, x):
x0 = self.relu(self.bn1(self.conv1(x)))
x = self.maxpool(x0)
x1 = checkpoint(self.layer1, x)
x2 = checkpoint(self.layer2, x1)
x3 = checkpoint(self.layer3, x2)
x4 = checkpoint(self.layer4, x3)
unused = self.avgpool(x4) # This is performed for instance-level pixpro learning, even though it is unused.
x = checkpoint(self.uplayers[0], x4)
x = checkpoint(self.uplayers[1], x, x3)
x = checkpoint(self.uplayers[2], x, x2)
x = checkpoint(self.last_uplayer, x, x1)
return checkpoint(self.tail3, torch.cat([x, x0], dim=1))
def forward(self, x):
return self._forward_impl(x)
@register_model
def register_u_resnet50_3(opt_net, opt):
model = UResNet50_3(Bottleneck, [3, 4, 6, 3], out_dim=opt_net['odim'])
if opt_get(opt_net, ['use_pretrained_base'], False):
state_dict = load_state_dict_from_url('https://download.pytorch.org/models/resnet50-19c8e357.pth', progress=True)
model.load_state_dict(state_dict, strict=False)
return model
if __name__ == '__main__':
model = UResNet50_3(Bottleneck, [3,4,6,3])
samp = torch.rand(1,3,224,224)
y = model(samp)
print(y.shape)
# For pixpro: attach to "tail.3"