File size: 2,424 Bytes
2a41a22 d0e8e56 2a41a22 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 |
import torch
import torch.nn as nn
from collections import OrderedDict
from torchvision.models import vgg16, vgg16_bn, VGG16_Weights, VGG16_BN_Weights, resnet50, ResNet50_Weights
from models.pvt_v2 import pvt_v2_b0, pvt_v2_b1, pvt_v2_b2, pvt_v2_b5
from models.swin_v1 import swin_v1_t, swin_v1_s, swin_v1_b, swin_v1_l
from config import Config
config = Config()
def build_backbone(bb_name, pretrained=True, params_settings=''):
if bb_name == 'vgg16':
bb_net = list(vgg16(pretrained=VGG16_Weights.DEFAULT if pretrained else None).children())[0]
bb = nn.Sequential(OrderedDict({'conv1': bb_net[:4], 'conv2': bb_net[4:9], 'conv3': bb_net[9:16], 'conv4': bb_net[16:23]}))
elif bb_name == 'vgg16bn':
bb_net = list(vgg16_bn(pretrained=VGG16_BN_Weights.DEFAULT if pretrained else None).children())[0]
bb = nn.Sequential(OrderedDict({'conv1': bb_net[:6], 'conv2': bb_net[6:13], 'conv3': bb_net[13:23], 'conv4': bb_net[23:33]}))
elif bb_name == 'resnet50':
bb_net = list(resnet50(pretrained=ResNet50_Weights.DEFAULT if pretrained else None).children())
bb = nn.Sequential(OrderedDict({'conv1': nn.Sequential(*bb_net[0:3]), 'conv2': bb_net[4], 'conv3': bb_net[5], 'conv4': bb_net[6]}))
else:
bb = eval('{}({})'.format(bb_name, params_settings))
if pretrained:
bb = load_weights(bb, bb_name)
return bb
def load_weights(model, model_name):
save_model = torch.load(config.weights[model_name], map_location='cpu')
model_dict = model.state_dict()
state_dict = {k: v if v.size() == model_dict[k].size() else model_dict[k] for k, v in save_model.items() if k in model_dict.keys()}
# to ignore the weights with mismatched size when I modify the backbone itself.
if not state_dict:
save_model_keys = list(save_model.keys())
sub_item = save_model_keys[0] if len(save_model_keys) == 1 else None
state_dict = {k: v if v.size() == model_dict[k].size() else model_dict[k] for k, v in save_model[sub_item].items() if k in model_dict.keys()}
if not state_dict or not sub_item:
print('Weights are not successully loaded. Check the state dict of weights file.')
return None
else:
print('Found correct weights in the "{}" item of loaded state_dict.'.format(sub_item))
model_dict.update(state_dict)
model.load_state_dict(model_dict)
return model
|