AIlib2/segutils/core/models/fcnv2.py

83 lines
2.8 KiB
Python

"""Fully Convolutional Network with Stride of 8"""
from __future__ import division
import torch
import torch.nn as nn
import torch.nn.functional as F
from .segbase import SegBaseModel
__all__ = ['FCN', 'get_fcn', 'get_fcn_resnet50_voc',
'get_fcn_resnet101_voc', 'get_fcn_resnet152_voc']
class FCN(SegBaseModel):
def __init__(self, nclass, backbone='resnet50', aux=True, pretrained_base=True, **kwargs):
super(FCN, self).__init__(nclass, aux, backbone, pretrained_base=pretrained_base, **kwargs)
self.head = _FCNHead(2048, nclass, **kwargs)
if aux:
self.auxlayer = _FCNHead(1024, nclass, **kwargs)
self.__setattr__('exclusive', ['head', 'auxlayer'] if aux else ['head'])
def forward(self, x):
size = x.size()[2:]
_, _, c3, c4 = self.base_forward(x)
outputs = []
x = self.head(c4)
x = F.interpolate(x, size, mode='bilinear', align_corners=True)
outputs.append(x)
if self.aux:
auxout = self.auxlayer(c3)
auxout = F.interpolate(auxout, size, mode='bilinear', align_corners=True)
outputs.append(auxout)
return tuple(outputs)
class _FCNHead(nn.Module):
def __init__(self, in_channels, channels, norm_layer=nn.BatchNorm2d, norm_kwargs=None, **kwargs):
super(_FCNHead, self).__init__()
inter_channels = in_channels // 4
self.block = nn.Sequential(
nn.Conv2d(in_channels, inter_channels, 3, padding=1, bias=False),
norm_layer(inter_channels, **({} if norm_kwargs is None else norm_kwargs)),
nn.ReLU(True),
nn.Dropout(0.1),
nn.Conv2d(inter_channels, channels, 1)
)
def forward(self, x):
return self.block(x)
def get_fcn(dataset='pascal_voc', backbone='resnet50', pretrained=False, root='~/.torch/models',
pretrained_base=True, **kwargs):
acronyms = {
'pascal_voc': 'pascal_voc',
'pascal_aug': 'pascal_aug',
'ade20k': 'ade',
'coco': 'coco',
'citys': 'citys',
}
from ..data.dataloader import datasets
model = FCN(datasets[dataset].NUM_CLASS, backbone=backbone, pretrained_base=pretrained_base, **kwargs)
if pretrained:
from .model_store import get_model_file
device = torch.device(kwargs['local_rank'])
model.load_state_dict(torch.load(get_model_file('fcn_%s_%s' % (backbone, acronyms[dataset]), root=root),
map_location=device))
return model
def get_fcn_resnet50_voc(**kwargs):
return get_fcn('pascal_voc', 'resnet50', **kwargs)
def get_fcn_resnet101_voc(**kwargs):
return get_fcn('pascal_voc', 'resnet101', **kwargs)
def get_fcn_resnet152_voc(**kwargs):
return get_fcn('pascal_voc', 'resnet152', **kwargs)