deeplab.py

import torch
import torch.nn as nn
import torch.nn.functional as F
from modeling.sync_batchnorm.batchnorm import SynchronizedBatchNorm2d
from modeling.aspp import build_aspp
from modeling.decoder import build_decoder
from modeling.backbone import build_backbone

class DeepLab(nn.Module):
    def __init__(self, backbone='resnet', output_stride=16, sync_bn=True, freeze_bn=False):
        super(DeepLab, self).__init__()
        if backbone == 'drn':
            output_stride = 8

        if sync_bn == True:
            BatchNorm = SynchronizedBatchNorm2d
        else:
            BatchNorm = nn.BatchNorm2d

        self.backbone = build_backbone(backbone, output_stride, BatchNorm)
        self.aspp = build_aspp(backbone, output_stride, BatchNorm)
        self.decoder = build_decoder(backbone, BatchNorm)

        self.freeze_bn = freeze_bn

    def forward(self, input):
        crop_h,crop_w = input.size(2),input.size(3)
        x, low_level_feat = self.backbone(input)
        x = self.aspp(x)  #([8, 256, 20, 20])
        x = self.decoder(x, low_level_feat,crop_h,crop_w)   #([8, 16, 80, 80])
        #x = F.interpolate(x, size=input.size()[2:], mode='bilinear', align_corners=True)
        return x

    def freeze_bn(self):
        for m in self.modules():
            if isinstance(m, SynchronizedBatchNorm2d):
                m.eval()
            elif isinstance(m, nn.BatchNorm2d):
                m.eval()

    def get_1x_lr_params(self):
        modules = [self.backbone]
        for i in range(len(modules)):
            for m in modules[i].named_modules():
                if self.freeze_bn:
                    if isinstance(m[1], nn.Conv2d):
                        for p in m[1].parameters():
                            if p.requires_grad:
                                yield p
                else:
                    if isinstance(m[1], nn.Conv2d) or isinstance(m[1], SynchronizedBatchNorm2d) \
                            or isinstance(m[1], nn.BatchNorm2d):
                        for p in m[1].parameters():
                            if p.requires_grad:
                                yield p

    def get_10x_lr_params(self):
        modules = [self.aspp, self.decoder]
        for i in range(len(modules)):
            for m in modules[i].named_modules():
                if self.freeze_bn:
                    if isinstance(m[1], nn.Conv2d):
                        for p in m[1].parameters():
                            if p.requires_grad:
                                yield p
                else:
                    if isinstance(m[1], nn.Conv2d) or isinstance(m[1], SynchronizedBatchNorm2d) \
                            or isinstance(m[1], nn.BatchNorm2d):
                        for p in m[1].parameters():
                            if p.requires_grad:
                                yield p

if __name__ == "__main__":
    model = DeepLab(backbone='resnet', output_stride=16)
    model.eval()
    input = torch.rand(1, 3, 513, 513)
    output = model(input)
    print(output.size())
    print(output)