| import math |
| import torch |
| import torch.nn as nn |
| import torch.nn.functional as F |
| import torch.utils.model_zoo as model_zoo |
| from modeling.sync_batchnorm.batchnorm import SynchronizedBatchNorm2d |
|
|
| def fixed_padding(inputs, kernel_size, dilation): |
| kernel_size_effective = kernel_size + (kernel_size - 1) * (dilation - 1) |
| pad_total = kernel_size_effective - 1 |
| pad_beg = pad_total // 2 |
| pad_end = pad_total - pad_beg |
| padded_inputs = F.pad(inputs, (pad_beg, pad_end, pad_beg, pad_end)) |
| return padded_inputs |
|
|
|
|
| class SeparableConv2d(nn.Module): |
| def __init__(self, inplanes, planes, kernel_size=3, stride=1, dilation=1, bias=False, BatchNorm=None): |
| super(SeparableConv2d, self).__init__() |
|
|
| self.conv1 = nn.Conv2d(inplanes, inplanes, kernel_size, stride, 0, dilation, |
| groups=inplanes, bias=bias) |
| self.bn = BatchNorm(inplanes) |
| self.pointwise = nn.Conv2d(inplanes, planes, 1, 1, 0, 1, 1, bias=bias) |
|
|
| def forward(self, x): |
| x = fixed_padding(x, self.conv1.kernel_size[0], dilation=self.conv1.dilation[0]) |
| x = self.conv1(x) |
| x = self.bn(x) |
| x = self.pointwise(x) |
| return x |
|
|
|
|
| class Block(nn.Module): |
| def __init__(self, inplanes, planes, reps, stride=1, dilation=1, BatchNorm=None, |
| start_with_relu=True, grow_first=True, is_last=False): |
| super(Block, self).__init__() |
|
|
| if planes != inplanes or stride != 1: |
| self.skip = nn.Conv2d(inplanes, planes, 1, stride=stride, bias=False) |
| self.skipbn = BatchNorm(planes) |
| else: |
| self.skip = None |
|
|
| self.relu = nn.ReLU(inplace=True) |
| rep = [] |
|
|
| filters = inplanes |
| if grow_first: |
| rep.append(self.relu) |
| rep.append(SeparableConv2d(inplanes, planes, 3, 1, dilation, BatchNorm=BatchNorm)) |
| rep.append(BatchNorm(planes)) |
| filters = planes |
|
|
| for i in range(reps - 1): |
| rep.append(self.relu) |
| rep.append(SeparableConv2d(filters, filters, 3, 1, dilation, BatchNorm=BatchNorm)) |
| rep.append(BatchNorm(filters)) |
|
|
| if not grow_first: |
| rep.append(self.relu) |
| rep.append(SeparableConv2d(inplanes, planes, 3, 1, dilation, BatchNorm=BatchNorm)) |
| rep.append(BatchNorm(planes)) |
|
|
| if stride != 1: |
| rep.append(self.relu) |
| rep.append(SeparableConv2d(planes, planes, 3, 2, BatchNorm=BatchNorm)) |
| rep.append(BatchNorm(planes)) |
|
|
| if stride == 1 and is_last: |
| rep.append(self.relu) |
| rep.append(SeparableConv2d(planes, planes, 3, 1, BatchNorm=BatchNorm)) |
| rep.append(BatchNorm(planes)) |
|
|
| if not start_with_relu: |
| rep = rep[1:] |
|
|
| self.rep = nn.Sequential(*rep) |
|
|
| def forward(self, inp): |
| x = self.rep(inp) |
|
|
| if self.skip is not None: |
| skip = self.skip(inp) |
| skip = self.skipbn(skip) |
| else: |
| skip = inp |
|
|
| x = x + skip |
|
|
| return x |
|
|
|
|
| class AlignedXception(nn.Module): |
| """ |
| Modified Alighed Xception |
| """ |
| def __init__(self, output_stride, BatchNorm, |
| pretrained=True): |
| super(AlignedXception, self).__init__() |
|
|
| if output_stride == 16: |
| entry_block3_stride = 2 |
| middle_block_dilation = 1 |
| exit_block_dilations = (1, 2) |
| elif output_stride == 8: |
| entry_block3_stride = 1 |
| middle_block_dilation = 2 |
| exit_block_dilations = (2, 4) |
| else: |
| raise NotImplementedError |
|
|
|
|
| |
| self.conv1 = nn.Conv2d(3, 32, 3, stride=2, padding=1, bias=False) |
| self.bn1 = BatchNorm(32) |
| self.relu = nn.ReLU(inplace=True) |
|
|
| self.conv2 = nn.Conv2d(32, 64, 3, stride=1, padding=1, bias=False) |
| self.bn2 = BatchNorm(64) |
|
|
| self.block1 = Block(64, 128, reps=2, stride=2, BatchNorm=BatchNorm, start_with_relu=False) |
| self.block2 = Block(128, 256, reps=2, stride=2, BatchNorm=BatchNorm, start_with_relu=False, |
| grow_first=True) |
| self.block3 = Block(256, 728, reps=2, stride=entry_block3_stride, BatchNorm=BatchNorm, |
| start_with_relu=True, grow_first=True, is_last=True) |
|
|
| |
| self.block4 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block5 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block6 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block7 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block8 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block9 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block10 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block11 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block12 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block13 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block14 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block15 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block16 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block17 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block18 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
| self.block19 = Block(728, 728, reps=3, stride=1, dilation=middle_block_dilation, |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=True) |
|
|
| |
| self.block20 = Block(728, 1024, reps=2, stride=1, dilation=exit_block_dilations[0], |
| BatchNorm=BatchNorm, start_with_relu=True, grow_first=False, is_last=True) |
|
|
| self.conv3 = SeparableConv2d(1024, 1536, 3, stride=1, dilation=exit_block_dilations[1], BatchNorm=BatchNorm) |
| self.bn3 = BatchNorm(1536) |
|
|
| self.conv4 = SeparableConv2d(1536, 1536, 3, stride=1, dilation=exit_block_dilations[1], BatchNorm=BatchNorm) |
| self.bn4 = BatchNorm(1536) |
|
|
| self.conv5 = SeparableConv2d(1536, 2048, 3, stride=1, dilation=exit_block_dilations[1], BatchNorm=BatchNorm) |
| self.bn5 = BatchNorm(2048) |
|
|
| |
| self._init_weight() |
|
|
| |
| if pretrained: |
| self._load_pretrained_model() |
|
|
| def forward(self, x): |
| |
| x = self.conv1(x) |
| x = self.bn1(x) |
| x = self.relu(x) |
|
|
| x = self.conv2(x) |
| x = self.bn2(x) |
| x = self.relu(x) |
|
|
| x = self.block1(x) |
| |
| x = self.relu(x) |
| low_level_feat = x |
| x = self.block2(x) |
| x = self.block3(x) |
|
|
| |
| x = self.block4(x) |
| x = self.block5(x) |
| x = self.block6(x) |
| x = self.block7(x) |
| x = self.block8(x) |
| x = self.block9(x) |
| x = self.block10(x) |
| x = self.block11(x) |
| x = self.block12(x) |
| x = self.block13(x) |
| x = self.block14(x) |
| x = self.block15(x) |
| x = self.block16(x) |
| x = self.block17(x) |
| x = self.block18(x) |
| x = self.block19(x) |
|
|
| |
| x = self.block20(x) |
| x = self.relu(x) |
| x = self.conv3(x) |
| x = self.bn3(x) |
| x = self.relu(x) |
|
|
| x = self.conv4(x) |
| x = self.bn4(x) |
| x = self.relu(x) |
|
|
| x = self.conv5(x) |
| x = self.bn5(x) |
| x = self.relu(x) |
|
|
| return x, low_level_feat |
|
|
| def _init_weight(self): |
| for m in self.modules(): |
| if isinstance(m, nn.Conv2d): |
| n = m.kernel_size[0] * m.kernel_size[1] * m.out_channels |
| m.weight.data.normal_(0, math.sqrt(2. / n)) |
| elif isinstance(m, SynchronizedBatchNorm2d): |
| m.weight.data.fill_(1) |
| m.bias.data.zero_() |
| elif isinstance(m, nn.BatchNorm2d): |
| m.weight.data.fill_(1) |
| m.bias.data.zero_() |
|
|
|
|
| def _load_pretrained_model(self): |
| pretrain_dict = model_zoo.load_url('http://data.lip6.fr/cadene/pretrainedmodels/xception-b5690688.pth') |
| model_dict = {} |
| state_dict = self.state_dict() |
|
|
| for k, v in pretrain_dict.items(): |
| if k in state_dict: |
| if 'pointwise' in k: |
| v = v.unsqueeze(-1).unsqueeze(-1) |
| if k.startswith('block11'): |
| model_dict[k] = v |
| model_dict[k.replace('block11', 'block12')] = v |
| model_dict[k.replace('block11', 'block13')] = v |
| model_dict[k.replace('block11', 'block14')] = v |
| model_dict[k.replace('block11', 'block15')] = v |
| model_dict[k.replace('block11', 'block16')] = v |
| model_dict[k.replace('block11', 'block17')] = v |
| model_dict[k.replace('block11', 'block18')] = v |
| model_dict[k.replace('block11', 'block19')] = v |
| elif k.startswith('block12'): |
| model_dict[k.replace('block12', 'block20')] = v |
| elif k.startswith('bn3'): |
| model_dict[k] = v |
| model_dict[k.replace('bn3', 'bn4')] = v |
| elif k.startswith('conv4'): |
| model_dict[k.replace('conv4', 'conv5')] = v |
| elif k.startswith('bn4'): |
| model_dict[k.replace('bn4', 'bn5')] = v |
| else: |
| model_dict[k] = v |
| state_dict.update(model_dict) |
| self.load_state_dict(state_dict) |
|
|
|
|
|
|
| if __name__ == "__main__": |
| import torch |
| model = AlignedXception(BatchNorm=nn.BatchNorm2d, pretrained=True, output_stride=16) |
| input = torch.rand(1, 3, 512, 512) |
| output, low_level_feat = model(input) |
| print(output.size()) |
| print(low_level_feat.size()) |
|
|