| import torch | |
| import torch.nn as nn | |
| import torch.nn.functional as F | |
| from .common import Activation | |
| class ConvBNLayer(nn.Module): | |
| def __init__( | |
| self, num_channels, filter_size, num_filters, stride, padding, channels=None, num_groups=1, act="hard_swish" | |
| ): | |
| super(ConvBNLayer, self).__init__() | |
| self.act = act | |
| self._conv = nn.Conv2d( | |
| in_channels=num_channels, | |
| out_channels=num_filters, | |
| kernel_size=filter_size, | |
| stride=stride, | |
| padding=padding, | |
| groups=num_groups, | |
| bias=False, | |
| ) | |
| self._batch_norm = nn.BatchNorm2d( | |
| num_filters, | |
| ) | |
| if self.act is not None: | |
| self._act = Activation(act_type=act, inplace=True) | |
| def forward(self, inputs): | |
| y = self._conv(inputs) | |
| y = self._batch_norm(y) | |
| if self.act is not None: | |
| y = self._act(y) | |
| return y | |
| class DepthwiseSeparable(nn.Module): | |
| def __init__( | |
| self, num_channels, num_filters1, num_filters2, num_groups, stride, scale, dw_size=3, padding=1, use_se=False | |
| ): | |
| super(DepthwiseSeparable, self).__init__() | |
| self.use_se = use_se | |
| self._depthwise_conv = ConvBNLayer( | |
| num_channels=num_channels, | |
| num_filters=int(num_filters1 * scale), | |
| filter_size=dw_size, | |
| stride=stride, | |
| padding=padding, | |
| num_groups=int(num_groups * scale), | |
| ) | |
| if use_se: | |
| self._se = SEModule(int(num_filters1 * scale)) | |
| self._pointwise_conv = ConvBNLayer( | |
| num_channels=int(num_filters1 * scale), | |
| filter_size=1, | |
| num_filters=int(num_filters2 * scale), | |
| stride=1, | |
| padding=0, | |
| ) | |
| def forward(self, inputs): | |
| y = self._depthwise_conv(inputs) | |
| if self.use_se: | |
| y = self._se(y) | |
| y = self._pointwise_conv(y) | |
| return y | |
| class MobileNetV1Enhance(nn.Module): | |
| def __init__(self, in_channels=3, scale=0.5, last_conv_stride=1, last_pool_type="max", **kwargs): | |
| super().__init__() | |
| self.scale = scale | |
| self.block_list = [] | |
| self.conv1 = ConvBNLayer( | |
| num_channels=in_channels, filter_size=3, channels=3, num_filters=int(32 * scale), stride=2, padding=1 | |
| ) | |
| conv2_1 = DepthwiseSeparable( | |
| num_channels=int(32 * scale), num_filters1=32, num_filters2=64, num_groups=32, stride=1, scale=scale | |
| ) | |
| self.block_list.append(conv2_1) | |
| conv2_2 = DepthwiseSeparable( | |
| num_channels=int(64 * scale), num_filters1=64, num_filters2=128, num_groups=64, stride=1, scale=scale | |
| ) | |
| self.block_list.append(conv2_2) | |
| conv3_1 = DepthwiseSeparable( | |
| num_channels=int(128 * scale), num_filters1=128, num_filters2=128, num_groups=128, stride=1, scale=scale | |
| ) | |
| self.block_list.append(conv3_1) | |
| conv3_2 = DepthwiseSeparable( | |
| num_channels=int(128 * scale), | |
| num_filters1=128, | |
| num_filters2=256, | |
| num_groups=128, | |
| stride=(2, 1), | |
| scale=scale, | |
| ) | |
| self.block_list.append(conv3_2) | |
| conv4_1 = DepthwiseSeparable( | |
| num_channels=int(256 * scale), num_filters1=256, num_filters2=256, num_groups=256, stride=1, scale=scale | |
| ) | |
| self.block_list.append(conv4_1) | |
| conv4_2 = DepthwiseSeparable( | |
| num_channels=int(256 * scale), | |
| num_filters1=256, | |
| num_filters2=512, | |
| num_groups=256, | |
| stride=(2, 1), | |
| scale=scale, | |
| ) | |
| self.block_list.append(conv4_2) | |
| for _ in range(5): | |
| conv5 = DepthwiseSeparable( | |
| num_channels=int(512 * scale), | |
| num_filters1=512, | |
| num_filters2=512, | |
| num_groups=512, | |
| stride=1, | |
| dw_size=5, | |
| padding=2, | |
| scale=scale, | |
| use_se=False, | |
| ) | |
| self.block_list.append(conv5) | |
| conv5_6 = DepthwiseSeparable( | |
| num_channels=int(512 * scale), | |
| num_filters1=512, | |
| num_filters2=1024, | |
| num_groups=512, | |
| stride=(2, 1), | |
| dw_size=5, | |
| padding=2, | |
| scale=scale, | |
| use_se=True, | |
| ) | |
| self.block_list.append(conv5_6) | |
| conv6 = DepthwiseSeparable( | |
| num_channels=int(1024 * scale), | |
| num_filters1=1024, | |
| num_filters2=1024, | |
| num_groups=1024, | |
| stride=last_conv_stride, | |
| dw_size=5, | |
| padding=2, | |
| use_se=True, | |
| scale=scale, | |
| ) | |
| self.block_list.append(conv6) | |
| self.block_list = nn.Sequential(*self.block_list) | |
| if last_pool_type == "avg": | |
| self.pool = nn.AvgPool2d(kernel_size=2, stride=2, padding=0) | |
| else: | |
| self.pool = nn.MaxPool2d(kernel_size=2, stride=2, padding=0) | |
| self.out_channels = int(1024 * scale) | |
| def forward(self, inputs): | |
| y = self.conv1(inputs) | |
| y = self.block_list(y) | |
| y = self.pool(y) | |
| return y | |
| def hardsigmoid(x): | |
| return F.relu6(x + 3.0, inplace=True) / 6.0 | |
| class SEModule(nn.Module): | |
| def __init__(self, channel, reduction=4): | |
| super(SEModule, self).__init__() | |
| self.avg_pool = nn.AdaptiveAvgPool2d(1) | |
| self.conv1 = nn.Conv2d( | |
| in_channels=channel, out_channels=channel // reduction, kernel_size=1, stride=1, padding=0, bias=True | |
| ) | |
| self.conv2 = nn.Conv2d( | |
| in_channels=channel // reduction, out_channels=channel, kernel_size=1, stride=1, padding=0, bias=True | |
| ) | |
| def forward(self, inputs): | |
| outputs = self.avg_pool(inputs) | |
| outputs = self.conv1(outputs) | |
| outputs = F.relu(outputs) | |
| outputs = self.conv2(outputs) | |
| outputs = hardsigmoid(outputs) | |
| x = torch.mul(inputs, outputs) | |
| return x | |