import torch import torch.nn as nn import torch.nn.functional as F def conv_bn(inp, oup, stride=1, leaky=0): return nn.Sequential( nn.Conv2d(inp, oup, 3, stride, 1, bias=False), nn.BatchNorm2d(oup), nn.LeakyReLU(negative_slope=leaky, inplace=True)) def conv_bn_no_relu(inp, oup, stride): return nn.Sequential( nn.Conv2d(inp, oup, 3, stride, 1, bias=False), nn.BatchNorm2d(oup), ) def conv_bn1X1(inp, oup, stride, leaky=0): return nn.Sequential( nn.Conv2d(inp, oup, 1, stride, padding=0, bias=False), nn.BatchNorm2d(oup), nn.LeakyReLU(negative_slope=leaky, inplace=True)) def conv_dw(inp, oup, stride, leaky=0.1): return nn.Sequential( nn.Conv2d(inp, inp, 3, stride, 1, groups=inp, bias=False), nn.BatchNorm2d(inp), nn.LeakyReLU(negative_slope=leaky, inplace=True), nn.Conv2d(inp, oup, 1, 1, 0, bias=False), nn.BatchNorm2d(oup), nn.LeakyReLU(negative_slope=leaky, inplace=True), ) class SSH(nn.Module): def __init__(self, in_channel, out_channel): super(SSH, self).__init__() assert out_channel % 4 == 0 leaky = 0 if (out_channel <= 64): leaky = 0.1 self.conv3X3 = conv_bn_no_relu(in_channel, out_channel // 2, stride=1) self.conv5X5_1 = conv_bn(in_channel, out_channel // 4, stride=1, leaky=leaky) self.conv5X5_2 = conv_bn_no_relu(out_channel // 4, out_channel // 4, stride=1) self.conv7X7_2 = conv_bn(out_channel // 4, out_channel // 4, stride=1, leaky=leaky) self.conv7x7_3 = conv_bn_no_relu(out_channel // 4, out_channel // 4, stride=1) def forward(self, input): conv3X3 = self.conv3X3(input) conv5X5_1 = self.conv5X5_1(input) conv5X5 = self.conv5X5_2(conv5X5_1) conv7X7_2 = self.conv7X7_2(conv5X5_1) conv7X7 = self.conv7x7_3(conv7X7_2) out = torch.cat([conv3X3, conv5X5, conv7X7], dim=1) out = F.relu(out) return out class FPN(nn.Module): def __init__(self, in_channels_list, out_channels): super(FPN, self).__init__() leaky = 0 if (out_channels <= 64): leaky = 0.1 self.output1 = conv_bn1X1(in_channels_list[0], out_channels, stride=1, leaky=leaky) self.output2 = conv_bn1X1(in_channels_list[1], out_channels, stride=1, leaky=leaky) self.output3 = conv_bn1X1(in_channels_list[2], out_channels, stride=1, leaky=leaky) self.merge1 = conv_bn(out_channels, out_channels, leaky=leaky) self.merge2 = conv_bn(out_channels, out_channels, leaky=leaky) def forward(self, input): # names = list(input.keys()) # input = list(input.values()) output1 = self.output1(input[0]) output2 = self.output2(input[1]) output3 = self.output3(input[2]) up3 = F.interpolate(output3, size=[output2.size(2), output2.size(3)], mode='nearest') output2 = output2 + up3 output2 = self.merge2(output2) up2 = F.interpolate(output2, size=[output1.size(2), output1.size(3)], mode='nearest') output1 = output1 + up2 output1 = self.merge1(output1) out = [output1, output2, output3] return out class MobileNetV1(nn.Module): def __init__(self): super(MobileNetV1, self).__init__() self.stage1 = nn.Sequential( conv_bn(3, 8, 2, leaky=0.1), # 3 conv_dw(8, 16, 1), # 7 conv_dw(16, 32, 2), # 11 conv_dw(32, 32, 1), # 19 conv_dw(32, 64, 2), # 27 conv_dw(64, 64, 1), # 43 ) self.stage2 = nn.Sequential( conv_dw(64, 128, 2), # 43 + 16 = 59 conv_dw(128, 128, 1), # 59 + 32 = 91 conv_dw(128, 128, 1), # 91 + 32 = 123 conv_dw(128, 128, 1), # 123 + 32 = 155 conv_dw(128, 128, 1), # 155 + 32 = 187 conv_dw(128, 128, 1), # 187 + 32 = 219 ) self.stage3 = nn.Sequential( conv_dw(128, 256, 2), # 219 +3 2 = 241 conv_dw(256, 256, 1), # 241 + 64 = 301 ) self.avg = nn.AdaptiveAvgPool2d((1, 1)) self.fc = nn.Linear(256, 1000) def forward(self, x): x = self.stage1(x) x = self.stage2(x) x = self.stage3(x) x = self.avg(x) # x = self.model(x) x = x.view(-1, 256) x = self.fc(x) return x class ClassHead(nn.Module): def __init__(self, inchannels=512, num_anchors=3): super(ClassHead, self).__init__() self.num_anchors = num_anchors self.conv1x1 = nn.Conv2d(inchannels, self.num_anchors * 2, kernel_size=(1, 1), stride=1, padding=0) def forward(self, x): out = self.conv1x1(x) out = out.permute(0, 2, 3, 1).contiguous() return out.view(out.shape[0], -1, 2) class BboxHead(nn.Module): def __init__(self, inchannels=512, num_anchors=3): super(BboxHead, self).__init__() self.conv1x1 = nn.Conv2d(inchannels, num_anchors * 4, kernel_size=(1, 1), stride=1, padding=0) def forward(self, x): out = self.conv1x1(x) out = out.permute(0, 2, 3, 1).contiguous() return out.view(out.shape[0], -1, 4) class LandmarkHead(nn.Module): def __init__(self, inchannels=512, num_anchors=3): super(LandmarkHead, self).__init__() self.conv1x1 = nn.Conv2d(inchannels, num_anchors * 10, kernel_size=(1, 1), stride=1, padding=0) def forward(self, x): out = self.conv1x1(x) out = out.permute(0, 2, 3, 1).contiguous() return out.view(out.shape[0], -1, 10) def make_class_head(fpn_num=3, inchannels=64, anchor_num=2): classhead = nn.ModuleList() for i in range(fpn_num): classhead.append(ClassHead(inchannels, anchor_num)) return classhead def make_bbox_head(fpn_num=3, inchannels=64, anchor_num=2): bboxhead = nn.ModuleList() for i in range(fpn_num): bboxhead.append(BboxHead(inchannels, anchor_num)) return bboxhead def make_landmark_head(fpn_num=3, inchannels=64, anchor_num=2): landmarkhead = nn.ModuleList() for i in range(fpn_num): landmarkhead.append(LandmarkHead(inchannels, anchor_num)) return landmarkhead