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Zero
Running
on
Zero
| import torch | |
| import torch.nn as nn | |
| from torch.nn import init | |
| import functools | |
| # Defines the Unet generator. | |
| # |num_downs|: number of downsamplings in UNet. For example, | |
| # if |num_downs| == 7, image of size 128x128 will become of size 1x1 | |
| # at the bottleneck | |
| class UnetGenerator(nn.Module): | |
| def __init__(self, input_nc, output_nc, num_downs, ngf=64, | |
| norm_layer=nn.BatchNorm2d, use_dropout=False): | |
| super(UnetGenerator, self).__init__() | |
| # construct unet structure | |
| unet_block = UnetSkipConnectionBlock(ngf * 8, ngf * 8, input_nc=None, submodule=None, norm_layer=norm_layer, innermost=True) | |
| for i in range(num_downs - 5): | |
| unet_block = UnetSkipConnectionBlock(ngf * 8, ngf * 8, input_nc=None, submodule=unet_block, norm_layer=norm_layer, use_dropout=use_dropout) | |
| unet_block = UnetSkipConnectionBlock(ngf * 4, ngf * 8, input_nc=None, submodule=unet_block, norm_layer=norm_layer) | |
| unet_block = UnetSkipConnectionBlock(ngf * 2, ngf * 4, input_nc=None, submodule=unet_block, norm_layer=norm_layer) | |
| unet_block = UnetSkipConnectionBlock(ngf, ngf * 2, input_nc=None, submodule=unet_block, norm_layer=norm_layer) | |
| unet_block = UnetSkipConnectionBlock(output_nc, ngf, input_nc=input_nc, submodule=unet_block, outermost=True, norm_layer=norm_layer) | |
| self.model = unet_block | |
| def forward(self, input): | |
| return self.model(input) | |
| def forward(self, input): | |
| return self.model(input) | |
| # Defines the submodule with skip connection. | |
| # X -------------------identity---------------------- X | |
| # |-- downsampling -- |submodule| -- upsampling --| | |
| class UnetSkipConnectionBlock(nn.Module): | |
| def __init__(self, outer_nc, inner_nc, input_nc=None, | |
| submodule=None, outermost=False, innermost=False, norm_layer=nn.BatchNorm2d, use_dropout=False): | |
| super(UnetSkipConnectionBlock, self).__init__() | |
| self.outermost = outermost | |
| if type(norm_layer) == functools.partial: | |
| use_bias = norm_layer.func == nn.InstanceNorm2d | |
| else: | |
| use_bias = norm_layer == nn.InstanceNorm2d | |
| if input_nc is None: | |
| input_nc = outer_nc | |
| downconv = nn.Conv2d(input_nc, inner_nc, kernel_size=4, | |
| stride=2, padding=1, bias=use_bias) | |
| downrelu = nn.LeakyReLU(0.2, True) | |
| downnorm = norm_layer(inner_nc) | |
| uprelu = nn.ReLU(True) | |
| upnorm = norm_layer(outer_nc) | |
| if outermost: | |
| upconv = nn.ConvTranspose2d(inner_nc * 2, outer_nc, | |
| kernel_size=4, stride=2, | |
| padding=1) | |
| down = [downconv] | |
| up = [uprelu, upconv, nn.Tanh()] | |
| model = down + [submodule] + up | |
| elif innermost: | |
| upconv = nn.ConvTranspose2d(inner_nc, outer_nc, | |
| kernel_size=4, stride=2, | |
| padding=1, bias=use_bias) | |
| down = [downrelu, downconv] | |
| up = [uprelu, upconv, upnorm] | |
| model = down + up | |
| else: | |
| upconv = nn.ConvTranspose2d(inner_nc * 2, outer_nc, | |
| kernel_size=4, stride=2, | |
| padding=1, bias=use_bias) | |
| down = [downrelu, downconv, downnorm] | |
| up = [uprelu, upconv, upnorm] | |
| if use_dropout: | |
| model = down + [submodule] + up + [nn.Dropout(0.5)] | |
| else: | |
| model = down + [submodule] + up | |
| self.model = nn.Sequential(*model) | |
| def forward(self, x): | |
| if self.outermost: | |
| return self.model(x) | |
| else: | |
| return torch.cat([x, self.model(x)], 1) | |