Spaces:
Runtime error
Runtime error
import functools | |
import torch | |
import torch.nn as nn | |
def count_params(model): | |
total_params = sum(p.numel() for p in model.parameters()) | |
return total_params | |
class ActNorm(nn.Module): | |
def __init__( | |
self, num_features, logdet=False, affine=True, allow_reverse_init=False | |
): | |
assert affine | |
super().__init__() | |
self.logdet = logdet | |
self.loc = nn.Parameter(torch.zeros(1, num_features, 1, 1)) | |
self.scale = nn.Parameter(torch.ones(1, num_features, 1, 1)) | |
self.allow_reverse_init = allow_reverse_init | |
self.register_buffer("initialized", torch.tensor(0, dtype=torch.uint8)) | |
def initialize(self, input): | |
with torch.no_grad(): | |
flatten = input.permute(1, 0, 2, 3).contiguous().view(input.shape[1], -1) | |
mean = ( | |
flatten.mean(1) | |
.unsqueeze(1) | |
.unsqueeze(2) | |
.unsqueeze(3) | |
.permute(1, 0, 2, 3) | |
) | |
std = ( | |
flatten.std(1) | |
.unsqueeze(1) | |
.unsqueeze(2) | |
.unsqueeze(3) | |
.permute(1, 0, 2, 3) | |
) | |
self.loc.data.copy_(-mean) | |
self.scale.data.copy_(1 / (std + 1e-6)) | |
def forward(self, input, reverse=False): | |
if reverse: | |
return self.reverse(input) | |
if len(input.shape) == 2: | |
input = input[:, :, None, None] | |
squeeze = True | |
else: | |
squeeze = False | |
_, _, height, width = input.shape | |
if self.training and self.initialized.item() == 0: | |
self.initialize(input) | |
self.initialized.fill_(1) | |
h = self.scale * (input + self.loc) | |
if squeeze: | |
h = h.squeeze(-1).squeeze(-1) | |
if self.logdet: | |
log_abs = torch.log(torch.abs(self.scale)) | |
logdet = height * width * torch.sum(log_abs) | |
logdet = logdet * torch.ones(input.shape[0]).to(input) | |
return h, logdet | |
return h | |
def reverse(self, output): | |
if self.training and self.initialized.item() == 0: | |
if not self.allow_reverse_init: | |
raise RuntimeError( | |
"Initializing ActNorm in reverse direction is " | |
"disabled by default. Use allow_reverse_init=True to enable." | |
) | |
else: | |
self.initialize(output) | |
self.initialized.fill_(1) | |
if len(output.shape) == 2: | |
output = output[:, :, None, None] | |
squeeze = True | |
else: | |
squeeze = False | |
h = output / self.scale - self.loc | |
if squeeze: | |
h = h.squeeze(-1).squeeze(-1) | |
return h | |
class AbstractEncoder(nn.Module): | |
def __init__(self): | |
super().__init__() | |
def encode(self, *args, **kwargs): | |
raise NotImplementedError | |
class Labelator(AbstractEncoder): | |
"""Net2Net Interface for Class-Conditional Model""" | |
def __init__(self, n_classes, quantize_interface=True): | |
super().__init__() | |
self.n_classes = n_classes | |
self.quantize_interface = quantize_interface | |
def encode(self, c): | |
c = c[:, None] | |
if self.quantize_interface: | |
return c, None, [None, None, c.long()] | |
return c | |
class SOSProvider(AbstractEncoder): | |
# for unconditional training | |
def __init__(self, sos_token, quantize_interface=True): | |
super().__init__() | |
self.sos_token = sos_token | |
self.quantize_interface = quantize_interface | |
def encode(self, x): | |
# get batch size from data and replicate sos_token | |
c = torch.ones(x.shape[0], 1) * self.sos_token | |
c = c.long().to(x.device) | |
if self.quantize_interface: | |
return c, None, [None, None, c] | |
return c | |
def weights_init(m): | |
classname = m.__class__.__name__ | |
if classname.find("Conv") != -1: | |
nn.init.normal_(m.weight.data, 0.0, 0.02) | |
elif classname.find("BatchNorm") != -1: | |
nn.init.normal_(m.weight.data, 1.0, 0.02) | |
nn.init.constant_(m.bias.data, 0) | |
class NLayerDiscriminator(nn.Module): | |
"""Defines a PatchGAN discriminator as in Pix2Pix | |
--> see https://github.com/junyanz/pytorch-CycleGAN-and-pix2pix/blob/master/models/networks.py | |
""" | |
def __init__(self, input_nc=3, ndf=64, n_layers=3, use_actnorm=False): | |
"""Construct a PatchGAN discriminator | |
Parameters: | |
input_nc (int) -- the number of channels in input images | |
ndf (int) -- the number of filters in the last conv layer | |
n_layers (int) -- the number of conv layers in the discriminator | |
norm_layer -- normalization layer | |
""" | |
super(NLayerDiscriminator, self).__init__() | |
if not use_actnorm: | |
norm_layer = nn.BatchNorm2d | |
else: | |
norm_layer = ActNorm | |
if ( | |
type(norm_layer) == functools.partial | |
): # no need to use bias as BatchNorm2d has affine parameters | |
use_bias = norm_layer.func != nn.BatchNorm2d | |
else: | |
use_bias = norm_layer != nn.BatchNorm2d | |
kw = 4 | |
padw = 1 | |
sequence = [ | |
nn.Conv2d(input_nc, ndf, kernel_size=kw, stride=2, padding=padw), | |
nn.LeakyReLU(0.2, True), | |
] | |
nf_mult = 1 | |
nf_mult_prev = 1 | |
for n in range(1, n_layers): # gradually increase the number of filters | |
nf_mult_prev = nf_mult | |
nf_mult = min(2**n, 8) | |
sequence += [ | |
nn.Conv2d( | |
ndf * nf_mult_prev, | |
ndf * nf_mult, | |
kernel_size=kw, | |
stride=2, | |
padding=padw, | |
bias=use_bias, | |
), | |
norm_layer(ndf * nf_mult), | |
nn.LeakyReLU(0.2, True), | |
] | |
nf_mult_prev = nf_mult | |
nf_mult = min(2**n_layers, 8) | |
sequence += [ | |
nn.Conv2d( | |
ndf * nf_mult_prev, | |
ndf * nf_mult, | |
kernel_size=kw, | |
stride=1, | |
padding=padw, | |
bias=use_bias, | |
), | |
norm_layer(ndf * nf_mult), | |
nn.LeakyReLU(0.2, True), | |
] | |
sequence += [ | |
nn.Conv2d(ndf * nf_mult, 1, kernel_size=kw, stride=1, padding=padw) | |
] # output 1 channel prediction map | |
self.main = nn.Sequential(*sequence) | |
def forward(self, input): | |
"""Standard forward.""" | |
return self.main(input) | |