StyleNeRF / training /networks.py
Jiatao Gu
fix bug for cpu running
df44b7d
# Copyright (c) Facebook, Inc. and its affiliates. All Rights Reserved
# Copyright (c) 2021, NVIDIA CORPORATION. All rights reserved.
#
# NVIDIA CORPORATION and its licensors retain all intellectual property
# and proprietary rights in and to this software, related documentation
# and any modifications thereto. Any use, reproduction, disclosure or
# distribution of this software and related documentation without an express
# license agreement from NVIDIA CORPORATION is strictly prohibited.
from pickle import NONE
from re import X
from sndhdr import whathdr
import numpy as np
import math
import scipy.signal
import scipy.optimize
from numpy import core
from numpy.lib.arraysetops import isin
import torch
import torch.nn.functional as F
from torch.overrides import is_tensor_method_or_property
from einops import repeat
from dnnlib import camera, util, geometry
from torch_utils import misc
from torch_utils import persistence
from torch_utils.ops import conv2d_resample
from torch_utils.ops import upfirdn2d
from torch_utils.ops import bias_act
from torch_utils.ops import fma
from torch_utils.ops import filtered_lrelu
#----------------------------------------------------------------------------
@misc.profiled_function
def normalize_2nd_moment(x, dim=1, eps=1e-8):
return x * (x.square().mean(dim=dim, keepdim=True) + eps).rsqrt()
@misc.profiled_function
def conv3d(x, w, up=1, down=1, padding=0, groups=1):
if up > 1:
x = F.interpolate(x, scale_factor=up, mode='trilinear', align_corners=True)
x = F.conv3d(x, w, padding=padding, groups=groups)
if down > 1:
x = F.interpolate(x, scale_factor=1./float(down), mode='trilinear', align_corners=True)
return x
#----------------------------------------------------------------------------
@misc.profiled_function
def modulated_conv2d(
x, # Input tensor of shape [batch_size, in_channels, in_height, in_width].
weight, # Weight tensor of shape [out_channels, in_channels, kernel_height, kernel_width].
styles, # Modulation coefficients of shape [batch_size, in_channels].
noise = None, # Optional noise tensor to add to the output activations.
up = 1, # Integer upsampling factor.
down = 1, # Integer downsampling factor.
padding = 0, # Padding with respect to the upsampled image.
resample_filter = None, # Low-pass filter to apply when resampling activations. Must be prepared beforehand by calling upfirdn2d.setup_filter().
demodulate = True, # Apply weight demodulation?
flip_weight = True, # False = convolution, True = correlation (matches torch.nn.functional.conv2d) ????????
fused_modconv = True, # Perform modulation, convolution, and demodulation as a single fused operation?
mode = '2d', # modulated 2d/3d conv or MLP
**unused,
):
batch_size = x.shape[0]
if mode == '3d':
_, in_channels, kd, kh, kw = weight.shape
else:
_, in_channels, kh, kw = weight.shape
# Pre-normalize inputs to avoid FP16 overflow.
if x.dtype == torch.float16 and demodulate:
weight_sizes = in_channels * kh * kw if mode != '3d' else in_channels * kd * kh * kw
weight = weight * (1 / np.sqrt(weight_sizes) / weight.norm(float('inf'), dim=[1,2,3], keepdim=True)) # max_Ikk
styles = styles / styles.norm(float('inf'), dim=1, keepdim=True) # max_I
# Calculate per-sample weights and demodulation coefficients.
w = None
dcoefs = None
if mode != '3d':
rsizes, ssizes = [-1, 1, 1], [2, 3, 4]
else:
rsizes, ssizes = [-1, 1, 1, 1], [2, 3, 4, 5]
if demodulate or fused_modconv: # if not fused, skip
w = weight.unsqueeze(0) * styles.reshape(batch_size, 1, *rsizes)
if demodulate:
dcoefs = (w.square().sum(dim=ssizes) + 1e-8).rsqrt() # [NO]
if demodulate and fused_modconv:
w = w * dcoefs.reshape(batch_size, *rsizes, 1) # [NOIkk] (batch_size, out_channels, in_channels, kernel_size, kernel_size)
# Execute by scaling the activations before and after the convolution.
if not fused_modconv:
x = x * styles.to(x.dtype).reshape(batch_size, *rsizes)
if mode == '2d':
x = conv2d_resample.conv2d_resample(x=x, w=weight.to(x.dtype), f=resample_filter, up=up, down=down, padding=padding, flip_weight=flip_weight)
elif mode == '3d':
x = conv3d(x=x, w=weight.to(x.dtype), up=up, down=down, padding=padding)
else:
raise NotImplementedError
if demodulate and noise is not None:
x = fma.fma(x, dcoefs.to(x.dtype).reshape(batch_size, *rsizes), noise.to(x.dtype)) # fused multiply add
elif demodulate:
x = x * dcoefs.to(x.dtype).reshape(batch_size, *rsizes)
elif noise is not None:
x = x.add_(noise.to(x.dtype))
return x
# Execute as one fused op using grouped convolution.
with misc.suppress_tracer_warnings(): # this value will be treated as a constant
batch_size = int(batch_size)
x = x.reshape(1, -1, *x.shape[2:])
w = w.reshape(-1, *w.shape[2:])
if mode == '2d':
x = conv2d_resample.conv2d_resample(x=x, w=w.to(x.dtype), f=resample_filter, up=up, down=down, padding=padding, groups=batch_size, flip_weight=flip_weight)
elif mode == '3d':
x = conv3d(x=x, w=w.to(x.dtype), up=up, down=down, padding=padding, groups=batch_size)
x = x.reshape(batch_size, -1, *x.shape[2:])
if noise is not None:
x = x.add_(noise)
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class FullyConnectedLayer(torch.nn.Module):
def __init__(self,
in_features, # Number of input features.
out_features, # Number of output features.
bias = True, # Apply additive bias before the activation function?
activation = 'linear', # Activation function: 'relu', 'lrelu', etc.
lr_multiplier = 1, # Learning rate multiplier.
bias_init = 0, # Initial value for the additive bias.
):
super().__init__()
self.activation = activation
self.weight = torch.nn.Parameter(torch.randn([out_features, in_features]) / lr_multiplier)
self.bias = torch.nn.Parameter(torch.full([out_features], np.float32(bias_init))) if bias else None
self.weight_gain = lr_multiplier / np.sqrt(in_features)
self.bias_gain = lr_multiplier
def forward(self, x):
w = self.weight.to(x.dtype) * self.weight_gain
b = self.bias
if b is not None:
b = b.to(x.dtype)
if self.bias_gain != 1:
b = b * self.bias_gain
if self.activation == 'linear' and b is not None:
x = torch.addmm(b.unsqueeze(0), x, w.t())
else:
x = x.matmul(w.t())
x = bias_act.bias_act(x, b, act=self.activation)
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class Conv2dLayer(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels.
out_channels, # Number of output channels.
kernel_size, # Width and height of the convolution kernel.
bias = True, # Apply additive bias before the activation function?
activation = 'linear', # Activation function: 'relu', 'lrelu', etc.
up = 1, # Integer upsampling factor.
down = 1, # Integer downsampling factor.
resample_filter = [1,3,3,1], # Low-pass filter to apply when resampling activations.
conv_clamp = None, # Clamp the output to +-X, None = disable clamping.
channels_last = False, # Expect the input to have memory_format=channels_last?
trainable = True, # Update the weights of this layer during training?
mode = '2d',
**unused
):
super().__init__()
self.activation = activation
self.up = up
self.down = down
self.conv_clamp = conv_clamp
self.register_buffer('resample_filter', upfirdn2d.setup_filter(resample_filter))
self.padding = kernel_size // 2
self.weight_gain = 1 / np.sqrt(in_channels * (kernel_size ** 2))
self.act_gain = bias_act.activation_funcs[activation].def_gain
self.mode = mode
weight_shape = [out_channels, in_channels, kernel_size, kernel_size]
if mode == '3d':
weight_shape += [kernel_size]
memory_format = torch.channels_last if channels_last else torch.contiguous_format
weight = torch.randn(weight_shape).to(memory_format=memory_format)
bias = torch.zeros([out_channels]) if bias else None
if trainable:
self.weight = torch.nn.Parameter(weight)
self.bias = torch.nn.Parameter(bias) if bias is not None else None
else:
self.register_buffer('weight', weight)
if bias is not None:
self.register_buffer('bias', bias)
else:
self.bias = None
def forward(self, x, gain=1):
w = self.weight * self.weight_gain
b = self.bias.to(x.dtype) if self.bias is not None else None
flip_weight = (self.up == 1) # slightly faster
if self.mode == '2d':
x = conv2d_resample.conv2d_resample(x=x, w=w.to(x.dtype), f=self.resample_filter, up=self.up, down=self.down, padding=self.padding, flip_weight=flip_weight)
elif self.mode == '3d':
x = conv3d(x=x, w=w.to(x.dtype), up=self.up, down=self.down, padding=self.padding)
act_gain = self.act_gain * gain
act_clamp = self.conv_clamp * gain if self.conv_clamp is not None else None
x = bias_act.bias_act(x, b, act=self.activation, gain=act_gain, clamp=act_clamp)
return x
# ---------------------------------------------------------------------------
@persistence.persistent_class
class Blur(torch.nn.Module):
def __init__(self):
super().__init__()
f = torch.Tensor([1, 2, 1])
self.register_buffer('f', f)
def forward(self, x):
from kornia.filters import filter2d
f = self.f
f = f[None, None, :] * f [None, :, None]
return filter2d(x, f, normalized=True)
#----------------------------------------------------------------------------
@persistence.persistent_class
class MappingNetwork(torch.nn.Module):
def __init__(self,
z_dim, # Input latent (Z) dimensionality, 0 = no latent.
c_dim, # Conditioning label (C) dimensionality, 0 = no label.
w_dim, # Intermediate latent (W) dimensionality.
num_ws, # Number of intermediate latents to output, None = do not broadcast.
num_layers = 8, # Number of mapping layers.
embed_features = None, # Label embedding dimensionality, None = same as w_dim.
layer_features = None, # Number of intermediate features in the mapping layers, None = same as w_dim.
activation = 'lrelu', # Activation function: 'relu', 'lrelu', etc.
lr_multiplier = 0.01, # Learning rate multiplier for the mapping layers.
w_avg_beta = 0.995, # Decay for tracking the moving average of W during training, None = do not track.
**unused,
):
super().__init__()
self.z_dim = z_dim
self.c_dim = c_dim
self.w_dim = w_dim
self.num_ws = num_ws
self.num_layers = num_layers
self.w_avg_beta = w_avg_beta
if embed_features is None:
embed_features = w_dim
if c_dim == 0:
embed_features = 0
if layer_features is None:
layer_features = w_dim
features_list = [z_dim + embed_features] + [layer_features] * (num_layers - 1) + [w_dim]
if c_dim > 0: # project label condition
self.embed = FullyConnectedLayer(c_dim, embed_features)
for idx in range(num_layers):
in_features = features_list[idx]
out_features = features_list[idx + 1]
layer = FullyConnectedLayer(in_features, out_features, activation=activation, lr_multiplier=lr_multiplier)
setattr(self, f'fc{idx}', layer)
if num_ws is not None and w_avg_beta is not None:
self.register_buffer('w_avg', torch.zeros([w_dim]))
def forward(self, z=None, c=None, truncation_psi=1, truncation_cutoff=None, skip_w_avg_update=False, styles=None, **unused_kwargs):
if styles is not None:
return styles
# Embed, normalize, and concat inputs.
x = None
with torch.autograd.profiler.record_function('input'):
if self.z_dim > 0:
misc.assert_shape(z, [None, self.z_dim])
x = normalize_2nd_moment(z.to(torch.float32)) # normalize z to shpere
if self.c_dim > 0:
misc.assert_shape(c, [None, self.c_dim])
y = normalize_2nd_moment(self.embed(c.to(torch.float32)))
x = torch.cat([x, y], dim=1) if x is not None else y
# Main layers.
for idx in range(self.num_layers):
layer = getattr(self, f'fc{idx}')
x = layer(x)
# Update moving average of W.
if self.w_avg_beta is not None and self.training and not skip_w_avg_update:
with torch.autograd.profiler.record_function('update_w_avg'):
self.w_avg.copy_(x.detach().mean(dim=0).lerp(self.w_avg, self.w_avg_beta))
# Broadcast.
if self.num_ws is not None:
with torch.autograd.profiler.record_function('broadcast'):
x = x.unsqueeze(1).repeat([1, self.num_ws, 1])
# Apply truncation.
if truncation_psi != 1:
with torch.autograd.profiler.record_function('truncate'):
assert self.w_avg_beta is not None
if self.num_ws is None or truncation_cutoff is None:
x = self.w_avg.lerp(x, truncation_psi)
else:
x[:, :truncation_cutoff] = self.w_avg.lerp(x[:, :truncation_cutoff], truncation_psi)
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class SynthesisLayer(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels.
out_channels, # Number of output channels.
w_dim, # Intermediate latent (W) dimensionality.
resolution, # Resolution of this layer.
kernel_size = 3, # Convolution kernel size.
up = 1, # Integer upsampling factor.
use_noise = True, # Enable noise input?
activation = 'lrelu', # Activation function: 'relu', 'lrelu', etc.
resample_filter = [1,3,3,1], # Low-pass filter to apply when resampling activations.
conv_clamp = None, # Clamp the output of convolution layers to +-X, None = disable clamping.
channels_last = False, # Use channels_last format for the weights?
upsample_mode = 'default', # [default, bilinear, ray_comm, ray_attn, ray_penc]
use_group = False,
magnitude_ema_beta = -1, # -1 means not using magnitude ema
mode = '2d', # choose from 1d, 2d or 3d
**unused_kwargs
):
super().__init__()
self.resolution = resolution
self.up = up
self.use_noise = use_noise
self.activation = activation
self.conv_clamp = conv_clamp
self.upsample_mode = upsample_mode
self.mode = mode
self.register_buffer('resample_filter', upfirdn2d.setup_filter(resample_filter))
if up == 2:
if 'pixelshuffle' in upsample_mode:
self.adapter = torch.nn.Sequential(
Conv2dLayer(out_channels, out_channels // 4, kernel_size=1, activation=activation),
Conv2dLayer(out_channels // 4, out_channels * 4, kernel_size=1, activation='linear'),
)
elif upsample_mode == 'liif':
from dnnlib.geometry import get_grids, local_ensemble
pi = get_grids(self.resolution//2, self.resolution//2, 'cpu', align=False).transpose(0,1)
po = get_grids(self.resolution, self.resolution, 'cpu', align=False).transpose(0,1)
diffs, coords, coeffs = local_ensemble(pi, po, self.resolution)
self.diffs = torch.nn.Parameter(diffs, requires_grad=False)
self.coords = torch.nn.Parameter(coords.float(), requires_grad=False)
self.coeffs = torch.nn.Parameter(coeffs, requires_grad=False)
add_dim = 2
self.adapter = torch.nn.Sequential(
Conv2dLayer(out_channels + add_dim, out_channels // 2, kernel_size=1, activation=activation),
Conv2dLayer(out_channels // 2, out_channels, kernel_size=1, activation='linear'),
)
elif 'nn_cat' in upsample_mode:
self.adapter = torch.nn.Sequential(
Conv2dLayer(out_channels * 2, out_channels // 4, kernel_size=1, activation=activation),
Conv2dLayer(out_channels // 4, out_channels, kernel_size=1, activation='linear'),
)
elif 'ada' in upsample_mode:
self.adapter = torch.nn.Sequential(
Conv2dLayer(out_channels, 8, kernel_size=1, activation=activation),
Conv2dLayer(8, out_channels, kernel_size=1, activation='linear')
)
self.adapter[1].weight.data.zero_()
if 'blur' in upsample_mode:
self.blur = Blur()
self.padding = kernel_size // 2
self.groups = 2 if use_group else 1
self.act_gain = bias_act.activation_funcs[activation].def_gain
self.affine = FullyConnectedLayer(w_dim, in_channels, bias_init=1)
memory_format = torch.channels_last if channels_last else torch.contiguous_format
weight_sizes = [out_channels // self.groups, in_channels, kernel_size, kernel_size]
if self.mode == '3d':
weight_sizes += [kernel_size]
weight = torch.randn(weight_sizes).to(memory_format=memory_format)
self.weight = torch.nn.Parameter(weight)
if use_noise:
if self.mode == '2d':
noise_sizes = [resolution, resolution]
elif self.mode == '3d':
noise_sizes = [resolution, resolution, resolution]
else:
raise NotImplementedError('not support for MLP')
self.register_buffer('noise_const', torch.randn(noise_sizes)) # HACK: for safety reasons
self.noise_strength = torch.nn.Parameter(torch.zeros([]))
self.bias = torch.nn.Parameter(torch.zeros([out_channels]))
self.magnitude_ema_beta = magnitude_ema_beta
if magnitude_ema_beta > 0:
self.register_buffer('w_avg', torch.ones([])) # TODO: name for compitibality
def forward(self, x, w, noise_mode='random', fused_modconv=True, gain=1, skip_up=False, input_noise=None, **unused_kwargs):
assert noise_mode in ['random', 'const', 'none']
batch_size = x.size(0)
if (self.magnitude_ema_beta > 0):
if self.training: # updating EMA.
with torch.autograd.profiler.record_function('update_magnitude_ema'):
magnitude_cur = x.detach().to(torch.float32).square().mean()
self.w_avg.copy_(magnitude_cur.lerp(self.w_avg, self.magnitude_ema_beta))
input_gain = self.w_avg.rsqrt()
x = x * input_gain
styles = self.affine(w) # Batch x style_dim
if styles.size(0) < x.size(0): # for repeating
assert (x.size(0) // styles.size(0) * styles.size(0) == x.size(0))
styles = repeat(styles, 'b c -> (b s) c', s=x.size(0) // styles.size(0))
up = self.up if not skip_up else 1
use_default = (self.upsample_mode == 'default')
noise = None
resample_filter = None
if use_default and (up > 1):
resample_filter = self.resample_filter
if self.use_noise:
if input_noise is not None:
noise = input_noise * self.noise_strength
elif noise_mode == 'random':
noise_sizes = [x.shape[0], 1, up * x.shape[2], up * x.shape[3]]
if self.mode == '3d':
noise_sizes += [up * x.shape[4]]
noise = torch.randn(noise_sizes, device=x.device) * self.noise_strength
elif noise_mode == 'const':
noise = self.noise_const * self.noise_strength
if noise.shape[-1] < (up * x.shape[3]):
noise = repeat(noise, 'h w -> h (s w)', s=up*x.shape[3]//noise.shape[-1])
flip_weight = (up == 1) # slightly faster
x = modulated_conv2d(
x=x, weight=self.weight, styles=styles,
noise=noise if (use_default and not skip_up) else None,
up=up if use_default else 1,
padding=self.padding,
resample_filter=resample_filter,
flip_weight=flip_weight,
fused_modconv=fused_modconv,
groups=self.groups,
mode=self.mode
)
if (up == 2) and (not use_default):
resolution = x.size(-1) * 2
if 'bilinear' in self.upsample_mode:
x = F.interpolate(x, size=(resolution, resolution), mode='bilinear', align_corners=True)
elif 'nearest' in self.upsample_mode:
x = F.interpolate(x, size=(resolution, resolution), mode='nearest')
x = upfirdn2d.filter2d(x, self.resample_filter)
elif 'bicubic' in self.upsample_mode:
x = F.interpolate(x, size=(resolution, resolution), mode='bicubic', align_corners=True)
elif 'pixelshuffle' in self.upsample_mode: # does not have rotation invariance
x = F.interpolate(x, size=(resolution, resolution), mode='nearest') + torch.pixel_shuffle(self.adapter(x), 2)
if not 'noblur' in self.upsample_mode:
x = upfirdn2d.filter2d(x, self.resample_filter)
elif 'nn_cat' in self.upsample_mode:
x_pad = x.new_zeros(*x.size()[:2], x.size(-2)+2, x.size(-1)+2)
x_pad[...,1:-1,1:-1] = x
xl, xu, xd, xr = x_pad[..., 1:-1, :-2], x_pad[..., :-2, 1:-1], x_pad[..., 2:, 1:-1], x_pad[..., 1:-1, 2:]
x1, x2, x3, x4 = xl + xu, xu + xr, xl + xd, xr + xd
xb = torch.stack([x1, x2, x3, x4], 2) / 2
xb = torch.pixel_shuffle(xb.view(xb.size(0), -1, xb.size(-2), xb.size(-1)), 2)
xa = F.interpolate(x, size=(resolution, resolution), mode='nearest')
x = xa + self.adapter(torch.cat([xa, xb], 1))
if not 'noblur' in self.upsample_mode:
x = upfirdn2d.filter2d(x, self.resample_filter)
elif self.upsample_mode == 'liif': # this is an old version
x = torch.stack([x[..., self.coords[j,:,:,0].long(), self.coords[j,:,:,1].long()] for j in range(4)], 0)
d = self.diffs[:, None].type_as(x).repeat(1,batch_size,1,1,1).permute(0,1,4,2,3)
x = self.adapter(torch.cat([x, d.type_as(x)], 2).reshape(batch_size*4,-1,*x.size()[-2:]))
x = (x.reshape(4,batch_size,*x.size()[-3:]) * self.coeffs[:,None,None].type_as(x)).sum(0)
else:
raise NotImplementedError
if up == 2:
if 'ada' in self.upsample_mode:
x = x + self.adapter(x)
if 'blur' in self.upsample_mode:
x = self.blur(x)
if (noise is not None) and (not use_default) and (not skip_up):
x = x.add_(noise.type_as(x))
act_gain = self.act_gain * gain
act_clamp = self.conv_clamp * gain if self.conv_clamp is not None else None
x = bias_act.bias_act(x, self.bias.to(x.dtype), act=self.activation, gain=act_gain, clamp=act_clamp)
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class SynthesisLayer3(torch.nn.Module):
"""copy from the stylegan3 codebase with minor changes"""
def __init__(self,
w_dim, # Intermediate latent (W) dimensionality.
is_torgb, # Is this the final ToRGB layer?
is_critically_sampled, # Does this layer use critical sampling?
use_fp16, # Does this layer use FP16?
# Input & output specifications.
in_channels, # Number of input channels.
out_channels, # Number of output channels.
in_size, # Input spatial size: int or [width, height].
out_size, # Output spatial size: int or [width, height].
in_sampling_rate, # Input sampling rate (s).
out_sampling_rate, # Output sampling rate (s).
in_cutoff, # Input cutoff frequency (f_c).
out_cutoff, # Output cutoff frequency (f_c).
in_half_width, # Input transition band half-width (f_h).
out_half_width, # Output Transition band half-width (f_h).
# Hyperparameters.
kernel_size = 3, # Convolution kernel size. Ignored for final the ToRGB layer.
filter_size = 6, # Low-pass filter size relative to the lower resolution when up/downsampling.
lrelu_upsampling = 2, # Relative sampling rate for leaky ReLU. Ignored for final the ToRGB layer.
use_radial_filters = False, # Use radially symmetric downsampling filter? Ignored for critically sampled layers.
conv_clamp = 256, # Clamp the output to [-X, +X], None = disable clamping.
magnitude_ema_beta = 0.999, # Decay rate for the moving average of input magnitudes.
**unused_kwargs,
):
super().__init__()
self.w_dim = w_dim
self.is_torgb = is_torgb
self.is_critically_sampled = is_critically_sampled
self.use_fp16 = use_fp16
self.in_channels = in_channels
self.out_channels = out_channels
self.in_size = np.broadcast_to(np.asarray(in_size), [2])
self.out_size = np.broadcast_to(np.asarray(out_size), [2])
self.in_sampling_rate = in_sampling_rate
self.out_sampling_rate = out_sampling_rate
self.tmp_sampling_rate = max(in_sampling_rate, out_sampling_rate) * (1 if is_torgb else lrelu_upsampling)
self.in_cutoff = in_cutoff
self.out_cutoff = out_cutoff
self.in_half_width = in_half_width
self.out_half_width = out_half_width
self.conv_kernel = 1 if is_torgb else kernel_size
self.conv_clamp = conv_clamp
self.magnitude_ema_beta = magnitude_ema_beta
# Setup parameters and buffers.
self.affine = FullyConnectedLayer(self.w_dim, self.in_channels, bias_init=1)
self.weight = torch.nn.Parameter(torch.randn([self.out_channels, self.in_channels, self.conv_kernel, self.conv_kernel]))
self.bias = torch.nn.Parameter(torch.zeros([self.out_channels]))
if magnitude_ema_beta > 0:
self.register_buffer('w_avg', torch.ones([]))
# Design upsampling filter.
self.up_factor = int(np.rint(self.tmp_sampling_rate / self.in_sampling_rate))
assert self.in_sampling_rate * self.up_factor == self.tmp_sampling_rate
self.up_taps = filter_size * self.up_factor if self.up_factor > 1 and not self.is_torgb else 1
self.register_buffer('up_filter', self.design_lowpass_filter(
numtaps=self.up_taps, cutoff=self.in_cutoff, width=self.in_half_width*2, fs=self.tmp_sampling_rate))
# Design downsampling filter.
self.down_factor = int(np.rint(self.tmp_sampling_rate / self.out_sampling_rate))
assert self.out_sampling_rate * self.down_factor == self.tmp_sampling_rate
self.down_taps = filter_size * self.down_factor if self.down_factor > 1 and not self.is_torgb else 1
self.down_radial = use_radial_filters and not self.is_critically_sampled
self.register_buffer('down_filter', self.design_lowpass_filter(
numtaps=self.down_taps, cutoff=self.out_cutoff, width=self.out_half_width*2, fs=self.tmp_sampling_rate, radial=self.down_radial))
# Compute padding.
pad_total = (self.out_size - 1) * self.down_factor + 1 # Desired output size before downsampling.
pad_total -= (self.in_size + self.conv_kernel - 1) * self.up_factor # Input size after upsampling.
pad_total += self.up_taps + self.down_taps - 2 # Size reduction caused by the filters.
pad_lo = (pad_total + self.up_factor) // 2 # Shift sample locations according to the symmetric interpretation (Appendix C.3).
pad_hi = pad_total - pad_lo
self.padding = [int(pad_lo[0]), int(pad_hi[0]), int(pad_lo[1]), int(pad_hi[1])]
def forward(self, x, w, noise_mode='random', force_fp32=False, **unused_kwargs):
assert noise_mode in ['random', 'const', 'none'] # unused
misc.assert_shape(x, [None, self.in_channels, int(self.in_size[1]), int(self.in_size[0])])
misc.assert_shape(w, [x.shape[0], self.w_dim])
# Track input magnitude.
if (self.magnitude_ema_beta > 0):
if self.training: # updating EMA.
with torch.autograd.profiler.record_function('update_magnitude_ema'):
magnitude_cur = x.detach().to(torch.float32).square().mean()
self.w_avg.copy_(magnitude_cur.lerp(self.w_avg, self.magnitude_ema_beta))
input_gain = self.w_avg.rsqrt()
x = x * input_gain
# Execute affine layer.
styles = self.affine(w)
if self.is_torgb:
weight_gain = 1 / np.sqrt(self.in_channels * (self.conv_kernel ** 2))
styles = styles * weight_gain
# Execute modulated conv2d.
dtype = torch.float16 if (self.use_fp16 and not force_fp32 and x.device.type == 'cuda') else torch.float32
x = modulated_conv2d(x=x.to(dtype), weight=self.weight, styles=styles, padding=self.conv_kernel-1, up=1, fused_modconv=True)
# Execute bias, filtered leaky ReLU, and clamping.
gain = 1 if self.is_torgb else np.sqrt(2)
slope = 1 if self.is_torgb else 0.2
x = filtered_lrelu.filtered_lrelu(x=x, fu=self.up_filter, fd=self.down_filter, b=self.bias.to(x.dtype),
up=self.up_factor, down=self.down_factor, padding=self.padding, gain=gain, slope=slope, clamp=self.conv_clamp)
# Ensure correct shape and dtype.
misc.assert_shape(x, [None, self.out_channels, int(self.out_size[1]), int(self.out_size[0])])
assert x.dtype == dtype
return x
@staticmethod
def design_lowpass_filter(numtaps, cutoff, width, fs, radial=False):
assert numtaps >= 1
# Identity filter.
if numtaps == 1:
return None
# Separable Kaiser low-pass filter.
if not radial:
f = scipy.signal.firwin(numtaps=numtaps, cutoff=cutoff, width=width, fs=fs)
return torch.as_tensor(f, dtype=torch.float32)
# Radially symmetric jinc-based filter.
x = (np.arange(numtaps) - (numtaps - 1) / 2) / fs
r = np.hypot(*np.meshgrid(x, x))
f = scipy.special.j1(2 * cutoff * (np.pi * r)) / (np.pi * r)
beta = scipy.signal.kaiser_beta(scipy.signal.kaiser_atten(numtaps, width / (fs / 2)))
w = np.kaiser(numtaps, beta)
f *= np.outer(w, w)
f /= np.sum(f)
return torch.as_tensor(f, dtype=torch.float32)
def extra_repr(self):
return '\n'.join([
f'w_dim={self.w_dim:d}, is_torgb={self.is_torgb},',
f'is_critically_sampled={self.is_critically_sampled}, use_fp16={self.use_fp16},',
f'in_sampling_rate={self.in_sampling_rate:g}, out_sampling_rate={self.out_sampling_rate:g},',
f'in_cutoff={self.in_cutoff:g}, out_cutoff={self.out_cutoff:g},',
f'in_half_width={self.in_half_width:g}, out_half_width={self.out_half_width:g},',
f'in_size={list(self.in_size)}, out_size={list(self.out_size)},',
f'in_channels={self.in_channels:d}, out_channels={self.out_channels:d}'])
#----------------------------------------------------------------------------
@persistence.persistent_class
class ToRGBLayer(torch.nn.Module):
def __init__(self, in_channels, out_channels, w_dim=0, kernel_size=1, conv_clamp=None, channels_last=False, mode='2d', **unused):
super().__init__()
self.conv_clamp = conv_clamp
self.mode = mode
weight_shape = [out_channels, in_channels, kernel_size, kernel_size]
if mode == '3d':
weight_shape += [kernel_size]
if w_dim > 0:
self.affine = FullyConnectedLayer(w_dim, in_channels, bias_init=1)
memory_format = torch.channels_last if channels_last else torch.contiguous_format
self.weight = torch.nn.Parameter(torch.randn(weight_shape).to(memory_format=memory_format))
self.bias = torch.nn.Parameter(torch.zeros([out_channels]))
self.weight_gain = 1 / np.sqrt(np.prod(weight_shape[1:]))
else:
assert kernel_size == 1, "does not support larger kernel sizes for now. used in NeRF"
assert mode != '3d', "does not support 3D convolution for now"
self.weight = torch.nn.Parameter(torch.Tensor(out_channels, in_channels))
self.bias = torch.nn.Parameter(torch.Tensor(out_channels))
self.weight_gain = 1.
# initialization
torch.nn.init.kaiming_uniform_(self.weight, a=math.sqrt(5))
fan_in, _ = torch.nn.init._calculate_fan_in_and_fan_out(self.weight)
bound = 1 / math.sqrt(fan_in)
torch.nn.init.uniform_(self.bias, -bound, bound)
def forward(self, x, w=None, fused_modconv=True):
if w is not None:
styles = self.affine(w) * self.weight_gain
if x.size(0) > styles.size(0):
assert (x.size(0) // styles.size(0) * styles.size(0) == x.size(0))
styles = repeat(styles, 'b c -> (b s) c', s=x.size(0) // styles.size(0))
x = modulated_conv2d(x=x, weight=self.weight, styles=styles, demodulate=False, fused_modconv=fused_modconv, mode=self.mode)
x = bias_act.bias_act(x, self.bias.to(x.dtype), clamp=self.conv_clamp)
else:
if x.ndim == 2:
x = F.linear(x, self.weight, self.bias)
else:
x = F.conv2d(x, self.weight[:,:,None,None], self.bias)
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class SynthesisBlock(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels, 0 = first block.
out_channels, # Number of output channels.
w_dim, # Intermediate latent (W) dimensionality.
resolution, # Resolution of this block.
img_channels, # Number of output color channels.
is_last, # Is this the last block?
architecture = 'skip', # Architecture: 'orig', 'skip', 'resnet'.
resample_filter = [1,3,3,1], # Low-pass filter to apply when resampling activations.
conv_clamp = None, # Clamp the output of convolution layers to +-X, None = disable clamping.
use_fp16 = False, # Use FP16 for this block?
fp16_channels_last = False, # Use channels-last memory format with FP16?
use_single_layer = False, # use only one instead of two synthesis layer
disable_upsample = False,
**layer_kwargs, # Arguments for SynthesisLayer.
):
assert architecture in ['orig', 'skip', 'resnet']
super().__init__()
self.in_channels = in_channels
self.out_channels = out_channels
self.w_dim = w_dim
self.resolution = resolution
self.img_channels = img_channels
self.is_last = is_last
self.architecture = architecture
self.use_fp16 = use_fp16
self.channels_last = (use_fp16 and fp16_channels_last)
self.register_buffer('resample_filter', upfirdn2d.setup_filter(resample_filter))
self.num_conv = 0
self.num_torgb = 0
self.groups = 1
self.use_single_layer = use_single_layer
self.margin = layer_kwargs.get('margin', 0)
self.upsample_mode = layer_kwargs.get('upsample_mode', 'default')
self.disable_upsample = disable_upsample
self.mode = layer_kwargs.get('mode', '2d')
if in_channels == 0:
const_sizes = [out_channels, resolution, resolution]
if self.mode == '3d':
const_sizes = const_sizes + [resolution]
self.const = torch.nn.Parameter(torch.randn(const_sizes))
if in_channels != 0:
self.conv0 = util.construct_class_by_name(
class_name=layer_kwargs.get('layer_name', "training.networks.SynthesisLayer"),
in_channels=in_channels, out_channels=out_channels,
w_dim=w_dim, resolution=resolution,
up=2 if (not disable_upsample) else 1,
resample_filter=resample_filter, conv_clamp=conv_clamp,
channels_last=self.channels_last, **layer_kwargs)
self.num_conv += 1
if not self.use_single_layer:
self.conv1 = util.construct_class_by_name(
class_name=layer_kwargs.get('layer_name', "training.networks.SynthesisLayer"),
in_channels=out_channels, out_channels=out_channels,
w_dim=w_dim, resolution=resolution,
conv_clamp=conv_clamp, channels_last=self.channels_last, **layer_kwargs)
self.num_conv += 1
if is_last or architecture == 'skip':
self.torgb = ToRGBLayer(
out_channels, img_channels, w_dim=w_dim,
conv_clamp=conv_clamp, channels_last=self.channels_last,
groups=self.groups, mode=self.mode)
self.num_torgb += 1
if in_channels != 0 and architecture == 'resnet':
self.skip = Conv2dLayer(
in_channels, out_channels, kernel_size=1, bias=False, up=2,
resample_filter=resample_filter,
channels_last=self.channels_last,
mode=self.mode)
def forward(self, x, img, ws, force_fp32=False, fused_modconv=None, add_on=None, block_noise=None, disable_rgb=False, **layer_kwargs):
misc.assert_shape(ws, [None, self.num_conv + self.num_torgb, self.w_dim])
w_iter = iter(ws.unbind(dim=1))
dtype = torch.float16 if (self.use_fp16 and x.device.type == 'cuda') and not force_fp32 else torch.float32
memory_format = torch.channels_last if self.channels_last and not force_fp32 else torch.contiguous_format
if fused_modconv is None:
with misc.suppress_tracer_warnings(): # this value will be treated as a constant
fused_modconv = (not self.training) and (dtype == torch.float32 or int(x.shape[0]) == 1)
# Input.
if self.in_channels == 0:
x = self.const.to(dtype=dtype, memory_format=memory_format)
x = x.unsqueeze(0).expand(ws.shape[0], *x.size())
else:
x = x.to(dtype=dtype, memory_format=memory_format)
# Main layers.
if add_on is not None:
add_on = add_on.to(dtype=dtype, memory_format=memory_format)
if self.in_channels == 0:
if not self.use_single_layer:
layer_kwargs['input_noise'] = block_noise[:,1:2] if block_noise is not None else None
x = self.conv1(x, next(w_iter), fused_modconv=fused_modconv, **layer_kwargs)
elif self.architecture == 'resnet':
y = self.skip(x, gain=np.sqrt(0.5))
layer_kwargs['input_noise'] = block_noise[:,0:1] if block_noise is not None else None
x = self.conv0(x, next(w_iter), fused_modconv=fused_modconv, **layer_kwargs)
if not self.use_single_layer:
layer_kwargs['input_noise'] = block_noise[:,1:2] if block_noise is not None else None
x = self.conv1(x, next(w_iter), fused_modconv=fused_modconv, gain=np.sqrt(0.5), **layer_kwargs)
x = y.add_(x)
else:
layer_kwargs['input_noise'] = block_noise[:,0:1] if block_noise is not None else None
x = self.conv0(x, next(w_iter), fused_modconv=fused_modconv, **layer_kwargs)
if not self.use_single_layer:
layer_kwargs['input_noise'] = block_noise[:,1:2] if block_noise is not None else None
x = self.conv1(x, next(w_iter), fused_modconv=fused_modconv, **layer_kwargs)
# ToRGB.
if img is not None:
if img.size(-1) * 2 == x.size(-1):
if (self.upsample_mode == 'bilinear_all') or (self.upsample_mode == 'bilinear_ada'):
img = F.interpolate(img, scale_factor=2, mode='bilinear', align_corners=True)
else:
img = upfirdn2d.upsample2d(img, self.resample_filter) # this is upsampling. Not sure about details and why they do this..
elif img.size(-1) == x.size(-1):
pass
else:
raise NotImplementedError
if self.is_last or self.architecture == 'skip':
if not disable_rgb:
y = x if add_on is None else x + add_on
y = self.torgb(y, next(w_iter), fused_modconv=fused_modconv)
y = y.to(dtype=torch.float32, memory_format=torch.contiguous_format)
img = img.add_(y) if img is not None else y
else:
img = None
assert x.dtype == dtype
assert img is None or img.dtype == torch.float32
return x, img
#----------------------------------------------------------------------------
@persistence.persistent_class
class SynthesisBlock3(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels, 0 = first block.
out_channels, # Number of output channels.
w_dim, # Intermediate latent (W) dimensionality.
resolution, # Resolution of this block.
img_channels, # Number of output color channels.
block_id,
stylegan3_hyperam,
use_fp16 = False, # Use FP16 for this block?
**layer_kwargs, # Arguments for SynthesisLayer.
):
super().__init__()
self.in_channels = in_channels
self.out_channels = out_channels
self.w_dim = w_dim
self.resolution = resolution
self.img_channels = img_channels
self.num_conv = 0
self.num_torgb = 0
self.use_fp16 = use_fp16
is_critically_sampled = block_id == (len(stylegan3_hyperam['sampling_rates'][:-1]) // 2 - 1)
sizes, sampling_rates, cutoffs, half_widths = \
stylegan3_hyperam['sizes'], stylegan3_hyperam['sampling_rates'], \
stylegan3_hyperam['cutoffs'], stylegan3_hyperam['half_widths']
# each block has two layer
prev = max(block_id * 2 - 1, 0)
curr = block_id * 2
self.conv0 = util.construct_class_by_name(
class_name=layer_kwargs.get('layer_name', "training.networks.SynthesisLayer3"),
w_dim=self.w_dim,
is_torgb=False,
is_critically_sampled=is_critically_sampled,
use_fp16=use_fp16,
in_channels=in_channels,
out_channels=out_channels,
in_size=int(sizes[prev]),
out_size=int(sizes[curr]),
in_sampling_rate=int(sampling_rates[prev]),
out_sampling_rate=int(sampling_rates[curr]),
in_cutoff=cutoffs[prev],
out_cutoff=cutoffs[curr],
in_half_width=half_widths[prev],
out_half_width=half_widths[curr],
use_radial_filters=True,
**layer_kwargs)
self.num_conv += 1
prev = block_id * 2
curr = block_id * 2 + 1
self.conv1 = util.construct_class_by_name(
class_name=layer_kwargs.get('layer_name', "training.networks.SynthesisLayer3"),
w_dim=self.w_dim,
is_torgb=False,
is_critically_sampled=is_critically_sampled,
use_fp16=use_fp16,
in_channels=out_channels,
out_channels=out_channels,
in_size=int(sizes[prev]),
out_size=int(sizes[curr]),
in_sampling_rate=int(sampling_rates[prev]),
out_sampling_rate=int(sampling_rates[curr]),
in_cutoff=cutoffs[prev],
out_cutoff=cutoffs[curr],
in_half_width=half_widths[prev],
out_half_width=half_widths[curr],
use_radial_filters=True,
**layer_kwargs)
self.num_conv += 1
# toRGB layer (used for progressive growing)
self.torgb = ToRGBLayer(out_channels, img_channels, w_dim=w_dim)
self.num_torgb += 1
def forward(self, x, img, ws, force_fp32=False, add_on=None, disable_rgb=False, **layer_kwargs):
w_iter = iter(ws.unbind(dim=1))
dtype = torch.float16 if (self.use_fp16 and x.device.type == 'cuda') and not force_fp32 else torch.float32
memory_format = torch.contiguous_format
# Main layers.
x = x.to(dtype=dtype, memory_format=memory_format)
if add_on is not None:
add_on = add_on.to(dtype=dtype, memory_format=memory_format)
x = self.conv0(x, next(w_iter), **layer_kwargs)
x = self.conv1(x, next(w_iter), **layer_kwargs)
assert img is None, "currently not support."
if not disable_rgb:
y = x if add_on is None else x + add_on
y = self.torgb(y, next(w_iter), fused_modconv=True)
y = y.to(dtype=torch.float32, memory_format=torch.contiguous_format)
img = y
assert x.dtype == dtype
assert img is None or img.dtype == torch.float32
return x, img
#----------------------------------------------------------------------------
@persistence.persistent_class
class SynthesisNetwork(torch.nn.Module):
def __init__(self,
w_dim, # Intermediate latent (W) dimensionality.
img_resolution, # Output image resolution.
img_channels, # Number of color channels.
channel_base = 1, # Overall multiplier for the number of channels.
channel_max = 512, # Maximum number of channels in any layer.
num_fp16_res = 0, # Use FP16 for the N highest resolutions.
**block_kwargs, # Arguments for SynthesisBlock.
):
assert img_resolution >= 4 and img_resolution & (img_resolution - 1) == 0
super().__init__()
self.w_dim = w_dim
self.img_resolution = img_resolution
self.img_resolution_log2 = int(np.log2(img_resolution))
self.img_channels = img_channels
self.block_resolutions = [2 ** i for i in range(2, self.img_resolution_log2 + 1)]
channel_base = int(channel_base * 32768)
channels_dict = {res: min(channel_base // res, channel_max) for res in self.block_resolutions}
fp16_resolution = max(2 ** (self.img_resolution_log2 + 1 - num_fp16_res), 8)
self.channels_dict = channels_dict
self.num_ws = 0
for res in self.block_resolutions:
in_channels = channels_dict[res // 2] if res > 4 else 0
out_channels = channels_dict[res]
use_fp16 = (res >= fp16_resolution)
is_last = (res == self.img_resolution)
block = util.construct_class_by_name(
class_name=block_kwargs.get('block_name', "training.networks.SynthesisBlock"),
in_channels=in_channels, out_channels=out_channels, w_dim=w_dim, resolution=res,
img_channels=img_channels, is_last=is_last, use_fp16=use_fp16, **block_kwargs)
self.num_ws += block.num_conv
if is_last:
self.num_ws += block.num_torgb
setattr(self, f'b{res}', block)
def forward(self, ws, **block_kwargs):
block_ws = []
# this part is to slice the style matrices (W) to each layer (conv/RGB)
with torch.autograd.profiler.record_function('split_ws'):
misc.assert_shape(ws, [None, self.num_ws, self.w_dim])
ws = ws.to(torch.float32)
w_idx = 0
for res in self.block_resolutions:
block = getattr(self, f'b{res}')
block_ws.append(ws.narrow(1, w_idx, block.num_conv + block.num_torgb))
w_idx += block.num_conv
x = img = None
for res, cur_ws in zip(self.block_resolutions, block_ws):
block = getattr(self, f'b{res}')
x, img = block(x, img, cur_ws, **block_kwargs)
return img
def get_current_resolution(self):
return [self.img_resolution] # For compitibility
#----------------------------------------------------------------------------
@persistence.persistent_class
class Generator(torch.nn.Module):
def __init__(self,
z_dim, # Input latent (Z) dimensionality.
c_dim, # Conditioning label (C) dimensionality.
w_dim, # Intermediate latent (W) dimensionality.
img_resolution, # Output resolution.
img_channels, # Number of output color channels.
mapping_kwargs = {}, # Arguments for MappingNetwork.
synthesis_kwargs = {}, # Arguments for SynthesisNetwork.
encoder_kwargs = {}, # Arguments for Encoder (optional)
):
super().__init__()
self.z_dim = z_dim
self.c_dim = c_dim
self.w_dim = w_dim
self.img_resolution = img_resolution
self.img_channels = img_channels
self.synthesis = util.construct_class_by_name(
class_name=synthesis_kwargs.get('module_name', "training.networks.SynthesisNetwork"),
w_dim=w_dim, img_resolution=img_resolution, img_channels=img_channels, **synthesis_kwargs)
self.num_ws = self.synthesis.num_ws
self.mapping = None
self.encoder = None
if len(mapping_kwargs) > 0: # Use mapping network
self.mapping = util.construct_class_by_name(
class_name=mapping_kwargs.get('module_name', "training.networks.MappingNetwork"),
z_dim=z_dim, c_dim=c_dim, w_dim=w_dim, num_ws=self.num_ws, **mapping_kwargs)
if len(encoder_kwargs) > 0: # Use Image-Encoder
encoder_kwargs['model_kwargs'].update({'num_ws': self.num_ws, 'w_dim': self.w_dim})
self.encoder = util.construct_class_by_name(
img_resolution=img_resolution,
img_channels=img_channels,
**encoder_kwargs)
def forward(self, z=None, c=None, styles=None, truncation_psi=1, truncation_cutoff=None, img=None, **synthesis_kwargs):
if styles is None:
assert z is not None
if (self.encoder is not None) and (img is not None): #TODO: debug
outputs = self.encoder(img)
ws = outputs['ws']
if ('camera' in outputs) and ('camera_mode' not in synthesis_kwargs):
synthesis_kwargs['camera_RT'] = outputs['camera']
else:
ws = self.mapping(z, c, truncation_psi=truncation_psi, truncation_cutoff=truncation_cutoff, **synthesis_kwargs)
else:
ws = styles
img = self.synthesis(ws, **synthesis_kwargs)
return img
def get_final_output(self, *args, **kwargs):
img = self.forward(*args, **kwargs)
if isinstance(img, list):
return img[-1]
elif isinstance(img, dict):
return img['img']
return img
#----------------------------------------------------------------------------
@persistence.persistent_class
class DiscriminatorBlock(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels, 0 = first block.
tmp_channels, # Number of intermediate channels.
out_channels, # Number of output channels.
resolution, # Resolution of this block.
img_channels, # Number of input color channels.
first_layer_idx, # Index of the first layer.
architecture = 'resnet', # Architecture: 'orig', 'skip', 'resnet'.
activation = 'lrelu', # Activation function: 'relu', 'lrelu', etc.
resample_filter = [1,3,3,1], # Low-pass filter to apply when resampling activations.
conv_clamp = None, # Clamp the output of convolution layers to +-X, None = disable clamping.
use_fp16 = False, # Use FP16 for this block?
fp16_channels_last = False, # Use channels-last memory format with FP16?
freeze_layers = 0, # Freeze-D: Number of layers to freeze.
):
assert in_channels in [0, tmp_channels]
assert architecture in ['orig', 'skip', 'resnet']
super().__init__()
self.in_channels = in_channels
self.resolution = resolution
self.img_channels = img_channels
self.first_layer_idx = first_layer_idx
self.architecture = architecture
self.use_fp16 = use_fp16
self.channels_last = (use_fp16 and fp16_channels_last)
self.register_buffer('resample_filter', upfirdn2d.setup_filter(resample_filter))
self.num_layers = 0
def trainable_gen():
while True:
layer_idx = self.first_layer_idx + self.num_layers
trainable = (layer_idx >= freeze_layers)
self.num_layers += 1
yield trainable
trainable_iter = trainable_gen()
if in_channels == 0 or architecture == 'skip':
self.fromrgb = Conv2dLayer(img_channels, tmp_channels, kernel_size=1, activation=activation,
trainable=next(trainable_iter), conv_clamp=conv_clamp, channels_last=self.channels_last)
self.conv0 = Conv2dLayer(tmp_channels, tmp_channels, kernel_size=3, activation=activation,
trainable=next(trainable_iter), conv_clamp=conv_clamp, channels_last=self.channels_last)
self.conv1 = Conv2dLayer(tmp_channels, out_channels, kernel_size=3, activation=activation, down=2,
trainable=next(trainable_iter), resample_filter=resample_filter, conv_clamp=conv_clamp, channels_last=self.channels_last)
if architecture == 'resnet':
self.skip = Conv2dLayer(tmp_channels, out_channels, kernel_size=1, bias=False, down=2,
trainable=next(trainable_iter), resample_filter=resample_filter, channels_last=self.channels_last)
def forward(self, x, img, force_fp32=False, downsampler=None):
dtype = torch.float16 if (self.use_fp16 and x.device.type == 'cuda') and not force_fp32 else torch.float32
memory_format = torch.channels_last if self.channels_last and not force_fp32 else torch.contiguous_format
# Input.
if x is not None:
misc.assert_shape(x, [None, self.in_channels, self.resolution, self.resolution])
x = x.to(dtype=dtype, memory_format=memory_format)
# FromRGB.
if self.in_channels == 0 or self.architecture == 'skip':
misc.assert_shape(img, [None, self.img_channels, self.resolution, self.resolution])
img = img.to(dtype=dtype, memory_format=memory_format)
y = self.fromrgb(img)
x = x + y if x is not None else y
if self.architecture != 'skip':
img = None
elif downsampler is not None:
img = downsampler(img, 2)
else:
img = upfirdn2d.downsample2d(img, self.resample_filter)
# Main layers.
if self.architecture == 'resnet':
y = self.skip(x, gain=np.sqrt(0.5))
x = self.conv0(x)
x = self.conv1(x, gain=np.sqrt(0.5))
x = y.add_(x)
else:
x = self.conv0(x)
x = self.conv1(x)
assert x.dtype == dtype
return x, img
#----------------------------------------------------------------------------
@persistence.persistent_class
class MinibatchStdLayer(torch.nn.Module):
def __init__(self, group_size, num_channels=1):
super().__init__()
self.group_size = group_size
self.num_channels = num_channels
def forward(self, x):
N, C, H, W = x.shape
with misc.suppress_tracer_warnings(): # as_tensor results are registered as constants
G = torch.min(torch.as_tensor(self.group_size), torch.as_tensor(N)) if self.group_size is not None else N
F = self.num_channels
c = C // F
y = x.reshape(G, -1, F, c, H, W) # [GnFcHW] Split minibatch N into n groups of size G, and channels C into F groups of size c.
y = y - y.mean(dim=0) # [GnFcHW] Subtract mean over group.
y = y.square().mean(dim=0) # [nFcHW] Calc variance over group.
y = (y + 1e-8).sqrt() # [nFcHW] Calc stddev over group.
y = y.mean(dim=[2,3,4]) # [nF] Take average over channels and pixels.
y = y.reshape(-1, F, 1, 1) # [nF11] Add missing dimensions.
y = y.repeat(G, 1, H, W) # [NFHW] Replicate over group and pixels.
x = torch.cat([x, y], dim=1) # [NCHW] Append to input as new channels.
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class DiscriminatorEpilogue(torch.nn.Module):
def __init__(self,
in_channels, # Number of input channels.
cmap_dim, # Dimensionality of mapped conditioning label, 0 = no label.
resolution, # Resolution of this block.
img_channels, # Number of input color channels.
architecture = 'resnet', # Architecture: 'orig', 'skip', 'resnet'.
mbstd_group_size = 4, # Group size for the minibatch standard deviation layer, None = entire minibatch.
mbstd_num_channels = 1, # Number of features for the minibatch standard deviation layer, 0 = disable.
activation = 'lrelu', # Activation function: 'relu', 'lrelu', etc.
conv_clamp = None, # Clamp the output of convolution layers to +-X, None = disable clamping.
final_channels = 1, # for classification it is always 1.
):
assert architecture in ['orig', 'skip', 'resnet']
super().__init__()
self.in_channels = in_channels
self.final_channels = final_channels
self.cmap_dim = cmap_dim
self.resolution = resolution
self.img_channels = img_channels
self.architecture = architecture
if architecture == 'skip':
self.fromrgb = Conv2dLayer(img_channels, in_channels, kernel_size=1, activation=activation)
self.mbstd = MinibatchStdLayer(group_size=mbstd_group_size, num_channels=mbstd_num_channels) if mbstd_num_channels > 0 else None
self.conv = Conv2dLayer(in_channels + mbstd_num_channels, in_channels, kernel_size=3, activation=activation, conv_clamp=conv_clamp)
self.fc = FullyConnectedLayer(in_channels * (resolution ** 2), in_channels, activation=activation)
self.out = FullyConnectedLayer(in_channels, final_channels if cmap_dim == 0 else cmap_dim)
def forward(self, x, img, cmap, force_fp32=False):
misc.assert_shape(x, [None, self.in_channels, self.resolution, self.resolution]) # [NCHW]
_ = force_fp32 # unused
dtype = torch.float32
memory_format = torch.contiguous_format
# FromRGB.
x = x.to(dtype=dtype, memory_format=memory_format)
if self.architecture == 'skip':
misc.assert_shape(img, [None, self.img_channels, self.resolution, self.resolution])
img = img.to(dtype=dtype, memory_format=memory_format)
x = x + self.fromrgb(img)
# Main layers.
if self.mbstd is not None:
x = self.mbstd(x)
x = self.conv(x)
x = self.fc(x.flatten(1))
x = self.out(x)
# Conditioning.
if self.cmap_dim > 0:
if not isinstance(cmap, list):
cmap = [cmap] # in case of multiple conditions. a trick (TODO)
x = [(x * c).sum(dim=1, keepdim=True) * (1 / np.sqrt(self.cmap_dim)) for c in cmap]
x = sum(x) / len(cmap)
assert x.dtype == dtype
return x
#----------------------------------------------------------------------------
@persistence.persistent_class
class Discriminator(torch.nn.Module): # The original StyleGAN2 discriminator
def __init__(self,
c_dim, # Conditioning label (C) dimensionality.
img_resolution, # Input resolution.
img_channels, # Number of input color channels.
architecture = 'resnet', # Architecture: 'orig', 'skip', 'resnet'.
channel_base = 32768, # Overall multiplier for the number of channels.
channel_max = 512, # Maximum number of channels in any layer.
num_fp16_res = 0, # Use FP16 for the N highest resolutions.
conv_clamp = None, # Clamp the output of convolution layers to +-X, None = disable clamping.
cmap_dim = None, # Dimensionality of mapped conditioning label, None = default.
block_kwargs = {}, # Arguments for DiscriminatorBlock.
mapping_kwargs = {}, # Arguments for MappingNetwork.
epilogue_kwargs = {}, # Arguments for DiscriminatorEpilogue.
):
super().__init__()
self.c_dim = c_dim
self.img_resolution = img_resolution
self.img_resolution_log2 = int(np.log2(img_resolution))
self.img_channels = img_channels
self.block_resolutions = [2 ** i for i in range(self.img_resolution_log2, 2, -1)]
channels_dict = {res: min(channel_base // res, channel_max) for res in self.block_resolutions + [4]}
fp16_resolution = max(2 ** (self.img_resolution_log2 + 1 - num_fp16_res), 8)
if cmap_dim is None:
cmap_dim = channels_dict[4]
if c_dim == 0:
cmap_dim = 0
common_kwargs = dict(img_channels=img_channels, architecture=architecture, conv_clamp=conv_clamp)
cur_layer_idx = 0
for res in self.block_resolutions:
in_channels = channels_dict[res] if res < img_resolution else 0
tmp_channels = channels_dict[res]
out_channels = channels_dict[res // 2]
use_fp16 = (res >= fp16_resolution)
block = DiscriminatorBlock(in_channels, tmp_channels, out_channels, resolution=res,
first_layer_idx=cur_layer_idx, use_fp16=use_fp16, **block_kwargs, **common_kwargs)
setattr(self, f'b{res}', block)
cur_layer_idx += block.num_layers
if c_dim > 0:
self.mapping = MappingNetwork(z_dim=0, c_dim=c_dim, w_dim=cmap_dim, num_ws=None, w_avg_beta=None, **mapping_kwargs)
self.b4 = DiscriminatorEpilogue(channels_dict[4], cmap_dim=cmap_dim, resolution=4, **epilogue_kwargs, **common_kwargs)
def forward(self, img, c, **block_kwargs):
x = None
if isinstance(img, dict):
img = img['img']
for res in self.block_resolutions:
block = getattr(self, f'b{res}')
x, img = block(x, img, **block_kwargs)
cmap = None
if self.c_dim > 0:
cmap = self.mapping(None, c)
x = self.b4(x, img, cmap)
return x
#----------------------------------------------------------------------------
# encoders maybe used for inversion (not cleaned)
@persistence.persistent_class
class EncoderResBlock(torch.nn.Module):
def __init__(self, in_channel, out_channel, blur_kernel=[1, 3, 3, 1]):
super().__init__()
self.conv1 = Conv2dLayer(in_channel, in_channel, 3, activation='lrelu')
self.conv2 = Conv2dLayer(in_channel, out_channel, 3, down=2, activation='lrelu')
self.skip = Conv2dLayer(in_channel, out_channel, 1, down=2, activation='linear', bias=False)
def forward(self, input):
out = self.conv1(input)
out = self.conv2(out)
skip = self.skip(input)
out = (out + skip) / math.sqrt(2)
return out
@persistence.persistent_class
class EqualConv2d(torch.nn.Module):
def __init__(
self, in_channel, out_channel, kernel_size, stride=1, padding=0, bias=True
):
super().__init__()
new_scale = 1.0
self.weight = torch.nn.Parameter(
torch.randn(out_channel, in_channel, kernel_size, kernel_size) * new_scale
)
self.scale = 1 / math.sqrt(in_channel * kernel_size ** 2)
self.stride = stride
self.padding = padding
if bias:
self.bias = torch.nn.Parameter(torch.zeros(out_channel))
else:
self.bias = None
def forward(self, input):
out = F.conv2d(
input,
self.weight * self.scale,
bias=self.bias,
stride=self.stride,
padding=self.padding,
)
return out
def __repr__(self):
return (
f'{self.__class__.__name__}({self.weight.shape[1]}, {self.weight.shape[0]},'
f' {self.weight.shape[2]}, stride={self.stride}, padding={self.padding})'
)
@persistence.persistent_class
class Encoder(torch.nn.Module):
def __init__(self, size, n_latents, w_dim=512, add_dim=0, **unused):
super().__init__()
channels = {
4: 512,
8: 512,
16: 512,
32: 512,
64: 256,
128: 128,
256: 64,
512: 32,
1024: 16
}
self.w_dim = w_dim
self.add_dim = add_dim
log_size = int(math.log(size, 2))
self.n_latents = n_latents
convs = [Conv2dLayer(3, channels[size], 1)]
in_channel = channels[size]
for i in range(log_size, 2, -1):
out_channel = channels[2 ** (i - 1)]
convs.append(EncoderResBlock(in_channel, out_channel))
in_channel = out_channel
self.convs = torch.nn.Sequential(*convs)
self.projector = EqualConv2d(in_channel, self.n_latents*self.w_dim + add_dim, 4, padding=0, bias=False)
def forward(self, input):
out = self.convs(input)
out = self.projector(out)
pws, pcm = out[:, :-2], out[:, -2:]
pws = pws.view(len(input), self.n_latents, self.w_dim)
pcm = pcm.view(len(input), self.add_dim)
return pws, pcm
@persistence.persistent_class
class ResNetEncoder(torch.nn.Module):
def __init__(self):
super().__init__()
import torchvision
resnet_net = torchvision.models.resnet18(pretrained=True)
modules = list(resnet_net.children())[:-1]
self.convs = torch.nn.Sequential(*modules)
self.requires_grad_(True)
self.train()
def preprocess_tensor(self, x):
x = F.interpolate(x, size=(224, 224), mode='bicubic', align_corners=False)
return x
def forward(self, input):
out = self.convs(self.preprocess_tensor(input))
return out[:, :, 0, 0]
@persistence.persistent_class
class CLIPEncoder(torch.nn.Module):
def __init__(self):
super().__init__()
import clip
clip_net, _ = clip.load('ViT-B/32', device='cpu', jit=False)
self.encoder = clip_net.visual
for p in self.encoder.parameters():
p.requires_grad_(True)
def preprocess_tensor(self, x):
import PIL.Image
import torchvision.transforms.functional as TF
x = x * 0.5 + 0.5 # mapping to 0~1
x = TF.resize(x, size=224, interpolation=PIL.Image.BICUBIC)
x = TF.normalize(x, (0.48145466, 0.4578275, 0.40821073), (0.26862954, 0.26130258, 0.27577711))
return x
def forward(self, input):
out = self.encoder(self.preprocess_tensor(input))
return out
# --------------------------------------------------------------------------------------------------- #
# VolumeGAN thanks https://gist.github.com/justimyhxu/a96f5ac25480d733f3151adb8142d706
@persistence.persistent_class
class InstanceNormLayer3d(torch.nn.Module):
"""Implements instance normalization layer."""
def __init__(self, num_features, epsilon=1e-8, affine=False):
super().__init__()
self.eps = epsilon
self.affine = affine
if self.affine:
self.weight = torch.nn.Parameter(torch.Tensor(1, num_features,1,1,1))
self.bias = torch.nn.Parameter(torch.Tensor(1, num_features,1,1,1))
self.weight.data.uniform_()
self.bias.data.zero_()
def forward(self, x, weight=None, bias=None):
x = x - torch.mean(x, dim=[2, 3, 4], keepdim=True)
norm = torch.sqrt(
torch.mean(x**2, dim=[2, 3, 4], keepdim=True) + self.eps)
x = x / norm
isnot_input_none = weight is not None and bias is not None
assert (isnot_input_none and not self.affine) or (not isnot_input_none and self.affine)
if self.affine:
x = x*self.weight + self.bias
else:
x = x*weight + bias
return x
@persistence.persistent_class
class FeatureVolume(torch.nn.Module):
def __init__(
self,
feat_res=32,
init_res=4,
base_channels=256,
output_channels=32,
z_dim=256,
use_mapping=True,
**kwargs
):
super().__init__()
self.num_stages = int(np.log2(feat_res // init_res)) + 1
self.use_mapping = use_mapping
self.const = nn.Parameter(
torch.ones(1, base_channels, init_res, init_res, init_res))
inplanes = base_channels
outplanes = base_channels
self.stage_channels = []
for i in range(self.num_stages):
conv = nn.Conv3d(inplanes,
outplanes,
kernel_size=(3, 3, 3),
padding=(1, 1, 1))
self.stage_channels.append(outplanes)
self.add_module(f'layer{i}', conv)
instance_norm = InstanceNormLayer3d(num_features=outplanes, affine=not use_mapping)
self.add_module(f'instance_norm{i}', instance_norm)
inplanes = outplanes
outplanes = max(outplanes // 2, output_channels)
if i == self.num_stages - 1:
outplanes = output_channels
if self.use_mapping:
self.mapping_network = CustomMappingNetwork(
z_dim, 256,
sum(self.stage_channels) * 2)
self.upsample = UpsamplingLayer()
self.lrelu = nn.LeakyReLU(negative_slope=0.2)
def forward(self, z, **kwargs):
if self.use_mapping:
scales, shifts, style = self.mapping_network(z)
x = self.const.repeat(z.shape[0], 1, 1, 1, 1)
for idx in range(self.num_stages):
if idx != 0:
x = self.upsample(x)
conv_layer = self.__getattr__(f'layer{idx}')
x = conv_layer(x)
instance_norm = self.__getattr__(f'instance_norm{idx}')
if self.use_mapping:
scale = scales[:, sum(self.stage_channels[:idx]):sum(self.stage_channels[:idx + 1])]
shift = shifts[:, sum(self.stage_channels[:idx]):sum(self.stage_channels[:idx + 1])]
scale = scale.view(scale.shape + (1, 1, 1))
shift = shift.view(shift.shape + (1, 1, 1))
else:
scale, shift = None, None
x = instance_norm(x, weight=scale, bias=shift)
x = self.lrelu(x)
return x