Files
2024-08-10 19:39:39 +07:00

223 lines
7.8 KiB
Python

import numpy as np
import torch
import torch.nn.functional as F
from torch import nn
from torchvision import models
from .util import TPS, AntiAliasInterpolation2d
class Vgg19(torch.nn.Module):
"""
Vgg19 network for perceptual loss. See Sec 3.3.
"""
def __init__(self, requires_grad=False):
super(Vgg19, self).__init__()
vgg_pretrained_features = models.vgg19(pretrained=True).features
self.slice1 = torch.nn.Sequential()
self.slice2 = torch.nn.Sequential()
self.slice3 = torch.nn.Sequential()
self.slice4 = torch.nn.Sequential()
self.slice5 = torch.nn.Sequential()
for x in range(2):
self.slice1.add_module(str(x), vgg_pretrained_features[x])
for x in range(2, 7):
self.slice2.add_module(str(x), vgg_pretrained_features[x])
for x in range(7, 12):
self.slice3.add_module(str(x), vgg_pretrained_features[x])
for x in range(12, 21):
self.slice4.add_module(str(x), vgg_pretrained_features[x])
for x in range(21, 30):
self.slice5.add_module(str(x), vgg_pretrained_features[x])
self.mean = torch.nn.Parameter(
data=torch.Tensor(np.array([0.485, 0.456, 0.406]).reshape((1, 3, 1, 1))),
requires_grad=False,
)
self.std = torch.nn.Parameter(
data=torch.Tensor(np.array([0.229, 0.224, 0.225]).reshape((1, 3, 1, 1))),
requires_grad=False,
)
if not requires_grad:
for param in self.parameters():
param.requires_grad = False
def forward(self, X):
X = (X - self.mean) / self.std
h_relu1 = self.slice1(X)
h_relu2 = self.slice2(h_relu1)
h_relu3 = self.slice3(h_relu2)
h_relu4 = self.slice4(h_relu3)
h_relu5 = self.slice5(h_relu4)
out = [h_relu1, h_relu2, h_relu3, h_relu4, h_relu5]
return out
class ImagePyramide(torch.nn.Module):
"""
Create image pyramide for computing pyramide perceptual loss. See Sec 3.3
"""
def __init__(self, scales, num_channels):
super(ImagePyramide, self).__init__()
downs = {}
for scale in scales:
downs[str(scale).replace(".", "-")] = AntiAliasInterpolation2d(
num_channels, scale
)
self.downs = nn.ModuleDict(downs)
def forward(self, x):
out_dict = {}
for scale, down_module in self.downs.items():
out_dict["prediction_" + str(scale).replace("-", ".")] = down_module(x)
return out_dict
def detach_kp(kp):
return {key: value.detach() for key, value in kp.items()}
class GeneratorFullModel(torch.nn.Module):
"""
Merge all generator related updates into single model for better multi-gpu usage
"""
def __init__(
self,
kp_extractor,
bg_predictor,
dense_motion_network,
inpainting_network,
train_params,
*kwargs,
):
super(GeneratorFullModel, self).__init__()
self.kp_extractor = kp_extractor
self.inpainting_network = inpainting_network
self.dense_motion_network = dense_motion_network
self.bg_predictor = None
if bg_predictor:
self.bg_predictor = bg_predictor
self.bg_start = train_params["bg_start"]
self.train_params = train_params
self.scales = train_params["scales"]
self.pyramid = ImagePyramide(self.scales, inpainting_network.num_channels)
if torch.cuda.is_available():
self.pyramid = self.pyramid.cuda()
self.loss_weights = train_params["loss_weights"]
self.dropout_epoch = train_params["dropout_epoch"]
self.dropout_maxp = train_params["dropout_maxp"]
self.dropout_inc_epoch = train_params["dropout_inc_epoch"]
self.dropout_startp = train_params["dropout_startp"]
if sum(self.loss_weights["perceptual"]) != 0:
self.vgg = Vgg19()
if torch.cuda.is_available():
self.vgg = self.vgg.cuda()
def forward(self, x, epoch):
kp_source = self.kp_extractor(x["source"])
kp_driving = self.kp_extractor(x["driving"])
bg_param = None
if self.bg_predictor:
if epoch >= self.bg_start:
bg_param = self.bg_predictor(x["source"], x["driving"])
if epoch >= self.dropout_epoch:
dropout_flag = False
dropout_p = 0
else:
# dropout_p will linearly increase from dropout_startp to dropout_maxp
dropout_flag = True
dropout_p = min(
epoch / self.dropout_inc_epoch * self.dropout_maxp
+ self.dropout_startp,
self.dropout_maxp,
)
dense_motion = self.dense_motion_network(
source_image=x["source"],
kp_driving=kp_driving,
kp_source=kp_source,
bg_param=bg_param,
dropout_flag=dropout_flag,
dropout_p=dropout_p,
)
generated = self.inpainting_network(x["source"], dense_motion)
generated.update({"kp_source": kp_source, "kp_driving": kp_driving})
loss_values = {}
pyramide_real = self.pyramid(x["driving"])
pyramide_generated = self.pyramid(generated["prediction"])
# reconstruction loss
if sum(self.loss_weights["perceptual"]) != 0:
value_total = 0
for scale in self.scales:
x_vgg = self.vgg(pyramide_generated["prediction_" + str(scale)])
y_vgg = self.vgg(pyramide_real["prediction_" + str(scale)])
for i, weight in enumerate(self.loss_weights["perceptual"]):
value = torch.abs(x_vgg[i] - y_vgg[i].detach()).mean()
value_total += self.loss_weights["perceptual"][i] * value
loss_values["perceptual"] = value_total
# equivariance loss
if self.loss_weights["equivariance_value"] != 0:
transform_random = TPS(
mode="random",
bs=x["driving"].shape[0],
**self.train_params["transform_params"],
)
transform_grid = transform_random.transform_frame(x["driving"])
transformed_frame = F.grid_sample(
x["driving"],
transform_grid,
padding_mode="reflection",
align_corners=True,
)
transformed_kp = self.kp_extractor(transformed_frame)
generated["transformed_frame"] = transformed_frame
generated["transformed_kp"] = transformed_kp
warped = transform_random.warp_coordinates(transformed_kp["fg_kp"])
kp_d = kp_driving["fg_kp"]
value = torch.abs(kp_d - warped).mean()
loss_values["equivariance_value"] = (
self.loss_weights["equivariance_value"] * value
)
# warp loss
if self.loss_weights["warp_loss"] != 0:
occlusion_map = generated["occlusion_map"]
encode_map = self.inpainting_network.get_encode(x["driving"], occlusion_map)
decode_map = generated["warped_encoder_maps"]
value = 0
for i in range(len(encode_map)):
value += torch.abs(encode_map[i] - decode_map[-i - 1]).mean()
loss_values["warp_loss"] = self.loss_weights["warp_loss"] * value
# bg loss
if (
self.bg_predictor
and epoch >= self.bg_start
and self.loss_weights["bg"] != 0
):
bg_param_reverse = self.bg_predictor(x["driving"], x["source"])
value = torch.matmul(bg_param, bg_param_reverse)
eye = torch.eye(3).view(1, 1, 3, 3).type(value.type())
value = torch.abs(eye - value).mean()
loss_values["bg"] = self.loss_weights["bg"] * value
return loss_values, generated