mirror of
https://github.com/ostris/ai-toolkit.git
synced 2026-05-01 03:31:35 +00:00
Work on vae trainer
This commit is contained in:
229
jobs/process/models/critic.py
Normal file
229
jobs/process/models/critic.py
Normal file
@@ -0,0 +1,229 @@
|
||||
import glob
|
||||
import os
|
||||
from typing import TYPE_CHECKING, Union
|
||||
|
||||
import numpy as np
|
||||
import torch
|
||||
import torch.nn as nn
|
||||
from safetensors.torch import load_file, save_file
|
||||
|
||||
from toolkit.losses import get_gradient_penalty
|
||||
from toolkit.metadata import get_meta_for_safetensors
|
||||
from toolkit.optimizer import get_optimizer
|
||||
from toolkit.train_tools import get_torch_dtype
|
||||
|
||||
|
||||
class MeanReduce(nn.Module):
|
||||
def __init__(self):
|
||||
super().__init__()
|
||||
|
||||
def forward(self, inputs):
|
||||
# global mean over spatial dims (keeps channel/batch)
|
||||
return torch.mean(inputs, dim=(2, 3), keepdim=True)
|
||||
|
||||
|
||||
class SelfAttention2d(nn.Module):
|
||||
"""
|
||||
Lightweight self-attention layer (SAGAN-style) that keeps spatial
|
||||
resolution unchanged. Adds minimal params / compute but improves
|
||||
long-range modelling – helpful for variable-sized inputs.
|
||||
"""
|
||||
def __init__(self, in_channels: int):
|
||||
super().__init__()
|
||||
self.query = nn.Conv1d(in_channels, in_channels // 8, 1)
|
||||
self.key = nn.Conv1d(in_channels, in_channels // 8, 1)
|
||||
self.value = nn.Conv1d(in_channels, in_channels, 1)
|
||||
self.gamma = nn.Parameter(torch.zeros(1))
|
||||
|
||||
def forward(self, x):
|
||||
B, C, H, W = x.shape
|
||||
flat = x.view(B, C, H * W) # (B,C,N)
|
||||
q = self.query(flat).permute(0, 2, 1) # (B,N,C//8)
|
||||
k = self.key(flat) # (B,C//8,N)
|
||||
attn = torch.bmm(q, k) # (B,N,N)
|
||||
attn = attn.softmax(dim=-1) # softmax along last dim
|
||||
v = self.value(flat) # (B,C,N)
|
||||
out = torch.bmm(v, attn.permute(0, 2, 1)) # (B,C,N)
|
||||
out = out.view(B, C, H, W) # restore spatial dims
|
||||
return self.gamma * out + x # residual
|
||||
|
||||
|
||||
class CriticModel(nn.Module):
|
||||
def __init__(self, base_channels: int = 64):
|
||||
super().__init__()
|
||||
|
||||
def sn_conv(in_c, out_c, k, s, p):
|
||||
return nn.utils.spectral_norm(
|
||||
nn.Conv2d(in_c, out_c, kernel_size=k, stride=s, padding=p)
|
||||
)
|
||||
|
||||
layers = [
|
||||
# initial down-sample
|
||||
sn_conv(3, base_channels, 3, 2, 1),
|
||||
nn.LeakyReLU(0.2, inplace=True),
|
||||
]
|
||||
|
||||
in_c = base_channels
|
||||
# progressive downsamples ×3 (64→128→256→512)
|
||||
for _ in range(3):
|
||||
out_c = min(in_c * 2, 1024)
|
||||
layers += [
|
||||
sn_conv(in_c, out_c, 3, 2, 1),
|
||||
nn.LeakyReLU(0.2, inplace=True),
|
||||
]
|
||||
# single attention block after reaching 256 channels
|
||||
if out_c == 256:
|
||||
layers += [SelfAttention2d(out_c)]
|
||||
in_c = out_c
|
||||
|
||||
# extra depth (keeps spatial size)
|
||||
layers += [
|
||||
sn_conv(in_c, 1024, 3, 1, 1),
|
||||
nn.LeakyReLU(0.2, inplace=True),
|
||||
|
||||
# final 1-channel prediction map
|
||||
sn_conv(1024, 1, 3, 1, 1),
|
||||
MeanReduce(), # → (B,1,1,1)
|
||||
nn.Flatten(), # → (B,1)
|
||||
]
|
||||
|
||||
self.main = nn.Sequential(*layers)
|
||||
|
||||
def forward(self, inputs):
|
||||
# force full-precision inside AMP ctx for stability
|
||||
with torch.cuda.amp.autocast(False):
|
||||
return self.main(inputs.float())
|
||||
|
||||
|
||||
if TYPE_CHECKING:
|
||||
from jobs.process.TrainVAEProcess import TrainVAEProcess
|
||||
from jobs.process.TrainESRGANProcess import TrainESRGANProcess
|
||||
|
||||
|
||||
class Critic:
|
||||
process: Union['TrainVAEProcess', 'TrainESRGANProcess']
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
learning_rate=1e-5,
|
||||
device='cpu',
|
||||
optimizer='adam',
|
||||
num_critic_per_gen=1,
|
||||
dtype='float32',
|
||||
lambda_gp=10,
|
||||
start_step=0,
|
||||
warmup_steps=1000,
|
||||
process=None,
|
||||
optimizer_params=None,
|
||||
):
|
||||
self.learning_rate = learning_rate
|
||||
self.device = device
|
||||
self.optimizer_type = optimizer
|
||||
self.num_critic_per_gen = num_critic_per_gen
|
||||
self.dtype = dtype
|
||||
self.torch_dtype = get_torch_dtype(self.dtype)
|
||||
self.process = process
|
||||
self.model = None
|
||||
self.optimizer = None
|
||||
self.scheduler = None
|
||||
self.warmup_steps = warmup_steps
|
||||
self.start_step = start_step
|
||||
self.lambda_gp = lambda_gp
|
||||
|
||||
if optimizer_params is None:
|
||||
optimizer_params = {}
|
||||
self.optimizer_params = optimizer_params
|
||||
self.print = self.process.print
|
||||
print(f" Critic config: {self.__dict__}")
|
||||
|
||||
def setup(self):
|
||||
self.model = CriticModel().to(self.device)
|
||||
self.load_weights()
|
||||
self.model.train()
|
||||
self.model.requires_grad_(True)
|
||||
params = self.model.parameters()
|
||||
self.optimizer = get_optimizer(
|
||||
params,
|
||||
self.optimizer_type,
|
||||
self.learning_rate,
|
||||
optimizer_params=self.optimizer_params,
|
||||
)
|
||||
self.scheduler = torch.optim.lr_scheduler.ConstantLR(
|
||||
self.optimizer,
|
||||
total_iters=self.process.max_steps * self.num_critic_per_gen,
|
||||
factor=1,
|
||||
verbose=False,
|
||||
)
|
||||
|
||||
def load_weights(self):
|
||||
path_to_load = None
|
||||
self.print(f"Critic: Looking for latest checkpoint in {self.process.save_root}")
|
||||
files = glob.glob(os.path.join(self.process.save_root, f"CRITIC_{self.process.job.name}*.safetensors"))
|
||||
if files:
|
||||
latest_file = max(files, key=os.path.getmtime)
|
||||
print(f" - Latest checkpoint is: {latest_file}")
|
||||
path_to_load = latest_file
|
||||
else:
|
||||
self.print(" - No checkpoint found, starting from scratch")
|
||||
if path_to_load:
|
||||
self.model.load_state_dict(load_file(path_to_load))
|
||||
|
||||
def save(self, step=None):
|
||||
self.process.update_training_metadata()
|
||||
save_meta = get_meta_for_safetensors(self.process.meta, self.process.job.name)
|
||||
step_num = f"_{str(step).zfill(9)}" if step is not None else ''
|
||||
save_path = os.path.join(
|
||||
self.process.save_root, f"CRITIC_{self.process.job.name}{step_num}.safetensors"
|
||||
)
|
||||
save_file(self.model.state_dict(), save_path, save_meta)
|
||||
self.print(f"Saved critic to {save_path}")
|
||||
|
||||
def get_critic_loss(self, vgg_output):
|
||||
# (caller still passes combined [pred|target] images)
|
||||
if self.start_step > self.process.step_num:
|
||||
return torch.tensor(0.0, dtype=self.torch_dtype, device=self.device)
|
||||
|
||||
warmup_scaler = 1.0
|
||||
if self.process.step_num < self.start_step + self.warmup_steps:
|
||||
warmup_scaler = (self.process.step_num - self.start_step) / self.warmup_steps
|
||||
|
||||
self.model.eval()
|
||||
self.model.requires_grad_(False)
|
||||
|
||||
vgg_pred, _ = torch.chunk(vgg_output.float(), 2, dim=0)
|
||||
stacked_output = self.model(vgg_pred)
|
||||
return (-torch.mean(stacked_output)) * warmup_scaler
|
||||
|
||||
def step(self, vgg_output):
|
||||
self.model.train()
|
||||
self.model.requires_grad_(True)
|
||||
self.optimizer.zero_grad()
|
||||
|
||||
critic_losses = []
|
||||
inputs = vgg_output.detach().to(self.device, dtype=torch.float32)
|
||||
|
||||
vgg_pred, vgg_target = torch.chunk(inputs, 2, dim=0)
|
||||
stacked_output = self.model(inputs).float()
|
||||
out_pred, out_target = torch.chunk(stacked_output, 2, dim=0)
|
||||
|
||||
# hinge loss + gradient penalty
|
||||
loss_real = torch.relu(1.0 - out_target).mean()
|
||||
loss_fake = torch.relu(1.0 + out_pred).mean()
|
||||
gradient_penalty = get_gradient_penalty(self.model, vgg_target, vgg_pred, self.device)
|
||||
critic_loss = loss_real + loss_fake + self.lambda_gp * gradient_penalty
|
||||
|
||||
critic_loss.backward()
|
||||
torch.nn.utils.clip_grad_norm_(self.model.parameters(), 1.0)
|
||||
self.optimizer.step()
|
||||
self.scheduler.step()
|
||||
critic_losses.append(critic_loss.item())
|
||||
|
||||
return float(np.mean(critic_losses))
|
||||
|
||||
def get_lr(self):
|
||||
if self.optimizer_type.startswith('dadaptation'):
|
||||
return (
|
||||
self.optimizer.param_groups[0]["d"]
|
||||
* self.optimizer.param_groups[0]["lr"]
|
||||
)
|
||||
return self.optimizer.param_groups[0]["lr"]
|
||||
@@ -33,11 +33,20 @@ class Vgg19Critic(nn.Module):
|
||||
super(Vgg19Critic, self).__init__()
|
||||
self.main = nn.Sequential(
|
||||
# input (bs, 512, 32, 32)
|
||||
nn.Conv2d(512, 1024, kernel_size=3, stride=2, padding=1),
|
||||
# nn.Conv2d(512, 1024, kernel_size=3, stride=2, padding=1),
|
||||
nn.utils.spectral_norm( # SN keeps D’s scale in check
|
||||
nn.Conv2d(512, 1024, kernel_size=3, stride=2, padding=1)
|
||||
),
|
||||
nn.LeakyReLU(0.2), # (bs, 512, 16, 16)
|
||||
nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1),
|
||||
# nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1),
|
||||
nn.utils.spectral_norm(
|
||||
nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1)
|
||||
),
|
||||
nn.LeakyReLU(0.2), # (bs, 512, 8, 8)
|
||||
nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1),
|
||||
# nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1),
|
||||
nn.utils.spectral_norm(
|
||||
nn.Conv2d(1024, 1024, kernel_size=3, stride=2, padding=1)
|
||||
),
|
||||
# (bs, 1, 4, 4)
|
||||
MeanReduce(), # (bs, 1, 1, 1)
|
||||
nn.Flatten(), # (bs, 1)
|
||||
@@ -47,7 +56,9 @@ class Vgg19Critic(nn.Module):
|
||||
)
|
||||
|
||||
def forward(self, inputs):
|
||||
return self.main(inputs)
|
||||
# return self.main(inputs)
|
||||
with torch.cuda.amp.autocast(False):
|
||||
return self.main(inputs.float())
|
||||
|
||||
|
||||
if TYPE_CHECKING:
|
||||
@@ -92,7 +103,7 @@ class Critic:
|
||||
print(f" Critic config: {self.__dict__}")
|
||||
|
||||
def setup(self):
|
||||
self.model = Vgg19Critic().to(self.device, dtype=self.torch_dtype)
|
||||
self.model = Vgg19Critic().to(self.device)
|
||||
self.load_weights()
|
||||
self.model.train()
|
||||
self.model.requires_grad_(True)
|
||||
@@ -142,7 +153,8 @@ class Critic:
|
||||
# set model to not train for generator loss
|
||||
self.model.eval()
|
||||
self.model.requires_grad_(False)
|
||||
vgg_pred, vgg_target = torch.chunk(vgg_output, 2, dim=0)
|
||||
# vgg_pred, vgg_target = torch.chunk(vgg_output, 2, dim=0)
|
||||
vgg_pred, vgg_target = torch.chunk(vgg_output.float(), 2, dim=0)
|
||||
|
||||
# run model
|
||||
stacked_output = self.model(vgg_pred)
|
||||
@@ -157,20 +169,34 @@ class Critic:
|
||||
self.optimizer.zero_grad()
|
||||
|
||||
critic_losses = []
|
||||
inputs = vgg_output.detach()
|
||||
inputs = inputs.to(self.device, dtype=self.torch_dtype)
|
||||
# inputs = vgg_output.detach()
|
||||
# inputs = inputs.to(self.device, dtype=self.torch_dtype)
|
||||
inputs = vgg_output.detach().to(self.device, dtype=torch.float32)
|
||||
self.optimizer.zero_grad()
|
||||
|
||||
vgg_pred, vgg_target = torch.chunk(inputs, 2, dim=0)
|
||||
|
||||
# stacked_output = self.model(inputs).float()
|
||||
# out_pred, out_target = torch.chunk(stacked_output, 2, dim=0)
|
||||
|
||||
# # Compute gradient penalty
|
||||
# gradient_penalty = get_gradient_penalty(self.model, vgg_target, vgg_pred, self.device)
|
||||
|
||||
# # Compute WGAN-GP critic loss
|
||||
# critic_loss = -(torch.mean(out_target) - torch.mean(out_pred)) + self.lambda_gp * gradient_penalty
|
||||
|
||||
stacked_output = self.model(inputs).float()
|
||||
out_pred, out_target = torch.chunk(stacked_output, 2, dim=0)
|
||||
|
||||
# Compute gradient penalty
|
||||
# ── hinge loss ──
|
||||
loss_real = torch.relu(1.0 - out_target).mean()
|
||||
loss_fake = torch.relu(1.0 + out_pred).mean()
|
||||
|
||||
# gradient penalty (unchanged helper)
|
||||
gradient_penalty = get_gradient_penalty(self.model, vgg_target, vgg_pred, self.device)
|
||||
|
||||
# Compute WGAN-GP critic loss
|
||||
critic_loss = -(torch.mean(out_target) - torch.mean(out_pred)) + self.lambda_gp * gradient_penalty
|
||||
critic_loss = loss_real + loss_fake + self.lambda_gp * gradient_penalty
|
||||
|
||||
critic_loss.backward()
|
||||
torch.nn.utils.clip_grad_norm_(self.model.parameters(), 1.0)
|
||||
self.optimizer.step()
|
||||
|
||||
Reference in New Issue
Block a user