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7 Commits
Author SHA1 Message Date
Phil Wang d4420248f1 tqdm auto instead 2022-06-29 19:48:49 -07:00
Phil Wang a536e5bee9 reorganize elucidating code 2022-06-29 08:49:38 -07:00
Phil Wang 1b85379d3a add clamping option to elucidated diffusion 2022-06-29 08:32:10 -07:00
Phil Wang 8859864f63 patch 2022-06-29 07:55:11 -07:00
Phil Wang 32657f035f Merge pull request #52 from AryaAftab/patch-1
Solve issue #26
2022-06-29 07:54:48 -07:00
Arya Aftab d97bc0278c Solve issue #26 2022-06-29 11:42:54 +04:30
Phil Wang 8408775cfc fix bug in elucidating sampling 2022-06-28 17:52:02 -07:00
3 changed files with 34 additions and 31 deletions
@@ -15,10 +15,10 @@ from torch.optim import Adam
from torchvision import transforms, utils
from PIL import Image
from tqdm import tqdm
from einops import rearrange, reduce
from einops.layers.torch import Rearrange
from tqdm.auto import tqdm
from ema_pytorch import EMA
# helpers functions
@@ -96,13 +96,30 @@ class ElucidatedDiffusion(nn.Module):
def c_noise(self, sigma):
return log(sigma) * 0.25
# noise distribution
# preconditioned network output
# equation (7) in the paper
def noise_distribution(self, batch_size):
return (self.P_mean + self.P_std * torch.randn((batch_size,), device = self.device)).exp()
def preconditioned_network_forward(self, noised_images, sigma, clamp = False):
batch, device = noised_images.shape[0], noised_images.device
def loss_weight(self, sigma):
return (sigma ** 2 + self.sigma_data ** 2) * (sigma * self.sigma_data) ** -2
if isinstance(sigma, float):
sigma = torch.full((batch,), sigma, device = device)
padded_sigma = rearrange(sigma, 'b -> b 1 1 1')
net_out = self.net(
self.c_in(padded_sigma) * noised_images,
self.c_noise(sigma)
)
out = self.c_skip(padded_sigma) * noised_images + self.c_out(padded_sigma) * net_out
if clamp:
out = out.clamp(-1., 1.)
return out
# sampling
# sample schedule
# equation (5) in the paper
@@ -119,28 +136,8 @@ class ElucidatedDiffusion(nn.Module):
sigmas = F.pad(sigmas, (0, 1), value = 0.) # last step is sigma value of 0.
return sigmas
# preconditioned network output
# equation (7) in the paper
def preconditioned_network_forward(self, noised_images, sigma):
batch, device = noised_images.shape[0], noised_images.device
if isinstance(sigma, float):
sigma = torch.full((batch,), sigma, device = device)
padded_sigma = rearrange(sigma, 'b -> b 1 1 1')
net_out = self.net(
self.c_in(padded_sigma) * noised_images,
self.c_noise(sigma)
)
return self.c_skip(padded_sigma) * noised_images + self.c_out(padded_sigma) * net_out
# sampling
@torch.no_grad()
def sample(self, batch_size = 16, num_sample_steps = None):
def sample(self, batch_size = 16, num_sample_steps = None, clamp = True):
num_sample_steps = default(num_sample_steps, self.num_sample_steps)
shape = (batch_size, self.channels, self.image_size, self.image_size)
@@ -168,12 +165,12 @@ class ElucidatedDiffusion(nn.Module):
for sigma, sigma_next, gamma in tqdm(sigmas_and_gammas, desc = 'sampling time step'):
sigma, sigma_next, gamma = map(lambda t: t.item(), (sigma, sigma_next, gamma))
eps = gamma * torch.randn(shape, device = self.device)
eps = self.S_noise * torch.randn(shape, device = self.device) # stochastic sampling
sigma_hat = sigma + gamma * sigma
images_hat = images + sqrt(sigma_hat ** 2 - sigma ** 2) * eps
model_output = self.preconditioned_network_forward(images_hat, sigma_hat)
model_output = self.preconditioned_network_forward(images_hat, sigma_hat, clamp = clamp)
denoised_over_sigma = (images_hat - model_output) / sigma_hat
images_next = images_hat + (sigma_next - sigma_hat) * denoised_over_sigma
@@ -181,7 +178,7 @@ class ElucidatedDiffusion(nn.Module):
# second order correction, if not the last timestep
if sigma_next != 0:
model_output_next = self.preconditioned_network_forward(images_next, sigma_next)
model_output_next = self.preconditioned_network_forward(images_next, sigma_next, clamp = clamp)
denoised_prime_over_sigma = (images_next - model_output_next) / sigma_next
images_next = images_hat + 0.5 * (sigma_next - sigma_hat) * (denoised_over_sigma + denoised_prime_over_sigma)
@@ -192,6 +189,12 @@ class ElucidatedDiffusion(nn.Module):
# training
def loss_weight(self, sigma):
return (sigma ** 2 + self.sigma_data ** 2) * (sigma * self.sigma_data) ** -2
def noise_distribution(self, batch_size):
return (self.P_mean + self.P_std * torch.randn((batch_size,), device = self.device)).exp()
def forward(self, images):
batch_size, c, h, w, device, image_size, channels = *images.shape, images.device, self.image_size, self.channels
+1 -1
View File
@@ -3,7 +3,7 @@ from setuptools import setup, find_packages
setup(
name = 'denoising-diffusion-pytorch',
packages = find_packages(),
version = '0.23.0',
version = '0.23.4',
license='MIT',
description = 'Denoising Diffusion Probabilistic Models - Pytorch',
author = 'Phil Wang',