aboutsummaryrefslogtreecommitdiffstats
path: root/ldm/models/diffusion/ddpm.py
diff options
context:
space:
mode:
Diffstat (limited to 'ldm/models/diffusion/ddpm.py')
-rw-r--r--ldm/models/diffusion/ddpm.py1445
1 files changed, 0 insertions, 1445 deletions
diff --git a/ldm/models/diffusion/ddpm.py b/ldm/models/diffusion/ddpm.py
deleted file mode 100644
index bbedd04c..00000000
--- a/ldm/models/diffusion/ddpm.py
+++ /dev/null
@@ -1,1445 +0,0 @@
-"""
-wild mixture of
-https://github.com/lucidrains/denoising-diffusion-pytorch/blob/7706bdfc6f527f58d33f84b7b522e61e6e3164b3/denoising_diffusion_pytorch/denoising_diffusion_pytorch.py
-https://github.com/openai/improved-diffusion/blob/e94489283bb876ac1477d5dd7709bbbd2d9902ce/improved_diffusion/gaussian_diffusion.py
-https://github.com/CompVis/taming-transformers
--- merci
-"""
-
-import torch
-import torch.nn as nn
-import numpy as np
-import pytorch_lightning as pl
-from torch.optim.lr_scheduler import LambdaLR
-from einops import rearrange, repeat
-from contextlib import contextmanager
-from functools import partial
-from tqdm import tqdm
-from torchvision.utils import make_grid
-from pytorch_lightning.utilities.distributed import rank_zero_only
-
-from ldm.util import log_txt_as_img, exists, default, ismap, isimage, mean_flat, count_params, instantiate_from_config
-from ldm.modules.ema import LitEma
-from ldm.modules.distributions.distributions import normal_kl, DiagonalGaussianDistribution
-from ldm.models.autoencoder import VQModelInterface, IdentityFirstStage, AutoencoderKL
-from ldm.modules.diffusionmodules.util import make_beta_schedule, extract_into_tensor, noise_like
-from ldm.models.diffusion.ddim import DDIMSampler
-
-
-__conditioning_keys__ = {'concat': 'c_concat',
- 'crossattn': 'c_crossattn',
- 'adm': 'y'}
-
-
-def disabled_train(self, mode=True):
- """Overwrite model.train with this function to make sure train/eval mode
- does not change anymore."""
- return self
-
-
-def uniform_on_device(r1, r2, shape, device):
- return (r1 - r2) * torch.rand(*shape, device=device) + r2
-
-
-class DDPM(pl.LightningModule):
- # classic DDPM with Gaussian diffusion, in image space
- def __init__(self,
- unet_config,
- timesteps=1000,
- beta_schedule="linear",
- loss_type="l2",
- ckpt_path=None,
- ignore_keys=[],
- load_only_unet=False,
- monitor="val/loss",
- use_ema=True,
- first_stage_key="image",
- image_size=256,
- channels=3,
- log_every_t=100,
- clip_denoised=True,
- linear_start=1e-4,
- linear_end=2e-2,
- cosine_s=8e-3,
- given_betas=None,
- original_elbo_weight=0.,
- v_posterior=0., # weight for choosing posterior variance as sigma = (1-v) * beta_tilde + v * beta
- l_simple_weight=1.,
- conditioning_key=None,
- parameterization="eps", # all assuming fixed variance schedules
- scheduler_config=None,
- use_positional_encodings=False,
- learn_logvar=False,
- logvar_init=0.,
- ):
- super().__init__()
- assert parameterization in ["eps", "x0"], 'currently only supporting "eps" and "x0"'
- self.parameterization = parameterization
- print(f"{self.__class__.__name__}: Running in {self.parameterization}-prediction mode")
- self.cond_stage_model = None
- self.clip_denoised = clip_denoised
- self.log_every_t = log_every_t
- self.first_stage_key = first_stage_key
- self.image_size = image_size # try conv?
- self.channels = channels
- self.use_positional_encodings = use_positional_encodings
- self.model = DiffusionWrapper(unet_config, conditioning_key)
- count_params(self.model, verbose=True)
- self.use_ema = use_ema
- if self.use_ema:
- self.model_ema = LitEma(self.model)
- print(f"Keeping EMAs of {len(list(self.model_ema.buffers()))}.")
-
- self.use_scheduler = scheduler_config is not None
- if self.use_scheduler:
- self.scheduler_config = scheduler_config
-
- self.v_posterior = v_posterior
- self.original_elbo_weight = original_elbo_weight
- self.l_simple_weight = l_simple_weight
-
- if monitor is not None:
- self.monitor = monitor
- if ckpt_path is not None:
- self.init_from_ckpt(ckpt_path, ignore_keys=ignore_keys, only_model=load_only_unet)
-
- self.register_schedule(given_betas=given_betas, beta_schedule=beta_schedule, timesteps=timesteps,
- linear_start=linear_start, linear_end=linear_end, cosine_s=cosine_s)
-
- self.loss_type = loss_type
-
- self.learn_logvar = learn_logvar
- self.logvar = torch.full(fill_value=logvar_init, size=(self.num_timesteps,))
- if self.learn_logvar:
- self.logvar = nn.Parameter(self.logvar, requires_grad=True)
-
-
- def register_schedule(self, given_betas=None, beta_schedule="linear", timesteps=1000,
- linear_start=1e-4, linear_end=2e-2, cosine_s=8e-3):
- if exists(given_betas):
- betas = given_betas
- else:
- betas = make_beta_schedule(beta_schedule, timesteps, linear_start=linear_start, linear_end=linear_end,
- cosine_s=cosine_s)
- alphas = 1. - betas
- alphas_cumprod = np.cumprod(alphas, axis=0)
- alphas_cumprod_prev = np.append(1., alphas_cumprod[:-1])
-
- timesteps, = betas.shape
- self.num_timesteps = int(timesteps)
- self.linear_start = linear_start
- self.linear_end = linear_end
- assert alphas_cumprod.shape[0] == self.num_timesteps, 'alphas have to be defined for each timestep'
-
- to_torch = partial(torch.tensor, dtype=torch.float32)
-
- self.register_buffer('betas', to_torch(betas))
- self.register_buffer('alphas_cumprod', to_torch(alphas_cumprod))
- self.register_buffer('alphas_cumprod_prev', to_torch(alphas_cumprod_prev))
-
- # calculations for diffusion q(x_t | x_{t-1}) and others
- self.register_buffer('sqrt_alphas_cumprod', to_torch(np.sqrt(alphas_cumprod)))
- self.register_buffer('sqrt_one_minus_alphas_cumprod', to_torch(np.sqrt(1. - alphas_cumprod)))
- self.register_buffer('log_one_minus_alphas_cumprod', to_torch(np.log(1. - alphas_cumprod)))
- self.register_buffer('sqrt_recip_alphas_cumprod', to_torch(np.sqrt(1. / alphas_cumprod)))
- self.register_buffer('sqrt_recipm1_alphas_cumprod', to_torch(np.sqrt(1. / alphas_cumprod - 1)))
-
- # calculations for posterior q(x_{t-1} | x_t, x_0)
- posterior_variance = (1 - self.v_posterior) * betas * (1. - alphas_cumprod_prev) / (
- 1. - alphas_cumprod) + self.v_posterior * betas
- # above: equal to 1. / (1. / (1. - alpha_cumprod_tm1) + alpha_t / beta_t)
- self.register_buffer('posterior_variance', to_torch(posterior_variance))
- # below: log calculation clipped because the posterior variance is 0 at the beginning of the diffusion chain
- self.register_buffer('posterior_log_variance_clipped', to_torch(np.log(np.maximum(posterior_variance, 1e-20))))
- self.register_buffer('posterior_mean_coef1', to_torch(
- betas * np.sqrt(alphas_cumprod_prev) / (1. - alphas_cumprod)))
- self.register_buffer('posterior_mean_coef2', to_torch(
- (1. - alphas_cumprod_prev) * np.sqrt(alphas) / (1. - alphas_cumprod)))
-
- if self.parameterization == "eps":
- lvlb_weights = self.betas ** 2 / (
- 2 * self.posterior_variance * to_torch(alphas) * (1 - self.alphas_cumprod))
- elif self.parameterization == "x0":
- lvlb_weights = 0.5 * np.sqrt(torch.Tensor(alphas_cumprod)) / (2. * 1 - torch.Tensor(alphas_cumprod))
- else:
- raise NotImplementedError("mu not supported")
- # TODO how to choose this term
- lvlb_weights[0] = lvlb_weights[1]
- self.register_buffer('lvlb_weights', lvlb_weights, persistent=False)
- assert not torch.isnan(self.lvlb_weights).all()
-
- @contextmanager
- def ema_scope(self, context=None):
- if self.use_ema:
- self.model_ema.store(self.model.parameters())
- self.model_ema.copy_to(self.model)
- if context is not None:
- print(f"{context}: Switched to EMA weights")
- try:
- yield None
- finally:
- if self.use_ema:
- self.model_ema.restore(self.model.parameters())
- if context is not None:
- print(f"{context}: Restored training weights")
-
- def init_from_ckpt(self, path, ignore_keys=list(), only_model=False):
- sd = torch.load(path, map_location="cpu")
- if "state_dict" in list(sd.keys()):
- sd = sd["state_dict"]
- keys = list(sd.keys())
- for k in keys:
- for ik in ignore_keys:
- if k.startswith(ik):
- print("Deleting key {} from state_dict.".format(k))
- del sd[k]
- missing, unexpected = self.load_state_dict(sd, strict=False) if not only_model else self.model.load_state_dict(
- sd, strict=False)
- print(f"Restored from {path} with {len(missing)} missing and {len(unexpected)} unexpected keys")
- if len(missing) > 0:
- print(f"Missing Keys: {missing}")
- if len(unexpected) > 0:
- print(f"Unexpected Keys: {unexpected}")
-
- def q_mean_variance(self, x_start, t):
- """
- Get the distribution q(x_t | x_0).
- :param x_start: the [N x C x ...] tensor of noiseless inputs.
- :param t: the number of diffusion steps (minus 1). Here, 0 means one step.
- :return: A tuple (mean, variance, log_variance), all of x_start's shape.
- """
- mean = (extract_into_tensor(self.sqrt_alphas_cumprod, t, x_start.shape) * x_start)
- variance = extract_into_tensor(1.0 - self.alphas_cumprod, t, x_start.shape)
- log_variance = extract_into_tensor(self.log_one_minus_alphas_cumprod, t, x_start.shape)
- return mean, variance, log_variance
-
- def predict_start_from_noise(self, x_t, t, noise):
- return (
- extract_into_tensor(self.sqrt_recip_alphas_cumprod, t, x_t.shape) * x_t -
- extract_into_tensor(self.sqrt_recipm1_alphas_cumprod, t, x_t.shape) * noise
- )
-
- def q_posterior(self, x_start, x_t, t):
- posterior_mean = (
- extract_into_tensor(self.posterior_mean_coef1, t, x_t.shape) * x_start +
- extract_into_tensor(self.posterior_mean_coef2, t, x_t.shape) * x_t
- )
- posterior_variance = extract_into_tensor(self.posterior_variance, t, x_t.shape)
- posterior_log_variance_clipped = extract_into_tensor(self.posterior_log_variance_clipped, t, x_t.shape)
- return posterior_mean, posterior_variance, posterior_log_variance_clipped
-
- def p_mean_variance(self, x, t, clip_denoised: bool):
- model_out = self.model(x, t)
- if self.parameterization == "eps":
- x_recon = self.predict_start_from_noise(x, t=t, noise=model_out)
- elif self.parameterization == "x0":
- x_recon = model_out
- if clip_denoised:
- x_recon.clamp_(-1., 1.)
-
- model_mean, posterior_variance, posterior_log_variance = self.q_posterior(x_start=x_recon, x_t=x, t=t)
- return model_mean, posterior_variance, posterior_log_variance
-
- @torch.no_grad()
- def p_sample(self, x, t, clip_denoised=True, repeat_noise=False):
- b, *_, device = *x.shape, x.device
- model_mean, _, model_log_variance = self.p_mean_variance(x=x, t=t, clip_denoised=clip_denoised)
- noise = noise_like(x.shape, device, repeat_noise)
- # no noise when t == 0
- nonzero_mask = (1 - (t == 0).float()).reshape(b, *((1,) * (len(x.shape) - 1)))
- return model_mean + nonzero_mask * (0.5 * model_log_variance).exp() * noise
-
- @torch.no_grad()
- def p_sample_loop(self, shape, return_intermediates=False):
- device = self.betas.device
- b = shape[0]
- img = torch.randn(shape, device=device)
- intermediates = [img]
- for i in tqdm(reversed(range(0, self.num_timesteps)), desc='Sampling t', total=self.num_timesteps):
- img = self.p_sample(img, torch.full((b,), i, device=device, dtype=torch.long),
- clip_denoised=self.clip_denoised)
- if i % self.log_every_t == 0 or i == self.num_timesteps - 1:
- intermediates.append(img)
- if return_intermediates:
- return img, intermediates
- return img
-
- @torch.no_grad()
- def sample(self, batch_size=16, return_intermediates=False):
- image_size = self.image_size
- channels = self.channels
- return self.p_sample_loop((batch_size, channels, image_size, image_size),
- return_intermediates=return_intermediates)
-
- def q_sample(self, x_start, t, noise=None):
- noise = default(noise, lambda: torch.randn_like(x_start))
- return (extract_into_tensor(self.sqrt_alphas_cumprod, t, x_start.shape) * x_start +
- extract_into_tensor(self.sqrt_one_minus_alphas_cumprod, t, x_start.shape) * noise)
-
- def get_loss(self, pred, target, mean=True):
- if self.loss_type == 'l1':
- loss = (target - pred).abs()
- if mean:
- loss = loss.mean()
- elif self.loss_type == 'l2':
- if mean:
- loss = torch.nn.functional.mse_loss(target, pred)
- else:
- loss = torch.nn.functional.mse_loss(target, pred, reduction='none')
- else:
- raise NotImplementedError("unknown loss type '{loss_type}'")
-
- return loss
-
- def p_losses(self, x_start, t, noise=None):
- noise = default(noise, lambda: torch.randn_like(x_start))
- x_noisy = self.q_sample(x_start=x_start, t=t, noise=noise)
- model_out = self.model(x_noisy, t)
-
- loss_dict = {}
- if self.parameterization == "eps":
- target = noise
- elif self.parameterization == "x0":
- target = x_start
- else:
- raise NotImplementedError(f"Paramterization {self.parameterization} not yet supported")
-
- loss = self.get_loss(model_out, target, mean=False).mean(dim=[1, 2, 3])
-
- log_prefix = 'train' if self.training else 'val'
-
- loss_dict.update({f'{log_prefix}/loss_simple': loss.mean()})
- loss_simple = loss.mean() * self.l_simple_weight
-
- loss_vlb = (self.lvlb_weights[t] * loss).mean()
- loss_dict.update({f'{log_prefix}/loss_vlb': loss_vlb})
-
- loss = loss_simple + self.original_elbo_weight * loss_vlb
-
- loss_dict.update({f'{log_prefix}/loss': loss})
-
- return loss, loss_dict
-
- def forward(self, x, *args, **kwargs):
- # b, c, h, w, device, img_size, = *x.shape, x.device, self.image_size
- # assert h == img_size and w == img_size, f'height and width of image must be {img_size}'
- t = torch.randint(0, self.num_timesteps, (x.shape[0],), device=self.device).long()
- return self.p_losses(x, t, *args, **kwargs)
-
- def get_input(self, batch, k):
- x = batch[k]
- if len(x.shape) == 3:
- x = x[..., None]
- x = rearrange(x, 'b h w c -> b c h w')
- x = x.to(memory_format=torch.contiguous_format).float()
- return x
-
- def shared_step(self, batch):
- x = self.get_input(batch, self.first_stage_key)
- loss, loss_dict = self(x)
- return loss, loss_dict
-
- def training_step(self, batch, batch_idx):
- loss, loss_dict = self.shared_step(batch)
-
- self.log_dict(loss_dict, prog_bar=True,
- logger=True, on_step=True, on_epoch=True)
-
- self.log("global_step", self.global_step,
- prog_bar=True, logger=True, on_step=True, on_epoch=False)
-
- if self.use_scheduler:
- lr = self.optimizers().param_groups[0]['lr']
- self.log('lr_abs', lr, prog_bar=True, logger=True, on_step=True, on_epoch=False)
-
- return loss
-
- @torch.no_grad()
- def validation_step(self, batch, batch_idx):
- _, loss_dict_no_ema = self.shared_step(batch)
- with self.ema_scope():
- _, loss_dict_ema = self.shared_step(batch)
- loss_dict_ema = {key + '_ema': loss_dict_ema[key] for key in loss_dict_ema}
- self.log_dict(loss_dict_no_ema, prog_bar=False, logger=True, on_step=False, on_epoch=True)
- self.log_dict(loss_dict_ema, prog_bar=False, logger=True, on_step=False, on_epoch=True)
-
- def on_train_batch_end(self, *args, **kwargs):
- if self.use_ema:
- self.model_ema(self.model)
-
- def _get_rows_from_list(self, samples):
- n_imgs_per_row = len(samples)
- denoise_grid = rearrange(samples, 'n b c h w -> b n c h w')
- denoise_grid = rearrange(denoise_grid, 'b n c h w -> (b n) c h w')
- denoise_grid = make_grid(denoise_grid, nrow=n_imgs_per_row)
- return denoise_grid
-
- @torch.no_grad()
- def log_images(self, batch, N=8, n_row=2, sample=True, return_keys=None, **kwargs):
- log = dict()
- x = self.get_input(batch, self.first_stage_key)
- N = min(x.shape[0], N)
- n_row = min(x.shape[0], n_row)
- x = x.to(self.device)[:N]
- log["inputs"] = x
-
- # get diffusion row
- diffusion_row = list()
- x_start = x[:n_row]
-
- for t in range(self.num_timesteps):
- if t % self.log_every_t == 0 or t == self.num_timesteps - 1:
- t = repeat(torch.tensor([t]), '1 -> b', b=n_row)
- t = t.to(self.device).long()
- noise = torch.randn_like(x_start)
- x_noisy = self.q_sample(x_start=x_start, t=t, noise=noise)
- diffusion_row.append(x_noisy)
-
- log["diffusion_row"] = self._get_rows_from_list(diffusion_row)
-
- if sample:
- # get denoise row
- with self.ema_scope("Plotting"):
- samples, denoise_row = self.sample(batch_size=N, return_intermediates=True)
-
- log["samples"] = samples
- log["denoise_row"] = self._get_rows_from_list(denoise_row)
-
- if return_keys:
- if np.intersect1d(list(log.keys()), return_keys).shape[0] == 0:
- return log
- else:
- return {key: log[key] for key in return_keys}
- return log
-
- def configure_optimizers(self):
- lr = self.learning_rate
- params = list(self.model.parameters())
- if self.learn_logvar:
- params = params + [self.logvar]
- opt = torch.optim.AdamW(params, lr=lr)
- return opt
-
-
-class LatentDiffusion(DDPM):
- """main class"""
- def __init__(self,
- first_stage_config,
- cond_stage_config,
- num_timesteps_cond=None,
- cond_stage_key="image",
- cond_stage_trainable=False,
- concat_mode=True,
- cond_stage_forward=None,
- conditioning_key=None,
- scale_factor=1.0,
- scale_by_std=False,
- *args, **kwargs):
- self.num_timesteps_cond = default(num_timesteps_cond, 1)
- self.scale_by_std = scale_by_std
- assert self.num_timesteps_cond <= kwargs['timesteps']
- # for backwards compatibility after implementation of DiffusionWrapper
- if conditioning_key is None:
- conditioning_key = 'concat' if concat_mode else 'crossattn'
- if cond_stage_config == '__is_unconditional__':
- conditioning_key = None
- ckpt_path = kwargs.pop("ckpt_path", None)
- ignore_keys = kwargs.pop("ignore_keys", [])
- super().__init__(conditioning_key=conditioning_key, *args, **kwargs)
- self.concat_mode = concat_mode
- self.cond_stage_trainable = cond_stage_trainable
- self.cond_stage_key = cond_stage_key
- try:
- self.num_downs = len(first_stage_config.params.ddconfig.ch_mult) - 1
- except:
- self.num_downs = 0
- if not scale_by_std:
- self.scale_factor = scale_factor
- else:
- self.register_buffer('scale_factor', torch.tensor(scale_factor))
- self.instantiate_first_stage(first_stage_config)
- self.instantiate_cond_stage(cond_stage_config)
- self.cond_stage_forward = cond_stage_forward
- self.clip_denoised = False
- self.bbox_tokenizer = None
-
- self.restarted_from_ckpt = False
- if ckpt_path is not None:
- self.init_from_ckpt(ckpt_path, ignore_keys)
- self.restarted_from_ckpt = True
-
- def make_cond_schedule(self, ):
- self.cond_ids = torch.full(size=(self.num_timesteps,), fill_value=self.num_timesteps - 1, dtype=torch.long)
- ids = torch.round(torch.linspace(0, self.num_timesteps - 1, self.num_timesteps_cond)).long()
- self.cond_ids[:self.num_timesteps_cond] = ids
-
- @rank_zero_only
- @torch.no_grad()
- def on_train_batch_start(self, batch, batch_idx, dataloader_idx):
- # only for very first batch
- if self.scale_by_std and self.current_epoch == 0 and self.global_step == 0 and batch_idx == 0 and not self.restarted_from_ckpt:
- assert self.scale_factor == 1., 'rather not use custom rescaling and std-rescaling simultaneously'
- # set rescale weight to 1./std of encodings
- print("### USING STD-RESCALING ###")
- x = super().get_input(batch, self.first_stage_key)
- x = x.to(self.device)
- encoder_posterior = self.encode_first_stage(x)
- z = self.get_first_stage_encoding(encoder_posterior).detach()
- del self.scale_factor
- self.register_buffer('scale_factor', 1. / z.flatten().std())
- print(f"setting self.scale_factor to {self.scale_factor}")
- print("### USING STD-RESCALING ###")
-
- def register_schedule(self,
- given_betas=None, beta_schedule="linear", timesteps=1000,
- linear_start=1e-4, linear_end=2e-2, cosine_s=8e-3):
- super().register_schedule(given_betas, beta_schedule, timesteps, linear_start, linear_end, cosine_s)
-
- self.shorten_cond_schedule = self.num_timesteps_cond > 1
- if self.shorten_cond_schedule:
- self.make_cond_schedule()
-
- def instantiate_first_stage(self, config):
- model = instantiate_from_config(config)
- self.first_stage_model = model.eval()
- self.first_stage_model.train = disabled_train
- for param in self.first_stage_model.parameters():
- param.requires_grad = False
-
- def instantiate_cond_stage(self, config):
- if not self.cond_stage_trainable:
- if config == "__is_first_stage__":
- print("Using first stage also as cond stage.")
- self.cond_stage_model = self.first_stage_model
- elif config == "__is_unconditional__":
- print(f"Training {self.__class__.__name__} as an unconditional model.")
- self.cond_stage_model = None
- # self.be_unconditional = True
- else:
- model = instantiate_from_config(config)
- self.cond_stage_model = model.eval()
- self.cond_stage_model.train = disabled_train
- for param in self.cond_stage_model.parameters():
- param.requires_grad = False
- else:
- assert config != '__is_first_stage__'
- assert config != '__is_unconditional__'
- model = instantiate_from_config(config)
- self.cond_stage_model = model
-
- def _get_denoise_row_from_list(self, samples, desc='', force_no_decoder_quantization=False):
- denoise_row = []
- for zd in tqdm(samples, desc=desc):
- denoise_row.append(self.decode_first_stage(zd.to(self.device),
- force_not_quantize=force_no_decoder_quantization))
- n_imgs_per_row = len(denoise_row)
- denoise_row = torch.stack(denoise_row) # n_log_step, n_row, C, H, W
- denoise_grid = rearrange(denoise_row, 'n b c h w -> b n c h w')
- denoise_grid = rearrange(denoise_grid, 'b n c h w -> (b n) c h w')
- denoise_grid = make_grid(denoise_grid, nrow=n_imgs_per_row)
- return denoise_grid
-
- def get_first_stage_encoding(self, encoder_posterior):
- if isinstance(encoder_posterior, DiagonalGaussianDistribution):
- z = encoder_posterior.sample()
- elif isinstance(encoder_posterior, torch.Tensor):
- z = encoder_posterior
- else:
- raise NotImplementedError(f"encoder_posterior of type '{type(encoder_posterior)}' not yet implemented")
- return self.scale_factor * z
-
- def get_learned_conditioning(self, c):
- if self.cond_stage_forward is None:
- if hasattr(self.cond_stage_model, 'encode') and callable(self.cond_stage_model.encode):
- c = self.cond_stage_model.encode(c)
- if isinstance(c, DiagonalGaussianDistribution):
- c = c.mode()
- else:
- c = self.cond_stage_model(c)
- else:
- assert hasattr(self.cond_stage_model, self.cond_stage_forward)
- c = getattr(self.cond_stage_model, self.cond_stage_forward)(c)
- return c
-
- def meshgrid(self, h, w):
- y = torch.arange(0, h).view(h, 1, 1).repeat(1, w, 1)
- x = torch.arange(0, w).view(1, w, 1).repeat(h, 1, 1)
-
- arr = torch.cat([y, x], dim=-1)
- return arr
-
- def delta_border(self, h, w):
- """
- :param h: height
- :param w: width
- :return: normalized distance to image border,
- wtith min distance = 0 at border and max dist = 0.5 at image center
- """
- lower_right_corner = torch.tensor([h - 1, w - 1]).view(1, 1, 2)
- arr = self.meshgrid(h, w) / lower_right_corner
- dist_left_up = torch.min(arr, dim=-1, keepdims=True)[0]
- dist_right_down = torch.min(1 - arr, dim=-1, keepdims=True)[0]
- edge_dist = torch.min(torch.cat([dist_left_up, dist_right_down], dim=-1), dim=-1)[0]
- return edge_dist
-
- def get_weighting(self, h, w, Ly, Lx, device):
- weighting = self.delta_border(h, w)
- weighting = torch.clip(weighting, self.split_input_params["clip_min_weight"],
- self.split_input_params["clip_max_weight"], )
- weighting = weighting.view(1, h * w, 1).repeat(1, 1, Ly * Lx).to(device)
-
- if self.split_input_params["tie_braker"]:
- L_weighting = self.delta_border(Ly, Lx)
- L_weighting = torch.clip(L_weighting,
- self.split_input_params["clip_min_tie_weight"],
- self.split_input_params["clip_max_tie_weight"])
-
- L_weighting = L_weighting.view(1, 1, Ly * Lx).to(device)
- weighting = weighting * L_weighting
- return weighting
-
- def get_fold_unfold(self, x, kernel_size, stride, uf=1, df=1): # todo load once not every time, shorten code
- """
- :param x: img of size (bs, c, h, w)
- :return: n img crops of size (n, bs, c, kernel_size[0], kernel_size[1])
- """
- bs, nc, h, w = x.shape
-
- # number of crops in image
- Ly = (h - kernel_size[0]) // stride[0] + 1
- Lx = (w - kernel_size[1]) // stride[1] + 1
-
- if uf == 1 and df == 1:
- fold_params = dict(kernel_size=kernel_size, dilation=1, padding=0, stride=stride)
- unfold = torch.nn.Unfold(**fold_params)
-
- fold = torch.nn.Fold(output_size=x.shape[2:], **fold_params)
-
- weighting = self.get_weighting(kernel_size[0], kernel_size[1], Ly, Lx, x.device).to(x.dtype)
- normalization = fold(weighting).view(1, 1, h, w) # normalizes the overlap
- weighting = weighting.view((1, 1, kernel_size[0], kernel_size[1], Ly * Lx))
-
- elif uf > 1 and df == 1:
- fold_params = dict(kernel_size=kernel_size, dilation=1, padding=0, stride=stride)
- unfold = torch.nn.Unfold(**fold_params)
-
- fold_params2 = dict(kernel_size=(kernel_size[0] * uf, kernel_size[0] * uf),
- dilation=1, padding=0,
- stride=(stride[0] * uf, stride[1] * uf))
- fold = torch.nn.Fold(output_size=(x.shape[2] * uf, x.shape[3] * uf), **fold_params2)
-
- weighting = self.get_weighting(kernel_size[0] * uf, kernel_size[1] * uf, Ly, Lx, x.device).to(x.dtype)
- normalization = fold(weighting).view(1, 1, h * uf, w * uf) # normalizes the overlap
- weighting = weighting.view((1, 1, kernel_size[0] * uf, kernel_size[1] * uf, Ly * Lx))
-
- elif df > 1 and uf == 1:
- fold_params = dict(kernel_size=kernel_size, dilation=1, padding=0, stride=stride)
- unfold = torch.nn.Unfold(**fold_params)
-
- fold_params2 = dict(kernel_size=(kernel_size[0] // df, kernel_size[0] // df),
- dilation=1, padding=0,
- stride=(stride[0] // df, stride[1] // df))
- fold = torch.nn.Fold(output_size=(x.shape[2] // df, x.shape[3] // df), **fold_params2)
-
- weighting = self.get_weighting(kernel_size[0] // df, kernel_size[1] // df, Ly, Lx, x.device).to(x.dtype)
- normalization = fold(weighting).view(1, 1, h // df, w // df) # normalizes the overlap
- weighting = weighting.view((1, 1, kernel_size[0] // df, kernel_size[1] // df, Ly * Lx))
-
- else:
- raise NotImplementedError
-
- return fold, unfold, normalization, weighting
-
- @torch.no_grad()
- def get_input(self, batch, k, return_first_stage_outputs=False, force_c_encode=False,
- cond_key=None, return_original_cond=False, bs=None):
- x = super().get_input(batch, k)
- if bs is not None:
- x = x[:bs]
- x = x.to(self.device)
- encoder_posterior = self.encode_first_stage(x)
- z = self.get_first_stage_encoding(encoder_posterior).detach()
-
- if self.model.conditioning_key is not None:
- if cond_key is None:
- cond_key = self.cond_stage_key
- if cond_key != self.first_stage_key:
- if cond_key in ['caption', 'coordinates_bbox']:
- xc = batch[cond_key]
- elif cond_key == 'class_label':
- xc = batch
- else:
- xc = super().get_input(batch, cond_key).to(self.device)
- else:
- xc = x
- if not self.cond_stage_trainable or force_c_encode:
- if isinstance(xc, dict) or isinstance(xc, list):
- # import pudb; pudb.set_trace()
- c = self.get_learned_conditioning(xc)
- else:
- c = self.get_learned_conditioning(xc.to(self.device))
- else:
- c = xc
- if bs is not None:
- c = c[:bs]
-
- if self.use_positional_encodings:
- pos_x, pos_y = self.compute_latent_shifts(batch)
- ckey = __conditioning_keys__[self.model.conditioning_key]
- c = {ckey: c, 'pos_x': pos_x, 'pos_y': pos_y}
-
- else:
- c = None
- xc = None
- if self.use_positional_encodings:
- pos_x, pos_y = self.compute_latent_shifts(batch)
- c = {'pos_x': pos_x, 'pos_y': pos_y}
- out = [z, c]
- if return_first_stage_outputs:
- xrec = self.decode_first_stage(z)
- out.extend([x, xrec])
- if return_original_cond:
- out.append(xc)
- return out
-
- @torch.no_grad()
- def decode_first_stage(self, z, predict_cids=False, force_not_quantize=False):
- if predict_cids:
- if z.dim() == 4:
- z = torch.argmax(z.exp(), dim=1).long()
- z = self.first_stage_model.quantize.get_codebook_entry(z, shape=None)
- z = rearrange(z, 'b h w c -> b c h w').contiguous()
-
- z = 1. / self.scale_factor * z
-
- if hasattr(self, "split_input_params"):
- if self.split_input_params["patch_distributed_vq"]:
- ks = self.split_input_params["ks"] # eg. (128, 128)
- stride = self.split_input_params["stride"] # eg. (64, 64)
- uf = self.split_input_params["vqf"]
- bs, nc, h, w = z.shape
- if ks[0] > h or ks[1] > w:
- ks = (min(ks[0], h), min(ks[1], w))
- print("reducing Kernel")
-
- if stride[0] > h or stride[1] > w:
- stride = (min(stride[0], h), min(stride[1], w))
- print("reducing stride")
-
- fold, unfold, normalization, weighting = self.get_fold_unfold(z, ks, stride, uf=uf)
-
- z = unfold(z) # (bn, nc * prod(**ks), L)
- # 1. Reshape to img shape
- z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) # (bn, nc, ks[0], ks[1], L )
-
- # 2. apply model loop over last dim
- if isinstance(self.first_stage_model, VQModelInterface):
- output_list = [self.first_stage_model.decode(z[:, :, :, :, i],
- force_not_quantize=predict_cids or force_not_quantize)
- for i in range(z.shape[-1])]
- else:
-
- output_list = [self.first_stage_model.decode(z[:, :, :, :, i])
- for i in range(z.shape[-1])]
-
- o = torch.stack(output_list, axis=-1) # # (bn, nc, ks[0], ks[1], L)
- o = o * weighting
- # Reverse 1. reshape to img shape
- o = o.view((o.shape[0], -1, o.shape[-1])) # (bn, nc * ks[0] * ks[1], L)
- # stitch crops together
- decoded = fold(o)
- decoded = decoded / normalization # norm is shape (1, 1, h, w)
- return decoded
- else:
- if isinstance(self.first_stage_model, VQModelInterface):
- return self.first_stage_model.decode(z, force_not_quantize=predict_cids or force_not_quantize)
- else:
- return self.first_stage_model.decode(z)
-
- else:
- if isinstance(self.first_stage_model, VQModelInterface):
- return self.first_stage_model.decode(z, force_not_quantize=predict_cids or force_not_quantize)
- else:
- return self.first_stage_model.decode(z)
-
- # same as above but without decorator
- def differentiable_decode_first_stage(self, z, predict_cids=False, force_not_quantize=False):
- if predict_cids:
- if z.dim() == 4:
- z = torch.argmax(z.exp(), dim=1).long()
- z = self.first_stage_model.quantize.get_codebook_entry(z, shape=None)
- z = rearrange(z, 'b h w c -> b c h w').contiguous()
-
- z = 1. / self.scale_factor * z
-
- if hasattr(self, "split_input_params"):
- if self.split_input_params["patch_distributed_vq"]:
- ks = self.split_input_params["ks"] # eg. (128, 128)
- stride = self.split_input_params["stride"] # eg. (64, 64)
- uf = self.split_input_params["vqf"]
- bs, nc, h, w = z.shape
- if ks[0] > h or ks[1] > w:
- ks = (min(ks[0], h), min(ks[1], w))
- print("reducing Kernel")
-
- if stride[0] > h or stride[1] > w:
- stride = (min(stride[0], h), min(stride[1], w))
- print("reducing stride")
-
- fold, unfold, normalization, weighting = self.get_fold_unfold(z, ks, stride, uf=uf)
-
- z = unfold(z) # (bn, nc * prod(**ks), L)
- # 1. Reshape to img shape
- z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) # (bn, nc, ks[0], ks[1], L )
-
- # 2. apply model loop over last dim
- if isinstance(self.first_stage_model, VQModelInterface):
- output_list = [self.first_stage_model.decode(z[:, :, :, :, i],
- force_not_quantize=predict_cids or force_not_quantize)
- for i in range(z.shape[-1])]
- else:
-
- output_list = [self.first_stage_model.decode(z[:, :, :, :, i])
- for i in range(z.shape[-1])]
-
- o = torch.stack(output_list, axis=-1) # # (bn, nc, ks[0], ks[1], L)
- o = o * weighting
- # Reverse 1. reshape to img shape
- o = o.view((o.shape[0], -1, o.shape[-1])) # (bn, nc * ks[0] * ks[1], L)
- # stitch crops together
- decoded = fold(o)
- decoded = decoded / normalization # norm is shape (1, 1, h, w)
- return decoded
- else:
- if isinstance(self.first_stage_model, VQModelInterface):
- return self.first_stage_model.decode(z, force_not_quantize=predict_cids or force_not_quantize)
- else:
- return self.first_stage_model.decode(z)
-
- else:
- if isinstance(self.first_stage_model, VQModelInterface):
- return self.first_stage_model.decode(z, force_not_quantize=predict_cids or force_not_quantize)
- else:
- return self.first_stage_model.decode(z)
-
- @torch.no_grad()
- def encode_first_stage(self, x):
- if hasattr(self, "split_input_params"):
- if self.split_input_params["patch_distributed_vq"]:
- ks = self.split_input_params["ks"] # eg. (128, 128)
- stride = self.split_input_params["stride"] # eg. (64, 64)
- df = self.split_input_params["vqf"]
- self.split_input_params['original_image_size'] = x.shape[-2:]
- bs, nc, h, w = x.shape
- if ks[0] > h or ks[1] > w:
- ks = (min(ks[0], h), min(ks[1], w))
- print("reducing Kernel")
-
- if stride[0] > h or stride[1] > w:
- stride = (min(stride[0], h), min(stride[1], w))
- print("reducing stride")
-
- fold, unfold, normalization, weighting = self.get_fold_unfold(x, ks, stride, df=df)
- z = unfold(x) # (bn, nc * prod(**ks), L)
- # Reshape to img shape
- z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) # (bn, nc, ks[0], ks[1], L )
-
- output_list = [self.first_stage_model.encode(z[:, :, :, :, i])
- for i in range(z.shape[-1])]
-
- o = torch.stack(output_list, axis=-1)
- o = o * weighting
-
- # Reverse reshape to img shape
- o = o.view((o.shape[0], -1, o.shape[-1])) # (bn, nc * ks[0] * ks[1], L)
- # stitch crops together
- decoded = fold(o)
- decoded = decoded / normalization
- return decoded
-
- else:
- return self.first_stage_model.encode(x)
- else:
- return self.first_stage_model.encode(x)
-
- def shared_step(self, batch, **kwargs):
- x, c = self.get_input(batch, self.first_stage_key)
- loss = self(x, c)
- return loss
-
- def forward(self, x, c, *args, **kwargs):
- t = torch.randint(0, self.num_timesteps, (x.shape[0],), device=self.device).long()
- if self.model.conditioning_key is not None:
- assert c is not None
- if self.cond_stage_trainable:
- c = self.get_learned_conditioning(c)
- if self.shorten_cond_schedule: # TODO: drop this option
- tc = self.cond_ids[t].to(self.device)
- c = self.q_sample(x_start=c, t=tc, noise=torch.randn_like(c.float()))
- return self.p_losses(x, c, t, *args, **kwargs)
-
- def _rescale_annotations(self, bboxes, crop_coordinates): # TODO: move to dataset
- def rescale_bbox(bbox):
- x0 = clamp((bbox[0] - crop_coordinates[0]) / crop_coordinates[2])
- y0 = clamp((bbox[1] - crop_coordinates[1]) / crop_coordinates[3])
- w = min(bbox[2] / crop_coordinates[2], 1 - x0)
- h = min(bbox[3] / crop_coordinates[3], 1 - y0)
- return x0, y0, w, h
-
- return [rescale_bbox(b) for b in bboxes]
-
- def apply_model(self, x_noisy, t, cond, return_ids=False):
-
- if isinstance(cond, dict):
- # hybrid case, cond is exptected to be a dict
- pass
- else:
- if not isinstance(cond, list):
- cond = [cond]
- key = 'c_concat' if self.model.conditioning_key == 'concat' else 'c_crossattn'
- cond = {key: cond}
-
- if hasattr(self, "split_input_params"):
- assert len(cond) == 1 # todo can only deal with one conditioning atm
- assert not return_ids
- ks = self.split_input_params["ks"] # eg. (128, 128)
- stride = self.split_input_params["stride"] # eg. (64, 64)
-
- h, w = x_noisy.shape[-2:]
-
- fold, unfold, normalization, weighting = self.get_fold_unfold(x_noisy, ks, stride)
-
- z = unfold(x_noisy) # (bn, nc * prod(**ks), L)
- # Reshape to img shape
- z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) # (bn, nc, ks[0], ks[1], L )
- z_list = [z[:, :, :, :, i] for i in range(z.shape[-1])]
-
- if self.cond_stage_key in ["image", "LR_image", "segmentation",
- 'bbox_img'] and self.model.conditioning_key: # todo check for completeness
- c_key = next(iter(cond.keys())) # get key
- c = next(iter(cond.values())) # get value
- assert (len(c) == 1) # todo extend to list with more than one elem
- c = c[0] # get element
-
- c = unfold(c)
- c = c.view((c.shape[0], -1, ks[0], ks[1], c.shape[-1])) # (bn, nc, ks[0], ks[1], L )
-
- cond_list = [{c_key: [c[:, :, :, :, i]]} for i in range(c.shape[-1])]
-
- elif self.cond_stage_key == 'coordinates_bbox':
- assert 'original_image_size' in self.split_input_params, 'BoudingBoxRescaling is missing original_image_size'
-
- # assuming padding of unfold is always 0 and its dilation is always 1
- n_patches_per_row = int((w - ks[0]) / stride[0] + 1)
- full_img_h, full_img_w = self.split_input_params['original_image_size']
- # as we are operating on latents, we need the factor from the original image size to the
- # spatial latent size to properly rescale the crops for regenerating the bbox annotations
- num_downs = self.first_stage_model.encoder.num_resolutions - 1
- rescale_latent = 2 ** (num_downs)
-
- # get top left postions of patches as conforming for the bbbox tokenizer, therefore we
- # need to rescale the tl patch coordinates to be in between (0,1)
- tl_patch_coordinates = [(rescale_latent * stride[0] * (patch_nr % n_patches_per_row) / full_img_w,
- rescale_latent * stride[1] * (patch_nr // n_patches_per_row) / full_img_h)
- for patch_nr in range(z.shape[-1])]
-
- # patch_limits are tl_coord, width and height coordinates as (x_tl, y_tl, h, w)
- patch_limits = [(x_tl, y_tl,
- rescale_latent * ks[0] / full_img_w,
- rescale_latent * ks[1] / full_img_h) for x_tl, y_tl in tl_patch_coordinates]
- # patch_values = [(np.arange(x_tl,min(x_tl+ks, 1.)),np.arange(y_tl,min(y_tl+ks, 1.))) for x_tl, y_tl in tl_patch_coordinates]
-
- # tokenize crop coordinates for the bounding boxes of the respective patches
- patch_limits_tknzd = [torch.LongTensor(self.bbox_tokenizer._crop_encoder(bbox))[None].to(self.device)
- for bbox in patch_limits] # list of length l with tensors of shape (1, 2)
- print(patch_limits_tknzd[0].shape)
- # cut tknzd crop position from conditioning
- assert isinstance(cond, dict), 'cond must be dict to be fed into model'
- cut_cond = cond['c_crossattn'][0][..., :-2].to(self.device)
- print(cut_cond.shape)
-
- adapted_cond = torch.stack([torch.cat([cut_cond, p], dim=1) for p in patch_limits_tknzd])
- adapted_cond = rearrange(adapted_cond, 'l b n -> (l b) n')
- print(adapted_cond.shape)
- adapted_cond = self.get_learned_conditioning(adapted_cond)
- print(adapted_cond.shape)
- adapted_cond = rearrange(adapted_cond, '(l b) n d -> l b n d', l=z.shape[-1])
- print(adapted_cond.shape)
-
- cond_list = [{'c_crossattn': [e]} for e in adapted_cond]
-
- else:
- cond_list = [cond for i in range(z.shape[-1])] # Todo make this more efficient
-
- # apply model by loop over crops
- output_list = [self.model(z_list[i], t, **cond_list[i]) for i in range(z.shape[-1])]
- assert not isinstance(output_list[0],
- tuple) # todo cant deal with multiple model outputs check this never happens
-
- o = torch.stack(output_list, axis=-1)
- o = o * weighting
- # Reverse reshape to img shape
- o = o.view((o.shape[0], -1, o.shape[-1])) # (bn, nc * ks[0] * ks[1], L)
- # stitch crops together
- x_recon = fold(o) / normalization
-
- else:
- x_recon = self.model(x_noisy, t, **cond)
-
- if isinstance(x_recon, tuple) and not return_ids:
- return x_recon[0]
- else:
- return x_recon
-
- def _predict_eps_from_xstart(self, x_t, t, pred_xstart):
- return (extract_into_tensor(self.sqrt_recip_alphas_cumprod, t, x_t.shape) * x_t - pred_xstart) / \
- extract_into_tensor(self.sqrt_recipm1_alphas_cumprod, t, x_t.shape)
-
- def _prior_bpd(self, x_start):
- """
- Get the prior KL term for the variational lower-bound, measured in
- bits-per-dim.
- This term can't be optimized, as it only depends on the encoder.
- :param x_start: the [N x C x ...] tensor of inputs.
- :return: a batch of [N] KL values (in bits), one per batch element.
- """
- batch_size = x_start.shape[0]
- t = torch.tensor([self.num_timesteps - 1] * batch_size, device=x_start.device)
- qt_mean, _, qt_log_variance = self.q_mean_variance(x_start, t)
- kl_prior = normal_kl(mean1=qt_mean, logvar1=qt_log_variance, mean2=0.0, logvar2=0.0)
- return mean_flat(kl_prior) / np.log(2.0)
-
- def p_losses(self, x_start, cond, t, noise=None):
- noise = default(noise, lambda: torch.randn_like(x_start))
- x_noisy = self.q_sample(x_start=x_start, t=t, noise=noise)
- model_output = self.apply_model(x_noisy, t, cond)
-
- loss_dict = {}
- prefix = 'train' if self.training else 'val'
-
- if self.parameterization == "x0":
- target = x_start
- elif self.parameterization == "eps":
- target = noise
- else:
- raise NotImplementedError()
-
- loss_simple = self.get_loss(model_output, target, mean=False).mean([1, 2, 3])
- loss_dict.update({f'{prefix}/loss_simple': loss_simple.mean()})
-
- logvar_t = self.logvar[t].to(self.device)
- loss = loss_simple / torch.exp(logvar_t) + logvar_t
- # loss = loss_simple / torch.exp(self.logvar) + self.logvar
- if self.learn_logvar:
- loss_dict.update({f'{prefix}/loss_gamma': loss.mean()})
- loss_dict.update({'logvar': self.logvar.data.mean()})
-
- loss = self.l_simple_weight * loss.mean()
-
- loss_vlb = self.get_loss(model_output, target, mean=False).mean(dim=(1, 2, 3))
- loss_vlb = (self.lvlb_weights[t] * loss_vlb).mean()
- loss_dict.update({f'{prefix}/loss_vlb': loss_vlb})
- loss += (self.original_elbo_weight * loss_vlb)
- loss_dict.update({f'{prefix}/loss': loss})
-
- return loss, loss_dict
-
- def p_mean_variance(self, x, c, t, clip_denoised: bool, return_codebook_ids=False, quantize_denoised=False,
- return_x0=False, score_corrector=None, corrector_kwargs=None):
- t_in = t
- model_out = self.apply_model(x, t_in, c, return_ids=return_codebook_ids)
-
- if score_corrector is not None:
- assert self.parameterization == "eps"
- model_out = score_corrector.modify_score(self, model_out, x, t, c, **corrector_kwargs)
-
- if return_codebook_ids:
- model_out, logits = model_out
-
- if self.parameterization == "eps":
- x_recon = self.predict_start_from_noise(x, t=t, noise=model_out)
- elif self.parameterization == "x0":
- x_recon = model_out
- else:
- raise NotImplementedError()
-
- if clip_denoised:
- x_recon.clamp_(-1., 1.)
- if quantize_denoised:
- x_recon, _, [_, _, indices] = self.first_stage_model.quantize(x_recon)
- model_mean, posterior_variance, posterior_log_variance = self.q_posterior(x_start=x_recon, x_t=x, t=t)
- if return_codebook_ids:
- return model_mean, posterior_variance, posterior_log_variance, logits
- elif return_x0:
- return model_mean, posterior_variance, posterior_log_variance, x_recon
- else:
- return model_mean, posterior_variance, posterior_log_variance
-
- @torch.no_grad()
- def p_sample(self, x, c, t, clip_denoised=False, repeat_noise=False,
- return_codebook_ids=False, quantize_denoised=False, return_x0=False,
- temperature=1., noise_dropout=0., score_corrector=None, corrector_kwargs=None):
- b, *_, device = *x.shape, x.device
- outputs = self.p_mean_variance(x=x, c=c, t=t, clip_denoised=clip_denoised,
- return_codebook_ids=return_codebook_ids,
- quantize_denoised=quantize_denoised,
- return_x0=return_x0,
- score_corrector=score_corrector, corrector_kwargs=corrector_kwargs)
- if return_codebook_ids:
- raise DeprecationWarning("Support dropped.")
- model_mean, _, model_log_variance, logits = outputs
- elif return_x0:
- model_mean, _, model_log_variance, x0 = outputs
- else:
- model_mean, _, model_log_variance = outputs
-
- noise = noise_like(x.shape, device, repeat_noise) * temperature
- if noise_dropout > 0.:
- noise = torch.nn.functional.dropout(noise, p=noise_dropout)
- # no noise when t == 0
- nonzero_mask = (1 - (t == 0).float()).reshape(b, *((1,) * (len(x.shape) - 1)))
-
- if return_codebook_ids:
- return model_mean + nonzero_mask * (0.5 * model_log_variance).exp() * noise, logits.argmax(dim=1)
- if return_x0:
- return model_mean + nonzero_mask * (0.5 * model_log_variance).exp() * noise, x0
- else:
- return model_mean + nonzero_mask * (0.5 * model_log_variance).exp() * noise
-
- @torch.no_grad()
- def progressive_denoising(self, cond, shape, verbose=True, callback=None, quantize_denoised=False,
- img_callback=None, mask=None, x0=None, temperature=1., noise_dropout=0.,
- score_corrector=None, corrector_kwargs=None, batch_size=None, x_T=None, start_T=None,
- log_every_t=None):
- if not log_every_t:
- log_every_t = self.log_every_t
- timesteps = self.num_timesteps
- if batch_size is not None:
- b = batch_size if batch_size is not None else shape[0]
- shape = [batch_size] + list(shape)
- else:
- b = batch_size = shape[0]
- if x_T is None:
- img = torch.randn(shape, device=self.device)
- else:
- img = x_T
- intermediates = []
- if cond is not None:
- if isinstance(cond, dict):
- cond = {key: cond[key][:batch_size] if not isinstance(cond[key], list) else
- list(map(lambda x: x[:batch_size], cond[key])) for key in cond}
- else:
- cond = [c[:batch_size] for c in cond] if isinstance(cond, list) else cond[:batch_size]
-
- if start_T is not None:
- timesteps = min(timesteps, start_T)
- iterator = tqdm(reversed(range(0, timesteps)), desc='Progressive Generation',
- total=timesteps) if verbose else reversed(
- range(0, timesteps))
- if type(temperature) == float:
- temperature = [temperature] * timesteps
-
- for i in iterator:
- ts = torch.full((b,), i, device=self.device, dtype=torch.long)
- if self.shorten_cond_schedule:
- assert self.model.conditioning_key != 'hybrid'
- tc = self.cond_ids[ts].to(cond.device)
- cond = self.q_sample(x_start=cond, t=tc, noise=torch.randn_like(cond))
-
- img, x0_partial = self.p_sample(img, cond, ts,
- clip_denoised=self.clip_denoised,
- quantize_denoised=quantize_denoised, return_x0=True,
- temperature=temperature[i], noise_dropout=noise_dropout,
- score_corrector=score_corrector, corrector_kwargs=corrector_kwargs)
- if mask is not None:
- assert x0 is not None
- img_orig = self.q_sample(x0, ts)
- img = img_orig * mask + (1. - mask) * img
-
- if i % log_every_t == 0 or i == timesteps - 1:
- intermediates.append(x0_partial)
- if callback: callback(i)
- if img_callback: img_callback(img, i)
- return img, intermediates
-
- @torch.no_grad()
- def p_sample_loop(self, cond, shape, return_intermediates=False,
- x_T=None, verbose=True, callback=None, timesteps=None, quantize_denoised=False,
- mask=None, x0=None, img_callback=None, start_T=None,
- log_every_t=None):
-
- if not log_every_t:
- log_every_t = self.log_every_t
- device = self.betas.device
- b = shape[0]
- if x_T is None:
- img = torch.randn(shape, device=device)
- else:
- img = x_T
-
- intermediates = [img]
- if timesteps is None:
- timesteps = self.num_timesteps
-
- if start_T is not None:
- timesteps = min(timesteps, start_T)
- iterator = tqdm(reversed(range(0, timesteps)), desc='Sampling t', total=timesteps) if verbose else reversed(
- range(0, timesteps))
-
- if mask is not None:
- assert x0 is not None
- assert x0.shape[2:3] == mask.shape[2:3] # spatial size has to match
-
- for i in iterator:
- ts = torch.full((b,), i, device=device, dtype=torch.long)
- if self.shorten_cond_schedule:
- assert self.model.conditioning_key != 'hybrid'
- tc = self.cond_ids[ts].to(cond.device)
- cond = self.q_sample(x_start=cond, t=tc, noise=torch.randn_like(cond))
-
- img = self.p_sample(img, cond, ts,
- clip_denoised=self.clip_denoised,
- quantize_denoised=quantize_denoised)
- if mask is not None:
- img_orig = self.q_sample(x0, ts)
- img = img_orig * mask + (1. - mask) * img
-
- if i % log_every_t == 0 or i == timesteps - 1:
- intermediates.append(img)
- if callback: callback(i)
- if img_callback: img_callback(img, i)
-
- if return_intermediates:
- return img, intermediates
- return img
-
- @torch.no_grad()
- def sample(self, cond, batch_size=16, return_intermediates=False, x_T=None,
- verbose=True, timesteps=None, quantize_denoised=False,
- mask=None, x0=None, shape=None,**kwargs):
- if shape is None:
- shape = (batch_size, self.channels, self.image_size, self.image_size)
- if cond is not None:
- if isinstance(cond, dict):
- cond = {key: cond[key][:batch_size] if not isinstance(cond[key], list) else
- list(map(lambda x: x[:batch_size], cond[key])) for key in cond}
- else:
- cond = [c[:batch_size] for c in cond] if isinstance(cond, list) else cond[:batch_size]
- return self.p_sample_loop(cond,
- shape,
- return_intermediates=return_intermediates, x_T=x_T,
- verbose=verbose, timesteps=timesteps, quantize_denoised=quantize_denoised,
- mask=mask, x0=x0)
-
- @torch.no_grad()
- def sample_log(self,cond,batch_size,ddim, ddim_steps,**kwargs):
-
- if ddim:
- ddim_sampler = DDIMSampler(self)
- shape = (self.channels, self.image_size, self.image_size)
- samples, intermediates =ddim_sampler.sample(ddim_steps,batch_size,
- shape,cond,verbose=False,**kwargs)
-
- else:
- samples, intermediates = self.sample(cond=cond, batch_size=batch_size,
- return_intermediates=True,**kwargs)
-
- return samples, intermediates
-
-
- @torch.no_grad()
- def log_images(self, batch, N=8, n_row=4, sample=True, ddim_steps=200, ddim_eta=1., return_keys=None,
- quantize_denoised=True, inpaint=True, plot_denoise_rows=False, plot_progressive_rows=True,
- plot_diffusion_rows=True, **kwargs):
-
- use_ddim = ddim_steps is not None
-
- log = dict()
- z, c, x, xrec, xc = self.get_input(batch, self.first_stage_key,
- return_first_stage_outputs=True,
- force_c_encode=True,
- return_original_cond=True,
- bs=N)
- N = min(x.shape[0], N)
- n_row = min(x.shape[0], n_row)
- log["inputs"] = x
- log["reconstruction"] = xrec
- if self.model.conditioning_key is not None:
- if hasattr(self.cond_stage_model, "decode"):
- xc = self.cond_stage_model.decode(c)
- log["conditioning"] = xc
- elif self.cond_stage_key in ["caption"]:
- xc = log_txt_as_img((x.shape[2], x.shape[3]), batch["caption"])
- log["conditioning"] = xc
- elif self.cond_stage_key == 'class_label':
- xc = log_txt_as_img((x.shape[2], x.shape[3]), batch["human_label"])
- log['conditioning'] = xc
- elif isimage(xc):
- log["conditioning"] = xc
- if ismap(xc):
- log["original_conditioning"] = self.to_rgb(xc)
-
- if plot_diffusion_rows:
- # get diffusion row
- diffusion_row = list()
- z_start = z[:n_row]
- for t in range(self.num_timesteps):
- if t % self.log_every_t == 0 or t == self.num_timesteps - 1:
- t = repeat(torch.tensor([t]), '1 -> b', b=n_row)
- t = t.to(self.device).long()
- noise = torch.randn_like(z_start)
- z_noisy = self.q_sample(x_start=z_start, t=t, noise=noise)
- diffusion_row.append(self.decode_first_stage(z_noisy))
-
- diffusion_row = torch.stack(diffusion_row) # n_log_step, n_row, C, H, W
- diffusion_grid = rearrange(diffusion_row, 'n b c h w -> b n c h w')
- diffusion_grid = rearrange(diffusion_grid, 'b n c h w -> (b n) c h w')
- diffusion_grid = make_grid(diffusion_grid, nrow=diffusion_row.shape[0])
- log["diffusion_row"] = diffusion_grid
-
- if sample:
- # get denoise row
- with self.ema_scope("Plotting"):
- samples, z_denoise_row = self.sample_log(cond=c,batch_size=N,ddim=use_ddim,
- ddim_steps=ddim_steps,eta=ddim_eta)
- # samples, z_denoise_row = self.sample(cond=c, batch_size=N, return_intermediates=True)
- x_samples = self.decode_first_stage(samples)
- log["samples"] = x_samples
- if plot_denoise_rows:
- denoise_grid = self._get_denoise_row_from_list(z_denoise_row)
- log["denoise_row"] = denoise_grid
-
- if quantize_denoised and not isinstance(self.first_stage_model, AutoencoderKL) and not isinstance(
- self.first_stage_model, IdentityFirstStage):
- # also display when quantizing x0 while sampling
- with self.ema_scope("Plotting Quantized Denoised"):
- samples, z_denoise_row = self.sample_log(cond=c,batch_size=N,ddim=use_ddim,
- ddim_steps=ddim_steps,eta=ddim_eta,
- quantize_denoised=True)
- # samples, z_denoise_row = self.sample(cond=c, batch_size=N, return_intermediates=True,
- # quantize_denoised=True)
- x_samples = self.decode_first_stage(samples.to(self.device))
- log["samples_x0_quantized"] = x_samples
-
- if inpaint:
- # make a simple center square
- b, h, w = z.shape[0], z.shape[2], z.shape[3]
- mask = torch.ones(N, h, w).to(self.device)
- # zeros will be filled in
- mask[:, h // 4:3 * h // 4, w // 4:3 * w // 4] = 0.
- mask = mask[:, None, ...]
- with self.ema_scope("Plotting Inpaint"):
-
- samples, _ = self.sample_log(cond=c,batch_size=N,ddim=use_ddim, eta=ddim_eta,
- ddim_steps=ddim_steps, x0=z[:N], mask=mask)
- x_samples = self.decode_first_stage(samples.to(self.device))
- log["samples_inpainting"] = x_samples
- log["mask"] = mask
-
- # outpaint
- with self.ema_scope("Plotting Outpaint"):
- samples, _ = self.sample_log(cond=c, batch_size=N, ddim=use_ddim,eta=ddim_eta,
- ddim_steps=ddim_steps, x0=z[:N], mask=mask)
- x_samples = self.decode_first_stage(samples.to(self.device))
- log["samples_outpainting"] = x_samples
-
- if plot_progressive_rows:
- with self.ema_scope("Plotting Progressives"):
- img, progressives = self.progressive_denoising(c,
- shape=(self.channels, self.image_size, self.image_size),
- batch_size=N)
- prog_row = self._get_denoise_row_from_list(progressives, desc="Progressive Generation")
- log["progressive_row"] = prog_row
-
- if return_keys:
- if np.intersect1d(list(log.keys()), return_keys).shape[0] == 0:
- return log
- else:
- return {key: log[key] for key in return_keys}
- return log
-
- def configure_optimizers(self):
- lr = self.learning_rate
- params = list(self.model.parameters())
- if self.cond_stage_trainable:
- print(f"{self.__class__.__name__}: Also optimizing conditioner params!")
- params = params + list(self.cond_stage_model.parameters())
- if self.learn_logvar:
- print('Diffusion model optimizing logvar')
- params.append(self.logvar)
- opt = torch.optim.AdamW(params, lr=lr)
- if self.use_scheduler:
- assert 'target' in self.scheduler_config
- scheduler = instantiate_from_config(self.scheduler_config)
-
- print("Setting up LambdaLR scheduler...")
- scheduler = [
- {
- 'scheduler': LambdaLR(opt, lr_lambda=scheduler.schedule),
- 'interval': 'step',
- 'frequency': 1
- }]
- return [opt], scheduler
- return opt
-
- @torch.no_grad()
- def to_rgb(self, x):
- x = x.float()
- if not hasattr(self, "colorize"):
- self.colorize = torch.randn(3, x.shape[1], 1, 1).to(x)
- x = nn.functional.conv2d(x, weight=self.colorize)
- x = 2. * (x - x.min()) / (x.max() - x.min()) - 1.
- return x
-
-
-class DiffusionWrapper(pl.LightningModule):
- def __init__(self, diff_model_config, conditioning_key):
- super().__init__()
- self.diffusion_model = instantiate_from_config(diff_model_config)
- self.conditioning_key = conditioning_key
- assert self.conditioning_key in [None, 'concat', 'crossattn', 'hybrid', 'adm']
-
- def forward(self, x, t, c_concat: list = None, c_crossattn: list = None):
- if self.conditioning_key is None:
- out = self.diffusion_model(x, t)
- elif self.conditioning_key == 'concat':
- xc = torch.cat([x] + c_concat, dim=1)
- out = self.diffusion_model(xc, t)
- elif self.conditioning_key == 'crossattn':
- cc = torch.cat(c_crossattn, 1)
- out = self.diffusion_model(x, t, context=cc)
- elif self.conditioning_key == 'hybrid':
- xc = torch.cat([x] + c_concat, dim=1)
- cc = torch.cat(c_crossattn, 1)
- out = self.diffusion_model(xc, t, context=cc)
- elif self.conditioning_key == 'adm':
- cc = c_crossattn[0]
- out = self.diffusion_model(x, t, y=cc)
- else:
- raise NotImplementedError()
-
- return out
-
-
-class Layout2ImgDiffusion(LatentDiffusion):
- # TODO: move all layout-specific hacks to this class
- def __init__(self, cond_stage_key, *args, **kwargs):
- assert cond_stage_key == 'coordinates_bbox', 'Layout2ImgDiffusion only for cond_stage_key="coordinates_bbox"'
- super().__init__(cond_stage_key=cond_stage_key, *args, **kwargs)
-
- def log_images(self, batch, N=8, *args, **kwargs):
- logs = super().log_images(batch=batch, N=N, *args, **kwargs)
-
- key = 'train' if self.training else 'validation'
- dset = self.trainer.datamodule.datasets[key]
- mapper = dset.conditional_builders[self.cond_stage_key]
-
- bbox_imgs = []
- map_fn = lambda catno: dset.get_textual_label(dset.get_category_id(catno))
- for tknzd_bbox in batch[self.cond_stage_key][:N]:
- bboximg = mapper.plot(tknzd_bbox.detach().cpu(), map_fn, (256, 256))
- bbox_imgs.append(bboximg)
-
- cond_img = torch.stack(bbox_imgs, dim=0)
- logs['bbox_image'] = cond_img
- return logs