| | """ |
| | 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 os |
| | 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 |
| |
|
| | try: |
| | from pytorch_lightning.utilities.distributed import rank_zero_only |
| | except: |
| | from pytorch_lightning.utilities.rank_zero import rank_zero_only |
| |
|
| | import bitsandbytes as bnb |
| |
|
| |
|
| | 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 |
| | |
| | |
| | from torchvision import transforms |
| |
|
| |
|
| | __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): |
| | |
| | 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=0.0, |
| | v_posterior=0.0, |
| | l_simple_weight=1.0, |
| | conditioning_key=None, |
| | parameterization="eps", |
| | scheduler_config=None, |
| | use_positional_encodings=False, |
| | learn_logvar=False, |
| | logvar_init=0.0, |
| | ): |
| | 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 |
| | 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 = 1.0 - betas |
| | alphas_cumprod = np.cumprod(alphas, axis=0) |
| | alphas_cumprod_prev = np.append(1.0, 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)) |
| |
|
| | |
| | self.register_buffer("sqrt_alphas_cumprod", to_torch(np.sqrt(alphas_cumprod))) |
| | self.register_buffer("sqrt_one_minus_alphas_cumprod", to_torch(np.sqrt(1.0 - alphas_cumprod))) |
| | self.register_buffer("log_one_minus_alphas_cumprod", to_torch(np.log(1.0 - alphas_cumprod))) |
| | self.register_buffer("sqrt_recip_alphas_cumprod", to_torch(np.sqrt(1.0 / alphas_cumprod))) |
| | self.register_buffer("sqrt_recipm1_alphas_cumprod", to_torch(np.sqrt(1.0 / alphas_cumprod - 1))) |
| |
|
| | |
| | posterior_variance = (1 - self.v_posterior) * betas * (1.0 - alphas_cumprod_prev) / ( |
| | 1.0 - alphas_cumprod |
| | ) + self.v_posterior * betas |
| | |
| | self.register_buffer("posterior_variance", to_torch(posterior_variance)) |
| | |
| | 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) / (1.0 - alphas_cumprod)), |
| | ) |
| | self.register_buffer( |
| | "posterior_mean_coef2", |
| | to_torch((1.0 - alphas_cumprod_prev) * np.sqrt(alphas) / (1.0 - 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)) / (2.0 * 1 - torch.Tensor(alphas_cumprod)) |
| | else: |
| | raise NotImplementedError("mu not supported") |
| | |
| | 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_(-1.0, 1.0) |
| |
|
| | 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) |
| | |
| | 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): |
| | |
| | |
| | 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 |
| |
|
| | |
| | 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: |
| | |
| | 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, |
| | x_feat_extracted=False, |
| | x_feat_key = "vae_feat", |
| | *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"] |
| | |
| | if conditioning_key is None: |
| | conditioning_key = "concat" if concat_mode else "crossattn" |
| | |
| | |
| | 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 |
| |
|
| | |
| | self.x_feat_extracted=x_feat_extracted |
| | self.x_feat_key = x_feat_key |
| | |
| |
|
| |
|
| | 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=None): |
| | |
| | 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 == 1.0, "rather not use custom rescaling and std-rescaling simultaneously" |
| | |
| | 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", 1.0 / 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 |
| | |
| | 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) |
| | 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): |
| | """ |
| | :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 |
| |
|
| | |
| | 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) |
| | 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) |
| | 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) |
| | 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, |
| | ): |
| | |
| | if self.x_feat_extracted and self.x_feat_key == "vae_feat": |
| | z = batch[self.x_feat_key].to(self.device) |
| | if bs is not None: |
| | z = z[:bs] |
| | x = None |
| |
|
| | elif self.x_feat_key == "ssl_feat": |
| | with torch.no_grad(): |
| | z = self.first_stage_model(batch) |
| |
|
| | z *= self.scale_factor |
| |
|
| | if bs is not None: |
| | z = z[:bs] |
| | x = None |
| | |
| | else: |
| |
|
| | 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", "mag"]: |
| | xc = batch[cond_key] |
| | elif cond_key in ["class_label", "hybrid"]: |
| | xc = batch |
| | else: |
| | xc = super().get_input(batch, cond_key).to(self.device) |
| | else: |
| | xc = x |
| | if cond_key != "mag" and (not self.cond_stage_trainable or force_c_encode): |
| | if isinstance(xc, dict) or isinstance(xc, list): |
| | c = self.get_learned_conditioning(xc) |
| | else: |
| | c = self.get_learned_conditioning(xc.to(self.device)) |
| | else: |
| | c = xc |
| | if bs is not None: |
| | if isinstance(c, list): |
| | c[0] = c[0][:bs] |
| | c[1] = c[1][:bs] |
| |
|
| | 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 = 1.0 / self.scale_factor * z |
| |
|
| | if hasattr(self, "split_input_params"): |
| | if self.split_input_params["patch_distributed_vq"]: |
| | ks = self.split_input_params["ks"] |
| | stride = self.split_input_params["stride"] |
| | 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) |
| | |
| | z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) |
| |
|
| | |
| | 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) |
| | o = o * weighting |
| | |
| | o = o.view((o.shape[0], -1, o.shape[-1])) |
| | |
| | decoded = fold(o) |
| | decoded = decoded / normalization |
| | 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) |
| |
|
| | |
| | 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 = 1.0 / self.scale_factor * z |
| |
|
| | if hasattr(self, "split_input_params"): |
| | if self.split_input_params["patch_distributed_vq"]: |
| | ks = self.split_input_params["ks"] |
| | stride = self.split_input_params["stride"] |
| | 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) |
| | |
| | z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) |
| |
|
| | |
| | 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) |
| | o = o * weighting |
| | |
| | o = o.view((o.shape[0], -1, o.shape[-1])) |
| | |
| | decoded = fold(o) |
| | decoded = decoded / normalization |
| | 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"] |
| | stride = self.split_input_params["stride"] |
| | 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) |
| | |
| | z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) |
| |
|
| | 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 |
| |
|
| | |
| | o = o.view((o.shape[0], -1, o.shape[-1])) |
| | |
| | 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) |
| | if self.model.conditioning_key == 'hybrid': |
| | c_concat = rearrange(batch["LR_image"], 'n h w c -> n c h w') |
| | kwargs["c_concat"] = [c_concat] |
| | loss = self(x, c, **kwargs) |
| | 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: |
| | 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 apply_model(self, x_noisy, t, cond, return_ids=False, **kwargs): |
| | if isinstance(cond, 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 |
| | assert not return_ids |
| | ks = self.split_input_params["ks"] |
| | stride = self.split_input_params["stride"] |
| |
|
| | h, w = x_noisy.shape[-2:] |
| |
|
| | fold, unfold, normalization, weighting = self.get_fold_unfold(x_noisy, ks, stride) |
| |
|
| | z = unfold(x_noisy) |
| | |
| | z = z.view((z.shape[0], -1, ks[0], ks[1], z.shape[-1])) |
| | 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 |
| | ): |
| | c_key = next(iter(cond.keys())) |
| | c = next(iter(cond.values())) |
| | assert len(c) == 1 |
| | c = c[0] |
| |
|
| | c = unfold(c) |
| | c = c.view((c.shape[0], -1, ks[0], ks[1], c.shape[-1])) |
| |
|
| | cond_list = [{c_key: [c[:, :, :, :, i]]} for i in range(c.shape[-1])] |
| |
|
| |
|
| | else: |
| | cond_list = [cond for i in range(z.shape[-1])] |
| |
|
| | |
| | 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 |
| | ) |
| |
|
| | o = torch.stack(output_list, axis=-1) |
| | o = o * weighting |
| | |
| | o = o.view((o.shape[0], -1, o.shape[-1])) |
| | |
| | x_recon = fold(o) / normalization |
| |
|
| | else: |
| | with torch.cuda.amp.autocast(): |
| | x_recon = self.model(x_noisy, t, **cond, **kwargs) |
| |
|
| | 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, **kwargs): |
| | 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, **kwargs) |
| |
|
| | 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() |
| |
|
| | dims_non_bs = tuple(range(1, target.dim())) |
| |
|
| | loss_simple = self.get_loss(model_output, target, mean=False).mean(dims_non_bs) |
| | loss_dict.update({f"{prefix}/loss_simple": loss_simple.mean()}) |
| |
|
| | self.logvar = self.logvar.to(self.device) |
| | logvar_t = self.logvar[t].to(self.device) |
| | loss = loss_simple / torch.exp(logvar_t) + logvar_t |
| | |
| | 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=dims_non_bs) |
| | 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_(-1.0, 1.0) |
| | 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=1.0, |
| | noise_dropout=0.0, |
| | 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 > 0.0: |
| | noise = torch.nn.functional.dropout(noise, p=noise_dropout) |
| | |
| | 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=1.0, |
| | noise_dropout=0.0, |
| | 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 + (1.0 - 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] |
| |
|
| | 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 + (1.0 - 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 get_images_and_latents(self, batch, **ddim_kwargs): |
| | """Returns input images, denoised images and latents for clustering""" |
| |
|
| | 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, |
| | ) |
| |
|
| | with self.ema_scope("Plotting"): |
| | samples_latent, _ = self.sample_log(cond=c, batch_size=x.shape[0], ddim=True, **ddim_kwargs) |
| |
|
| | convert_to_numpy = lambda x: x.detach().cpu().numpy() |
| |
|
| | x_samples = self.decode_first_stage(samples_latent) |
| | x_samples_ddim = torch.clamp((x_samples + 1.0) / 2.0, min=0.0, max=1.0) |
| | x_samples_ddim = (x_samples_ddim * 255).to(torch.uint8) |
| | x_samples_ddim = convert_to_numpy(x_samples_ddim) |
| |
|
| | input_arr = (127.5 * (x + 1)).detach().cpu().numpy().astype(np.uint8) |
| | samples_latent = convert_to_numpy(samples_latent) |
| |
|
| | return input_arr, x_samples_ddim, samples_latent |
| |
|
| | @torch.no_grad() |
| | def log_images( |
| | self, |
| | batch, |
| | N=8, |
| | n_row=4, |
| | sample=True, |
| | ddim_steps=200, |
| | ddim_eta=1.0, |
| | 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 in ["class_label", "hybrid"]: |
| | 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: |
| | |
| | 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) |
| | 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: |
| | |
| | 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, |
| | ) |
| | |
| | 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) |
| | ): |
| | |
| | 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, |
| | ) |
| | |
| | |
| | x_samples = self.decode_first_stage(samples.to(self.device)) |
| | log["samples_x0_quantized"] = x_samples |
| |
|
| | if inpaint: |
| | |
| | b, h, w = z.shape[0], z.shape[2], z.shape[3] |
| | mask = torch.ones(N, h, w).to(self.device) |
| | |
| | mask[:, h // 4 : 3 * h // 4, w // 4 : 3 * w // 4] = 0.0 |
| | 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 |
| |
|
| | |
| | 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 = 2.0 * (x - x.min()) / (x.max() - x.min()) - 1.0 |
| | 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 |
| |
|
| |
|