import argparse import math import os import numpy as np import toml import json import time from typing import Callable, Dict, List, Optional, Tuple, Union import torch from accelerate import Accelerator, PartialState from transformers import CLIPTextModel from tqdm import tqdm from PIL import Image from safetensors.torch import save_file from library import flux_models, flux_utils, strategy_base, train_util from library.device_utils import init_ipex, clean_memory_on_device from library.safetensors_utils import mem_eff_save_file init_ipex() from .utils import setup_logging setup_logging() import logging logger = logging.getLogger(__name__) # region sample images def sample_images( accelerator: Accelerator, args: argparse.Namespace, epoch, steps, flux, ae, text_encoders, sample_prompts_te_outputs, prompt_replacement=None, controlnet=None, ): if steps == 0: if not args.sample_at_first: return else: if args.sample_every_n_steps is None and args.sample_every_n_epochs is None: return if args.sample_every_n_epochs is not None: # sample_every_n_steps は無視する if epoch is None or epoch % args.sample_every_n_epochs != 0: return else: if steps % args.sample_every_n_steps != 0 or epoch is not None: # steps is not divisible or end of epoch return logger.info("") logger.info(f"generating sample images at step / サンプル画像生成 ステップ: {steps}") if not os.path.isfile(args.sample_prompts) and sample_prompts_te_outputs is None: logger.error(f"No prompt file / プロンプトファイルがありません: {args.sample_prompts}") return distributed_state = PartialState() # for multi gpu distributed inference. this is a singleton, so it's safe to use it here # unwrap unet and text_encoder(s) flux = accelerator.unwrap_model(flux) if text_encoders is not None: text_encoders = [(accelerator.unwrap_model(te) if te is not None else None) for te in text_encoders] if controlnet is not None: controlnet = accelerator.unwrap_model(controlnet) # print([(te.parameters().__next__().device if te is not None else None) for te in text_encoders]) prompts = train_util.load_prompts(args.sample_prompts) save_dir = args.output_dir + "/sample" os.makedirs(save_dir, exist_ok=True) # save random state to restore later rng_state = torch.get_rng_state() cuda_rng_state = None try: cuda_rng_state = torch.cuda.get_rng_state() if torch.cuda.is_available() else None except Exception: pass if distributed_state.num_processes <= 1: # If only one device is available, just use the original prompt list. We don't need to care about the distribution of prompts. with torch.no_grad(), accelerator.autocast(): for prompt_dict in prompts: sample_image_inference( accelerator, args, flux, text_encoders, ae, save_dir, prompt_dict, epoch, steps, sample_prompts_te_outputs, prompt_replacement, controlnet, ) else: # Creating list with N elements, where each element is a list of prompt_dicts, and N is the number of processes available (number of devices available) # prompt_dicts are assigned to lists based on order of processes, to attempt to time the image creation time to match enum order. Probably only works when steps and sampler are identical. per_process_prompts = [] # list of lists for i in range(distributed_state.num_processes): per_process_prompts.append(prompts[i :: distributed_state.num_processes]) with torch.no_grad(): with distributed_state.split_between_processes(per_process_prompts) as prompt_dict_lists: for prompt_dict in prompt_dict_lists[0]: sample_image_inference( accelerator, args, flux, text_encoders, ae, save_dir, prompt_dict, epoch, steps, sample_prompts_te_outputs, prompt_replacement, controlnet, ) torch.set_rng_state(rng_state) if cuda_rng_state is not None: torch.cuda.set_rng_state(cuda_rng_state) clean_memory_on_device(accelerator.device) def sample_image_inference( accelerator: Accelerator, args: argparse.Namespace, flux: flux_models.Flux, text_encoders: Optional[List[CLIPTextModel]], ae: flux_models.AutoEncoder, save_dir, prompt_dict, epoch, steps, sample_prompts_te_outputs, prompt_replacement, controlnet, ): assert isinstance(prompt_dict, dict) negative_prompt = prompt_dict.get("negative_prompt") sample_steps = prompt_dict.get("sample_steps", 20) width = prompt_dict.get("width", 512) height = prompt_dict.get("height", 512) emb_guidance_scale = prompt_dict.get("guidance_scale", 3.5) cfg_scale = prompt_dict.get("scale", 1.0) seed = prompt_dict.get("seed") controlnet_image = prompt_dict.get("controlnet_image") prompt: str = prompt_dict.get("prompt", "") # sampler_name: str = prompt_dict.get("sample_sampler", args.sample_sampler) if prompt_replacement is not None: prompt = prompt.replace(prompt_replacement[0], prompt_replacement[1]) if negative_prompt is not None: negative_prompt = negative_prompt.replace(prompt_replacement[0], prompt_replacement[1]) if seed is not None: torch.manual_seed(seed) torch.cuda.manual_seed(seed) else: # True random sample image generation torch.seed() torch.cuda.seed() if negative_prompt is None: negative_prompt = "" height = max(64, height - height % 16) # round to divisible by 16 width = max(64, width - width % 16) # round to divisible by 16 logger.info(f"prompt: {prompt}") if cfg_scale != 1.0: logger.info(f"negative_prompt: {negative_prompt}") elif negative_prompt != "": logger.info(f"negative prompt is ignored because scale is 1.0") logger.info(f"height: {height}") logger.info(f"width: {width}") logger.info(f"sample_steps: {sample_steps}") logger.info(f"embedded guidance scale: {emb_guidance_scale}") if cfg_scale != 1.0: logger.info(f"CFG scale: {cfg_scale}") # logger.info(f"sample_sampler: {sampler_name}") if seed is not None: logger.info(f"seed: {seed}") # encode prompts tokenize_strategy = strategy_base.TokenizeStrategy.get_strategy() encoding_strategy = strategy_base.TextEncodingStrategy.get_strategy() def encode_prompt(prpt): text_encoder_conds = [] if sample_prompts_te_outputs and prpt in sample_prompts_te_outputs: text_encoder_conds = sample_prompts_te_outputs[prpt] print(f"Using cached text encoder outputs for prompt: {prpt}") if text_encoders is not None: print(f"Encoding prompt: {prpt}") tokens_and_masks = tokenize_strategy.tokenize(prpt) # strategy has apply_t5_attn_mask option encoded_text_encoder_conds = encoding_strategy.encode_tokens(tokenize_strategy, text_encoders, tokens_and_masks) # if text_encoder_conds is not cached, use encoded_text_encoder_conds if len(text_encoder_conds) == 0: text_encoder_conds = encoded_text_encoder_conds else: # if encoded_text_encoder_conds is not None, update cached text_encoder_conds for i in range(len(encoded_text_encoder_conds)): if encoded_text_encoder_conds[i] is not None: text_encoder_conds[i] = encoded_text_encoder_conds[i] return text_encoder_conds l_pooled, t5_out, txt_ids, t5_attn_mask = encode_prompt(prompt) # encode negative prompts if cfg_scale != 1.0: neg_l_pooled, neg_t5_out, _, neg_t5_attn_mask = encode_prompt(negative_prompt) neg_t5_attn_mask = ( neg_t5_attn_mask.to(accelerator.device) if args.apply_t5_attn_mask and neg_t5_attn_mask is not None else None ) neg_cond = (cfg_scale, neg_l_pooled, neg_t5_out, neg_t5_attn_mask) else: neg_cond = None # sample image weight_dtype = ae.dtype # TOFO give dtype as argument packed_latent_height = height // 16 packed_latent_width = width // 16 noise = torch.randn( 1, packed_latent_height * packed_latent_width, 16 * 2 * 2, device=accelerator.device, dtype=weight_dtype, generator=torch.Generator(device=accelerator.device).manual_seed(seed) if seed is not None else None, ) timesteps = get_schedule(sample_steps, noise.shape[1], shift=True) # Chroma can use shift=True img_ids = flux_utils.prepare_img_ids(1, packed_latent_height, packed_latent_width).to(accelerator.device, weight_dtype) t5_attn_mask = t5_attn_mask.to(accelerator.device) if args.apply_t5_attn_mask else None if controlnet_image is not None: controlnet_image = Image.open(controlnet_image).convert("RGB") controlnet_image = controlnet_image.resize((width, height), Image.LANCZOS) controlnet_image = torch.from_numpy((np.array(controlnet_image) / 127.5) - 1) controlnet_image = controlnet_image.permute(2, 0, 1).unsqueeze(0).to(weight_dtype).to(accelerator.device) with accelerator.autocast(), torch.no_grad(): x = denoise( flux, noise, img_ids, t5_out, txt_ids, l_pooled, timesteps=timesteps, guidance=emb_guidance_scale, t5_attn_mask=t5_attn_mask, controlnet=controlnet, controlnet_img=controlnet_image, neg_cond=neg_cond, ) x = flux_utils.unpack_latents(x, packed_latent_height, packed_latent_width) # latent to image clean_memory_on_device(accelerator.device) org_vae_device = ae.device # will be on cpu ae.to(accelerator.device) # distributed_state.device is same as accelerator.device with accelerator.autocast(), torch.no_grad(): x = ae.decode(x) ae.to(org_vae_device) clean_memory_on_device(accelerator.device) x = x.clamp(-1, 1) x = x.permute(0, 2, 3, 1) image = Image.fromarray((127.5 * (x + 1.0)).float().cpu().numpy().astype(np.uint8)[0]) # adding accelerator.wait_for_everyone() here should sync up and ensure that sample images are saved in the same order as the original prompt list # but adding 'enum' to the filename should be enough ts_str = time.strftime("%Y%m%d%H%M%S", time.localtime()) num_suffix = f"e{epoch:06d}" if epoch is not None else f"{steps:06d}" seed_suffix = "" if seed is None else f"_{seed}" i: int = prompt_dict["enum"] img_filename = f"{'' if args.output_name is None else args.output_name + '_'}{num_suffix}_{i:02d}_{ts_str}{seed_suffix}.png" image.save(os.path.join(save_dir, img_filename)) # send images to wandb if enabled if "wandb" in [tracker.name for tracker in accelerator.trackers]: wandb_tracker = accelerator.get_tracker("wandb") import wandb # not to commit images to avoid inconsistency between training and logging steps wandb_tracker.log({f"sample_{i}": wandb.Image(image, caption=prompt)}, commit=False) # positive prompt as a caption def time_shift(mu: float, sigma: float, t: torch.Tensor): return math.exp(mu) / (math.exp(mu) + (1 / t - 1) ** sigma) def get_lin_function(x1: float = 256, y1: float = 0.5, x2: float = 4096, y2: float = 1.15) -> Callable[[float], float]: m = (y2 - y1) / (x2 - x1) b = y1 - m * x1 return lambda x: m * x + b def get_schedule( num_steps: int, image_seq_len: int, base_shift: float = 0.5, max_shift: float = 1.15, shift: bool = True, ) -> list[float]: # extra step for zero timesteps = torch.linspace(1, 0, num_steps + 1) # shifting the schedule to favor high timesteps for higher signal images if shift: # eastimate mu based on linear estimation between two points mu = get_lin_function(y1=base_shift, y2=max_shift)(image_seq_len) timesteps = time_shift(mu, 1.0, timesteps) return timesteps.tolist() def denoise( model: flux_models.Flux, img: torch.Tensor, img_ids: torch.Tensor, txt: torch.Tensor, # t5_out txt_ids: torch.Tensor, vec: torch.Tensor, # l_pooled timesteps: list[float], guidance: float = 4.0, t5_attn_mask: Optional[torch.Tensor] = None, controlnet: Optional[flux_models.ControlNetFlux] = None, controlnet_img: Optional[torch.Tensor] = None, neg_cond: Optional[Tuple[float, torch.Tensor, torch.Tensor, torch.Tensor]] = None, ): # this is ignored for schnell guidance_vec = torch.full((img.shape[0],), guidance, device=img.device, dtype=img.dtype) do_cfg = neg_cond is not None for t_curr, t_prev in zip(tqdm(timesteps[:-1]), timesteps[1:]): t_vec = torch.full((img.shape[0],), t_curr, dtype=img.dtype, device=img.device) model.prepare_block_swap_before_forward() if controlnet is not None: block_samples, block_single_samples = controlnet( img=img, img_ids=img_ids, controlnet_cond=controlnet_img, txt=txt, txt_ids=txt_ids, y=vec, timesteps=t_vec, guidance=guidance_vec, txt_attention_mask=t5_attn_mask, ) else: block_samples = None block_single_samples = None if not do_cfg: pred = model( img=img, img_ids=img_ids, txt=txt, txt_ids=txt_ids, y=vec, block_controlnet_hidden_states=block_samples, block_controlnet_single_hidden_states=block_single_samples, timesteps=t_vec, guidance=guidance_vec, txt_attention_mask=t5_attn_mask, ) img = img + (t_prev - t_curr) * pred else: cfg_scale, neg_l_pooled, neg_t5_out, neg_t5_attn_mask = neg_cond nc_c_t5_attn_mask = None if t5_attn_mask is None else torch.cat([neg_t5_attn_mask, t5_attn_mask], dim=0) # TODO is it ok to use the same block samples for both cond and uncond? block_samples = None if block_samples is None else torch.cat([block_samples, block_samples], dim=0) block_single_samples = ( None if block_single_samples is None else torch.cat([block_single_samples, block_single_samples], dim=0) ) nc_c_pred = model( img=torch.cat([img, img], dim=0), img_ids=torch.cat([img_ids, img_ids], dim=0), txt=torch.cat([neg_t5_out, txt], dim=0), txt_ids=torch.cat([txt_ids, txt_ids], dim=0), y=torch.cat([neg_l_pooled, vec], dim=0), block_controlnet_hidden_states=block_samples, block_controlnet_single_hidden_states=block_single_samples, timesteps=t_vec.repeat(2), guidance=guidance_vec.repeat(2), txt_attention_mask=nc_c_t5_attn_mask, ) neg_pred, pred = torch.chunk(nc_c_pred, 2, dim=0) pred = neg_pred + (pred - neg_pred) * cfg_scale img = img + (t_prev - t_curr) * pred model.prepare_block_swap_before_forward() return img # endregion # region train def get_sigmas(noise_scheduler, timesteps, device, n_dim=4, dtype=torch.float32): sigmas = noise_scheduler.sigmas.to(device=device, dtype=dtype) schedule_timesteps = noise_scheduler.timesteps.to(device) timesteps = timesteps.to(device) step_indices = [(schedule_timesteps == t).nonzero().item() for t in timesteps] sigma = sigmas[step_indices].flatten() return sigma def compute_density_for_timestep_sampling( weighting_scheme: str, batch_size: int, logit_mean: float = None, logit_std: float = None, mode_scale: float = None ): """Compute the density for sampling the timesteps when doing SD3 training. Courtesy: This was contributed by Rafie Walker in https://github.com/huggingface/diffusers/pull/8528. SD3 paper reference: https://arxiv.org/abs/2403.03206v1. """ if weighting_scheme == "logit_normal": # See 3.1 in the SD3 paper ($rf/lognorm(0.00,1.00)$). u = torch.normal(mean=logit_mean, std=logit_std, size=(batch_size,), device="cpu") u = torch.nn.functional.sigmoid(u) elif weighting_scheme == "mode": u = torch.rand(size=(batch_size,), device="cpu") u = 1 - u - mode_scale * (torch.cos(math.pi * u / 2) ** 2 - 1 + u) else: u = torch.rand(size=(batch_size,), device="cpu") return u def compute_loss_weighting_for_sd3(weighting_scheme: str, sigmas=None): """Computes loss weighting scheme for SD3 training. Courtesy: This was contributed by Rafie Walker in https://github.com/huggingface/diffusers/pull/8528. SD3 paper reference: https://arxiv.org/abs/2403.03206v1. """ if weighting_scheme == "sigma_sqrt": weighting = (sigmas**-2.0).float() elif weighting_scheme == "cosmap": bot = 1 - 2 * sigmas + 2 * sigmas**2 weighting = 2 / (math.pi * bot) else: weighting = torch.ones_like(sigmas) return weighting def get_noisy_model_input_and_timesteps( args, noise_scheduler, latents: torch.Tensor, noise: torch.Tensor, device, dtype ) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor]: bsz, h, w = latents.shape[0], latents.shape[-2], latents.shape[-1] assert bsz > 0, "Batch size not large enough" num_timesteps = noise_scheduler.config.num_train_timesteps if args.timestep_sampling == "uniform" or args.timestep_sampling == "sigmoid": # Simple random sigma-based noise sampling if args.timestep_sampling == "sigmoid": # https://github.com/XLabs-AI/x-flux/tree/main sigmas = torch.sigmoid(args.sigmoid_scale * torch.randn((bsz,), device=device)) else: sigmas = torch.rand((bsz,), device=device) timesteps = sigmas * num_timesteps elif args.timestep_sampling == "shift": shift = args.discrete_flow_shift sigmas = torch.randn(bsz, device=device) sigmas = sigmas * args.sigmoid_scale # larger scale for more uniform sampling sigmas = sigmas.sigmoid() sigmas = (sigmas * shift) / (1 + (shift - 1) * sigmas) timesteps = sigmas * num_timesteps elif args.timestep_sampling == "flux_shift": sigmas = torch.randn(bsz, device=device) sigmas = sigmas * args.sigmoid_scale # larger scale for more uniform sampling sigmas = sigmas.sigmoid() mu = get_lin_function(y1=0.5, y2=1.15)((h // 2) * (w // 2)) # we are pre-packed so must adjust for packed size sigmas = time_shift(mu, 1.0, sigmas) timesteps = sigmas * num_timesteps else: # Sample a random timestep for each image # for weighting schemes where we sample timesteps non-uniformly u = compute_density_for_timestep_sampling( weighting_scheme=args.weighting_scheme, batch_size=bsz, logit_mean=args.logit_mean, logit_std=args.logit_std, mode_scale=args.mode_scale, ) indices = (u * num_timesteps).long() timesteps = noise_scheduler.timesteps[indices].to(device=device) sigmas = get_sigmas(noise_scheduler, timesteps, device, n_dim=latents.ndim, dtype=dtype) # Broadcast sigmas to latent shape sigmas = sigmas.view(-1, 1, 1, 1) if latents.ndim == 4 else sigmas.view(-1, 1, 1, 1, 1) # Add noise to the latents according to the noise magnitude at each timestep # (this is the forward diffusion process) if args.ip_noise_gamma: xi = torch.randn_like(latents, device=latents.device, dtype=dtype) if args.ip_noise_gamma_random_strength: ip_noise_gamma = torch.rand(1, device=latents.device, dtype=dtype) * args.ip_noise_gamma else: ip_noise_gamma = args.ip_noise_gamma noisy_model_input = (1.0 - sigmas) * latents + sigmas * (noise + ip_noise_gamma * xi) else: noisy_model_input = (1.0 - sigmas) * latents + sigmas * noise return noisy_model_input.to(dtype), timesteps.to(dtype), sigmas def apply_model_prediction_type(args, model_pred, noisy_model_input, sigmas): weighting = None if args.model_prediction_type == "raw": pass elif args.model_prediction_type == "additive": # add the model_pred to the noisy_model_input model_pred = model_pred + noisy_model_input elif args.model_prediction_type == "sigma_scaled": # apply sigma scaling model_pred = model_pred * (-sigmas) + noisy_model_input # these weighting schemes use a uniform timestep sampling # and instead post-weight the loss weighting = compute_loss_weighting_for_sd3(weighting_scheme=args.weighting_scheme, sigmas=sigmas) return model_pred, weighting def save_models( ckpt_path: str, flux: flux_models.Flux, sai_metadata: Optional[dict], save_dtype: Optional[torch.dtype] = None, use_mem_eff_save: bool = False, ): state_dict = {} def update_sd(prefix, sd): for k, v in sd.items(): key = prefix + k if save_dtype is not None and v.dtype != save_dtype: v = v.detach().clone().to("cpu").to(save_dtype) state_dict[key] = v update_sd("", flux.state_dict()) if not use_mem_eff_save: save_file(state_dict, ckpt_path, metadata=sai_metadata) else: mem_eff_save_file(state_dict, ckpt_path, metadata=sai_metadata) def save_flux_model_on_train_end( args: argparse.Namespace, save_dtype: torch.dtype, epoch: int, global_step: int, flux: flux_models.Flux ): def sd_saver(ckpt_file, epoch_no, global_step): sai_metadata = train_util.get_sai_model_spec(None, args, False, False, False, is_stable_diffusion_ckpt=True, flux="dev") save_models(ckpt_file, flux, sai_metadata, save_dtype, args.mem_eff_save) train_util.save_sd_model_on_train_end_common(args, True, True, epoch, global_step, sd_saver, None) # epochとstepの保存、メタデータにepoch/stepが含まれ引数が同じになるため、統合している # on_epoch_end: Trueならepoch終了時、Falseならstep経過時 def save_flux_model_on_epoch_end_or_stepwise( args: argparse.Namespace, on_epoch_end: bool, accelerator, save_dtype: torch.dtype, epoch: int, num_train_epochs: int, global_step: int, flux: flux_models.Flux, ): def sd_saver(ckpt_file, epoch_no, global_step): sai_metadata = train_util.get_sai_model_spec(None, args, False, False, False, is_stable_diffusion_ckpt=True, flux="dev") save_models(ckpt_file, flux, sai_metadata, save_dtype, args.mem_eff_save) train_util.save_sd_model_on_epoch_end_or_stepwise_common( args, on_epoch_end, accelerator, True, True, epoch, num_train_epochs, global_step, sd_saver, None, ) # endregion def add_flux_train_arguments(parser: argparse.ArgumentParser): parser.add_argument( "--clip_l", type=str, help="path to clip_l (*.sft or *.safetensors), should be float16 / clip_lのパス（*.sftまたは*.safetensors）、float16が前提", ) parser.add_argument( "--t5xxl", type=str, help="path to t5xxl (*.sft or *.safetensors), should be float16 / t5xxlのパス（*.sftまたは*.safetensors）、float16が前提", ) parser.add_argument("--ae", type=str, help="path to ae (*.sft or *.safetensors) / aeのパス（*.sftまたは*.safetensors）") parser.add_argument( "--controlnet_model_name_or_path", type=str, default=None, help="path to controlnet (*.sft or *.safetensors) / controlnetのパス（*.sftまたは*.safetensors）", ) parser.add_argument( "--t5xxl_max_token_length", type=int, default=None, help="maximum token length for T5-XXL. if omitted, 256 for schnell and 512 for dev" " / T5-XXLの最大トークン長。省略された場合、schnellの場合は256、devの場合は512", ) parser.add_argument( "--apply_t5_attn_mask", action="store_true", help="apply attention mask to T5-XXL encode and FLUX double blocks / T5-XXLエンコードとFLUXダブルブロックにアテンションマスクを適用する", ) parser.add_argument( "--guidance_scale", type=float, default=3.5, help="the FLUX.1 dev variant is a guidance distilled model", ) parser.add_argument( "--timestep_sampling", choices=["sigma", "uniform", "sigmoid", "shift", "flux_shift"], default="sigma", help="Method to sample timesteps: sigma-based, uniform random, sigmoid of random normal, shift of sigmoid and FLUX.1 shifting." " / タイムステップをサンプリングする方法：sigma、random uniform、random normalのsigmoid、sigmoidのシフト、FLUX.1のシフト。", ) parser.add_argument( "--sigmoid_scale", type=float, default=1.0, help='Scale factor for sigmoid timestep sampling (only used when timestep-sampling is "sigmoid"). / sigmoidタイムステップサンプリングの倍率（timestep-samplingが"sigmoid"の場合のみ有効）。', ) parser.add_argument( "--model_prediction_type", choices=["raw", "additive", "sigma_scaled"], default="sigma_scaled", help="How to interpret and process the model prediction: " "raw (use as is), additive (add to noisy input), sigma_scaled (apply sigma scaling)." " / モデル予測の解釈と処理方法：" "raw（そのまま使用）、additive（ノイズ入力に加算）、sigma_scaled（シグマスケーリングを適用）。", ) parser.add_argument( "--discrete_flow_shift", type=float, default=3.0, help="Discrete flow shift for the Euler Discrete Scheduler, default is 3.0. / Euler Discrete Schedulerの離散フローシフト、デフォルトは3.0。", ) parser.add_argument( "--model_type", type=str, choices=["flux", "chroma"], default="flux", help="Model type to use for training / トレーニングに使用するモデルタイプ：flux or chroma (default: flux)", )