#!/usr/bin/env python # coding=utf-8 # Copyright 2023 The HuggingFace Inc. team. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. """Fine-tuning script for Stable Diffusion XL for text2image with support for LoRA.""" import argparse import itertools import logging import math import os import random import shutil from pathlib import Path from typing import Dict import datasets import numpy as np import torch import torch.nn.functional as F import torch.utils.checkpoint import transformers from accelerate import Accelerator from accelerate.logging import get_logger from accelerate.utils import DistributedDataParallelKwargs, ProjectConfiguration, set_seed from datasets import load_dataset from huggingface_hub import create_repo, upload_folder from packaging import version from torchvision import transforms from torchvision.transforms.functional import crop from tqdm.auto import tqdm from transformers import AutoTokenizer, PretrainedConfig import diffusers from diffusers import ( AutoencoderKL, DDPMScheduler, StableDiffusionXLPipeline, UNet2DConditionModel, ) from diffusers.loaders import LoraLoaderMixin, text_encoder_lora_state_dict from diffusers.models.lora import LoRALinearLayer from diffusers.optimization import get_scheduler from diffusers.training_utils import compute_snr from diffusers.utils import check_min_version, is_wandb_available from diffusers.utils.import_utils import is_xformers_available # Will error if the minimal version of diffusers is not installed. Remove at your own risks. check_min_version("0.22.0.dev0") logger = get_logger(__name__) def save_model_card( repo_id: str, images=None, base_model=str, dataset_name=str, train_text_encoder=False, repo_folder=None, vae_path=None, ): img_str = "" for i, image in enumerate(images): image.save(os.path.join(repo_folder, f"image_{i}.png")) img_str += f"![img_{i}](./image_{i}.png)\n" yaml = f""" --- license: creativeml-openrail-m base_model: {base_model} dataset: {dataset_name} tags: - stable-diffusion-xl - stable-diffusion-xl-diffusers - text-to-image - diffusers - lora inference: true --- """ model_card = f""" # LoRA text2image fine-tuning - {repo_id} These are LoRA adaption weights for {base_model}. The weights were fine-tuned on the {dataset_name} dataset. You can find some example images in the following. \n {img_str} LoRA for the text encoder was enabled: {train_text_encoder}. Special VAE used for training: {vae_path}. """ with open(os.path.join(repo_folder, "README.md"), "w") as f: f.write(yaml + model_card) def import_model_class_from_model_name_or_path( pretrained_model_name_or_path: str, revision: str, subfolder: str = "text_encoder" ): text_encoder_config = PretrainedConfig.from_pretrained( pretrained_model_name_or_path, subfolder=subfolder, revision=revision ) model_class = text_encoder_config.architectures[0] if model_class == "CLIPTextModel": from transformers import CLIPTextModel return CLIPTextModel elif model_class == "CLIPTextModelWithProjection": from transformers import CLIPTextModelWithProjection return CLIPTextModelWithProjection else: raise ValueError(f"{model_class} is not supported.") def parse_args(input_args=None): parser = argparse.ArgumentParser(description="Simple example of a training script.") parser.add_argument( "--pretrained_model_name_or_path", type=str, default=None, required=True, help="Path to pretrained model or model identifier from huggingface.co/models.", ) parser.add_argument( "--pretrained_vae_model_name_or_path", type=str, default=None, help="Path to pretrained VAE model with better numerical stability. More details: https://github.com/huggingface/diffusers/pull/4038.", ) parser.add_argument( "--revision", type=str, default=None, required=False, help="Revision of pretrained model identifier from huggingface.co/models.", ) parser.add_argument( "--dataset_name", type=str, default=None, help=( "The name of the Dataset (from the HuggingFace hub) to train on (could be your own, possibly private," " dataset). It can also be a path pointing to a local copy of a dataset in your filesystem," " or to a folder containing files that 🤗 Datasets can understand." ), ) parser.add_argument( "--dataset_config_name", type=str, default=None, help="The config of the Dataset, leave as None if there's only one config.", ) parser.add_argument( "--train_data_dir", type=str, default=None, help=( "A folder containing the training data. Folder contents must follow the structure described in" " https://huggingface.co/docs/datasets/image_dataset#imagefolder. In particular, a `metadata.jsonl` file" " must exist to provide the captions for the images. Ignored if `dataset_name` is specified." ), ) parser.add_argument( "--image_column", type=str, default="image", help="The column of the dataset containing an image." ) parser.add_argument( "--caption_column", type=str, default="text", help="The column of the dataset containing a caption or a list of captions.", ) parser.add_argument( "--validation_prompt", type=str, default=None, help="A prompt that is used during validation to verify that the model is learning.", ) parser.add_argument( "--num_validation_images", type=int, default=4, help="Number of images that should be generated during validation with `validation_prompt`.", ) parser.add_argument( "--validation_epochs", type=int, default=1, help=( "Run fine-tuning validation every X epochs. The validation process consists of running the prompt" " `args.validation_prompt` multiple times: `args.num_validation_images`." ), ) parser.add_argument( "--max_train_samples", type=int, default=None, help=( "For debugging purposes or quicker training, truncate the number of training examples to this " "value if set." ), ) parser.add_argument( "--output_dir", type=str, default="sd-model-finetuned-lora", help="The output directory where the model predictions and checkpoints will be written.", ) parser.add_argument( "--cache_dir", type=str, default=None, help="The directory where the downloaded models and datasets will be stored.", ) parser.add_argument("--seed", type=int, default=None, help="A seed for reproducible training.") parser.add_argument( "--resolution", type=int, default=1024, help=( "The resolution for input images, all the images in the train/validation dataset will be resized to this" " resolution" ), ) parser.add_argument( "--center_crop", default=False, action="store_true", help=( "Whether to center crop the input images to the resolution. If not set, the images will be randomly" " cropped. The images will be resized to the resolution first before cropping." ), ) parser.add_argument( "--random_flip", action="store_true", help="whether to randomly flip images horizontally", ) parser.add_argument( "--train_text_encoder", action="store_true", help="Whether to train the text encoder. If set, the text encoder should be float32 precision.", ) parser.add_argument( "--train_batch_size", type=int, default=16, help="Batch size (per device) for the training dataloader." ) parser.add_argument("--num_train_epochs", type=int, default=100) parser.add_argument( "--max_train_steps", type=int, default=None, help="Total number of training steps to perform. If provided, overrides num_train_epochs.", ) parser.add_argument( "--checkpointing_steps", type=int, default=500, help=( "Save a checkpoint of the training state every X updates. These checkpoints can be used both as final" " checkpoints in case they are better than the last checkpoint, and are also suitable for resuming" " training using `--resume_from_checkpoint`." ), ) parser.add_argument( "--checkpoints_total_limit", type=int, default=None, help=("Max number of checkpoints to store."), ) parser.add_argument( "--resume_from_checkpoint", type=str, default=None, help=( "Whether training should be resumed from a previous checkpoint. Use a path saved by" ' `--checkpointing_steps`, or `"latest"` to automatically select the last available checkpoint.' ), ) parser.add_argument( "--gradient_accumulation_steps", type=int, default=1, help="Number of updates steps to accumulate before performing a backward/update pass.", ) parser.add_argument( "--gradient_checkpointing", action="store_true", help="Whether or not to use gradient checkpointing to save memory at the expense of slower backward pass.", ) parser.add_argument( "--learning_rate", type=float, default=1e-4, help="Initial learning rate (after the potential warmup period) to use.", ) parser.add_argument( "--scale_lr", action="store_true", default=False, help="Scale the learning rate by the number of GPUs, gradient accumulation steps, and batch size.", ) parser.add_argument( "--lr_scheduler", type=str, default="constant", help=( 'The scheduler type to use. Choose between ["linear", "cosine", "cosine_with_restarts", "polynomial",' ' "constant", "constant_with_warmup"]' ), ) parser.add_argument( "--lr_warmup_steps", type=int, default=500, help="Number of steps for the warmup in the lr scheduler." ) parser.add_argument( "--snr_gamma", type=float, default=None, help="SNR weighting gamma to be used if rebalancing the loss. Recommended value is 5.0. " "More details here: https://arxiv.org/abs/2303.09556.", ) parser.add_argument( "--allow_tf32", action="store_true", help=( "Whether or not to allow TF32 on Ampere GPUs. Can be used to speed up training. For more information, see" " https://pytorch.org/docs/stable/notes/cuda.html#tensorfloat-32-tf32-on-ampere-devices" ), ) parser.add_argument( "--dataloader_num_workers", type=int, default=0, help=( "Number of subprocesses to use for data loading. 0 means that the data will be loaded in the main process." ), ) parser.add_argument( "--use_8bit_adam", action="store_true", help="Whether or not to use 8-bit Adam from bitsandbytes." ) parser.add_argument("--adam_beta1", type=float, default=0.9, help="The beta1 parameter for the Adam optimizer.") parser.add_argument("--adam_beta2", type=float, default=0.999, help="The beta2 parameter for the Adam optimizer.") parser.add_argument("--adam_weight_decay", type=float, default=1e-2, help="Weight decay to use.") parser.add_argument("--adam_epsilon", type=float, default=1e-08, help="Epsilon value for the Adam optimizer") parser.add_argument("--max_grad_norm", default=1.0, type=float, help="Max gradient norm.") parser.add_argument("--push_to_hub", action="store_true", help="Whether or not to push the model to the Hub.") parser.add_argument("--hub_token", type=str, default=None, help="The token to use to push to the Model Hub.") parser.add_argument( "--prediction_type", type=str, default=None, help="The prediction_type that shall be used for training. Choose between 'epsilon' or 'v_prediction' or leave `None`. If left to `None` the default prediction type of the scheduler: `noise_scheduler.config.prediciton_type` is chosen.", ) parser.add_argument( "--hub_model_id", type=str, default=None, help="The name of the repository to keep in sync with the local `output_dir`.", ) parser.add_argument( "--logging_dir", type=str, default="logs", help=( "[TensorBoard](https://www.tensorflow.org/tensorboard) log directory. Will default to" " *output_dir/runs/**CURRENT_DATETIME_HOSTNAME***." ), ) parser.add_argument( "--report_to", type=str, default="tensorboard", help=( 'The integration to report the results and logs to. Supported platforms are `"tensorboard"`' ' (default), `"wandb"` and `"comet_ml"`. Use `"all"` to report to all integrations.' ), ) parser.add_argument( "--mixed_precision", type=str, default=None, choices=["no", "fp16", "bf16"], help=( "Whether to use mixed precision. Choose between fp16 and bf16 (bfloat16). Bf16 requires PyTorch >=" " 1.10.and an Nvidia Ampere GPU. Default to the value of accelerate config of the current system or the" " flag passed with the `accelerate.launch` command. Use this argument to override the accelerate config." ), ) parser.add_argument("--local_rank", type=int, default=-1, help="For distributed training: local_rank") parser.add_argument( "--enable_xformers_memory_efficient_attention", action="store_true", help="Whether or not to use xformers." ) parser.add_argument("--noise_offset", type=float, default=0, help="The scale of noise offset.") parser.add_argument( "--rank", type=int, default=4, help=("The dimension of the LoRA update matrices."), ) if input_args is not None: args = parser.parse_args(input_args) else: args = parser.parse_args() env_local_rank = int(os.environ.get("LOCAL_RANK", -1)) if env_local_rank != -1 and env_local_rank != args.local_rank: args.local_rank = env_local_rank # Sanity checks if args.dataset_name is None and args.train_data_dir is None: raise ValueError("Need either a dataset name or a training folder.") return args DATASET_NAME_MAPPING = { "lambdalabs/pokemon-blip-captions": ("image", "text"), } def unet_attn_processors_state_dict(unet) -> Dict[str, torch.tensor]: """ Returns: a state dict containing just the attention processor parameters. """ attn_processors = unet.attn_processors attn_processors_state_dict = {} for attn_processor_key, attn_processor in attn_processors.items(): for parameter_key, parameter in attn_processor.state_dict().items(): attn_processors_state_dict[f"{attn_processor_key}.{parameter_key}"] = parameter return attn_processors_state_dict def tokenize_prompt(tokenizer, prompt): text_inputs = tokenizer( prompt, padding="max_length", max_length=tokenizer.model_max_length, truncation=True, return_tensors="pt", ) text_input_ids = text_inputs.input_ids return text_input_ids # Adapted from pipelines.StableDiffusionXLPipeline.encode_prompt def encode_prompt(text_encoders, tokenizers, prompt, text_input_ids_list=None): prompt_embeds_list = [] for i, text_encoder in enumerate(text_encoders): if tokenizers is not None: tokenizer = tokenizers[i] text_input_ids = tokenize_prompt(tokenizer, prompt) else: assert text_input_ids_list is not None text_input_ids = text_input_ids_list[i] prompt_embeds = text_encoder( text_input_ids.to(text_encoder.device), output_hidden_states=True, ) # We are only ALWAYS interested in the pooled output of the final text encoder pooled_prompt_embeds = prompt_embeds[0] prompt_embeds = prompt_embeds.hidden_states[-2] bs_embed, seq_len, _ = prompt_embeds.shape prompt_embeds = prompt_embeds.view(bs_embed, seq_len, -1) prompt_embeds_list.append(prompt_embeds) prompt_embeds = torch.concat(prompt_embeds_list, dim=-1) pooled_prompt_embeds = pooled_prompt_embeds.view(bs_embed, -1) return prompt_embeds, pooled_prompt_embeds def main(args): logging_dir = Path(args.output_dir, args.logging_dir) accelerator_project_config = ProjectConfiguration(project_dir=args.output_dir, logging_dir=logging_dir) kwargs = DistributedDataParallelKwargs(find_unused_parameters=True) accelerator = Accelerator( gradient_accumulation_steps=args.gradient_accumulation_steps, mixed_precision=args.mixed_precision, log_with=args.report_to, project_config=accelerator_project_config, kwargs_handlers=[kwargs], ) if args.report_to == "wandb": if not is_wandb_available(): raise ImportError("Make sure to install wandb if you want to use it for logging during training.") import wandb # Make one log on every process with the configuration for debugging. logging.basicConfig( format="%(asctime)s - %(levelname)s - %(name)s - %(message)s", datefmt="%m/%d/%Y %H:%M:%S", level=logging.INFO, ) logger.info(accelerator.state, main_process_only=False) if accelerator.is_local_main_process: datasets.utils.logging.set_verbosity_warning() transformers.utils.logging.set_verbosity_warning() diffusers.utils.logging.set_verbosity_info() else: datasets.utils.logging.set_verbosity_error() transformers.utils.logging.set_verbosity_error() diffusers.utils.logging.set_verbosity_error() # If passed along, set the training seed now. if args.seed is not None: set_seed(args.seed) # Handle the repository creation if accelerator.is_main_process: if args.output_dir is not None: os.makedirs(args.output_dir, exist_ok=True) if args.push_to_hub: repo_id = create_repo( repo_id=args.hub_model_id or Path(args.output_dir).name, exist_ok=True, token=args.hub_token ).repo_id # Load the tokenizers tokenizer_one = AutoTokenizer.from_pretrained( args.pretrained_model_name_or_path, subfolder="tokenizer", revision=args.revision, use_fast=False ) tokenizer_two = AutoTokenizer.from_pretrained( args.pretrained_model_name_or_path, subfolder="tokenizer_2", revision=args.revision, use_fast=False ) # import correct text encoder classes text_encoder_cls_one = import_model_class_from_model_name_or_path( args.pretrained_model_name_or_path, args.revision ) text_encoder_cls_two = import_model_class_from_model_name_or_path( args.pretrained_model_name_or_path, args.revision, subfolder="text_encoder_2" ) # Load scheduler and models noise_scheduler = DDPMScheduler.from_pretrained(args.pretrained_model_name_or_path, subfolder="scheduler") text_encoder_one = text_encoder_cls_one.from_pretrained( args.pretrained_model_name_or_path, subfolder="text_encoder", revision=args.revision ) text_encoder_two = text_encoder_cls_two.from_pretrained( args.pretrained_model_name_or_path, subfolder="text_encoder_2", revision=args.revision ) vae_path = ( args.pretrained_model_name_or_path if args.pretrained_vae_model_name_or_path is None else args.pretrained_vae_model_name_or_path ) vae = AutoencoderKL.from_pretrained( vae_path, subfolder="vae" if args.pretrained_vae_model_name_or_path is None else None, revision=args.revision ) unet = UNet2DConditionModel.from_pretrained( args.pretrained_model_name_or_path, subfolder="unet", revision=args.revision ) # We only train the additional adapter LoRA layers vae.requires_grad_(False) text_encoder_one.requires_grad_(False) text_encoder_two.requires_grad_(False) unet.requires_grad_(False) # For mixed precision training we cast all non-trainable weigths (vae, non-lora text_encoder and non-lora unet) to half-precision # as these weights are only used for inference, keeping weights in full precision is not required. weight_dtype = torch.float32 if accelerator.mixed_precision == "fp16": weight_dtype = torch.float16 elif accelerator.mixed_precision == "bf16": weight_dtype = torch.bfloat16 # Move unet, vae and text_encoder to device and cast to weight_dtype # The VAE is in float32 to avoid NaN losses. unet.to(accelerator.device, dtype=weight_dtype) if args.pretrained_vae_model_name_or_path is None: vae.to(accelerator.device, dtype=torch.float32) else: vae.to(accelerator.device, dtype=weight_dtype) text_encoder_one.to(accelerator.device, dtype=weight_dtype) text_encoder_two.to(accelerator.device, dtype=weight_dtype) if args.enable_xformers_memory_efficient_attention: if is_xformers_available(): import xformers xformers_version = version.parse(xformers.__version__) if xformers_version == version.parse("0.0.16"): logger.warn( "xFormers 0.0.16 cannot be used for training in some GPUs. If you observe problems during training, please update xFormers to at least 0.0.17. See https://huggingface.co/docs/diffusers/main/en/optimization/xformers for more details." ) unet.enable_xformers_memory_efficient_attention() else: raise ValueError("xformers is not available. Make sure it is installed correctly") # now we will add new LoRA weights to the attention layers # Set correct lora layers unet_lora_parameters = [] for attn_processor_name, attn_processor in unet.attn_processors.items(): # Parse the attention module. attn_module = unet for n in attn_processor_name.split(".")[:-1]: attn_module = getattr(attn_module, n) # Set the `lora_layer` attribute of the attention-related matrices. attn_module.to_q.set_lora_layer( LoRALinearLayer( in_features=attn_module.to_q.in_features, out_features=attn_module.to_q.out_features, rank=args.rank ) ) attn_module.to_k.set_lora_layer( LoRALinearLayer( in_features=attn_module.to_k.in_features, out_features=attn_module.to_k.out_features, rank=args.rank ) ) attn_module.to_v.set_lora_layer( LoRALinearLayer( in_features=attn_module.to_v.in_features, out_features=attn_module.to_v.out_features, rank=args.rank ) ) attn_module.to_out[0].set_lora_layer( LoRALinearLayer( in_features=attn_module.to_out[0].in_features, out_features=attn_module.to_out[0].out_features, rank=args.rank, ) ) # Accumulate the LoRA params to optimize. unet_lora_parameters.extend(attn_module.to_q.lora_layer.parameters()) unet_lora_parameters.extend(attn_module.to_k.lora_layer.parameters()) unet_lora_parameters.extend(attn_module.to_v.lora_layer.parameters()) unet_lora_parameters.extend(attn_module.to_out[0].lora_layer.parameters()) # The text encoder comes from 🤗 transformers, so we cannot directly modify it. # So, instead, we monkey-patch the forward calls of its attention-blocks. if args.train_text_encoder: # ensure that dtype is float32, even if rest of the model that isn't trained is loaded in fp16 text_lora_parameters_one = LoraLoaderMixin._modify_text_encoder( text_encoder_one, dtype=torch.float32, rank=args.rank ) text_lora_parameters_two = LoraLoaderMixin._modify_text_encoder( text_encoder_two, dtype=torch.float32, rank=args.rank ) # create custom saving & loading hooks so that `accelerator.save_state(...)` serializes in a nice format def save_model_hook(models, weights, output_dir): if accelerator.is_main_process: # there are only two options here. Either are just the unet attn processor layers # or there are the unet and text encoder atten layers unet_lora_layers_to_save = None text_encoder_one_lora_layers_to_save = None text_encoder_two_lora_layers_to_save = None for model in models: if isinstance(model, type(accelerator.unwrap_model(unet))): unet_lora_layers_to_save = unet_attn_processors_state_dict(model) elif isinstance(model, type(accelerator.unwrap_model(text_encoder_one))): text_encoder_one_lora_layers_to_save = text_encoder_lora_state_dict(model) elif isinstance(model, type(accelerator.unwrap_model(text_encoder_two))): text_encoder_two_lora_layers_to_save = text_encoder_lora_state_dict(model) else: raise ValueError(f"unexpected save model: {model.__class__}") # make sure to pop weight so that corresponding model is not saved again weights.pop() StableDiffusionXLPipeline.save_lora_weights( output_dir, unet_lora_layers=unet_lora_layers_to_save, text_encoder_lora_layers=text_encoder_one_lora_layers_to_save, text_encoder_2_lora_layers=text_encoder_two_lora_layers_to_save, ) def load_model_hook(models, input_dir): unet_ = None text_encoder_one_ = None text_encoder_two_ = None while len(models) > 0: model = models.pop() if isinstance(model, type(accelerator.unwrap_model(unet))): unet_ = model elif isinstance(model, type(accelerator.unwrap_model(text_encoder_one))): text_encoder_one_ = model elif isinstance(model, type(accelerator.unwrap_model(text_encoder_two))): text_encoder_two_ = model else: raise ValueError(f"unexpected save model: {model.__class__}") lora_state_dict, network_alphas = LoraLoaderMixin.lora_state_dict(input_dir) LoraLoaderMixin.load_lora_into_unet(lora_state_dict, network_alphas=network_alphas, unet=unet_) text_encoder_state_dict = {k: v for k, v in lora_state_dict.items() if "text_encoder." in k} LoraLoaderMixin.load_lora_into_text_encoder( text_encoder_state_dict, network_alphas=network_alphas, text_encoder=text_encoder_one_ ) text_encoder_2_state_dict = {k: v for k, v in lora_state_dict.items() if "text_encoder_2." in k} LoraLoaderMixin.load_lora_into_text_encoder( text_encoder_2_state_dict, network_alphas=network_alphas, text_encoder=text_encoder_two_ ) accelerator.register_save_state_pre_hook(save_model_hook) accelerator.register_load_state_pre_hook(load_model_hook) # Enable TF32 for faster training on Ampere GPUs, # cf https://pytorch.org/docs/stable/notes/cuda.html#tensorfloat-32-tf32-on-ampere-devices if args.allow_tf32: torch.backends.cuda.matmul.allow_tf32 = True if args.scale_lr: args.learning_rate = ( args.learning_rate * args.gradient_accumulation_steps * args.train_batch_size * accelerator.num_processes ) # Use 8-bit Adam for lower memory usage or to fine-tune the model in 16GB GPUs if args.use_8bit_adam: try: import bitsandbytes as bnb except ImportError: raise ImportError( "To use 8-bit Adam, please install the bitsandbytes library: `pip install bitsandbytes`." ) optimizer_class = bnb.optim.AdamW8bit else: optimizer_class = torch.optim.AdamW # Optimizer creation params_to_optimize = ( itertools.chain(unet_lora_parameters, text_lora_parameters_one, text_lora_parameters_two) if args.train_text_encoder else unet_lora_parameters ) optimizer = optimizer_class( params_to_optimize, lr=args.learning_rate, betas=(args.adam_beta1, args.adam_beta2), weight_decay=args.adam_weight_decay, eps=args.adam_epsilon, ) # Get the datasets: you can either provide your own training and evaluation files (see below) # or specify a Dataset from the hub (the dataset will be downloaded automatically from the datasets Hub). # In distributed training, the load_dataset function guarantees that only one local process can concurrently # download the dataset. if args.dataset_name is not None: # Downloading and loading a dataset from the hub. dataset = load_dataset( args.dataset_name, args.dataset_config_name, cache_dir=args.cache_dir, ) else: data_files = {} if args.train_data_dir is not None: data_files["train"] = os.path.join(args.train_data_dir, "**") dataset = load_dataset( "imagefolder", data_files=data_files, cache_dir=args.cache_dir, ) # See more about loading custom images at # https://huggingface.co/docs/datasets/v2.4.0/en/image_load#imagefolder # Preprocessing the datasets. # We need to tokenize inputs and targets. column_names = dataset["train"].column_names # 6. Get the column names for input/target. dataset_columns = DATASET_NAME_MAPPING.get(args.dataset_name, None) if args.image_column is None: image_column = dataset_columns[0] if dataset_columns is not None else column_names[0] else: image_column = args.image_column if image_column not in column_names: raise ValueError( f"--image_column' value '{args.image_column}' needs to be one of: {', '.join(column_names)}" ) if args.caption_column is None: caption_column = dataset_columns[1] if dataset_columns is not None else column_names[1] else: caption_column = args.caption_column if caption_column not in column_names: raise ValueError( f"--caption_column' value '{args.caption_column}' needs to be one of: {', '.join(column_names)}" ) # Preprocessing the datasets. # We need to tokenize input captions and transform the images. def tokenize_captions(examples, is_train=True): captions = [] for caption in examples[caption_column]: if isinstance(caption, str): captions.append(caption) elif isinstance(caption, (list, np.ndarray)): # take a random caption if there are multiple captions.append(random.choice(caption) if is_train else caption[0]) else: raise ValueError( f"Caption column `{caption_column}` should contain either strings or lists of strings." ) tokens_one = tokenize_prompt(tokenizer_one, captions) tokens_two = tokenize_prompt(tokenizer_two, captions) return tokens_one, tokens_two # Preprocessing the datasets. train_resize = transforms.Resize(args.resolution, interpolation=transforms.InterpolationMode.BILINEAR) train_crop = transforms.CenterCrop(args.resolution) if args.center_crop else transforms.RandomCrop(args.resolution) train_flip = transforms.RandomHorizontalFlip(p=1.0) train_transforms = transforms.Compose( [ transforms.ToTensor(), transforms.Normalize([0.5], [0.5]), ] ) def preprocess_train(examples): images = [image.convert("RGB") for image in examples[image_column]] # image aug original_sizes = [] all_images = [] crop_top_lefts = [] for image in images: original_sizes.append((image.width, image.height)) image = train_resize(image) if args.center_crop: y1 = max(0, int(round((image.height - args.resolution) / 2.0))) x1 = max(0, int(round((image.width - args.resolution) / 2.0))) image = train_crop(image) else: y1, x1, h, w = train_crop.get_params(image, (args.resolution, args.resolution)) image = crop(image, y1, x1, h, w) if args.random_flip and random.random() < 0.5: # flip x1 = image.width - x1 image = train_flip(image) crop_top_left = (y1, x1) crop_top_lefts.append(crop_top_left) image = train_transforms(image) all_images.append(image) examples["original_sizes"] = original_sizes examples["crop_top_lefts"] = crop_top_lefts examples["pixel_values"] = all_images tokens_one, tokens_two = tokenize_captions(examples) examples["input_ids_one"] = tokens_one examples["input_ids_two"] = tokens_two return examples with accelerator.main_process_first(): if args.max_train_samples is not None: dataset["train"] = dataset["train"].shuffle(seed=args.seed).select(range(args.max_train_samples)) # Set the training transforms train_dataset = dataset["train"].with_transform(preprocess_train) def collate_fn(examples): pixel_values = torch.stack([example["pixel_values"] for example in examples]) pixel_values = pixel_values.to(memory_format=torch.contiguous_format).float() original_sizes = [example["original_sizes"] for example in examples] crop_top_lefts = [example["crop_top_lefts"] for example in examples] input_ids_one = torch.stack([example["input_ids_one"] for example in examples]) input_ids_two = torch.stack([example["input_ids_two"] for example in examples]) return { "pixel_values": pixel_values, "input_ids_one": input_ids_one, "input_ids_two": input_ids_two, "original_sizes": original_sizes, "crop_top_lefts": crop_top_lefts, } # DataLoaders creation: train_dataloader = torch.utils.data.DataLoader( train_dataset, shuffle=True, collate_fn=collate_fn, batch_size=args.train_batch_size, num_workers=args.dataloader_num_workers, ) # Scheduler and math around the number of training steps. overrode_max_train_steps = False num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) if args.max_train_steps is None: args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch overrode_max_train_steps = True lr_scheduler = get_scheduler( args.lr_scheduler, optimizer=optimizer, num_warmup_steps=args.lr_warmup_steps * args.gradient_accumulation_steps, num_training_steps=args.max_train_steps * args.gradient_accumulation_steps, ) # Prepare everything with our `accelerator`. if args.train_text_encoder: unet, text_encoder_one, text_encoder_two, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( unet, text_encoder_one, text_encoder_two, optimizer, train_dataloader, lr_scheduler ) else: unet, optimizer, train_dataloader, lr_scheduler = accelerator.prepare( unet, optimizer, train_dataloader, lr_scheduler ) # We need to recalculate our total training steps as the size of the training dataloader may have changed. num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps) if overrode_max_train_steps: args.max_train_steps = args.num_train_epochs * num_update_steps_per_epoch # Afterwards we recalculate our number of training epochs args.num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch) # We need to initialize the trackers we use, and also store our configuration. # The trackers initializes automatically on the main process. if accelerator.is_main_process: accelerator.init_trackers("text2image-fine-tune", config=vars(args)) # Train! total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps logger.info("***** Running training *****") logger.info(f" Num examples = {len(train_dataset)}") logger.info(f" Num Epochs = {args.num_train_epochs}") logger.info(f" Instantaneous batch size per device = {args.train_batch_size}") logger.info(f" Total train batch size (w. parallel, distributed & accumulation) = {total_batch_size}") logger.info(f" Gradient Accumulation steps = {args.gradient_accumulation_steps}") logger.info(f" Total optimization steps = {args.max_train_steps}") global_step = 0 first_epoch = 0 # Potentially load in the weights and states from a previous save if args.resume_from_checkpoint: if args.resume_from_checkpoint != "latest": path = os.path.basename(args.resume_from_checkpoint) else: # Get the most recent checkpoint dirs = os.listdir(args.output_dir) dirs = [d for d in dirs if d.startswith("checkpoint")] dirs = sorted(dirs, key=lambda x: int(x.split("-")[1])) path = dirs[-1] if len(dirs) > 0 else None if path is None: accelerator.print( f"Checkpoint '{args.resume_from_checkpoint}' does not exist. Starting a new training run." ) args.resume_from_checkpoint = None initial_global_step = 0 else: accelerator.print(f"Resuming from checkpoint {path}") accelerator.load_state(os.path.join(args.output_dir, path)) global_step = int(path.split("-")[1]) initial_global_step = global_step first_epoch = global_step // num_update_steps_per_epoch else: initial_global_step = 0 progress_bar = tqdm( range(0, args.max_train_steps), initial=initial_global_step, desc="Steps", # Only show the progress bar once on each machine. disable=not accelerator.is_local_main_process, ) for epoch in range(first_epoch, args.num_train_epochs): unet.train() if args.train_text_encoder: text_encoder_one.train() text_encoder_two.train() train_loss = 0.0 for step, batch in enumerate(train_dataloader): with accelerator.accumulate(unet): # Convert images to latent space if args.pretrained_vae_model_name_or_path is not None: pixel_values = batch["pixel_values"].to(dtype=weight_dtype) else: pixel_values = batch["pixel_values"] model_input = vae.encode(pixel_values).latent_dist.sample() model_input = model_input * vae.config.scaling_factor if args.pretrained_vae_model_name_or_path is None: model_input = model_input.to(weight_dtype) # Sample noise that we'll add to the latents noise = torch.randn_like(model_input) if args.noise_offset: # https://www.crosslabs.org//blog/diffusion-with-offset-noise noise += args.noise_offset * torch.randn( (model_input.shape[0], model_input.shape[1], 1, 1), device=model_input.device ) bsz = model_input.shape[0] # Sample a random timestep for each image timesteps = torch.randint( 0, noise_scheduler.config.num_train_timesteps, (bsz,), device=model_input.device ) timesteps = timesteps.long() # Add noise to the model input according to the noise magnitude at each timestep # (this is the forward diffusion process) noisy_model_input = noise_scheduler.add_noise(model_input, noise, timesteps) # time ids def compute_time_ids(original_size, crops_coords_top_left): # Adapted from pipeline.StableDiffusionXLPipeline._get_add_time_ids target_size = (args.resolution, args.resolution) add_time_ids = list(original_size + crops_coords_top_left + target_size) add_time_ids = torch.tensor([add_time_ids]) add_time_ids = add_time_ids.to(accelerator.device, dtype=weight_dtype) return add_time_ids add_time_ids = torch.cat( [compute_time_ids(s, c) for s, c in zip(batch["original_sizes"], batch["crop_top_lefts"])] ) # Predict the noise residual unet_added_conditions = {"time_ids": add_time_ids} prompt_embeds, pooled_prompt_embeds = encode_prompt( text_encoders=[text_encoder_one, text_encoder_two], tokenizers=None, prompt=None, text_input_ids_list=[batch["input_ids_one"], batch["input_ids_two"]], ) unet_added_conditions.update({"text_embeds": pooled_prompt_embeds}) model_pred = unet( noisy_model_input, timesteps, prompt_embeds, added_cond_kwargs=unet_added_conditions ).sample # Get the target for loss depending on the prediction type if args.prediction_type is not None: # set prediction_type of scheduler if defined noise_scheduler.register_to_config(prediction_type=args.prediction_type) if noise_scheduler.config.prediction_type == "epsilon": target = noise elif noise_scheduler.config.prediction_type == "v_prediction": target = noise_scheduler.get_velocity(model_input, noise, timesteps) else: raise ValueError(f"Unknown prediction type {noise_scheduler.config.prediction_type}") if args.snr_gamma is None: loss = F.mse_loss(model_pred.float(), target.float(), reduction="mean") else: # Compute loss-weights as per Section 3.4 of https://arxiv.org/abs/2303.09556. # Since we predict the noise instead of x_0, the original formulation is slightly changed. # This is discussed in Section 4.2 of the same paper. snr = compute_snr(noise_scheduler, timesteps) if noise_scheduler.config.prediction_type == "v_prediction": # Velocity objective requires that we add one to SNR values before we divide by them. snr = snr + 1 mse_loss_weights = ( torch.stack([snr, args.snr_gamma * torch.ones_like(timesteps)], dim=1).min(dim=1)[0] / snr ) loss = F.mse_loss(model_pred.float(), target.float(), reduction="none") loss = loss.mean(dim=list(range(1, len(loss.shape)))) * mse_loss_weights loss = loss.mean() # Gather the losses across all processes for logging (if we use distributed training). avg_loss = accelerator.gather(loss.repeat(args.train_batch_size)).mean() train_loss += avg_loss.item() / args.gradient_accumulation_steps # Backpropagate accelerator.backward(loss) if accelerator.sync_gradients: params_to_clip = ( itertools.chain(unet_lora_parameters, text_lora_parameters_one, text_lora_parameters_two) if args.train_text_encoder else unet_lora_parameters ) accelerator.clip_grad_norm_(params_to_clip, args.max_grad_norm) optimizer.step() lr_scheduler.step() optimizer.zero_grad() # Checks if the accelerator has performed an optimization step behind the scenes if accelerator.sync_gradients: progress_bar.update(1) global_step += 1 accelerator.log({"train_loss": train_loss}, step=global_step) train_loss = 0.0 if accelerator.is_main_process: if global_step % args.checkpointing_steps == 0: # _before_ saving state, check if this save would set us over the `checkpoints_total_limit` if args.checkpoints_total_limit is not None: checkpoints = os.listdir(args.output_dir) checkpoints = [d for d in checkpoints if d.startswith("checkpoint")] checkpoints = sorted(checkpoints, key=lambda x: int(x.split("-")[1])) # before we save the new checkpoint, we need to have at _most_ `checkpoints_total_limit - 1` checkpoints if len(checkpoints) >= args.checkpoints_total_limit: num_to_remove = len(checkpoints) - args.checkpoints_total_limit + 1 removing_checkpoints = checkpoints[0:num_to_remove] logger.info( f"{len(checkpoints)} checkpoints already exist, removing {len(removing_checkpoints)} checkpoints" ) logger.info(f"removing checkpoints: {', '.join(removing_checkpoints)}") for removing_checkpoint in removing_checkpoints: removing_checkpoint = os.path.join(args.output_dir, removing_checkpoint) shutil.rmtree(removing_checkpoint) save_path = os.path.join(args.output_dir, f"checkpoint-{global_step}") accelerator.save_state(save_path) logger.info(f"Saved state to {save_path}") logs = {"step_loss": loss.detach().item(), "lr": lr_scheduler.get_last_lr()[0]} progress_bar.set_postfix(**logs) if global_step >= args.max_train_steps: break if accelerator.is_main_process: if args.validation_prompt is not None and epoch % args.validation_epochs == 0: logger.info( f"Running validation... \n Generating {args.num_validation_images} images with prompt:" f" {args.validation_prompt}." ) # create pipeline pipeline = StableDiffusionXLPipeline.from_pretrained( args.pretrained_model_name_or_path, vae=vae, text_encoder=accelerator.unwrap_model(text_encoder_one), text_encoder_2=accelerator.unwrap_model(text_encoder_two), unet=accelerator.unwrap_model(unet), revision=args.revision, torch_dtype=weight_dtype, ) pipeline = pipeline.to(accelerator.device) pipeline.set_progress_bar_config(disable=True) # run inference generator = torch.Generator(device=accelerator.device).manual_seed(args.seed) if args.seed else None pipeline_args = {"prompt": args.validation_prompt} with torch.cuda.amp.autocast(): images = [ pipeline(**pipeline_args, generator=generator).images[0] for _ in range(args.num_validation_images) ] for tracker in accelerator.trackers: if tracker.name == "tensorboard": np_images = np.stack([np.asarray(img) for img in images]) tracker.writer.add_images("validation", np_images, epoch, dataformats="NHWC") if tracker.name == "wandb": tracker.log( { "validation": [ wandb.Image(image, caption=f"{i}: {args.validation_prompt}") for i, image in enumerate(images) ] } ) del pipeline torch.cuda.empty_cache() # Save the lora layers accelerator.wait_for_everyone() if accelerator.is_main_process: unet = accelerator.unwrap_model(unet) unet_lora_layers = unet_attn_processors_state_dict(unet) if args.train_text_encoder: text_encoder_one = accelerator.unwrap_model(text_encoder_one) text_encoder_lora_layers = text_encoder_lora_state_dict(text_encoder_one) text_encoder_two = accelerator.unwrap_model(text_encoder_two) text_encoder_2_lora_layers = text_encoder_lora_state_dict(text_encoder_two) else: text_encoder_lora_layers = None text_encoder_2_lora_layers = None StableDiffusionXLPipeline.save_lora_weights( save_directory=args.output_dir, unet_lora_layers=unet_lora_layers, text_encoder_lora_layers=text_encoder_lora_layers, text_encoder_2_lora_layers=text_encoder_2_lora_layers, ) del unet del text_encoder_one del text_encoder_two del text_encoder_lora_layers del text_encoder_2_lora_layers torch.cuda.empty_cache() # Final inference # Load previous pipeline pipeline = StableDiffusionXLPipeline.from_pretrained( args.pretrained_model_name_or_path, vae=vae, revision=args.revision, torch_dtype=weight_dtype ) pipeline = pipeline.to(accelerator.device) # load attention processors pipeline.load_lora_weights(args.output_dir) # run inference images = [] if args.validation_prompt and args.num_validation_images > 0: generator = torch.Generator(device=accelerator.device).manual_seed(args.seed) if args.seed else None images = [ pipeline(args.validation_prompt, num_inference_steps=25, generator=generator).images[0] for _ in range(args.num_validation_images) ] for tracker in accelerator.trackers: if tracker.name == "tensorboard": np_images = np.stack([np.asarray(img) for img in images]) tracker.writer.add_images("test", np_images, epoch, dataformats="NHWC") if tracker.name == "wandb": tracker.log( { "test": [ wandb.Image(image, caption=f"{i}: {args.validation_prompt}") for i, image in enumerate(images) ] } ) if args.push_to_hub: save_model_card( repo_id, images=images, base_model=args.pretrained_model_name_or_path, dataset_name=args.dataset_name, train_text_encoder=args.train_text_encoder, repo_folder=args.output_dir, vae_path=args.pretrained_vae_model_name_or_path, ) upload_folder( repo_id=repo_id, folder_path=args.output_dir, commit_message="End of training", ignore_patterns=["step_*", "epoch_*"], ) accelerator.end_training() if __name__ == "__main__": args = parse_args() main(args)