multi-subject-dreambooth-inpainting with 🤗 datasets (#6378)

* files added

* fixing code quality

* fixing code quality

* fixing code quality

* fixing code quality

* sorted import block

* seperated import wandb

* ruff on script

---------

Co-authored-by: Sayak Paul <spsayakpaul@gmail.com>
This commit is contained in:
gzguevara
2023-12-29 05:03:49 +01:00
committed by sayakpaul
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# Multi Subject Dreambooth for Inpainting Models
Please note that this project is not actively maintained. However, you can open an issue and tag @gzguevara.
[DreamBooth](https://arxiv.org/abs/2208.12242) is a method to personalize text2image models like stable diffusion given just a few(3~5) images of a subject. This project consists of **two parts**. Training Stable Diffusion for inpainting requieres prompt-image-mask pairs. The Unet of inpainiting models have 5 additional input channels (4 for the encoded masked-image and 1 for the mask itself).
**The first part**, the `multi_inpaint_dataset.ipynb` notebook, demonstrates how make a 🤗 dataset of prompt-image-mask pairs. You can, however, skip the first part and move straight to the second part with the example datasets in this project. ([cat toy dataset masked](https://huggingface.co/datasets/gzguevara/cat_toy_masked), [mr. potato head dataset masked](https://huggingface.co/datasets/gzguevara/mr_potato_head_masked))
**The second part**, the `train_multi_subject_inpainting.py` training script, demonstrates how to implement a training procedure for one or more subjects and adapt it for stable diffusion for inpainting.
## 1. Data Collection: Make Prompt-Image-Mask Pairs
Earlier training scripts have provided approaches like random masking for the training images. This project provides a notebook for more precise mask setting.
The notebook can be found here: [![Open In Colab](https://colab.research.google.com/assets/colab-badge.svg)](https://colab.research.google.com/drive/1JNEASI_B7pLW1srxhgln6nM0HoGAQT32?usp=sharing)
The `multi_inpaint_dataset.ipynb` notebook, takes training & validation images, on which the user draws masks and provides prompts to make a prompt-image-mask pairs. This ensures that during training, the loss is computed on the area masking the object of interest, rather than on random areas. Moreover, the `multi_inpaint_dataset.ipynb` notebook allows you to build a validation dataset with corresponding masks for monitoring the training process. Example below:
![train_val_pairs](https://drive.google.com/uc?id=1PzwH8E3icl_ubVmA19G0HZGLImFX3x5I)
You can build multiple datasets for every subject and upload them to the 🤗 hub. Later, when launching the training script you can indicate the paths of the datasets, on which you would like to finetune Stable Diffusion for inpaining.
## 2. Train Multi Subject Dreambooth for Inpainting
### 2.1. Setting The Training Configuration
Before launching the training script, make sure to select the inpainting the target model, the output directory and the 🤗 datasets.
```bash
export MODEL_NAME="runwayml/stable-diffusion-inpainting"
export OUTPUT_DIR="path-to-save-model"
export DATASET_1="gzguevara/mr_potato_head_masked"
export DATASET_2="gzguevara/cat_toy_masked"
... # Further paths to 🤗 datasets
```
### 2.2. Launching The Training Script
```bash
accelerate launch train_multi_subject_dreambooth_inpaint.py \
--pretrained_model_name_or_path=$MODEL_NAME \
--instance_data_dir $DATASET_1 $DATASET_2 \
--output_dir=$OUTPUT_DIR \
--resolution=512 \
--train_batch_size=1 \
--gradient_accumulation_steps=2 \
--learning_rate=3e-6 \
--max_train_steps=500 \
--report_to_wandb
```
### 2.3. Fine-tune text encoder with the UNet.
The script also allows to fine-tune the `text_encoder` along with the `unet`. It's been observed experimentally that fine-tuning `text_encoder` gives much better results especially on faces.
Pass the `--train_text_encoder` argument to the script to enable training `text_encoder`.
___Note: Training text encoder requires more memory, with this option the training won't fit on 16GB GPU. It needs at least 24GB VRAM.___
```bash
accelerate launch train_multi_subject_dreambooth_inpaint.py \
--pretrained_model_name_or_path=$MODEL_NAME \
--instance_data_dir $DATASET_1 $DATASET_2 \
--output_dir=$OUTPUT_DIR \
--resolution=512 \
--train_batch_size=1 \
--gradient_accumulation_steps=2 \
--learning_rate=2e-6 \
--max_train_steps=500 \
--report_to_wandb \
--train_text_encoder
```
## 3. Results
A [![Weights & Biases](https://img.shields.io/badge/Weights%20&%20Biases-Report-blue)](https://wandb.ai/gzguevara/uncategorized/reports/Multi-Subject-Dreambooth-for-Inpainting--Vmlldzo2MzY5NDQ4) is provided showing the training progress by every 50 steps. Note, the reported weights & baises run was performed on a A100 GPU with the following stetting:
```bash
accelerate launch train_multi_subject_dreambooth_inpaint.py \
--pretrained_model_name_or_path=$MODEL_NAME \
--instance_data_dir $DATASET_1 $DATASET_2 \
--output_dir=$OUTPUT_DIR \
--resolution=512 \
--train_batch_size=10 \
--gradient_accumulation_steps=1 \
--learning_rate=1e-6 \
--max_train_steps=500 \
--report_to_wandb \
--train_text_encoder
```
Here you can see the target objects on my desk and next to my plant:
![Results](https://drive.google.com/uc?id=1kQisOiiF5cj4rOYjdq8SCZenNsUP2aK0)
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accelerate>=0.16.0
torchvision
transformers>=4.25.1
datasets>=2.16.0
wandb>=0.16.1
ftfy
tensorboard
Jinja2
@@ -0,0 +1,661 @@
import argparse
import copy
import itertools
import logging
import math
import os
import random
from pathlib import Path
import numpy as np
import torch
import torch.nn.functional as F
import torch.utils.checkpoint
from accelerate import Accelerator
from accelerate.logging import get_logger
from accelerate.utils import ProjectConfiguration, set_seed
from datasets import concatenate_datasets, load_dataset
from PIL import Image
from torch.utils.data import Dataset
from torchvision import transforms
from tqdm.auto import tqdm
from transformers import CLIPTextModel, CLIPTokenizer
from diffusers import (
AutoencoderKL,
DDPMScheduler,
StableDiffusionInpaintPipeline,
UNet2DConditionModel,
)
from diffusers.optimization import get_scheduler
from diffusers.utils import check_min_version, is_wandb_available
if is_wandb_available():
import wandb
# Will error if the minimal version of diffusers is not installed. Remove at your own risks.
check_min_version("0.13.0.dev0")
logger = get_logger(__name__)
def parse_args():
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("--instance_data_dir", nargs="+", help="Instance data directories")
parser.add_argument(
"--output_dir",
type=str,
default="text-inversion-model",
help="The output directory where the model predictions and checkpoints will be written.",
)
parser.add_argument("--seed", type=int, default=None, help="A seed for reproducible training.")
parser.add_argument(
"--resolution",
type=int,
default=512,
help=(
"The resolution for input images, all the images in the train/validation dataset will be resized to this"
" resolution"
),
)
parser.add_argument(
"--train_text_encoder", default=False, action="store_true", help="Whether to train the text encoder"
)
parser.add_argument(
"--train_batch_size", type=int, default=4, help="Batch size (per device) for the training dataloader."
)
parser.add_argument(
"--sample_batch_size", type=int, default=4, help="Batch size (per device) for sampling images."
)
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(
"--gradient_accumulation_steps",
type=int,
default=1,
help="Number of updates steps to accumulate before performing a backward/update pass.",
)
parser.add_argument(
"--learning_rate",
type=float,
default=5e-6,
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("--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(
"--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(
"--mixed_precision",
type=str,
default="no",
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."
),
)
parser.add_argument(
"--checkpointing_steps",
type=int,
default=1000,
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 suitable for resuming training"
" using `--resume_from_checkpoint`."
),
)
parser.add_argument(
"--checkpointing_from",
type=int,
default=1000,
help=("Start to checkpoint from step"),
)
parser.add_argument(
"--validation_steps",
type=int,
default=50,
help=(
"Run validation every X steps. Validation consists of running the prompt"
" `args.validation_prompt` multiple times: `args.num_validation_images`"
" and logging the images."
),
)
parser.add_argument(
"--validation_from",
type=int,
default=0,
help=("Start to validate from step"),
)
parser.add_argument(
"--checkpoints_total_limit",
type=int,
default=None,
help=(
"Max number of checkpoints to store. Passed as `total_limit` to the `Accelerator` `ProjectConfiguration`."
" See Accelerator::save_state https://huggingface.co/docs/accelerate/package_reference/accelerator#accelerate.Accelerator.save_state"
" for more docs"
),
)
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(
"--validation_project_name",
type=str,
default=None,
help="The w&b name.",
)
parser.add_argument(
"--report_to_wandb", default=False, action="store_true", help="Whether to report to weights and biases"
)
args = parser.parse_args()
return args
def prepare_mask_and_masked_image(image, mask):
image = np.array(image.convert("RGB"))
image = image[None].transpose(0, 3, 1, 2)
image = torch.from_numpy(image).to(dtype=torch.float32) / 127.5 - 1.0
mask = np.array(mask.convert("L"))
mask = mask.astype(np.float32) / 255.0
mask = mask[None, None]
mask[mask < 0.5] = 0
mask[mask >= 0.5] = 1
mask = torch.from_numpy(mask)
masked_image = image * (mask < 0.5)
return mask, masked_image
class DreamBoothDataset(Dataset):
def __init__(
self,
tokenizer,
datasets_paths,
):
self.tokenizer = tokenizer
self.datasets_paths = (datasets_paths,)
self.datasets = [load_dataset(dataset_path) for dataset_path in self.datasets_paths[0]]
self.train_data = concatenate_datasets([dataset["train"] for dataset in self.datasets])
self.test_data = concatenate_datasets([dataset["test"] for dataset in self.datasets])
self.image_normalize = transforms.Compose(
[
transforms.ToTensor(),
transforms.Normalize([0.5], [0.5]),
]
)
def set_image(self, img, switch):
if img.mode not in ["RGB", "L"]:
img = img.convert("RGB")
if switch:
img = img.transpose(Image.FLIP_LEFT_RIGHT)
img = img.resize((512, 512), Image.BILINEAR)
return img
def __len__(self):
return len(self.train_data)
def __getitem__(self, index):
# Lettings
example = {}
img_idx = index % len(self.train_data)
switch = random.choice([True, False])
# Load image
image = self.set_image(self.train_data[img_idx]["image"], switch)
# Normalize image
image_norm = self.image_normalize(image)
# Tokenise prompt
tokenized_prompt = self.tokenizer(
self.train_data[img_idx]["prompt"],
padding="do_not_pad",
truncation=True,
max_length=self.tokenizer.model_max_length,
).input_ids
# Load masks for image
masks = [
self.set_image(self.train_data[img_idx][key], switch) for key in self.train_data[img_idx] if "mask" in key
]
# Build example
example["PIL_image"] = image
example["instance_image"] = image_norm
example["instance_prompt_id"] = tokenized_prompt
example["instance_masks"] = masks
return example
def weighted_mask(masks):
# Convert each mask to a NumPy array and ensure it's binary
mask_arrays = [np.array(mask) / 255 for mask in masks] # Normalizing to 0-1 range
# Generate random weights and apply them to each mask
weights = [random.random() for _ in masks]
weights = [weight / sum(weights) for weight in weights]
weighted_masks = [mask * weight for mask, weight in zip(mask_arrays, weights)]
# Sum the weighted masks
summed_mask = np.sum(weighted_masks, axis=0)
# Apply a threshold to create the final mask
threshold = 0.5 # This threshold can be adjusted
result_mask = summed_mask >= threshold
# Convert the result back to a PIL image
return Image.fromarray(result_mask.astype(np.uint8) * 255)
def collate_fn(examples, tokenizer):
input_ids = [example["instance_prompt_id"] for example in examples]
pixel_values = [example["instance_image"] for example in examples]
masks, masked_images = [], []
for example in examples:
# generate a random mask
mask = weighted_mask(example["instance_masks"])
# prepare mask and masked image
mask, masked_image = prepare_mask_and_masked_image(example["PIL_image"], mask)
masks.append(mask)
masked_images.append(masked_image)
pixel_values = torch.stack(pixel_values).to(memory_format=torch.contiguous_format).float()
masks = torch.stack(masks)
masked_images = torch.stack(masked_images)
input_ids = tokenizer.pad({"input_ids": input_ids}, padding=True, return_tensors="pt").input_ids
batch = {"input_ids": input_ids, "pixel_values": pixel_values, "masks": masks, "masked_images": masked_images}
return batch
def log_validation(pipeline, text_encoder, unet, val_pairs, accelerator):
# update pipeline (note: unet and vae are loaded again in float32)
pipeline.text_encoder = accelerator.unwrap_model(text_encoder)
pipeline.unet = accelerator.unwrap_model(unet)
with torch.autocast("cuda"):
val_results = [{"data_or_path": pipeline(**pair).images[0], "caption": pair["prompt"]} for pair in val_pairs]
torch.cuda.empty_cache()
wandb.log({"validation": [wandb.Image(**val_result) for val_result in val_results]})
def checkpoint(args, global_step, accelerator):
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}")
def main():
args = parse_args()
project_config = ProjectConfiguration(
total_limit=args.checkpoints_total_limit,
project_dir=args.output_dir,
logging_dir=Path(args.output_dir, args.logging_dir),
)
accelerator = Accelerator(
gradient_accumulation_steps=args.gradient_accumulation_steps,
mixed_precision=args.mixed_precision,
project_config=project_config,
log_with="wandb" if args.report_to_wandb else None,
)
if args.report_to_wandb and not is_wandb_available():
raise ImportError("Make sure to install wandb if you want to use it for logging during training.")
if args.seed is not None:
set_seed(args.seed)
# 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)
# Load the tokenizer & models and create wrapper for stable diffusion
tokenizer = CLIPTokenizer.from_pretrained(args.pretrained_model_name_or_path, subfolder="tokenizer")
text_encoder = CLIPTextModel.from_pretrained(
args.pretrained_model_name_or_path, subfolder="text_encoder"
).requires_grad_(args.train_text_encoder)
vae = AutoencoderKL.from_pretrained(args.pretrained_model_name_or_path, subfolder="vae").requires_grad_(False)
unet = UNet2DConditionModel.from_pretrained(args.pretrained_model_name_or_path, subfolder="unet")
if args.scale_lr:
args.learning_rate = (
args.learning_rate * args.gradient_accumulation_steps * args.train_batch_size * accelerator.num_processes
)
optimizer = torch.optim.AdamW(
params=itertools.chain(unet.parameters(), text_encoder.parameters())
if args.train_text_encoder
else unet.parameters(),
lr=args.learning_rate,
betas=(args.adam_beta1, args.adam_beta2),
weight_decay=args.adam_weight_decay,
eps=args.adam_epsilon,
)
noise_scheduler = DDPMScheduler.from_pretrained(args.pretrained_model_name_or_path, subfolder="scheduler")
train_dataset = DreamBoothDataset(
tokenizer=tokenizer,
datasets_paths=args.instance_data_dir,
)
train_dataloader = torch.utils.data.DataLoader(
train_dataset,
batch_size=args.train_batch_size,
shuffle=True,
collate_fn=lambda examples: collate_fn(examples, tokenizer),
)
# Scheduler and math around the number of training steps.
num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps)
lr_scheduler = get_scheduler(
args.lr_scheduler,
optimizer=optimizer,
num_warmup_steps=args.lr_warmup_steps * accelerator.num_processes,
num_training_steps=args.max_train_steps * accelerator.num_processes,
)
if args.train_text_encoder:
unet, text_encoder, optimizer, train_dataloader, lr_scheduler = accelerator.prepare(
unet, text_encoder, optimizer, train_dataloader, lr_scheduler
)
else:
unet, optimizer, train_dataloader, lr_scheduler = accelerator.prepare(
unet, optimizer, train_dataloader, lr_scheduler
)
accelerator.register_for_checkpointing(lr_scheduler)
if args.mixed_precision == "fp16":
weight_dtype = torch.float16
elif args.mixed_precision == "bf16":
weight_dtype = torch.bfloat16
else:
weight_dtype = torch.float32
# Move text_encode and vae to gpu.
# For mixed precision training we cast the text_encoder and vae weights to half-precision
# as these models are only used for inference, keeping weights in full precision is not required.
vae.to(accelerator.device, dtype=weight_dtype)
if not args.train_text_encoder:
text_encoder.to(accelerator.device, dtype=weight_dtype)
# 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)
# Afterwards we calculate our number of training epochs
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:
tracker_config = vars(copy.deepcopy(args))
accelerator.init_trackers(args.validation_project_name, config=tracker_config)
# create validation pipeline (note: unet and vae are loaded again in float32)
val_pipeline = StableDiffusionInpaintPipeline.from_pretrained(
args.pretrained_model_name_or_path,
tokenizer=tokenizer,
text_encoder=text_encoder,
unet=unet,
vae=vae,
torch_dtype=weight_dtype,
safety_checker=None,
)
val_pipeline.set_progress_bar_config(disable=True)
# prepare validation dataset
val_pairs = [
{
"image": example["image"],
"mask_image": mask,
"prompt": example["prompt"],
}
for example in train_dataset.test_data
for mask in [example[key] for key in example if "mask" in key]
]
# 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:
for model in models:
sub_dir = "unet" if isinstance(model, type(accelerator.unwrap_model(unet))) else "text_encoder"
model.save_pretrained(os.path.join(output_dir, sub_dir))
# make sure to pop weight so that corresponding model is not saved again
weights.pop()
accelerator.register_save_state_pre_hook(save_model_hook)
print()
# Train!
total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps
logger.info("***** Running training *****")
logger.info(f" Num batches each epoch = {len(train_dataloader)}")
logger.info(f" Num Epochs = {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
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
else:
accelerator.print(f"Resuming from checkpoint {path}")
accelerator.load_state(os.path.join(args.output_dir, path))
global_step = int(path.split("-")[1])
resume_global_step = global_step * args.gradient_accumulation_steps
first_epoch = global_step // num_update_steps_per_epoch
resume_step = resume_global_step % (num_update_steps_per_epoch * args.gradient_accumulation_steps)
# Only show the progress bar once on each machine.
progress_bar = tqdm(range(global_step, args.max_train_steps), disable=not accelerator.is_local_main_process)
progress_bar.set_description("Steps")
for epoch in range(first_epoch, num_train_epochs):
unet.train()
for step, batch in enumerate(train_dataloader):
# Skip steps until we reach the resumed step
if args.resume_from_checkpoint and epoch == first_epoch and step < resume_step:
if step % args.gradient_accumulation_steps == 0:
progress_bar.update(1)
continue
with accelerator.accumulate(unet):
# Convert images to latent space
latents = vae.encode(batch["pixel_values"].to(dtype=weight_dtype)).latent_dist.sample()
latents = latents * vae.config.scaling_factor
# Convert masked images to latent space
masked_latents = vae.encode(
batch["masked_images"].reshape(batch["pixel_values"].shape).to(dtype=weight_dtype)
).latent_dist.sample()
masked_latents = masked_latents * vae.config.scaling_factor
masks = batch["masks"]
# resize the mask to latents shape as we concatenate the mask to the latents
mask = torch.stack(
[
torch.nn.functional.interpolate(mask, size=(args.resolution // 8, args.resolution // 8))
for mask in masks
]
)
mask = mask.reshape(-1, 1, args.resolution // 8, args.resolution // 8)
# Sample noise that we'll add to the latents
noise = torch.randn_like(latents)
bsz = latents.shape[0]
# Sample a random timestep for each image
timesteps = torch.randint(0, noise_scheduler.config.num_train_timesteps, (bsz,), device=latents.device)
timesteps = timesteps.long()
# Add noise to the latents according to the noise magnitude at each timestep
# (this is the forward diffusion process)
noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps)
# concatenate the noised latents with the mask and the masked latents
latent_model_input = torch.cat([noisy_latents, mask, masked_latents], dim=1)
# Get the text embedding for conditioning
encoder_hidden_states = text_encoder(batch["input_ids"])[0]
# Predict the noise residual
noise_pred = unet(latent_model_input, timesteps, encoder_hidden_states).sample
# Get the target for loss depending on the prediction type
if noise_scheduler.config.prediction_type == "epsilon":
target = noise
elif noise_scheduler.config.prediction_type == "v_prediction":
target = noise_scheduler.get_velocity(latents, noise, timesteps)
else:
raise ValueError(f"Unknown prediction type {noise_scheduler.config.prediction_type}")
loss = F.mse_loss(noise_pred.float(), target.float(), reduction="mean")
accelerator.backward(loss)
if accelerator.sync_gradients:
params_to_clip = (
itertools.chain(unet.parameters(), text_encoder.parameters())
if args.train_text_encoder
else unet.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
if accelerator.is_main_process:
if (
global_step % args.validation_steps == 0
and global_step >= args.validation_from
and args.report_to_wandb
):
log_validation(
val_pipeline,
text_encoder,
unet,
val_pairs,
accelerator,
)
if global_step % args.checkpointing_steps == 0 and global_step >= args.checkpointing_from:
checkpoint(
args,
global_step,
accelerator,
)
# Step logging
logs = {"loss": loss.detach().item(), "lr": lr_scheduler.get_last_lr()[0]}
progress_bar.set_postfix(**logs)
accelerator.log(logs, step=global_step)
if global_step >= args.max_train_steps:
break
accelerator.wait_for_everyone()
# Terminate training
accelerator.end_training()
if __name__ == "__main__":
main()