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train_baseline.py
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#!/usr/bin/env python
# coding=utf-8
# Copyright 2024 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
import jittor as jt
import jittor.nn as nn
import argparse
import copy
import logging
import math
import os
import warnings
from pathlib import Path
import numpy as np
import transformers
from peft import LoraConfig
from peft.utils import get_peft_model_state_dict
from PIL import Image
from PIL.ImageOps import exif_transpose
from jittor import transform
from jittor.compatibility.optim import AdamW
from jittor.compatibility.utils.data import Dataset, DataLoader
from tqdm.auto import tqdm
from transformers import AutoTokenizer, PretrainedConfig
import diffusers
from JDiffusion import (
AutoencoderKL,
UNet2DConditionModel,
)
from diffusers import DDPMScheduler
from diffusers.loaders import LoraLoaderMixin
from diffusers.optimization import get_scheduler
from diffusers.utils import (
convert_state_dict_to_diffusers,
)
def import_model_class_from_model_name_or_path(pretrained_model_name_or_path: str, revision: str):
text_encoder_config = PretrainedConfig.from_pretrained(
pretrained_model_name_or_path,
subfolder="text_encoder",
revision=revision,
)
model_class = text_encoder_config.architectures[0]
if model_class == "CLIPTextModel":
from transformers import CLIPTextModel
return CLIPTextModel
elif model_class == "T5EncoderModel":
from transformers import T5EncoderModel
return T5EncoderModel
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(
"--num_process",
type=int,
default=1
)
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(
"--revision",
type=str,
default=None,
required=False,
help="Revision of pretrained model identifier from huggingface.co/models.",
)
parser.add_argument(
"--variant",
type=str,
default=None,
help="Variant of the model files of the pretrained model identifier from huggingface.co/models, 'e.g.' fp16",
)
parser.add_argument(
"--tokenizer_name",
type=str,
default=None,
help="Pretrained tokenizer name or path if not the same as model_name",
)
parser.add_argument(
"--instance_data_dir",
type=str,
default=None,
required=True,
help="A folder containing the training data of instance images.",
)
parser.add_argument(
"--class_data_dir",
type=str,
default=None,
required=False,
help="A folder containing the training data of class images.",
)
parser.add_argument(
"--instance_prompt",
type=str,
default=None,
required=True,
help="The prompt with identifier specifying the instance",
)
parser.add_argument(
"--class_prompt",
type=str,
default=None,
help="The prompt to specify images in the same class as provided instance images.",
)
parser.add_argument(
"--with_prior_preservation",
default=False,
action="store_true",
help="Flag to add prior preservation loss.",
)
parser.add_argument("--prior_loss_weight", type=float, default=1.0, help="The weight of prior preservation loss.")
parser.add_argument(
"--num_class_images",
type=int,
default=100,
help=(
"Minimal class images for prior preservation loss. If there are not enough images already present in"
" class_data_dir, additional images will be sampled with class_prompt."
),
)
parser.add_argument(
"--output_dir",
type=str,
default="lora-dreambooth-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(
"--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(
"--train_batch_size", type=int, default=5, 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("--num_train_epochs", type=int, default=1)
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(
"--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=5e-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(
"--lr_num_cycles",
type=int,
default=1,
help="Number of hard resets of the lr in cosine_with_restarts scheduler.",
)
parser.add_argument("--lr_power", type=float, default=1.0, help="Power factor of the polynomial scheduler.")
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("--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("--hub_token", type=str, default=None, help="The token to use to push to the Model Hub.")
parser.add_argument(
"--tokenizer_max_length",
type=int,
default=None,
required=False,
help="The maximum length of the tokenizer. If not set, will default to the tokenizer's max length.",
)
parser.add_argument(
"--text_encoder_use_attention_mask",
action="store_true",
required=False,
help="Whether to use attention mask for the text encoder",
)
parser.add_argument(
"--validation_images",
required=False,
default=None,
nargs="+",
help="Optional set of images to use for validation. Used when the target pipeline takes an initial image as input such as when training image variation or superresolution.",
)
parser.add_argument(
"--class_labels_conditioning",
required=False,
default=None,
help="The optional `class_label` conditioning to pass to the unet, available values are `timesteps`.",
)
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()
# logger is not available yet
if args.class_data_dir is not None:
warnings.warn("You need not use --class_data_dir without --with_prior_preservation.")
if args.class_prompt is not None:
warnings.warn("You need not use --class_prompt without --with_prior_preservation.")
return args
class DreamBoothDataset(Dataset):
"""
A dataset to prepare the instance and class images with the prompts for fine-tuning the model.
It pre-processes the images and the tokenizes prompts.
"""
def __init__(
self,
instance_data_root,
instance_prompt,
tokenizer,
class_data_root=None,
class_prompt=None,
class_num=None,
size=512,
center_crop=False,
encoder_hidden_states=None,
class_prompt_encoder_hidden_states=None,
tokenizer_max_length=None,
):
self.size = size
self.center_crop = center_crop
self.tokenizer = tokenizer
self.encoder_hidden_states = encoder_hidden_states
self.class_prompt_encoder_hidden_states = class_prompt_encoder_hidden_states
self.tokenizer_max_length = tokenizer_max_length
self.instance_data_root = Path(instance_data_root)
if not self.instance_data_root.exists():
raise ValueError("Instance images root doesn't exists.")
self.instance_images_path = list(Path(instance_data_root).iterdir())
self.num_instance_images = len(self.instance_images_path)
# self.instance_prompt = instance_prompt
# TODO: Add image names to the instance_prompt
# 法1:形式:<class> in style_<num>
self.instance_prompt = [f"{image.stem} in {instance_prompt}" for image in self.instance_images_path]
# # 法2:形式:a sks <style>
# self.instance_prompt = [f"a sks {image.stem}" for image in self.instance_images_path]
self._length = self.num_instance_images
if class_data_root is not None:
self.class_data_root = Path(class_data_root)
self.class_data_root.mkdir(parents=True, exist_ok=True)
self.class_images_path = list(self.class_data_root.iterdir())
if class_num is not None:
self.num_class_images = min(len(self.class_images_path), class_num)
else:
self.num_class_images = len(self.class_images_path)
self._length = max(self.num_class_images, self.num_instance_images)
self.class_prompt = class_prompt
# # TODO:Add image names to the class_prompt
# self.class_prompt = [f"{image.stem}: {class_prompt}" for image in self.class_images_path]
else:
self.class_data_root = None
self.image_transforms = transform.Compose(
[
transform.Resize(size),
transform.CenterCrop(size) if center_crop else transform.RandomCrop(size),
transform.ToTensor(),
transform.ImageNormalize([0.5], [0.5]),
]
)
def __len__(self):
return self._length
def __getitem__(self, index):
example = {}
instance_image = Image.open(self.instance_images_path[index % self.num_instance_images])
instance_image = exif_transpose(instance_image)
if not instance_image.mode == "RGB":
instance_image = instance_image.convert("RGB")
example["instance_images"] = self.image_transforms(instance_image)
if self.encoder_hidden_states is not None:
example["instance_prompt_ids"] = self.encoder_hidden_states
else:
# text_inputs = tokenize_prompt(
# self.tokenizer, self.instance_prompt, tokenizer_max_length=self.tokenizer_max_length
# )
# TODO:Use the modified instance_prompt with image names
text_inputs = tokenize_prompt(
self.tokenizer, self.instance_prompt[index % self.num_instance_images], tokenizer_max_length=self.tokenizer_max_length
)
# print(f'index: {index}, text_inputs: {text_inputs}')
example["instance_prompt_ids"] = text_inputs.input_ids
example["instance_attention_mask"] = text_inputs.attention_mask
if self.class_data_root:
class_image = Image.open(self.class_images_path[index % self.num_class_images])
class_image = exif_transpose(class_image)
if not class_image.mode == "RGB":
class_image = class_image.convert("RGB")
example["class_images"] = self.image_transforms(class_image)
if self.class_prompt_encoder_hidden_states is not None:
example["class_prompt_ids"] = self.class_prompt_encoder_hidden_states
else:
class_text_inputs = tokenize_prompt(
self.tokenizer, self.class_prompt, tokenizer_max_length=self.tokenizer_max_length
)
example["class_prompt_ids"] = class_text_inputs.input_ids
example["class_attention_mask"] = class_text_inputs.attention_mask
return example
def collate_fn(examples, with_prior_preservation=False):
has_attention_mask = "instance_attention_mask" in examples[0]
input_ids = [example["instance_prompt_ids"] for example in examples]
pixel_values = [example["instance_images"] for example in examples]
if has_attention_mask:
attention_mask = [example["instance_attention_mask"] for example in examples]
pixel_values = jt.stack(pixel_values)
pixel_values = pixel_values.float()
input_ids = jt.cat(input_ids, dim=0)
batch = {
"input_ids": input_ids,
"pixel_values": pixel_values,
}
if has_attention_mask:
batch["attention_mask"] = attention_mask
return batch
class PromptDataset(Dataset):
"A simple dataset to prepare the prompts to generate class images on multiple GPUs."
def __init__(self, prompt, num_samples):
self.prompt = prompt
self.num_samples = num_samples
def __len__(self):
return self.num_samples
def __getitem__(self, index):
example = {}
example["prompt"] = self.prompt
example["index"] = index
return example
def tokenize_prompt(tokenizer, prompt, tokenizer_max_length=None):
if tokenizer_max_length is not None:
max_length = tokenizer_max_length
else:
max_length = tokenizer.model_max_length
text_inputs = tokenizer(
prompt,
truncation=True,
padding="max_length",
max_length=max_length,
return_tensors="pt",
)
return text_inputs
def encode_prompt(text_encoder, input_ids, attention_mask, text_encoder_use_attention_mask=None):
text_input_ids = input_ids.to(text_encoder.device)
if text_encoder_use_attention_mask:
attention_mask = attention_mask.to(text_encoder.device)
else:
attention_mask = None
prompt_embeds = text_encoder(
text_input_ids,
attention_mask=attention_mask,
return_dict=False,
)
prompt_embeds = prompt_embeds[0]
return prompt_embeds
def main(args):
jt.flags.use_cuda = 1
# 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,
)
transformers.utils.logging.set_verbosity_warning()
diffusers.utils.logging.set_verbosity_info()
# Handle the repository creation
if args.output_dir is not None:
os.makedirs(args.output_dir, exist_ok=True)
# Load the tokenizer
if args.tokenizer_name:
tokenizer = AutoTokenizer.from_pretrained(args.tokenizer_name, revision=args.revision, use_fast=False)
elif args.pretrained_model_name_or_path:
tokenizer = AutoTokenizer.from_pretrained(
args.pretrained_model_name_or_path,
subfolder="tokenizer",
revision=args.revision,
use_fast=False,
)
# import correct text encoder class
text_encoder_cls = import_model_class_from_model_name_or_path(args.pretrained_model_name_or_path, args.revision)
# Load scheduler and models
noise_scheduler = DDPMScheduler.from_pretrained(args.pretrained_model_name_or_path, subfolder="scheduler")
text_encoder = text_encoder_cls.from_pretrained(
args.pretrained_model_name_or_path, subfolder="text_encoder", revision=args.revision
)
vae = AutoencoderKL.from_pretrained(
args.pretrained_model_name_or_path, subfolder="vae", 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
#if vae is not None:
# vae.requires_grad_(False)
#text_encoder.requires_grad_(False)
#unet.requires_grad_(False)
# For mixed precision training we cast all non-trainable weights (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 = jt.float32
for name, param in unet.named_parameters():
assert param.requires_grad == False, name
# now we will add new LoRA weights to the attention layers
# TODO: lora
unet_lora_config = LoraConfig(
r=args.rank,
lora_alpha=args.rank,
init_lora_weights="gaussian",
target_modules=["to_k", "to_q", "to_v", "to_out.0", "add_k_proj", "add_v_proj", ],
)
unet.add_adapter(unet_lora_config)
# vae_lora_config = unet_lora_config
# vae.add_adapter(vae_lora_config)
# print(vae)
# Optimizer creation
optimizer = AdamW(
list(unet.parameters()),
lr=args.learning_rate,
betas=(args.adam_beta1, args.adam_beta2),
weight_decay=args.adam_weight_decay,
eps=args.adam_epsilon,
)
pre_computed_encoder_hidden_states = None
pre_computed_class_prompt_encoder_hidden_states = None
# Dataset and DataLoaders creation:
train_dataset = DreamBoothDataset(
instance_data_root=args.instance_data_dir,
instance_prompt=args.instance_prompt,
class_data_root=args.class_data_dir if args.with_prior_preservation else None,
class_prompt=args.class_prompt,
class_num=args.num_class_images,
tokenizer=tokenizer,
size=args.resolution,
center_crop=args.center_crop,
encoder_hidden_states=pre_computed_encoder_hidden_states,
class_prompt_encoder_hidden_states=pre_computed_class_prompt_encoder_hidden_states,
tokenizer_max_length=args.tokenizer_max_length,
)
train_dataloader = DataLoader(
train_dataset,
batch_size=args.train_batch_size,
shuffle=True,
collate_fn=lambda examples: collate_fn(examples, False),
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.num_process,
num_training_steps=args.max_train_steps * args.num_process,
num_cycles=args.lr_num_cycles,
power=args.lr_power,
)
# 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.
tracker_config = vars(copy.deepcopy(args))
tracker_config.pop("validation_images")
# Train!
total_batch_size = args.train_batch_size * args.num_process * args.gradient_accumulation_steps
print("***** Running training *****")
print(f" Num examples = {len(train_dataset)}")
print(f" Num batches each epoch = {len(train_dataloader)}")
print(f" Num Epochs = {args.num_train_epochs}")
print(f" Instantaneous batch size per device = {args.train_batch_size}")
print(f" Total train batch size (w. parallel, distributed & accumulation) = {total_batch_size}")
print(f" Gradient Accumulation steps = {args.gradient_accumulation_steps}")
print(f" Total optimization steps = {args.max_train_steps}")
global_step = 0
first_epoch = 0
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=False,
)
for epoch in range(first_epoch, args.num_train_epochs):
for step, batch in enumerate(train_dataloader):
# TODO: Forward process
pixel_values = batch["pixel_values"].to(dtype=weight_dtype)
# Convert images to latent space
# model_input.shape = (bsz, channels, height, width) = (1, 3, 512, 512)
model_input = vae.encode(pixel_values).latent_dist.sample()
# here, model_input.shape changed to (1, 4, 64, 64)
model_input = model_input * vae.config.scaling_factor
# Sample noise that we'll add to the latents
noise = jt.randn_like(model_input)
bsz, channels, height, width = model_input.shape
# Sample a random timestep for each image
timesteps = jt.randint(
0, noise_scheduler.config.num_train_timesteps, (bsz,),
).to(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)
# Get the text embedding for conditioning
# TODO: Reve
# batch["input_ids"]:编码自风格名(如“style_00”)
encoder_hidden_states = encode_prompt(
text_encoder,
batch["input_ids"], # input (string -> array)
batch["attention_mask"],
text_encoder_use_attention_mask=args.text_encoder_use_attention_mask,
)
if unet.config.in_channels == channels * 2:
noisy_model_input = jt.cat([noisy_model_input, noisy_model_input], dim=1)
if args.class_labels_conditioning == "timesteps":
class_labels = timesteps
else:
# this branch
class_labels = None
# Predict the noise residual
model_pred = unet(
noisy_model_input,
timesteps,
encoder_hidden_states,
class_labels=class_labels,
return_dict=False,
)[0]
# if model predicts variance, throw away the prediction. we will only train on the
# simplified training objective. This means that all schedulers using the fine tuned
# model must be configured to use one of the fixed variance variance types.
if model_pred.shape[1] == 6:
model_pred, _ = jt.chunk(model_pred, 2, dim=1)
# 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":
# 代码会进入这个分支
target = noise_scheduler.get_velocity(model_input, noise, timesteps)
else:
raise ValueError(f"Unknown prediction type {noise_scheduler.config.prediction_type}")
loss = nn.mse_loss(model_pred, target)
loss.backward()
optimizer.step()
lr_scheduler.step()
optimizer.zero_grad()
progress_bar.update(1)
global_step += 1
logs = {"loss": loss.detach().item()}
#logs = {"loss": loss.detach().item(), "lr": lr_scheduler.get_last_lr()[0]}
progress_bar.set_postfix(**logs)
if global_step >= args.max_train_steps:
break
# Save the lora layers
unet = unet.to(jt.float32)
unet_lora_state_dict = convert_state_dict_to_diffusers(get_peft_model_state_dict(unet))
text_encoder_state_dict = None
LoraLoaderMixin.save_lora_weights(
save_directory=args.output_dir,
unet_lora_layers=unet_lora_state_dict,
text_encoder_lora_layers=text_encoder_state_dict,
safe_serialization=False
)
if __name__ == "__main__":
args = parse_args()
main(args)