Merge pull request #113 from kohya-ss/textual_inversion

Add supporting for Textual inversion

gen_img_diffusers.py

@@ -470,6 +470,9 @@ class PipelineLike():
     self.scheduler = scheduler
     self.safety_checker = None
 
+    # Textual Inversion
+    self.token_replacements = {}
+
     # CLIP guidance
     self.clip_guidance_scale = clip_guidance_scale
     self.clip_image_guidance_scale = clip_image_guidance_scale
@@ -484,6 +487,19 @@ class PipelineLike():
       self.vgg16_feat_model = torchvision.models._utils.IntermediateLayerGetter(vgg16_model.features, return_layers=return_layers)
       self.vgg16_normalize = transforms.Normalize(mean=VGG16_IMAGE_MEAN, std=VGG16_IMAGE_STD)
 
+  # Textual Inversion
+  def add_token_replacement(self, target_token_id, rep_token_ids):
+    self.token_replacements[target_token_id] = rep_token_ids
+
+  def replace_token(self, tokens):
+    new_tokens = []
+    for token in tokens:
+      if token in self.token_replacements:
+        new_tokens.extend(self.token_replacements[token])
+      else:
+        new_tokens.append(token)
+    return new_tokens
+
   # region xformersとか使う部分：独自に書き換えるので関係なし
   def enable_xformers_memory_efficient_attention(self):
     r"""
@@ -1507,6 +1523,9 @@ def get_prompts_with_weights(pipe: PipelineLike, prompt: List[str], max_length:
     for word, weight in texts_and_weights:
       # tokenize and discard the starting and the ending token
       token = pipe.tokenizer(word).input_ids[1:-1]
+
+      token = pipe.replace_token(token)
+
       text_token += token
       # copy the weight by length of token
       text_weight += [weight] * len(token)
@@ -2039,6 +2058,44 @@ def main(args):
   if args.diffusers_xformers:
     pipe.enable_xformers_memory_efficient_attention()
 
+  # Textual Inversionを処理する
+  if args.textual_inversion_embeddings:
+    token_ids_embeds = []
+    for embeds_file in args.textual_inversion_embeddings:
+      if model_util.is_safetensors(embeds_file):
+        from safetensors.torch import load_file
+        data = load_file(embeds_file)
+      else:
+        data = torch.load(embeds_file, map_location="cpu")
+
+      embeds = next(iter(data.values()))
+      if type(embeds) != torch.Tensor:
+        raise ValueError(f"weight file does not contains Tensor / 重みファイルのデータがTensorではありません: {embeds_file}")
+
+      num_vectors_per_token = embeds.size()[0]
+      token_string = os.path.splitext(os.path.basename(embeds_file))[0]
+      token_strings = [token_string] + [f"{token_string}{i+1}" for i in range(num_vectors_per_token - 1)]
+
+      # add new word to tokenizer, count is num_vectors_per_token
+      num_added_tokens = tokenizer.add_tokens(token_strings)
+      assert num_added_tokens == num_vectors_per_token, f"tokenizer has same word to token string (filename). please rename the file / 指定した名前（ファイル名）のトークンが既に存在します。ファイルをリネームしてください: {embeds_file}"
+
+      token_ids = tokenizer.convert_tokens_to_ids(token_strings)
+      print(f"Textual Inversion embeddings `{token_string}` loaded. Tokens are added: {token_ids}")
+      assert min(token_ids) == token_ids[0] and token_ids[-1] == token_ids[0] + len(token_ids) - 1, f"token ids is not ordered"
+      assert len(tokenizer) - 1 == token_ids[-1], f"token ids is not end of tokenize: {len(tokenizer)}"
+
+      if num_vectors_per_token > 1:
+        pipe.add_token_replacement(token_ids[0], token_ids)
+
+      token_ids_embeds.append((token_ids, embeds))
+
+    text_encoder.resize_token_embeddings(len(tokenizer))
+    token_embeds = text_encoder.get_input_embeddings().weight.data
+    for token_ids, embeds in token_ids_embeds:
+      for token_id, embed in zip(token_ids, embeds):
+        token_embeds[token_id] = embed
+
   # promptを取得する
   if args.from_file is not None:
     print(f"reading prompts from {args.from_file}")
@@ -2157,8 +2214,8 @@ def main(args):
   os.makedirs(args.outdir, exist_ok=True)
   max_embeddings_multiples = 1 if args.max_embeddings_multiples is None else args.max_embeddings_multiples
 
-  for iter in range(args.n_iter):
-    print(f"iteration {iter+1}/{args.n_iter}")
+  for gen_iter in range(args.n_iter):
+    print(f"iteration {gen_iter+1}/{args.n_iter}")
     iter_seed = random.randint(0, 0x7fffffff)
 
     # バッチ処理の関数
@@ -2527,6 +2584,8 @@ if __name__ == '__main__':
   parser.add_argument("--network_mul", type=float, default=None, nargs='*', help='Hypernetwork multiplier / Hypernetworkの効果の倍率')
   parser.add_argument("--network_args", type=str, default=None, nargs='*',
                       help='additional argmuments for network (key=value) / ネットワークへの追加の引数')
+  parser.add_argument("--textual_inversion_embeddings", type=str, default=None, nargs='*',
+                      help='Embeddings files of Textual Inversion / Textual Inversionのembeddings')
   parser.add_argument("--clip_skip", type=int, default=None, help='layer number from bottom to use in CLIP / CLIPの後ろからn層目の出力を使う')
   parser.add_argument("--max_embeddings_multiples", type=int, default=None,
                       help='max embeding multiples, max token length is 75 * multiples / トークン長をデフォルトの何倍とするか 75*この値 がトークン長となる')

library/train_util.py

@@ -113,9 +113,14 @@ class BaseDataset(torch.utils.data.Dataset):
 
     self.image_data: dict[str, ImageInfo] = {}
 
+    self.replacements = {}
+
   def disable_token_padding(self):
     self.token_padding_disabled = True
 
+  def add_replacement(self, str_from, str_to):
+    self.replacements[str_from] = str_to
+
   def process_caption(self, caption):
     if self.shuffle_caption:
       tokens = caption.strip().split(",")
@@ -128,6 +133,17 @@ class BaseDataset(torch.utils.data.Dataset):
           random.shuffle(tokens)
           tokens = keep_tokens + tokens
       caption = ",".join(tokens).strip()
+
+    for str_from, str_to in self.replacements.items():
+      if str_from == "":
+        # replace all
+        if type(str_to) == list:
+          caption = random.choice(str_to)
+        else:
+          caption = str_to                                      
+      else:
+        caption = caption.replace(str_from, str_to)
+
     return caption
 
   def get_input_ids(self, caption):
@@ -608,7 +624,7 @@ class FineTuningDataset(BaseDataset):
       else:
         # わりといい加減だがいい方法が思いつかん
         abs_path = glob_images(train_data_dir, image_key)
-        assert len(abs_path) >= 1, f"no image / 画像がありません: {abs_path}"
+        assert len(abs_path) >= 1, f"no image / 画像がありません: {image_key}"
         abs_path = abs_path[0]
 
       caption = img_md.get('caption')
@@ -715,15 +731,17 @@ class FineTuningDataset(BaseDataset):
     return npz_file_norm, npz_file_flip
 
 
-def debug_dataset(train_dataset):
+def debug_dataset(train_dataset, show_input_ids=False):
   print(f"Total dataset length (steps) / データセットの長さ（ステップ数）: {len(train_dataset)}")
   print("Escape for exit. / Escキーで中断、終了します")
   k = 0
   for example in train_dataset:
     if example['latents'] is not None:
       print("sample has latents from npz file")
-    for j, (ik, cap, lw) in enumerate(zip(example['image_keys'], example['captions'], example['loss_weights'])):
+    for j, (ik, cap, lw, iid) in enumerate(zip(example['image_keys'], example['captions'], example['loss_weights'], example['input_ids'])):
       print(f'{ik}, size: {train_dataset.image_data[ik].image_size}, caption: "{cap}", loss weight: {lw}')
+      if show_input_ids:
+        print(f"input ids: {iid}")
       if example['images'] is not None:
         im = example['images'][j]
         im = ((im.numpy() + 1.0) * 127.5).astype(np.uint8)

train_textual_inversion.py

@@ -0,0 +1,498 @@
+import importlib
+import argparse
+import gc
+import math
+import os
+
+from tqdm import tqdm
+import torch
+from accelerate.utils import set_seed
+import diffusers
+from diffusers import DDPMScheduler
+
+import library.train_util as train_util
+from library.train_util import DreamBoothDataset, FineTuningDataset
+
+imagenet_templates_small = [
+    "a photo of a {}",
+    "a rendering of a {}",
+    "a cropped photo of the {}",
+    "the photo of a {}",
+    "a photo of a clean {}",
+    "a photo of a dirty {}",
+    "a dark photo of the {}",
+    "a photo of my {}",
+    "a photo of the cool {}",
+    "a close-up photo of a {}",
+    "a bright photo of the {}",
+    "a cropped photo of a {}",
+    "a photo of the {}",
+    "a good photo of the {}",
+    "a photo of one {}",
+    "a close-up photo of the {}",
+    "a rendition of the {}",
+    "a photo of the clean {}",
+    "a rendition of a {}",
+    "a photo of a nice {}",
+    "a good photo of a {}",
+    "a photo of the nice {}",
+    "a photo of the small {}",
+    "a photo of the weird {}",
+    "a photo of the large {}",
+    "a photo of a cool {}",
+    "a photo of a small {}",
+]
+
+imagenet_style_templates_small = [
+    "a painting in the style of {}",
+    "a rendering in the style of {}",
+    "a cropped painting in the style of {}",
+    "the painting in the style of {}",
+    "a clean painting in the style of {}",
+    "a dirty painting in the style of {}",
+    "a dark painting in the style of {}",
+    "a picture in the style of {}",
+    "a cool painting in the style of {}",
+    "a close-up painting in the style of {}",
+    "a bright painting in the style of {}",
+    "a cropped painting in the style of {}",
+    "a good painting in the style of {}",
+    "a close-up painting in the style of {}",
+    "a rendition in the style of {}",
+    "a nice painting in the style of {}",
+    "a small painting in the style of {}",
+    "a weird painting in the style of {}",
+    "a large painting in the style of {}",
+]
+
+
+def collate_fn(examples):
+  return examples[0]
+
+
+def train(args):
+  if args.output_name is None:
+    args.output_name = args.token_string
+  use_template = args.use_object_template or args.use_style_template
+
+  train_util.verify_training_args(args)
+  train_util.prepare_dataset_args(args, True)
+
+  cache_latents = args.cache_latents
+  use_dreambooth_method = args.in_json is None
+
+  if args.seed is not None:
+    set_seed(args.seed)
+
+  tokenizer = train_util.load_tokenizer(args)
+
+  # acceleratorを準備する
+  print("prepare accelerator")
+  accelerator, unwrap_model = train_util.prepare_accelerator(args)
+
+  # mixed precisionに対応した型を用意しておき適宜castする
+  weight_dtype, save_dtype = train_util.prepare_dtype(args)
+
+  # モデルを読み込む
+  text_encoder, vae, unet, _ = train_util.load_target_model(args, weight_dtype)
+
+  # Convert the init_word to token_id
+  if args.init_word is not None:
+    init_token_id = tokenizer.encode(args.init_word, add_special_tokens=False)
+    assert len(
+        init_token_id) == 1, f"init word {args.init_word} is not converted to single token / 初期化単語が二つ以上のトークンに変換されます。別の単語を使ってください"
+    init_token_id = init_token_id[0]
+  else:
+    init_token_id = None
+
+  # add new word to tokenizer, count is num_vectors_per_token
+  token_strings = [args.token_string] + [f"{args.token_string}{i+1}" for i in range(args.num_vectors_per_token - 1)]
+  num_added_tokens = tokenizer.add_tokens(token_strings)
+  assert num_added_tokens == args.num_vectors_per_token, f"tokenizer has same word to token string. please use another one / 指定したargs.token_stringは既に存在します。別の単語を使ってください: {args.token_string}"
+
+  token_ids = tokenizer.convert_tokens_to_ids(token_strings)
+  print(f"tokens are added: {token_ids}")
+  assert min(token_ids) == token_ids[0] and token_ids[-1] == token_ids[0] + len(token_ids) - 1, f"token ids is not ordered"
+  assert len(tokenizer) - 1 == token_ids[-1], f"token ids is not end of tokenize: {len(tokenizer)}"
+
+  # Resize the token embeddings as we are adding new special tokens to the tokenizer
+  text_encoder.resize_token_embeddings(len(tokenizer))
+
+  # Initialise the newly added placeholder token with the embeddings of the initializer token
+  token_embeds = text_encoder.get_input_embeddings().weight.data
+  if init_token_id is not None:
+    for token_id in token_ids:
+      token_embeds[token_id] = token_embeds[init_token_id]
+      # print(token_id, token_embeds[token_id].mean(), token_embeds[token_id].min())
+
+  # load weights
+  if args.weights is not None:
+    embeddings = load_weights(args.weights)
+    assert len(token_ids) == len(
+        embeddings), f"num_vectors_per_token is mismatch for weights / 指定した重みとnum_vectors_per_tokenの値が異なります: {len(embeddings)}"
+    # print(token_ids, embeddings.size())
+    for token_id, embedding in zip(token_ids, embeddings):
+      token_embeds[token_id] = embedding
+      # print(token_id, token_embeds[token_id].mean(), token_embeds[token_id].min())
+    print(f"weighs loaded")
+
+  print(f"create embeddings for {args.num_vectors_per_token} tokens, for {args.token_string}")
+
+  # データセットを準備する
+  if use_dreambooth_method:
+    print("Use DreamBooth method.")
+    train_dataset = DreamBoothDataset(args.train_batch_size, args.train_data_dir, args.reg_data_dir,
+                                      tokenizer, args.max_token_length, args.caption_extension, args.shuffle_caption, args.keep_tokens,
+                                      args.resolution, args.enable_bucket, args.min_bucket_reso, args.max_bucket_reso, args.prior_loss_weight,
+                                      args.flip_aug, args.color_aug, args.face_crop_aug_range, args.random_crop, args.debug_dataset)
+  else:
+    print("Train with captions.")
+    train_dataset = FineTuningDataset(args.in_json, args.train_batch_size, args.train_data_dir,
+                                      tokenizer, args.max_token_length, args.shuffle_caption, args.keep_tokens,
+                                      args.resolution, args.enable_bucket, args.min_bucket_reso, args.max_bucket_reso,
+                                      args.flip_aug, args.color_aug, args.face_crop_aug_range, args.random_crop,
+                                      args.dataset_repeats, args.debug_dataset)
+
+  # make captions: tokenstring tokenstring1 tokenstring2 ...tokenstringn という文字列に書き換える超乱暴な実装
+  if use_template:
+    print("use template for training captions. is object: {args.use_object_template}")
+    templates = imagenet_templates_small if args.use_object_template else imagenet_style_templates_small
+    replace_to = " ".join(token_strings)
+    captions = []
+    for tmpl in templates:
+      captions.append(tmpl.format(replace_to))
+    train_dataset.add_replacement("", captions)
+  elif args.num_vectors_per_token > 1:
+    replace_to = " ".join(token_strings)
+    train_dataset.add_replacement(args.token_string, replace_to)
+
+  train_dataset.make_buckets()
+
+  if args.debug_dataset:
+    train_util.debug_dataset(train_dataset, show_input_ids=True)
+    return
+  if len(train_dataset) == 0:
+    print("No data found. Please verify arguments / 画像がありません。引数指定を確認してください")
+    return
+
+  # モデルに xformers とか memory efficient attention を組み込む
+  train_util.replace_unet_modules(unet, args.mem_eff_attn, args.xformers)
+
+  # 学習を準備する
+  if cache_latents:
+    vae.to(accelerator.device, dtype=weight_dtype)
+    vae.requires_grad_(False)
+    vae.eval()
+    with torch.no_grad():
+      train_dataset.cache_latents(vae)
+    vae.to("cpu")
+    if torch.cuda.is_available():
+      torch.cuda.empty_cache()
+    gc.collect()
+
+  if args.gradient_checkpointing:
+    unet.enable_gradient_checkpointing()
+    text_encoder.gradient_checkpointing_enable()
+
+  # 学習に必要なクラスを準備する
+  print("prepare optimizer, data loader etc.")
+
+  # 8-bit Adamを使う
+  if args.use_8bit_adam:
+    try:
+      import bitsandbytes as bnb
+    except ImportError:
+      raise ImportError("No bitsand bytes / bitsandbytesがインストールされていないようです")
+    print("use 8-bit Adam optimizer")
+    optimizer_class = bnb.optim.AdamW8bit
+  else:
+    optimizer_class = torch.optim.AdamW
+
+  trainable_params = text_encoder.get_input_embeddings().parameters()
+
+  # betaやweight decayはdiffusers DreamBoothもDreamBooth SDもデフォルト値のようなのでオプションはとりあえず省略
+  optimizer = optimizer_class(trainable_params, lr=args.learning_rate)
+
+  # dataloaderを準備する
+  # DataLoaderのプロセス数：0はメインプロセスになる
+  n_workers = min(args.max_data_loader_n_workers, os.cpu_count() - 1)      # cpu_count-1 ただし最大で指定された数まで
+  train_dataloader = torch.utils.data.DataLoader(
+      train_dataset, batch_size=1, shuffle=False, collate_fn=collate_fn, num_workers=n_workers)
+
+  # 学習ステップ数を計算する
+  if args.max_train_epochs is not None:
+    args.max_train_steps = args.max_train_epochs * len(train_dataloader)
+    print(f"override steps. steps for {args.max_train_epochs} epochs is / 指定エポックまでのステップ数: {args.max_train_steps}")
+
+  # lr schedulerを用意する
+  lr_scheduler = diffusers.optimization.get_scheduler(
+      args.lr_scheduler, optimizer, num_warmup_steps=args.lr_warmup_steps, num_training_steps=args.max_train_steps * args.gradient_accumulation_steps)
+
+  # acceleratorがなんかよろしくやってくれるらしい
+  text_encoder, optimizer, train_dataloader, lr_scheduler = accelerator.prepare(
+      text_encoder, optimizer, train_dataloader, lr_scheduler)
+
+  index_no_updates = torch.arange(len(tokenizer)) < token_ids[0]
+  print(len(index_no_updates), torch.sum(index_no_updates))
+  orig_embeds_params = unwrap_model(text_encoder).get_input_embeddings().weight.data.detach().clone()
+
+  # Freeze all parameters except for the token embeddings in text encoder
+  text_encoder.requires_grad_(True)
+  text_encoder.text_model.encoder.requires_grad_(False)
+  text_encoder.text_model.final_layer_norm.requires_grad_(False)
+  text_encoder.text_model.embeddings.position_embedding.requires_grad_(False)
+  # text_encoder.text_model.embeddings.token_embedding.requires_grad_(True)
+
+  unet.requires_grad_(False)
+  unet.to(accelerator.device, dtype=weight_dtype)
+  if args.gradient_checkpointing:                       # according to TI example in Diffusers, train is required
+    unet.train()
+  else:
+    unet.eval()
+
+  if not cache_latents:
+    vae.requires_grad_(False)
+    vae.eval()
+    vae.to(accelerator.device, dtype=weight_dtype)
+
+  # 実験的機能：勾配も含めたfp16学習を行う　PyTorchにパッチを当ててfp16でのgrad scaleを有効にする
+  if args.full_fp16:
+    train_util.patch_accelerator_for_fp16_training(accelerator)
+    text_encoder.to(weight_dtype)
+
+  # resumeする
+  if args.resume is not None:
+    print(f"resume training from state: {args.resume}")
+    accelerator.load_state(args.resume)
+
+  # epoch数を計算する
+  num_update_steps_per_epoch = math.ceil(len(train_dataloader) / args.gradient_accumulation_steps)
+  num_train_epochs = math.ceil(args.max_train_steps / num_update_steps_per_epoch)
+  if (args.save_n_epoch_ratio is not None) and (args.save_n_epoch_ratio > 0):
+    args.save_every_n_epochs = math.floor(num_train_epochs / args.save_n_epoch_ratio) or 1
+
+  # 学習する
+  total_batch_size = args.train_batch_size * accelerator.num_processes * args.gradient_accumulation_steps
+  print("running training / 学習開始")
+  print(f"  num train images * repeats / 学習画像の数×繰り返し回数: {train_dataset.num_train_images}")
+  print(f"  num reg images / 正則化画像の数: {train_dataset.num_reg_images}")
+  print(f"  num batches per epoch / 1epochのバッチ数: {len(train_dataloader)}")
+  print(f"  num epochs / epoch数: {num_train_epochs}")
+  print(f"  batch size per device / バッチサイズ: {args.train_batch_size}")
+  print(f"  total train batch size (with parallel & distributed & accumulation) / 総バッチサイズ（並列学習、勾配合計含む）: {total_batch_size}")
+  print(f"  gradient ccumulation steps / 勾配を合計するステップ数 = {args.gradient_accumulation_steps}")
+  print(f"  total optimization steps / 学習ステップ数: {args.max_train_steps}")
+
+  progress_bar = tqdm(range(args.max_train_steps), smoothing=0, disable=not accelerator.is_local_main_process, desc="steps")
+  global_step = 0
+
+  noise_scheduler = DDPMScheduler(beta_start=0.00085, beta_end=0.012, beta_schedule="scaled_linear",
+                                  num_train_timesteps=1000, clip_sample=False)
+
+  if accelerator.is_main_process:
+    accelerator.init_trackers("textual_inversion")
+
+  for epoch in range(num_train_epochs):
+    print(f"epoch {epoch+1}/{num_train_epochs}")
+
+    text_encoder.train()
+
+    loss_total = 0
+    bef_epo_embs = unwrap_model(text_encoder).get_input_embeddings().weight[token_ids].data.detach().clone()
+    for step, batch in enumerate(train_dataloader):
+      with accelerator.accumulate(text_encoder):
+        with torch.no_grad():
+          if "latents" in batch and batch["latents"] is not None:
+            latents = batch["latents"].to(accelerator.device)
+          else:
+            # latentに変換
+            latents = vae.encode(batch["images"].to(dtype=weight_dtype)).latent_dist.sample()
+          latents = latents * 0.18215
+        b_size = latents.shape[0]
+
+        # Get the text embedding for conditioning
+        input_ids = batch["input_ids"].to(accelerator.device)
+        encoder_hidden_states = train_util.get_hidden_states(args, input_ids, tokenizer, text_encoder, torch.float) # weight_dtype) use float instead of fp16/bf16 because text encoder is float
+
+        # Sample noise that we'll add to the latents
+        noise = torch.randn_like(latents, device=latents.device)
+
+        # Sample a random timestep for each image
+        timesteps = torch.randint(0, noise_scheduler.config.num_train_timesteps, (b_size,), 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)
+
+        # Predict the noise residual
+        noise_pred = unet(noisy_latents, timesteps, encoder_hidden_states).sample
+
+        if args.v_parameterization:
+          # v-parameterization training
+          target = noise_scheduler.get_velocity(latents, noise, timesteps)
+        else:
+          target = noise
+
+        loss = torch.nn.functional.mse_loss(noise_pred.float(), target.float(), reduction="none")
+        loss = loss.mean([1, 2, 3])
+
+        loss_weights = batch["loss_weights"]                      # 各sampleごとのweight
+        loss = loss * loss_weights
+
+        loss = loss.mean()                # 平均なのでbatch_sizeで割る必要なし
+
+        accelerator.backward(loss)
+        if accelerator.sync_gradients:
+          params_to_clip = text_encoder.get_input_embeddings().parameters()
+          accelerator.clip_grad_norm_(params_to_clip, 1.0)  # args.max_grad_norm)
+
+        optimizer.step()
+        lr_scheduler.step()
+        optimizer.zero_grad(set_to_none=True)
+
+        # Let's make sure we don't update any embedding weights besides the newly added token
+        with torch.no_grad():
+          unwrap_model(text_encoder).get_input_embeddings().weight[index_no_updates] = orig_embeds_params[index_no_updates]
+
+      # Checks if the accelerator has performed an optimization step behind the scenes
+      if accelerator.sync_gradients:
+        progress_bar.update(1)
+        global_step += 1
+
+      current_loss = loss.detach().item()
+      if args.logging_dir is not None:
+        logs = {"loss": current_loss, "lr": lr_scheduler.get_last_lr()[0]}
+        accelerator.log(logs, step=global_step)
+
+      loss_total += current_loss
+      avr_loss = loss_total / (step+1)
+      logs = {"loss": avr_loss}  # , "lr": lr_scheduler.get_last_lr()[0]}
+      progress_bar.set_postfix(**logs)
+
+      if global_step >= args.max_train_steps:
+        break
+
+    if args.logging_dir is not None:
+      logs = {"loss/epoch": loss_total / len(train_dataloader)}
+      accelerator.log(logs, step=epoch+1)
+
+    accelerator.wait_for_everyone()
+
+    updated_embs = unwrap_model(text_encoder).get_input_embeddings().weight[token_ids].data.detach().clone()
+    d = updated_embs - bef_epo_embs
+    print(bef_epo_embs.size(), updated_embs.size(), d.mean(), d.min())
+
+    if args.save_every_n_epochs is not None:
+      model_name = train_util.DEFAULT_EPOCH_NAME if args.output_name is None else args.output_name
+
+      def save_func():
+        ckpt_name = train_util.EPOCH_FILE_NAME.format(model_name, epoch + 1) + '.' + args.save_model_as
+        ckpt_file = os.path.join(args.output_dir, ckpt_name)
+        print(f"saving checkpoint: {ckpt_file}")
+        save_weights(ckpt_file, updated_embs, save_dtype)
+
+      def remove_old_func(old_epoch_no):
+        old_ckpt_name = train_util.EPOCH_FILE_NAME.format(model_name, old_epoch_no) + '.' + args.save_model_as
+        old_ckpt_file = os.path.join(args.output_dir, old_ckpt_name)
+        if os.path.exists(old_ckpt_file):
+          print(f"removing old checkpoint: {old_ckpt_file}")
+          os.remove(old_ckpt_file)
+
+      saving = train_util.save_on_epoch_end(args, save_func, remove_old_func, epoch + 1, num_train_epochs)
+      if saving and args.save_state:
+        train_util.save_state_on_epoch_end(args, accelerator, model_name, epoch + 1)
+
+    # end of epoch
+
+  is_main_process = accelerator.is_main_process
+  if is_main_process:
+    text_encoder = unwrap_model(text_encoder)
+
+  accelerator.end_training()
+
+  if args.save_state:
+    train_util.save_state_on_train_end(args, accelerator)
+
+  updated_embs = text_encoder.get_input_embeddings().weight[token_ids].data.detach().clone()
+
+  del accelerator                         # この後メモリを使うのでこれは消す
+
+  if is_main_process:
+    os.makedirs(args.output_dir, exist_ok=True)
+
+    model_name = train_util.DEFAULT_LAST_OUTPUT_NAME if args.output_name is None else args.output_name
+    ckpt_name = model_name + '.' + args.save_model_as
+    ckpt_file = os.path.join(args.output_dir, ckpt_name)
+
+    print(f"save trained model to {ckpt_file}")
+    save_weights(ckpt_file, updated_embs, save_dtype)
+    print("model saved.")
+
+
+def save_weights(file, updated_embs, save_dtype):
+  state_dict = {"emb_params": updated_embs}
+
+  if save_dtype is not None:
+    for key in list(state_dict.keys()):
+      v = state_dict[key]
+      v = v.detach().clone().to("cpu").to(save_dtype)
+      state_dict[key] = v
+
+  if os.path.splitext(file)[1] == '.safetensors':
+    from safetensors.torch import save_file
+    save_file(state_dict, file)
+  else:
+    torch.save(state_dict, file)                    # can be loaded in Web UI
+
+
+def load_weights(file):
+  if os.path.splitext(file)[1] == '.safetensors':
+    from safetensors.torch import load_file
+    data = load_file(file)
+  else:
+    # compatible to Web UI's file format
+    data = torch.load(file, map_location='cpu')
+    if type(data) != dict:
+      raise ValueError(f"weight file is not dict / 重みファイルがdict形式ではありません: {file}")
+
+    if 'string_to_param' in data:                           # textual inversion embeddings
+      data = data['string_to_param']
+      if hasattr(data, '_parameters'):                      # support old PyTorch?
+        data = getattr(data, '_parameters')
+
+  emb = next(iter(data.values()))
+  if type(emb) != torch.Tensor:
+    raise ValueError(f"weight file does not contains Tensor / 重みファイルのデータがTensorではありません: {file}")
+
+  if len(emb.size()) == 1:
+    emb = emb.unsqueeze(0)
+
+  return emb
+
+
+if __name__ == '__main__':
+  parser = argparse.ArgumentParser()
+
+  train_util.add_sd_models_arguments(parser)
+  train_util.add_dataset_arguments(parser, True, True)
+  train_util.add_training_arguments(parser, True)
+
+  parser.add_argument("--save_model_as", type=str, default="pt", choices=[None, "ckpt", "pt", "safetensors"],
+                      help="format to save the model (default is .pt) / モデル保存時の形式（デフォルトはpt）")
+
+  parser.add_argument("--weights", type=str, default=None,
+                      help="embedding weights to initialize / 学習するネットワークの初期重み")
+  parser.add_argument("--num_vectors_per_token", type=int, default=1,
+                      help='number of vectors per token / トークンに割り当てるembeddingsの要素数')
+  parser.add_argument("--token_string", type=str, default=None,
+                      help="token string used in training, must not exist in tokenizer / 学習時に使用されるトークン文字列、tokenizerに存在しない文字であること")
+  parser.add_argument("--init_word", type=str, default=None,
+                      help="word to initialize vector / ベクトルを初期化に使用する単語、tokenizerで一語になること")
+  parser.add_argument("--use_object_template", action='store_true',
+                      help="ignore caption and use default templates for object / キャプションは使わずデフォルトの物体用テンプレートで学習する")
+  parser.add_argument("--use_style_template", action='store_true',
+                      help="ignore caption and use default templates for stype / キャプションは使わずデフォルトのスタイル用テンプレートで学習する")
+
+  args = parser.parse_args()
+  train(args)