WIP creating textual inversion training script

extensions_built_in/textual_inversion_trainer/TextualInversionTrainer.py

@@ -0,0 +1,179 @@
+import copy
+import random
+from collections import OrderedDict
+import os
+from contextlib import nullcontext
+from typing import Optional, Union, List
+from torch.utils.data import ConcatDataset, DataLoader
+
+from toolkit.config_modules import ReferenceDatasetConfig
+from toolkit.data_loader import PairedImageDataset, ImageDataset
+from toolkit.prompt_utils import concat_prompt_embeds, split_prompt_embeds
+from toolkit.stable_diffusion_model import StableDiffusion, PromptEmbeds
+from toolkit.train_tools import get_torch_dtype, apply_snr_weight, apply_noise_offset
+import gc
+from toolkit import train_tools
+import torch
+from jobs.process import BaseSDTrainProcess
+import random
+from toolkit.basic import value_map
+
+
+def flush():
+    torch.cuda.empty_cache()
+    gc.collect()
+
+
+class TextualInversionTrainer(BaseSDTrainProcess):
+    sd: StableDiffusion
+    data_loader: DataLoader = None
+
+    def __init__(self, process_id: int, job, config: OrderedDict, **kwargs):
+        super().__init__(process_id, job, config, **kwargs)
+        pass
+
+    def before_model_load(self):
+        pass
+
+    def hook_before_train_loop(self):
+        self.sd.vae.eval()
+        self.sd.vae.to(self.device_torch)
+
+        # keep original embeddings as reference
+        self.orig_embeds_params = self.sd.text_encoder.get_input_embeddings().weight.data.clone()
+        # set text encoder to train. Not sure if this is necessary but diffusers example did it
+        self.sd.text_encoder.train()
+        pass
+
+    def hook_train_loop(self, batch):
+        with torch.no_grad():
+            imgs, prompts = batch
+
+            # very loosely based on this. very loosely
+            # ref https://github.com/huggingface/diffusers/blob/main/examples/textual_inversion/textual_inversion.py
+
+            conditioned_prompts = []
+
+            for prompt in prompts:
+                # replace our name with the embedding
+                if self.embed_config.trigger in prompt:
+                    # if the trigger is a part of the prompt, replace it with the token ids
+                    prompt = prompt.replace(self.embed_config.trigger, self.embedding.get_embedding_string())
+                if self.name in prompt:
+                    # if the name is in the prompt, replace it with the trigger
+                    prompt = prompt.replace(self.name, self.embedding.get_embedding_string())
+                if "[name]" in prompt:
+                    # in [name] in prompt, replace it with the trigger
+                    prompt = prompt.replace("[name]", self.embedding.get_embedding_string())
+                if self.embedding.get_embedding_string() not in prompt:
+                    # add it to the beginning of the prompt
+                    prompt = self.embedding.get_embedding_string() + " " + prompt
+
+                conditioned_prompts.append(prompt)
+
+            # # get embedding ids
+            # embedding_ids_list = [self.sd.tokenizer(
+            #     text,
+            #     padding="max_length",
+            #     truncation=True,
+            #     max_length=self.sd.tokenizer.model_max_length,
+            #     return_tensors="pt",
+            # ).input_ids[0] for text in conditioned_prompts]
+
+            # hidden_states = []
+            # for embedding_ids, img in zip(embedding_ids_list, imgs):
+            #     hidden_state = {
+            #         "input_ids": embedding_ids,
+            #         "pixel_values": img
+            #     }
+            #     hidden_states.append(hidden_state)
+
+            dtype = get_torch_dtype(self.train_config.dtype)
+            imgs = imgs.to(self.device_torch, dtype=dtype)
+            latents = self.sd.encode_images(imgs)
+
+            noise_scheduler = self.sd.noise_scheduler
+            optimizer = self.optimizer
+            lr_scheduler = self.lr_scheduler
+
+            self.sd.noise_scheduler.set_timesteps(
+                self.train_config.max_denoising_steps, device=self.device_torch
+            )
+
+            timesteps = torch.randint(0, self.train_config.max_denoising_steps, (1,), device=self.device_torch)
+            timesteps = timesteps.long()
+
+            # get noise
+            noise = self.sd.get_latent_noise(
+                pixel_height=imgs.shape[2],
+                pixel_width=imgs.shape[3],
+                batch_size=self.train_config.batch_size,
+                noise_offset=self.train_config.noise_offset
+            ).to(self.device_torch, dtype=dtype)
+
+            noisy_latents = noise_scheduler.add_noise(latents, noise, timesteps)
+
+            # remove grads for these
+            noisy_latents.requires_grad = False
+            noise.requires_grad = False
+
+        flush()
+
+        self.optimizer.zero_grad()
+        noisy_latents.requires_grad = False
+
+        # text encoding
+        embedding_list = []
+        # embed the prompts
+        for prompt in conditioned_prompts:
+            embedding = self.sd.encode_prompt(prompt).to(self.device_torch, dtype=dtype)
+            embedding_list.append(embedding)
+        conditional_embeds = concat_prompt_embeds(embedding_list)
+
+        noise_pred = self.sd.predict_noise(
+            latents=noisy_latents.to(self.device_torch, dtype=dtype),
+            conditional_embeddings=conditional_embeds.to(self.device_torch, dtype=dtype),
+            timestep=timesteps,
+            guidance_scale=1.0,
+        )
+        noise = noise.to(self.device_torch, dtype=dtype)
+
+        if self.sd.prediction_type == 'v_prediction':
+            # v-parameterization training
+            target = noise_scheduler.get_velocity(noisy_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])
+
+        if self.train_config.min_snr_gamma is not None and self.train_config.min_snr_gamma > 0.000001:
+            # add min_snr_gamma
+            loss = apply_snr_weight(loss, timesteps, noise_scheduler, self.train_config.min_snr_gamma)
+
+        loss = loss.mean()
+
+        # back propagate loss to free ram
+        loss.backward()
+        flush()
+
+        # apply gradients
+        optimizer.step()
+        optimizer.zero_grad()
+        lr_scheduler.step()
+
+        # Let's make sure we don't update any embedding weights besides the newly added token
+        index_no_updates = torch.ones((len(self.sd.tokenizer),), dtype=torch.bool)
+        index_no_updates[
+        min(self.embedding.placeholder_token_ids): max(self.embedding.placeholder_token_ids) + 1] = False
+        with torch.no_grad():
+            self.sd.text_encoder.get_input_embeddings().weight[
+                index_no_updates
+            ] = self.orig_embeds_params[index_no_updates]
+
+        loss_dict = OrderedDict(
+            {'loss': loss.item()}
+        )
+
+        return loss_dict
+        # end hook_train_loop

extensions_built_in/textual_inversion_trainer/__init__.py

@@ -0,0 +1,25 @@
+# This is an example extension for custom training. It is great for experimenting with new ideas.
+from toolkit.extension import Extension
+
+
+# We make a subclass of Extension
+class OffsetSliderTrainer(Extension):
+    # uid must be unique, it is how the extension is identified
+    uid = "textual_inversion_trainer"
+
+    # name is the name of the extension for printing
+    name = "Textual Inversion Trainer"
+
+    # This is where your process class is loaded
+    # keep your imports in here so they don't slow down the rest of the program
+    @classmethod
+    def get_process(cls):
+        # import your process class here so it is only loaded when needed and return it
+        from .TextualInversionTrainer import TextualInversionTrainer
+        return TextualInversionTrainer
+
+
+AI_TOOLKIT_EXTENSIONS = [
+    # you can put a list of extensions here
+    OffsetSliderTrainer
+]

extensions_built_in/textual_inversion_trainer/config/train.example.yaml

@@ -0,0 +1,107 @@
+---
+job: extension
+config:
+  name: example_name
+  process:
+    - type: 'image_reference_slider_trainer'
+      training_folder: "/mnt/Train/out/LoRA"
+      device: cuda:0
+      # for tensorboard logging
+      log_dir: "/home/jaret/Dev/.tensorboard"
+      network:
+        type: "lora"
+        linear: 8
+        linear_alpha: 8
+      train:
+        noise_scheduler: "ddpm" # or "ddpm", "lms", "euler_a"
+        steps: 5000
+        lr: 1e-4
+        train_unet: true
+        gradient_checkpointing: true
+        train_text_encoder: true
+        optimizer: "adamw"
+        optimizer_params:
+          weight_decay: 1e-2
+        lr_scheduler: "constant"
+        max_denoising_steps: 1000
+        batch_size: 1
+        dtype: bf16
+        xformers: true
+        skip_first_sample: true
+        noise_offset: 0.0
+      model:
+        name_or_path: "/path/to/model.safetensors"
+        is_v2: false  # for v2 models
+        is_xl: false  # for SDXL models
+        is_v_pred: false # for v-prediction models (most v2 models)
+      save:
+        dtype: float16 # precision to save
+        save_every: 1000 # save every this many steps
+        max_step_saves_to_keep: 2 # only affects step counts
+      sample:
+        sampler: "ddpm" # must match train.noise_scheduler
+        sample_every: 100 # sample every this many steps
+        width: 512
+        height: 512
+        prompts:
+          - "photo of a woman with red hair taking a selfie --m -3"
+          - "photo of a woman with red hair taking a selfie --m -1"
+          - "photo of a woman with red hair taking a selfie --m 1"
+          - "photo of a woman with red hair taking a selfie --m 3"
+          - "close up photo of a man smiling at the camera, in a tank top --m -3"
+          - "close up photo of a man smiling at the camera, in a tank top--m -1"
+          - "close up photo of a man smiling at the camera, in a tank top --m 1"
+          - "close up photo of a man smiling at the camera, in a tank top --m 3"
+          - "photo of a blonde woman smiling, barista --m -3"
+          - "photo of a blonde woman smiling, barista --m -1"
+          - "photo of a blonde woman smiling, barista --m 1"
+          - "photo of a blonde woman smiling, barista --m 3"
+          - "photo of a Christina Hendricks --m -1"
+          - "photo of a Christina Hendricks --m -1"
+          - "photo of a Christina Hendricks --m 1"
+          - "photo of a Christina Hendricks --m 3"
+          - "photo of a Christina Ricci --m -3"
+          - "photo of a Christina Ricci --m -1"
+          - "photo of a Christina Ricci --m 1"
+          - "photo of a Christina Ricci --m 3"
+        neg: "cartoon, fake, drawing, illustration, cgi, animated, anime"
+        seed: 42
+        walk_seed: false
+        guidance_scale: 7
+        sample_steps: 20
+        network_multiplier: 1.0
+
+      logging:
+        log_every: 10 # log every this many steps
+        use_wandb: false # not supported yet
+        verbose: false
+
+      slider:
+        datasets:
+          - pair_folder: "/path/to/folder/side/by/side/images"
+            network_weight: 2.0
+            target_class: "" # only used as default if caption txt are not present
+            size: 512
+          - pair_folder: "/path/to/folder/side/by/side/images"
+            network_weight: 4.0
+            target_class: "" # only used as default if caption txt are not present
+            size: 512
+
+
+# you can put any information you want here, and it will be saved in the model
+# the below is an example. I recommend doing trigger words at a minimum
+# in the metadata. The software will include this plus some other information
+meta:
+  name: "[name]"  # [name] gets replaced with the name above
+  description: A short description of your model
+  trigger_words:
+  - put
+  - trigger
+  - words
+  - here
+  version: '0.1'
+  creator:
+    name: Your Name
+    email: your@email.com
+    website: https://yourwebsite.com
+  any: All meta data above is arbitrary, it can be whatever you want.

jobs/process/BaseSDTrainProcess.py

@@ -5,6 +5,8 @@ from typing import Union
 
 from torch.utils.data import DataLoader
 
+from toolkit.data_loader import get_dataloader_from_datasets
+from toolkit.embedding import Embedding
 from toolkit.lora_special import LoRASpecialNetwork
 from toolkit.optimizer import get_optimizer
 
@@ -20,7 +22,7 @@ import torch
 from tqdm import tqdm
 
 from toolkit.config_modules import SaveConfig, LogingConfig, SampleConfig, NetworkConfig, TrainConfig, ModelConfig, \
-    GenerateImageConfig
+    GenerateImageConfig, EmbeddingConfig, DatasetConfig
 
 
 def flush():
@@ -30,6 +32,7 @@ def flush():
 
 class BaseSDTrainProcess(BaseTrainProcess):
     sd: StableDiffusion
+    embedding: Union[Embedding, None] = None
 
     def __init__(self, process_id: int, job, config: OrderedDict, custom_pipeline=None):
         super().__init__(process_id, job, config)
@@ -59,6 +62,16 @@ class BaseSDTrainProcess(BaseTrainProcess):
         self.lr_scheduler = None
         self.data_loader: Union[DataLoader, None] = None
 
+        raw_datasets = self.get_conf('datasets', None)
+        self.datasets = None
+        if raw_datasets is not None and len(raw_datasets) > 0:
+            self.datasets = [DatasetConfig(**d) for d in raw_datasets]
+
+        self.embed_config = None
+        embedding_raw = self.get_conf('embedding', None)
+        if embedding_raw is not None:
+            self.embed_config = EmbeddingConfig(**embedding_raw)
+
         self.sd = StableDiffusion(
             device=self.device,
             model_config=self.model_config,
@@ -68,6 +81,7 @@ class BaseSDTrainProcess(BaseTrainProcess):
 
         # to hold network if there is one
         self.network = None
+        self.embedding = None
 
     def sample(self, step=None, is_first=False):
         sample_folder = os.path.join(self.save_root, 'samples')
@@ -89,8 +103,26 @@ class BaseSDTrainProcess(BaseTrainProcess):
 
             output_path = os.path.join(sample_folder, filename)
 
+            prompt = sample_config.prompts[i]
+
+            # add embedding if there is one
+            if self.embedding is not None:
+                # replace our name with the embedding
+                if self.embed_config.trigger in prompt:
+                    # if the trigger is a part of the prompt, replace it with the token ids
+                    prompt = prompt.replace(self.embed_config.trigger, self.embedding.get_embedding_string())
+                if self.name in prompt:
+                    # if the name is in the prompt, replace it with the trigger
+                    prompt = prompt.replace(self.name, self.embedding.get_embedding_string())
+                if "[name]" in prompt:
+                    # in [name] in prompt, replace it with the trigger
+                    prompt = prompt.replace("[name]", self.embedding.get_embedding_string())
+                if self.embedding.get_embedding_string() not in prompt:
+                    # add it to the beginning of the prompt
+                    prompt = self.embedding.get_embedding_string() + " " + prompt
+
             gen_img_config_list.append(GenerateImageConfig(
-                prompt=sample_config.prompts[i],  # it will autoparse the prompt
+                prompt=prompt,  # it will autoparse the prompt
                 width=sample_config.width,
                 height=sample_config.height,
                 negative_prompt=sample_config.neg,
@@ -175,6 +207,8 @@ class BaseSDTrainProcess(BaseTrainProcess):
                 metadata=save_meta
             )
             self.network.multiplier = prev_multiplier
+        elif self.embedding is not None:
+            self.embedding.save(file_path)
         else:
             self.sd.save(
                 file_path,
@@ -197,6 +231,9 @@ class BaseSDTrainProcess(BaseTrainProcess):
     def hook_before_train_loop(self):
         pass
 
+    def before_dataset_load(self):
+        pass
+
     def hook_train_loop(self, batch=None):
         # return loss
         return 0.0
@@ -208,6 +245,11 @@ class BaseSDTrainProcess(BaseTrainProcess):
             # pattern is {job_name}_{zero_filles_step}.safetensors or {job_name}.safetensors
             pattern = f"{self.job.name}*.safetensors"
             files = glob.glob(os.path.join(self.save_root, pattern))
+            if len(files) > 0:
+                latest_file = max(files, key=os.path.getctime)
+            # try pt
+            pattern = f"{self.job.name}*.pt"
+            files = glob.glob(os.path.join(self.save_root, pattern))
             if len(files) > 0:
                 latest_file = max(files, key=os.path.getctime)
             return latest_file
@@ -230,11 +272,21 @@ class BaseSDTrainProcess(BaseTrainProcess):
     def run(self):
         # run base process run
         BaseTrainProcess.run(self)
+        ### HOOk ###
+        self.before_dataset_load()
+        # load datasets if passed in the root process
+        if self.datasets is not None:
+            self.data_loader = get_dataloader_from_datasets(self.datasets, self.train_config.batch_size)
+
         ### HOOK ###
         self.hook_before_model_load()
         # run base sd process run
         self.sd.load_model()
 
+        if self.train_config.gradient_checkpointing:
+            # may get disabled elsewhere
+            self.sd.unet.enable_gradient_checkpointing()
+
         dtype = get_torch_dtype(self.train_config.dtype)
 
         # model is loaded from BaseSDProcess
@@ -303,7 +355,18 @@ class BaseSDTrainProcess(BaseTrainProcess):
                 self.print(f"Loading from {latest_save_path}")
                 self.load_weights(latest_save_path)
                 self.network.multiplier = 1.0
+        elif self.embed_config is not None:
+            self.embedding = Embedding(
+                sd=self.sd,
+                embed_config=self.embed_config
+            )
+            latest_save_path = self.get_latest_save_path()
+            # load last saved weights
+            if latest_save_path is not None:
+                self.embedding.load_embedding_from_file(latest_save_path, self.device_torch)
 
+            # set trainable params
+            params = self.embedding.get_trainable_params()
 
         else:
             params = []

toolkit/config_modules.py

@@ -1,6 +1,6 @@
 import os
 import time
-from typing import List, Optional
+from typing import List, Optional, Literal
 import random
 
 
@@ -50,6 +50,13 @@ class NetworkConfig:
         self.conv_alpha: float = kwargs.get('conv_alpha', self.conv)
 
 
+class EmbeddingConfig:
+    def __init__(self, **kwargs):
+        self.trigger = kwargs.get('trigger', 'custom_embedding')
+        self.tokens = kwargs.get('tokens', 4)
+        self.init_words = kwargs.get('init_phrase', '*')
+        self.save_format = kwargs.get('save_format', 'safetensors')
+
 class TrainConfig:
     def __init__(self, **kwargs):
         self.noise_scheduler = kwargs.get('noise_scheduler', 'ddpm')
@@ -146,6 +153,20 @@ class SliderConfig:
                 self.targets.append(target)
 
 
+class DatasetConfig:
+    caption_type: Literal["txt", "caption"] = 'txt'
+
+    def __init__(self, **kwargs):
+        self.type = kwargs.get('type', 'image')  # sd, slider, reference
+        self.folder_path: str = kwargs.get('folder_path', None)
+        self.default_caption: str = kwargs.get('default_caption', None)
+        self.caption_type: str = kwargs.get('caption_type', None)
+        self.random_scale: bool = kwargs.get('random_scale', False)
+        self.random_crop: bool = kwargs.get('random_crop', False)
+        self.resolution: int = kwargs.get('resolution', 512)
+        self.scale: float = kwargs.get('scale', 1.0)
+
+
 class GenerateImageConfig:
     def __init__(
             self,

toolkit/data_loader.py

@@ -1,23 +1,33 @@
 import os
 import random
+from typing import List
 
 import cv2
 import numpy as np
 from PIL import Image
 from PIL.ImageOps import exif_transpose
 from torchvision import transforms
-from torch.utils.data import Dataset
+from torch.utils.data import Dataset, DataLoader, ConcatDataset
 from tqdm import tqdm
 import albumentations as A
 
+from toolkit.config_modules import DatasetConfig
+from toolkit.dataloader_mixins import CaptionMixin
 
-class ImageDataset(Dataset):
+
+class ImageDataset(Dataset, CaptionMixin):
     def __init__(self, config):
         self.config = config
         self.name = self.get_config('name', 'dataset')
         self.path = self.get_config('path', required=True)
         self.scale = self.get_config('scale', 1)
         self.random_scale = self.get_config('random_scale', False)
+        self.include_prompt = self.get_config('include_prompt', False)
+        self.default_prompt = self.get_config('default_prompt', '')
+        if self.include_prompt:
+            self.caption_type = self.get_config('caption_type', 'txt')
+        else:
+            self.caption_type = None
         # we always random crop if random scale is enabled
         self.random_crop = self.random_scale if self.random_scale else self.get_config('random_crop', False)
 
@@ -81,7 +91,11 @@ class ImageDataset(Dataset):
 
         img = self.transform(img)
 
-        return img
+        if self.include_prompt:
+            prompt = self.get_caption_item(index)
+            return img, prompt
+        else:
+            return img
 
 
 class Augments:
@@ -268,3 +282,101 @@ class PairedImageDataset(Dataset):
         img = self.transform(img)
 
         return img, prompt, (self.neg_weight, self.pos_weight)
+
+
+class AiToolkitDataset(Dataset, CaptionMixin):
+    def __init__(self, dataset_config: 'DatasetConfig'):
+        self.dataset_config = dataset_config
+        self.folder_path = dataset_config.folder_path
+        self.caption_type = dataset_config.caption_type
+        self.default_caption = dataset_config.default_caption
+        self.random_scale = dataset_config.random_scale
+        self.scale = dataset_config.scale
+        # we always random crop if random scale is enabled
+        self.random_crop = self.random_scale if self.random_scale else dataset_config.random_crop
+        self.resolution = dataset_config.resolution
+
+        # get the file list
+        self.file_list = [
+            os.path.join(self.folder_path, file) for file in os.listdir(self.folder_path) if
+            file.lower().endswith(('.jpg', '.jpeg', '.png', '.webp'))
+        ]
+
+        # this might take a while
+        print(f"  -  Preprocessing image dimensions")
+        new_file_list = []
+        bad_count = 0
+        for file in tqdm(self.file_list):
+            img = Image.open(file)
+            if int(min(img.size) * self.scale) >= self.resolution:
+                new_file_list.append(file)
+            else:
+                bad_count += 1
+
+        print(f"  -  Found {len(self.file_list)} images")
+        print(f"  -  Found {bad_count} images that are too small")
+        assert len(self.file_list) > 0, f"no images found in {self.folder_path}"
+
+        self.transform = transforms.Compose([
+            transforms.ToTensor(),
+            transforms.Normalize([0.5], [0.5]),  # normalize to [-1, 1]
+        ])
+
+    def __len__(self):
+        return len(self.file_list)
+
+    def __getitem__(self, index):
+        img_path = self.file_list[index]
+        img = exif_transpose(Image.open(img_path)).convert('RGB')
+
+        # Downscale the source image first
+        img = img.resize((int(img.size[0] * self.scale), int(img.size[1] * self.scale)), Image.BICUBIC)
+        min_img_size = min(img.size)
+
+        if self.random_crop:
+            if self.random_scale and min_img_size > self.resolution:
+                if min_img_size < self.resolution:
+                    print(
+                        f"Unexpected values: min_img_size={min_img_size}, self.resolution={self.resolution}, image file={img_path}")
+                    scale_size = self.resolution
+                else:
+                    scale_size = random.randint(self.resolution, int(min_img_size))
+                img = img.resize((scale_size, scale_size), Image.BICUBIC)
+            img = transforms.RandomCrop(self.resolution)(img)
+        else:
+            img = transforms.CenterCrop(min_img_size)(img)
+            img = img.resize((self.resolution, self.resolution), Image.BICUBIC)
+
+        img = self.transform(img)
+
+        if self.caption_type is not None:
+            prompt = self.get_caption_item(index)
+            return img, prompt
+        else:
+            return img
+
+
+def get_dataloader_from_datasets(dataset_options, batch_size=1):
+    if dataset_options is None or len(dataset_options) == 0:
+        return None
+
+    datasets = []
+    for dataset_option in dataset_options:
+        if isinstance(dataset_option, DatasetConfig):
+            config = dataset_option
+        else:
+            config = DatasetConfig(**dataset_option)
+        if config.type == 'image':
+            dataset = AiToolkitDataset(config)
+            datasets.append(dataset)
+        else:
+            raise ValueError(f"invalid dataset type: {config.type}")
+
+    concatenated_dataset = ConcatDataset(datasets)
+    data_loader = DataLoader(
+        concatenated_dataset,
+        batch_size=batch_size,
+        shuffle=True,
+        num_workers=2
+    )
+    return data_loader

toolkit/dataloader_mixins.py

@@ -0,0 +1,43 @@
+import os
+
+
+class CaptionMixin:
+    def get_caption_item(self, index):
+        if not hasattr(self, 'caption_type'):
+            raise Exception('caption_type not found on class instance')
+        if not hasattr(self, 'file_list'):
+            raise Exception('file_list not found on class instance')
+        img_path_or_tuple = self.file_list[index]
+        if isinstance(img_path_or_tuple, tuple):
+            # check if either has a prompt file
+            path_no_ext = os.path.splitext(img_path_or_tuple[0])[0]
+            prompt_path = path_no_ext + '.txt'
+            if not os.path.exists(prompt_path):
+                path_no_ext = os.path.splitext(img_path_or_tuple[1])[0]
+                prompt_path = path_no_ext + '.txt'
+        else:
+            img_path = img_path_or_tuple
+            # see if prompt file exists
+            path_no_ext = os.path.splitext(img_path)[0]
+            prompt_path = path_no_ext + '.txt'
+
+        if os.path.exists(prompt_path):
+            with open(prompt_path, 'r', encoding='utf-8') as f:
+                prompt = f.read()
+                # remove any newlines
+                prompt = prompt.replace('\n', ', ')
+                # remove new lines for all operating systems
+                prompt = prompt.replace('\r', ', ')
+                prompt_split = prompt.split(',')
+                # remove empty strings
+                prompt_split = [p.strip() for p in prompt_split if p.strip()]
+                # join back together
+                prompt = ', '.join(prompt_split)
+        else:
+            prompt = ''
+            # get default_prompt if it exists on the class instance
+            if hasattr(self, 'default_prompt'):
+                prompt = self.default_prompt
+            if hasattr(self, 'default_caption'):
+                prompt = self.default_caption
+        return prompt

toolkit/embedding.py

@@ -0,0 +1,185 @@
+import json
+import os
+from collections import OrderedDict
+
+import safetensors
+import torch
+from typing import TYPE_CHECKING
+
+from safetensors.torch import save_file
+
+from toolkit.metadata import get_meta_for_safetensors
+
+if TYPE_CHECKING:
+    from toolkit.stable_diffusion_model import StableDiffusion
+    from toolkit.config_modules import EmbeddingConfig
+
+
+# this is a frankenstein mix of automatic1111 and my own code
+
+class Embedding:
+    def __init__(
+            self,
+            sd: 'StableDiffusion',
+            embed_config: 'EmbeddingConfig'
+    ):
+        self.name = embed_config.trigger
+        self.sd = sd
+        self.embed_config = embed_config
+        # setup our embedding
+        # Add the placeholder token in tokenizer
+        placeholder_tokens = [self.embed_config.trigger]
+
+        # add dummy tokens for multi-vector
+        additional_tokens = []
+        for i in range(1, self.embed_config.tokens):
+            additional_tokens.append(f"{self.embed_config.trigger}_{i}")
+        placeholder_tokens += additional_tokens
+
+        num_added_tokens = self.sd.tokenizer.add_tokens(placeholder_tokens)
+        if num_added_tokens != self.embed_config.tokens:
+            raise ValueError(
+                f"The tokenizer already contains the token {self.embed_config.trigger}. Please pass a different"
+                " `placeholder_token` that is not already in the tokenizer."
+            )
+
+        # Convert the initializer_token, placeholder_token to ids
+        init_token_ids = self.sd.tokenizer.encode(self.embed_config.init_words, add_special_tokens=False)
+        # if length of token ids is more than number of orm embedding tokens fill with *
+        if len(init_token_ids) > self.embed_config.tokens:
+            init_token_ids = init_token_ids[:self.embed_config.tokens]
+        elif len(init_token_ids) < self.embed_config.tokens:
+            pad_token_id = self.sd.tokenizer.encode(["*"], add_special_tokens=False)
+            init_token_ids += pad_token_id * (self.embed_config.tokens - len(init_token_ids))
+
+        self.placeholder_token_ids = self.sd.tokenizer.convert_tokens_to_ids(placeholder_tokens)
+
+        # Resize the token embeddings as we are adding new special tokens to the tokenizer
+        # todo SDXL has 2 text encoders, need to do both for all of this
+        self.sd.text_encoder.resize_token_embeddings(len(self.sd.tokenizer))
+
+        # Initialise the newly added placeholder token with the embeddings of the initializer token
+        token_embeds = self.sd.text_encoder.get_input_embeddings().weight.data
+        with torch.no_grad():
+            for initializer_token_id, token_id in zip(init_token_ids, self.placeholder_token_ids):
+                token_embeds[token_id] = token_embeds[initializer_token_id].clone()
+
+        # this doesnt seem to be used again
+        self.token_embeds = token_embeds
+
+        # replace "[name] with this. This triggers it in the text encoder
+        self.embedding_tokens = " ".join(self.sd.tokenizer.convert_ids_to_tokens(self.placeholder_token_ids))
+
+    # returns the string to have in the prompt to trigger the embedding
+    def get_embedding_string(self):
+        return self.embedding_tokens
+
+    def get_trainable_params(self):
+        # todo only get this one as we could have more than one
+        return self.sd.text_encoder.get_input_embeddings().parameters()
+
+    # make setter and getter for vec
+    @property
+    def vec(self):
+        # should we get params instead
+        # create vector from token embeds
+        token_embeds = self.sd.text_encoder.get_input_embeddings().weight.data
+        # stack the tokens along batch axis adding that axis
+        new_vector = torch.stack(
+            [token_embeds[token_id].unsqueeze(0) for token_id in self.placeholder_token_ids],
+            dim=0
+        )
+        return new_vector
+
+    @vec.setter
+    def vec(self, new_vector):
+        # shape is (1, 768) for SD 1.5 for 1 token
+        token_embeds = self.sd.text_encoder.get_input_embeddings().weight.data
+        for i in range(new_vector.shape[0]):
+            # apply the weights to the placeholder tokens while preserving gradient
+            token_embeds[self.placeholder_token_ids[i]] = new_vector[i].clone()
+            x = 1
+
+    def save(self, filename):
+        # todo check to see how to get the vector out of the embedding
+
+        embedding_data = {
+            "string_to_token": {"*": 265},
+            "string_to_param": {"*": self.vec},
+            "name": self.name,
+            "step": 0,
+            # todo get these
+            "sd_checkpoint": None,
+            "sd_checkpoint_name": None,
+            "notes": None,
+        }
+        if filename.endswith('.pt'):
+            torch.save(embedding_data, filename)
+        elif filename.endswith('.bin'):
+            torch.save(embedding_data, filename)
+        elif filename.endswith('.safetensors'):
+            # save the embedding as a safetensors file
+            state_dict = {"emb_params": self.vec}
+            # add all embedding data (except string_to_param), to metadata
+            metadata = OrderedDict({k: json.dumps(v) for k, v in embedding_data.items() if k != "string_to_param"})
+            metadata["string_to_param"] = {"*": "emb_params"}
+            save_meta = get_meta_for_safetensors(metadata, name=self.name)
+            save_file(state_dict, filename, metadata=save_meta)
+
+    def load_embedding_from_file(self, file_path, device):
+        # full path
+        path = os.path.realpath(file_path)
+        filename = os.path.basename(path)
+        name, ext = os.path.splitext(filename)
+        ext = ext.upper()
+        if ext in ['.PNG', '.WEBP', '.JXL', '.AVIF']:
+            _, second_ext = os.path.splitext(name)
+            if second_ext.upper() == '.PREVIEW':
+                return
+
+        if ext in ['.BIN', '.PT']:
+            data = torch.load(path, map_location="cpu")
+        elif ext in ['.SAFETENSORS']:
+            # rebuild the embedding from the safetensors file if it has it
+            tensors = {}
+            with safetensors.torch.safe_open(path, framework="pt", device="cpu") as f:
+                metadata = f.metadata()
+                for k in f.keys():
+                    tensors[k] = f.get_tensor(k)
+            # data = safetensors.torch.load_file(path, device="cpu")
+            if metadata and 'string_to_param' in metadata and 'emb_params' in tensors:
+                # our format
+                def try_json(v):
+                    try:
+                        return json.loads(v)
+                    except:
+                        return v
+
+                data = {k: try_json(v) for k, v in metadata.items()}
+                data['string_to_param'] = {'*': tensors['emb_params']}
+            else:
+                # old format
+                data = tensors
+        else:
+            return
+
+        # textual inversion embeddings
+        if 'string_to_param' in data:
+            param_dict = data['string_to_param']
+            if hasattr(param_dict, '_parameters'):
+                param_dict = getattr(param_dict,
+                                     '_parameters')  # fix for torch 1.12.1 loading saved file from torch 1.11
+            assert len(param_dict) == 1, 'embedding file has multiple terms in it'
+            emb = next(iter(param_dict.items()))[1]
+        # diffuser concepts
+        elif type(data) == dict and type(next(iter(data.values()))) == torch.Tensor:
+            assert len(data.keys()) == 1, 'embedding file has multiple terms in it'
+
+            emb = next(iter(data.values()))
+            if len(emb.shape) == 1:
+                emb = emb.unsqueeze(0)
+        else:
+            raise Exception(
+                f"Couldn't identify {filename} as neither textual inversion embedding nor diffuser concept.")
+
+        self.vec = emb.detach().to(device, dtype=torch.float32)

toolkit/stable_diffusion_model.py

@@ -520,6 +520,11 @@ class StableDiffusion:
                         noise_pred_text - noise_pred_uncond
                 )
 
+                # https://github.com/huggingface/diffusers/blob/7a91ea6c2b53f94da930a61ed571364022b21044/src/diffusers/pipelines/stable_diffusion_xl/pipeline_stable_diffusion_xl.py#L775
+                if guidance_rescale > 0.0:
+                    # Based on 3.4. in https://arxiv.org/pdf/2305.08891.pdf
+                    noise_pred = rescale_noise_cfg(noise_pred, noise_pred_text, guidance_rescale=guidance_rescale)
+
         return noise_pred
 
     # ref: https://github.com/huggingface/diffusers/blob/0bab447670f47c28df60fbd2f6a0f833f75a16f5/src/diffusers/pipelines/stable_diffusion/pipeline_stable_diffusion.py#L746