| import inspect |
| from typing import Any, Dict, List, Optional, Union |
|
|
| import torch |
| import torch.nn as nn |
| from transformers import AutoModel, AutoTokenizer, CLIPImageProcessor |
|
|
| from diffusers import DiffusionPipeline |
| from diffusers.image_processor import VaeImageProcessor |
| from diffusers.loaders import StableDiffusionLoraLoaderMixin |
| from diffusers.models import AutoencoderKL, UNet2DConditionModel |
| from diffusers.models.lora import adjust_lora_scale_text_encoder |
| from diffusers.pipelines.pipeline_utils import StableDiffusionMixin |
| from diffusers.pipelines.stable_diffusion.pipeline_output import StableDiffusionPipelineOutput |
| from diffusers.pipelines.stable_diffusion.safety_checker import StableDiffusionSafetyChecker |
| from diffusers.schedulers import KarrasDiffusionSchedulers |
| from diffusers.utils import ( |
| USE_PEFT_BACKEND, |
| logging, |
| scale_lora_layers, |
| unscale_lora_layers, |
| ) |
| from diffusers.utils.torch_utils import randn_tensor |
|
|
|
|
| logger = logging.get_logger(__name__) |
|
|
|
|
| class TranslatorBase(nn.Module): |
| def __init__(self, num_tok, dim, dim_out, mult=2): |
| super().__init__() |
|
|
| self.dim_in = dim |
| self.dim_out = dim_out |
|
|
| self.net_tok = nn.Sequential( |
| nn.Linear(num_tok, int(num_tok * mult)), |
| nn.LayerNorm(int(num_tok * mult)), |
| nn.GELU(), |
| nn.Linear(int(num_tok * mult), int(num_tok * mult)), |
| nn.LayerNorm(int(num_tok * mult)), |
| nn.GELU(), |
| nn.Linear(int(num_tok * mult), num_tok), |
| nn.LayerNorm(num_tok), |
| ) |
|
|
| self.net_sen = nn.Sequential( |
| nn.Linear(dim, int(dim * mult)), |
| nn.LayerNorm(int(dim * mult)), |
| nn.GELU(), |
| nn.Linear(int(dim * mult), int(dim * mult)), |
| nn.LayerNorm(int(dim * mult)), |
| nn.GELU(), |
| nn.Linear(int(dim * mult), dim_out), |
| nn.LayerNorm(dim_out), |
| ) |
|
|
| def forward(self, x): |
| if self.dim_in == self.dim_out: |
| indentity_0 = x |
| x = self.net_sen(x) |
| x += indentity_0 |
| x = x.transpose(1, 2) |
|
|
| indentity_1 = x |
| x = self.net_tok(x) |
| x += indentity_1 |
| x = x.transpose(1, 2) |
| else: |
| x = self.net_sen(x) |
| x = x.transpose(1, 2) |
|
|
| x = self.net_tok(x) |
| x = x.transpose(1, 2) |
| return x |
|
|
|
|
| class TranslatorBaseNoLN(nn.Module): |
| def __init__(self, num_tok, dim, dim_out, mult=2): |
| super().__init__() |
|
|
| self.dim_in = dim |
| self.dim_out = dim_out |
|
|
| self.net_tok = nn.Sequential( |
| nn.Linear(num_tok, int(num_tok * mult)), |
| nn.GELU(), |
| nn.Linear(int(num_tok * mult), int(num_tok * mult)), |
| nn.GELU(), |
| nn.Linear(int(num_tok * mult), num_tok), |
| ) |
|
|
| self.net_sen = nn.Sequential( |
| nn.Linear(dim, int(dim * mult)), |
| nn.GELU(), |
| nn.Linear(int(dim * mult), int(dim * mult)), |
| nn.GELU(), |
| nn.Linear(int(dim * mult), dim_out), |
| ) |
|
|
| def forward(self, x): |
| if self.dim_in == self.dim_out: |
| indentity_0 = x |
| x = self.net_sen(x) |
| x += indentity_0 |
| x = x.transpose(1, 2) |
|
|
| indentity_1 = x |
| x = self.net_tok(x) |
| x += indentity_1 |
| x = x.transpose(1, 2) |
| else: |
| x = self.net_sen(x) |
| x = x.transpose(1, 2) |
|
|
| x = self.net_tok(x) |
| x = x.transpose(1, 2) |
| return x |
|
|
|
|
| class TranslatorNoLN(nn.Module): |
| def __init__(self, num_tok, dim, dim_out, mult=2, depth=5): |
| super().__init__() |
|
|
| self.blocks = nn.ModuleList([TranslatorBase(num_tok, dim, dim, mult=2) for d in range(depth)]) |
| self.gelu = nn.GELU() |
|
|
| self.tail = TranslatorBaseNoLN(num_tok, dim, dim_out, mult=2) |
|
|
| def forward(self, x): |
| for block in self.blocks: |
| x = block(x) + x |
| x = self.gelu(x) |
|
|
| x = self.tail(x) |
| return x |
|
|
|
|
| def rescale_noise_cfg(noise_cfg, noise_pred_text, guidance_rescale=0.0): |
| """ |
| Rescale `noise_cfg` according to `guidance_rescale`. Based on findings of [Common Diffusion Noise Schedules and |
| Sample Steps are Flawed](https://huggingface.co/papers/2305.08891). See Section 3.4 |
| """ |
| std_text = noise_pred_text.std(dim=list(range(1, noise_pred_text.ndim)), keepdim=True) |
| std_cfg = noise_cfg.std(dim=list(range(1, noise_cfg.ndim)), keepdim=True) |
| |
| noise_pred_rescaled = noise_cfg * (std_text / std_cfg) |
| |
| noise_cfg = guidance_rescale * noise_pred_rescaled + (1 - guidance_rescale) * noise_cfg |
| return noise_cfg |
|
|
|
|
| def retrieve_timesteps( |
| scheduler, |
| num_inference_steps: Optional[int] = None, |
| device: Optional[Union[str, torch.device]] = None, |
| timesteps: Optional[List[int]] = None, |
| **kwargs, |
| ): |
| """ |
| Calls the scheduler's `set_timesteps` method and retrieves timesteps from the scheduler after the call. Handles |
| custom timesteps. Any kwargs will be supplied to `scheduler.set_timesteps`. |
| |
| Args: |
| scheduler (`SchedulerMixin`): |
| The scheduler to get timesteps from. |
| num_inference_steps (`int`): |
| The number of diffusion steps used when generating samples with a pre-trained model. If used, |
| `timesteps` must be `None`. |
| device (`str` or `torch.device`, *optional*): |
| The device to which the timesteps should be moved to. If `None`, the timesteps are not moved. |
| timesteps (`List[int]`, *optional*): |
| Custom timesteps used to support arbitrary spacing between timesteps. If `None`, then the default |
| timestep spacing strategy of the scheduler is used. If `timesteps` is passed, `num_inference_steps` |
| must be `None`. |
| |
| Returns: |
| `Tuple[torch.Tensor, int]`: A tuple where the first element is the timestep schedule from the scheduler and the |
| second element is the number of inference steps. |
| """ |
| if timesteps is not None: |
| accepts_timesteps = "timesteps" in set(inspect.signature(scheduler.set_timesteps).parameters.keys()) |
| if not accepts_timesteps: |
| raise ValueError( |
| f"The current scheduler class {scheduler.__class__}'s `set_timesteps` does not support custom" |
| f" timestep schedules. Please check whether you are using the correct scheduler." |
| ) |
| scheduler.set_timesteps(timesteps=timesteps, device=device, **kwargs) |
| timesteps = scheduler.timesteps |
| num_inference_steps = len(timesteps) |
| else: |
| scheduler.set_timesteps(num_inference_steps, device=device, **kwargs) |
| timesteps = scheduler.timesteps |
| return timesteps, num_inference_steps |
|
|
|
|
| class GlueGenStableDiffusionPipeline(DiffusionPipeline, StableDiffusionMixin, StableDiffusionLoraLoaderMixin): |
| def __init__( |
| self, |
| vae: AutoencoderKL, |
| text_encoder: AutoModel, |
| tokenizer: AutoTokenizer, |
| unet: UNet2DConditionModel, |
| scheduler: KarrasDiffusionSchedulers, |
| safety_checker: StableDiffusionSafetyChecker, |
| feature_extractor: CLIPImageProcessor, |
| language_adapter: TranslatorNoLN = None, |
| tensor_norm: torch.Tensor = None, |
| requires_safety_checker: bool = True, |
| ): |
| super().__init__() |
|
|
| self.register_modules( |
| vae=vae, |
| text_encoder=text_encoder, |
| tokenizer=tokenizer, |
| unet=unet, |
| scheduler=scheduler, |
| safety_checker=safety_checker, |
| feature_extractor=feature_extractor, |
| language_adapter=language_adapter, |
| tensor_norm=tensor_norm, |
| ) |
| self.vae_scale_factor = 2 ** (len(self.vae.config.block_out_channels) - 1) if getattr(self, "vae", None) else 8 |
| self.image_processor = VaeImageProcessor(vae_scale_factor=self.vae_scale_factor) |
| self.register_to_config(requires_safety_checker=requires_safety_checker) |
|
|
| def load_language_adapter( |
| self, |
| model_path: str, |
| num_token: int, |
| dim: int, |
| dim_out: int, |
| tensor_norm: torch.Tensor, |
| mult: int = 2, |
| depth: int = 5, |
| ): |
| device = self._execution_device |
| self.tensor_norm = tensor_norm.to(device) |
| self.language_adapter = TranslatorNoLN(num_tok=num_token, dim=dim, dim_out=dim_out, mult=mult, depth=depth).to( |
| device |
| ) |
| self.language_adapter.load_state_dict(torch.load(model_path)) |
|
|
| def _adapt_language(self, prompt_embeds: torch.Tensor): |
| prompt_embeds = prompt_embeds / 3 |
| prompt_embeds = self.language_adapter(prompt_embeds) * (self.tensor_norm / 2) |
| return prompt_embeds |
|
|
| def encode_prompt( |
| self, |
| prompt, |
| device, |
| num_images_per_prompt, |
| do_classifier_free_guidance, |
| negative_prompt=None, |
| prompt_embeds: Optional[torch.Tensor] = None, |
| negative_prompt_embeds: Optional[torch.Tensor] = None, |
| lora_scale: Optional[float] = None, |
| clip_skip: Optional[int] = None, |
| ): |
| r""" |
| Encodes the prompt into text encoder hidden states. |
| |
| Args: |
| prompt (`str` or `List[str]`, *optional*): |
| prompt to be encoded |
| device: (`torch.device`): |
| torch device |
| num_images_per_prompt (`int`): |
| number of images that should be generated per prompt |
| do_classifier_free_guidance (`bool`): |
| whether to use classifier free guidance or not |
| negative_prompt (`str` or `List[str]`, *optional*): |
| The prompt or prompts not to guide the image generation. If not defined, one has to pass |
| `negative_prompt_embeds` instead. Ignored when not using guidance (i.e., ignored if `guidance_scale` is |
| less than `1`). |
| prompt_embeds (`torch.Tensor`, *optional*): |
| Pre-generated text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt weighting. If not |
| provided, text embeddings will be generated from `prompt` input argument. |
| negative_prompt_embeds (`torch.Tensor`, *optional*): |
| Pre-generated negative text embeddings. Can be used to easily tweak text inputs, *e.g.* prompt |
| weighting. If not provided, negative_prompt_embeds will be generated from `negative_prompt` input |
| argument. |
| lora_scale (`float`, *optional*): |
| A LoRA scale that will be applied to all LoRA layers of the text encoder if LoRA layers are loaded. |
| clip_skip (`int`, *optional*): |
| Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that |
| the output of the pre-final layer will be used for computing the prompt embeddings. |
| """ |
| |
| |
| if lora_scale is not None and isinstance(self, StableDiffusionLoraLoaderMixin): |
| self._lora_scale = lora_scale |
|
|
| |
| if not USE_PEFT_BACKEND: |
| adjust_lora_scale_text_encoder(self.text_encoder, lora_scale) |
| else: |
| scale_lora_layers(self.text_encoder, lora_scale) |
|
|
| if prompt is not None and isinstance(prompt, str): |
| batch_size = 1 |
| elif prompt is not None and isinstance(prompt, list): |
| batch_size = len(prompt) |
| else: |
| batch_size = prompt_embeds.shape[0] |
|
|
| if prompt_embeds is None: |
| text_inputs = self.tokenizer( |
| prompt, |
| padding="max_length", |
| max_length=self.tokenizer.model_max_length, |
| truncation=True, |
| return_tensors="pt", |
| ) |
| text_input_ids = text_inputs.input_ids |
| untruncated_ids = self.tokenizer(prompt, padding="longest", return_tensors="pt").input_ids |
|
|
| if untruncated_ids.shape[-1] >= text_input_ids.shape[-1] and not torch.equal( |
| text_input_ids, untruncated_ids |
| ): |
| removed_text = self.tokenizer.batch_decode( |
| untruncated_ids[:, self.tokenizer.model_max_length - 1 : -1] |
| ) |
| logger.warning( |
| "The following part of your input was truncated because CLIP can only handle sequences up to" |
| f" {self.tokenizer.model_max_length} tokens: {removed_text}" |
| ) |
|
|
| if hasattr(self.text_encoder.config, "use_attention_mask") and self.text_encoder.config.use_attention_mask: |
| attention_mask = text_inputs.attention_mask.to(device) |
| elif self.language_adapter is not None: |
| attention_mask = text_inputs.attention_mask.to(device) |
| else: |
| attention_mask = None |
|
|
| if clip_skip is None: |
| prompt_embeds = self.text_encoder(text_input_ids.to(device), attention_mask=attention_mask) |
| prompt_embeds = prompt_embeds[0] |
|
|
| else: |
| prompt_embeds = self.text_encoder( |
| text_input_ids.to(device), attention_mask=attention_mask, output_hidden_states=True |
| ) |
| |
| |
| |
| prompt_embeds = prompt_embeds[-1][-(clip_skip + 1)] |
| |
| |
| |
| |
| prompt_embeds = self.text_encoder.text_model.final_layer_norm(prompt_embeds) |
|
|
| |
| if self.language_adapter is not None: |
| prompt_embeds = self._adapt_language(prompt_embeds) |
|
|
| if self.text_encoder is not None: |
| prompt_embeds_dtype = self.text_encoder.dtype |
| elif self.unet is not None: |
| prompt_embeds_dtype = self.unet.dtype |
| else: |
| prompt_embeds_dtype = prompt_embeds.dtype |
|
|
| prompt_embeds = prompt_embeds.to(dtype=prompt_embeds_dtype, device=device) |
|
|
| bs_embed, seq_len, _ = prompt_embeds.shape |
| |
| prompt_embeds = prompt_embeds.repeat(1, num_images_per_prompt, 1) |
| prompt_embeds = prompt_embeds.view(bs_embed * num_images_per_prompt, seq_len, -1) |
|
|
| |
| if do_classifier_free_guidance and negative_prompt_embeds is None: |
| uncond_tokens: List[str] |
| if negative_prompt is None: |
| uncond_tokens = [""] * batch_size |
| elif prompt is not None and type(prompt) is not type(negative_prompt): |
| raise TypeError( |
| f"`negative_prompt` should be the same type to `prompt`, but got {type(negative_prompt)} !=" |
| f" {type(prompt)}." |
| ) |
| elif isinstance(negative_prompt, str): |
| uncond_tokens = [negative_prompt] |
| elif batch_size != len(negative_prompt): |
| raise ValueError( |
| f"`negative_prompt`: {negative_prompt} has batch size {len(negative_prompt)}, but `prompt`:" |
| f" {prompt} has batch size {batch_size}. Please make sure that passed `negative_prompt` matches" |
| " the batch size of `prompt`." |
| ) |
| else: |
| uncond_tokens = negative_prompt |
|
|
| max_length = prompt_embeds.shape[1] |
| uncond_input = self.tokenizer( |
| uncond_tokens, |
| padding="max_length", |
| max_length=max_length, |
| truncation=True, |
| return_tensors="pt", |
| ) |
|
|
| if hasattr(self.text_encoder.config, "use_attention_mask") and self.text_encoder.config.use_attention_mask: |
| attention_mask = uncond_input.attention_mask.to(device) |
| else: |
| attention_mask = None |
|
|
| negative_prompt_embeds = self.text_encoder( |
| uncond_input.input_ids.to(device), |
| attention_mask=attention_mask, |
| ) |
| negative_prompt_embeds = negative_prompt_embeds[0] |
| |
| if self.language_adapter is not None: |
| negative_prompt_embeds = self._adapt_language(negative_prompt_embeds) |
|
|
| if do_classifier_free_guidance: |
| |
| seq_len = negative_prompt_embeds.shape[1] |
|
|
| negative_prompt_embeds = negative_prompt_embeds.to(dtype=prompt_embeds_dtype, device=device) |
|
|
| negative_prompt_embeds = negative_prompt_embeds.repeat(1, num_images_per_prompt, 1) |
| negative_prompt_embeds = negative_prompt_embeds.view(batch_size * num_images_per_prompt, seq_len, -1) |
|
|
| if isinstance(self, StableDiffusionLoraLoaderMixin) and USE_PEFT_BACKEND: |
| |
| unscale_lora_layers(self.text_encoder, lora_scale) |
|
|
| return prompt_embeds, negative_prompt_embeds |
|
|
| def run_safety_checker(self, image, device, dtype): |
| if self.safety_checker is None: |
| has_nsfw_concept = None |
| else: |
| if torch.is_tensor(image): |
| feature_extractor_input = self.image_processor.postprocess(image, output_type="pil") |
| else: |
| feature_extractor_input = self.image_processor.numpy_to_pil(image) |
| safety_checker_input = self.feature_extractor(feature_extractor_input, return_tensors="pt").to(device) |
| image, has_nsfw_concept = self.safety_checker( |
| images=image, clip_input=safety_checker_input.pixel_values.to(dtype) |
| ) |
| return image, has_nsfw_concept |
|
|
| def prepare_extra_step_kwargs(self, generator, eta): |
| |
| |
| |
| |
|
|
| accepts_eta = "eta" in set(inspect.signature(self.scheduler.step).parameters.keys()) |
| extra_step_kwargs = {} |
| if accepts_eta: |
| extra_step_kwargs["eta"] = eta |
|
|
| |
| accepts_generator = "generator" in set(inspect.signature(self.scheduler.step).parameters.keys()) |
| if accepts_generator: |
| extra_step_kwargs["generator"] = generator |
| return extra_step_kwargs |
|
|
| def check_inputs( |
| self, |
| prompt, |
| height, |
| width, |
| negative_prompt=None, |
| prompt_embeds=None, |
| negative_prompt_embeds=None, |
| ): |
| if height % 8 != 0 or width % 8 != 0: |
| raise ValueError(f"`height` and `width` have to be divisible by 8 but are {height} and {width}.") |
|
|
| if prompt is not None and prompt_embeds is not None: |
| raise ValueError( |
| f"Cannot forward both `prompt`: {prompt} and `prompt_embeds`: {prompt_embeds}. Please make sure to" |
| " only forward one of the two." |
| ) |
| elif prompt is None and prompt_embeds is None: |
| raise ValueError( |
| "Provide either `prompt` or `prompt_embeds`. Cannot leave both `prompt` and `prompt_embeds` undefined." |
| ) |
| elif prompt is not None and (not isinstance(prompt, str) and not isinstance(prompt, list)): |
| raise ValueError(f"`prompt` has to be of type `str` or `list` but is {type(prompt)}") |
|
|
| if negative_prompt is not None and negative_prompt_embeds is not None: |
| raise ValueError( |
| f"Cannot forward both `negative_prompt`: {negative_prompt} and `negative_prompt_embeds`:" |
| f" {negative_prompt_embeds}. Please make sure to only forward one of the two." |
| ) |
|
|
| if prompt_embeds is not None and negative_prompt_embeds is not None: |
| if prompt_embeds.shape != negative_prompt_embeds.shape: |
| raise ValueError( |
| "`prompt_embeds` and `negative_prompt_embeds` must have the same shape when passed directly, but" |
| f" got: `prompt_embeds` {prompt_embeds.shape} != `negative_prompt_embeds`" |
| f" {negative_prompt_embeds.shape}." |
| ) |
|
|
| def prepare_latents(self, batch_size, num_channels_latents, height, width, dtype, device, generator, latents=None): |
| shape = ( |
| batch_size, |
| num_channels_latents, |
| int(height) // self.vae_scale_factor, |
| int(width) // self.vae_scale_factor, |
| ) |
| if isinstance(generator, list) and len(generator) != batch_size: |
| raise ValueError( |
| f"You have passed a list of generators of length {len(generator)}, but requested an effective batch" |
| f" size of {batch_size}. Make sure the batch size matches the length of the generators." |
| ) |
|
|
| if latents is None: |
| latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype) |
| else: |
| latents = latents.to(device) |
|
|
| |
| latents = latents * self.scheduler.init_noise_sigma |
| return latents |
|
|
| |
| def get_guidance_scale_embedding(self, w, embedding_dim=512, dtype=torch.float32): |
| """ |
| See https://github.com/google-research/vdm/blob/dc27b98a554f65cdc654b800da5aa1846545d41b/model_vdm.py#L298 |
| |
| Args: |
| timesteps (`torch.Tensor`): |
| generate embedding vectors at these timesteps |
| embedding_dim (`int`, *optional*, defaults to 512): |
| dimension of the embeddings to generate |
| dtype: |
| data type of the generated embeddings |
| |
| Returns: |
| `torch.Tensor`: Embedding vectors with shape `(len(timesteps), embedding_dim)` |
| """ |
| assert len(w.shape) == 1 |
| w = w * 1000.0 |
|
|
| half_dim = embedding_dim // 2 |
| emb = torch.log(torch.tensor(10000.0)) / (half_dim - 1) |
| emb = torch.exp(torch.arange(half_dim, dtype=dtype) * -emb) |
| emb = w.to(dtype)[:, None] * emb[None, :] |
| emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1) |
| if embedding_dim % 2 == 1: |
| emb = torch.nn.functional.pad(emb, (0, 1)) |
| assert emb.shape == (w.shape[0], embedding_dim) |
| return emb |
|
|
| @property |
| def guidance_scale(self): |
| return self._guidance_scale |
|
|
| @property |
| def guidance_rescale(self): |
| return self._guidance_rescale |
|
|
| @property |
| def clip_skip(self): |
| return self._clip_skip |
|
|
| |
| |
| |
| @property |
| def do_classifier_free_guidance(self): |
| return self._guidance_scale > 1 and self.unet.config.time_cond_proj_dim is None |
|
|
| @property |
| def cross_attention_kwargs(self): |
| return self._cross_attention_kwargs |
|
|
| @property |
| def num_timesteps(self): |
| return self._num_timesteps |
|
|
| @property |
| def interrupt(self): |
| return self._interrupt |
|
|
| @torch.no_grad() |
| def __call__( |
| self, |
| prompt: Union[str, List[str]] = None, |
| height: Optional[int] = None, |
| width: Optional[int] = None, |
| num_inference_steps: int = 50, |
| timesteps: List[int] = None, |
| guidance_scale: float = 7.5, |
| negative_prompt: Optional[Union[str, List[str]]] = None, |
| num_images_per_prompt: Optional[int] = 1, |
| eta: float = 0.0, |
| generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None, |
| latents: Optional[torch.Tensor] = None, |
| prompt_embeds: Optional[torch.Tensor] = None, |
| negative_prompt_embeds: Optional[torch.Tensor] = None, |
| output_type: Optional[str] = "pil", |
| return_dict: bool = True, |
| cross_attention_kwargs: Optional[Dict[str, Any]] = None, |
| guidance_rescale: float = 0.0, |
| clip_skip: Optional[int] = None, |
| **kwargs, |
| ): |
| r""" |
| The call function to the pipeline for generation. |
| |
| Args: |
| prompt (`str` or `List[str]`, *optional*): |
| The prompt or prompts to guide image generation. If not defined, you need to pass `prompt_embeds`. |
| height (`int`, *optional*, defaults to `self.unet.config.sample_size * self.vae_scale_factor`): |
| The height in pixels of the generated image. |
| width (`int`, *optional*, defaults to `self.unet.config.sample_size * self.vae_scale_factor`): |
| The width in pixels of the generated image. |
| num_inference_steps (`int`, *optional*, defaults to 50): |
| The number of denoising steps. More denoising steps usually lead to a higher quality image at the |
| expense of slower inference. |
| timesteps (`List[int]`, *optional*): |
| Custom timesteps to use for the denoising process with schedulers which support a `timesteps` argument |
| in their `set_timesteps` method. If not defined, the default behavior when `num_inference_steps` is |
| passed will be used. Must be in descending order. |
| guidance_scale (`float`, *optional*, defaults to 7.5): |
| A higher guidance scale value encourages the model to generate images closely linked to the text |
| `prompt` at the expense of lower image quality. Guidance scale is enabled when `guidance_scale > 1`. |
| negative_prompt (`str` or `List[str]`, *optional*): |
| The prompt or prompts to guide what to not include in image generation. If not defined, you need to |
| pass `negative_prompt_embeds` instead. Ignored when not using guidance (`guidance_scale < 1`). |
| num_images_per_prompt (`int`, *optional*, defaults to 1): |
| The number of images to generate per prompt. |
| eta (`float`, *optional*, defaults to 0.0): |
| Corresponds to parameter eta (η) from the [DDIM](https://huggingface.co/papers/2010.02502) paper. Only applies |
| to the [`~schedulers.DDIMScheduler`], and is ignored in other schedulers. |
| generator (`torch.Generator` or `List[torch.Generator]`, *optional*): |
| A [`torch.Generator`](https://pytorch.org/docs/stable/generated/torch.Generator.html) to make |
| generation deterministic. |
| latents (`torch.Tensor`, *optional*): |
| Pre-generated noisy latents sampled from a Gaussian distribution, to be used as inputs for image |
| generation. Can be used to tweak the same generation with different prompts. If not provided, a latents |
| tensor is generated by sampling using the supplied random `generator`. |
| prompt_embeds (`torch.Tensor`, *optional*): |
| Pre-generated text embeddings. Can be used to easily tweak text inputs (prompt weighting). If not |
| provided, text embeddings are generated from the `prompt` input argument. |
| negative_prompt_embeds (`torch.Tensor`, *optional*): |
| Pre-generated negative text embeddings. Can be used to easily tweak text inputs (prompt weighting). If |
| not provided, `negative_prompt_embeds` are generated from the `negative_prompt` input argument. |
| ip_adapter_image: (`PipelineImageInput`, *optional*): Optional image input to work with IP Adapters. |
| output_type (`str`, *optional*, defaults to `"pil"`): |
| The output format of the generated image. Choose between `PIL.Image` or `np.array`. |
| return_dict (`bool`, *optional*, defaults to `True`): |
| Whether or not to return a [`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] instead of a |
| plain tuple. |
| cross_attention_kwargs (`dict`, *optional*): |
| A kwargs dictionary that if specified is passed along to the [`AttentionProcessor`] as defined in |
| [`self.processor`](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py). |
| guidance_rescale (`float`, *optional*, defaults to 0.0): |
| Guidance rescale factor from [Common Diffusion Noise Schedules and Sample Steps are |
| Flawed](https://huggingface.co/papers/2305.08891). Guidance rescale factor should fix overexposure when |
| using zero terminal SNR. |
| clip_skip (`int`, *optional*): |
| Number of layers to be skipped from CLIP while computing the prompt embeddings. A value of 1 means that |
| the output of the pre-final layer will be used for computing the prompt embeddings. |
| |
| Examples: |
| |
| Returns: |
| [`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] or `tuple`: |
| If `return_dict` is `True`, [`~pipelines.stable_diffusion.StableDiffusionPipelineOutput`] is returned, |
| otherwise a `tuple` is returned where the first element is a list with the generated images and the |
| second element is a list of `bool`s indicating whether the corresponding generated image contains |
| "not-safe-for-work" (nsfw) content. |
| """ |
|
|
| |
| height = height or self.unet.config.sample_size * self.vae_scale_factor |
| width = width or self.unet.config.sample_size * self.vae_scale_factor |
| |
|
|
| |
| self.check_inputs( |
| prompt, |
| height, |
| width, |
| negative_prompt, |
| prompt_embeds, |
| negative_prompt_embeds, |
| ) |
|
|
| self._guidance_scale = guidance_scale |
| self._guidance_rescale = guidance_rescale |
| self._clip_skip = clip_skip |
| self._cross_attention_kwargs = cross_attention_kwargs |
| self._interrupt = False |
|
|
| |
| if prompt is not None and isinstance(prompt, str): |
| batch_size = 1 |
| elif prompt is not None and isinstance(prompt, list): |
| batch_size = len(prompt) |
| else: |
| batch_size = prompt_embeds.shape[0] |
|
|
| device = self._execution_device |
|
|
| |
| lora_scale = ( |
| self.cross_attention_kwargs.get("scale", None) if self.cross_attention_kwargs is not None else None |
| ) |
|
|
| prompt_embeds, negative_prompt_embeds = self.encode_prompt( |
| prompt, |
| device, |
| num_images_per_prompt, |
| self.do_classifier_free_guidance, |
| negative_prompt, |
| prompt_embeds=prompt_embeds, |
| negative_prompt_embeds=negative_prompt_embeds, |
| lora_scale=lora_scale, |
| clip_skip=self.clip_skip, |
| ) |
|
|
| |
| |
| |
| if self.do_classifier_free_guidance: |
| prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds]) |
|
|
| |
| timesteps, num_inference_steps = retrieve_timesteps(self.scheduler, num_inference_steps, device, timesteps) |
|
|
| |
| num_channels_latents = self.unet.config.in_channels |
| latents = self.prepare_latents( |
| batch_size * num_images_per_prompt, |
| num_channels_latents, |
| height, |
| width, |
| prompt_embeds.dtype, |
| device, |
| generator, |
| latents, |
| ) |
|
|
| |
| extra_step_kwargs = self.prepare_extra_step_kwargs(generator, eta) |
|
|
| |
| timestep_cond = None |
| if self.unet.config.time_cond_proj_dim is not None: |
| guidance_scale_tensor = torch.tensor(self.guidance_scale - 1).repeat(batch_size * num_images_per_prompt) |
| timestep_cond = self.get_guidance_scale_embedding( |
| guidance_scale_tensor, embedding_dim=self.unet.config.time_cond_proj_dim |
| ).to(device=device, dtype=latents.dtype) |
|
|
| |
| num_warmup_steps = len(timesteps) - num_inference_steps * self.scheduler.order |
| self._num_timesteps = len(timesteps) |
| with self.progress_bar(total=num_inference_steps) as progress_bar: |
| for i, t in enumerate(timesteps): |
| if self.interrupt: |
| continue |
|
|
| |
| latent_model_input = torch.cat([latents] * 2) if self.do_classifier_free_guidance else latents |
| latent_model_input = self.scheduler.scale_model_input(latent_model_input, t) |
|
|
| |
| noise_pred = self.unet( |
| latent_model_input, |
| t, |
| encoder_hidden_states=prompt_embeds, |
| timestep_cond=timestep_cond, |
| cross_attention_kwargs=self.cross_attention_kwargs, |
| return_dict=False, |
| )[0] |
|
|
| |
| if self.do_classifier_free_guidance: |
| noise_pred_uncond, noise_pred_text = noise_pred.chunk(2) |
| noise_pred = noise_pred_uncond + self.guidance_scale * (noise_pred_text - noise_pred_uncond) |
|
|
| if self.do_classifier_free_guidance and self.guidance_rescale > 0.0: |
| |
| noise_pred = rescale_noise_cfg(noise_pred, noise_pred_text, guidance_rescale=self.guidance_rescale) |
|
|
| |
| latents = self.scheduler.step(noise_pred, t, latents, **extra_step_kwargs, return_dict=False)[0] |
|
|
| |
| if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0): |
| progress_bar.update() |
|
|
| if not output_type == "latent": |
| image = self.vae.decode(latents / self.vae.config.scaling_factor, return_dict=False, generator=generator)[ |
| 0 |
| ] |
| image, has_nsfw_concept = self.run_safety_checker(image, device, prompt_embeds.dtype) |
| else: |
| image = latents |
| has_nsfw_concept = None |
|
|
| if has_nsfw_concept is None: |
| do_denormalize = [True] * image.shape[0] |
| else: |
| do_denormalize = [not has_nsfw for has_nsfw in has_nsfw_concept] |
|
|
| image = self.image_processor.postprocess(image, output_type=output_type, do_denormalize=do_denormalize) |
|
|
| |
| self.maybe_free_model_hooks() |
|
|
| if not return_dict: |
| return (image, has_nsfw_concept) |
|
|
| return StableDiffusionPipelineOutput(images=image, nsfw_content_detected=has_nsfw_concept) |
|
|