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import torch |
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import numpy as np |
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import html |
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import inspect |
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import re |
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import urllib.parse as ul |
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from transformers import CLIPTextModel, CLIPTokenizer, T5EncoderModel, T5TokenizerFast, CLIPTextModelWithProjection |
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from diffusers import FlowMatchEulerDiscreteScheduler, AutoPipelineForImage2Image, FluxPipeline, FluxTransformer2DModel |
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from diffusers import StableDiffusion3Pipeline, AutoencoderKL, DiffusionPipeline, ImagePipelineOutput |
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from diffusers.image_processor import VaeImageProcessor |
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from diffusers.loaders import FluxLoraLoaderMixin, FromSingleFileMixin, SD3LoraLoaderMixin |
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from diffusers.utils import ( |
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USE_PEFT_BACKEND, |
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is_torch_xla_available, |
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logging, |
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BACKENDS_MAPPING, |
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deprecate, |
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replace_example_docstring, |
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scale_lora_layers, |
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unscale_lora_layers, |
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) |
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from diffusers.utils.torch_utils import randn_tensor |
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from diffusers.pipelines.flux.pipeline_output import FluxPipelineOutput |
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from typing import Any, Callable, Dict, List, Optional, Union |
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from PIL import Image |
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from diffusers.pipelines.flux.pipeline_flux import calculate_shift, retrieve_timesteps, FluxTransformer2DModel |
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from diffusers.utils import is_torch_xla_available |
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|
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if is_torch_xla_available(): |
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import torch_xla.core.xla_model as xm |
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|
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XLA_AVAILABLE = True |
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else: |
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XLA_AVAILABLE = False |
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|
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logger = logging.get_logger(__name__) |
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BASE_SEQ_LEN = 256 |
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MAX_SEQ_LEN = 4096 |
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BASE_SHIFT = 0.5 |
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MAX_SHIFT = 1.16 |
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|
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def calculate_timestep_shift(image_seq_len: int) -> float: |
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"""Calculates the timestep shift (mu) based on the image sequence length.""" |
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m = (MAX_SHIFT - BASE_SHIFT) / (MAX_SEQ_LEN - BASE_SEQ_LEN) |
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b = BASE_SHIFT - m * BASE_SEQ_LEN |
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mu = image_seq_len * m + b |
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return mu |
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|
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def prepare_timesteps( |
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scheduler: FlowMatchEulerDiscreteScheduler, |
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num_inference_steps: Optional[int] = None, |
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device: Optional[Union[str, torch.device]] = None, |
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timesteps: Optional[List[int]] = None, |
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sigmas: Optional[List[float]] = None, |
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mu: Optional[float] = None, |
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) -> (torch.Tensor, int): |
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"""Prepares the timesteps for the diffusion process.""" |
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if timesteps is not None and sigmas is not None: |
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raise ValueError("Only one of `timesteps` or `sigmas` can be passed.") |
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|
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if timesteps is not None: |
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scheduler.set_timesteps(timesteps=timesteps, device=device) |
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elif sigmas is not None: |
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scheduler.set_timesteps(sigmas=sigmas, device=device) |
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else: |
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scheduler.set_timesteps(num_inference_steps, device=device, mu=mu) |
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|
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timesteps = scheduler.timesteps |
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num_inference_steps = len(timesteps) |
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return timesteps, num_inference_steps |
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|
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class FluxWithCFGPipeline(DiffusionPipeline, FluxLoraLoaderMixin, FromSingleFileMixin): |
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def __init__( |
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self, |
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scheduler: FlowMatchEulerDiscreteScheduler, |
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vae: AutoencoderKL, |
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text_encoder: CLIPTextModel, |
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tokenizer: CLIPTokenizer, |
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text_encoder_2: T5EncoderModel, |
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tokenizer_2: T5TokenizerFast, |
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transformer: FluxTransformer2DModel, |
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): |
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super().__init__() |
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|
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self.register_modules( |
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vae=vae, |
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text_encoder=text_encoder, |
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text_encoder_2=text_encoder_2, |
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tokenizer=tokenizer, |
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tokenizer_2=tokenizer_2, |
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transformer=transformer, |
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scheduler=scheduler, |
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) |
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self.vae_scale_factor = ( |
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2 ** (len(self.vae.config.block_out_channels)) if hasattr(self, "vae") and self.vae is not None else 16 |
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) |
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self.image_processor = VaeImageProcessor(vae_scale_factor=self.vae_scale_factor) |
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self.tokenizer_max_length = ( |
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self.tokenizer.model_max_length if hasattr(self, "tokenizer") and self.tokenizer is not None else 77 |
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) |
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self.default_sample_size = 64 |
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|
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def _get_t5_prompt_embeds( |
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self, |
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prompt: Union[str, List[str]] = None, |
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num_images_per_prompt: int = 1, |
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max_sequence_length: int = 512, |
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device: Optional[torch.device] = None, |
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dtype: Optional[torch.dtype] = None, |
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): |
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device = device or self._execution_device |
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dtype = dtype or self.text_encoder.dtype |
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|
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prompt = [prompt] if isinstance(prompt, str) else prompt |
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batch_size = len(prompt) |
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|
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text_inputs = self.tokenizer_2( |
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prompt, |
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padding="max_length", |
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max_length=max_sequence_length, |
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truncation=True, |
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return_length=True, |
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return_overflowing_tokens=True, |
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return_tensors="pt", |
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) |
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text_input_ids = text_inputs.input_ids |
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untruncated_ids = self.tokenizer_2(prompt, padding="longest", return_tensors="pt").input_ids |
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|
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if untruncated_ids.shape[-1] >= text_input_ids.shape[-1] and not torch.equal(text_input_ids, untruncated_ids): |
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removed_text = self.tokenizer_2.batch_decode(untruncated_ids[:, self.tokenizer_max_length - 1 : -1]) |
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logger.warning( |
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"The following part of your input was truncated because `max_sequence_length` is set to " |
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f" {max_sequence_length} tokens: {removed_text}" |
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) |
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|
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prompt_embeds = self.text_encoder_2(text_input_ids.to(device), output_hidden_states=False)[0] |
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|
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dtype = self.text_encoder_2.dtype |
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prompt_embeds = prompt_embeds.to(dtype=dtype, device=device) |
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|
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_, seq_len, _ = prompt_embeds.shape |
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|
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prompt_embeds = prompt_embeds.repeat(1, num_images_per_prompt, 1) |
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prompt_embeds = prompt_embeds.view(batch_size * num_images_per_prompt, seq_len, -1) |
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|
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return prompt_embeds |
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|
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def _get_clip_prompt_embeds( |
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self, |
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prompt: Union[str, List[str]], |
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num_images_per_prompt: int = 1, |
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device: Optional[torch.device] = None, |
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): |
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device = device or self._execution_device |
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|
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prompt = [prompt] if isinstance(prompt, str) else prompt |
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batch_size = len(prompt) |
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|
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text_inputs = self.tokenizer( |
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prompt, |
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padding="max_length", |
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max_length=self.tokenizer_max_length, |
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truncation=True, |
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return_overflowing_tokens=False, |
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return_length=False, |
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return_tensors="pt", |
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) |
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|
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text_input_ids = text_inputs.input_ids |
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untruncated_ids = self.tokenizer(prompt, padding="longest", return_tensors="pt").input_ids |
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if untruncated_ids.shape[-1] >= text_input_ids.shape[-1] and not torch.equal(text_input_ids, untruncated_ids): |
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removed_text = self.tokenizer.batch_decode(untruncated_ids[:, self.tokenizer_max_length - 1 : -1]) |
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logger.warning( |
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"The following part of your input was truncated because CLIP can only handle sequences up to" |
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f" {self.tokenizer_max_length} tokens: {removed_text}" |
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) |
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prompt_embeds = self.text_encoder(text_input_ids.to(device), output_hidden_states=False) |
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|
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|
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prompt_embeds = prompt_embeds.pooler_output |
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prompt_embeds = prompt_embeds.to(dtype=self.text_encoder.dtype, device=device) |
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|
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_, seq_len = prompt_embeds.shape |
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|
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prompt_embeds = prompt_embeds.repeat(1, num_images_per_prompt, 1) |
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prompt_embeds = prompt_embeds.view(batch_size * num_images_per_prompt, seq_len, -1) |
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|
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return prompt_embeds |
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|
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def encode_prompt( |
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self, |
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prompt: Union[str, List[str]], |
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prompt_2: Union[str, List[str]], |
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num_images_per_prompt: int = 1, |
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max_sequence_length: int = 512, |
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do_classifier_free_guidance: bool = True, |
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device: Optional[torch.device] = None, |
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negative_prompt: Optional[Union[str, List[str]]] = None, |
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negative_prompt_2: Optional[Union[str, List[str]]] = None, |
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prompt_embeds: Optional[torch.FloatTensor] = None, |
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negative_prompt_embeds: Optional[torch.Tensor] = None, |
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pooled_prompt_embeds: Optional[torch.FloatTensor] = None, |
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negative_pooled_prompt_embeds: Optional[torch.FloatTensor] = None, |
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lora_scale: Optional[float] = None, |
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): |
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device = device or self._execution_device |
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if device is None: |
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device = self._execution_device |
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|
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|
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if lora_scale is not None and isinstance(self, FluxLoraLoaderMixin): |
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self._lora_scale = lora_scale |
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|
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if self.text_encoder is not None and USE_PEFT_BACKEND: |
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scale_lora_layers(self.text_encoder, lora_scale) |
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if self.text_encoder_2 is not None and USE_PEFT_BACKEND: |
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scale_lora_layers(self.text_encoder_2, lora_scale) |
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|
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prompt = [prompt] if isinstance(prompt, str) else prompt |
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if prompt is not None: |
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batch_size = len(prompt) |
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else: |
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batch_size = prompt_embeds.shape[0] |
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|
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if prompt_embeds is None: |
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prompt_2 = prompt_2 or prompt |
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prompt_2 = [prompt_2] if isinstance(prompt_2, str) else prompt_2 |
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|
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pooled_prompt_embeds = self._get_clip_prompt_embeds( |
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prompt=prompt, |
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device=device, |
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num_images_per_prompt=num_images_per_prompt, |
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) |
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prompt_embeds = self._get_t5_prompt_embeds( |
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prompt=prompt_2, |
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num_images_per_prompt=num_images_per_prompt, |
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max_sequence_length=max_sequence_length, |
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device=device, |
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) |
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|
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if do_classifier_free_guidance and negative_prompt_embeds is None: |
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negative_prompt = negative_prompt or "" |
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negative_prompt_2 = negative_prompt_2 or negative_prompt |
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|
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negative_prompt = batch_size * [negative_prompt] if isinstance(negative_prompt, str) else negative_prompt |
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negative_prompt_2 = ( |
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batch_size * [negative_prompt_2] if isinstance(negative_prompt_2, str) else negative_prompt_2 |
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) |
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|
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if prompt is not None and type(prompt) is not type(negative_prompt): |
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raise TypeError( |
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f"`negative_prompt` should be the same type to `prompt`, but got {type(negative_prompt)} !=" |
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f" {type(prompt)}." |
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) |
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elif batch_size != len(negative_prompt): |
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raise ValueError( |
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f"`negative_prompt`: {negative_prompt} has batch size {len(negative_prompt)}, but `prompt`:" |
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f" {prompt} has batch size {batch_size}. Please make sure that passed `negative_prompt` matches" |
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" the batch size of `prompt`." |
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) |
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|
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negative_pooled_prompt_embeds = self._get_clip_prompt_embeds( |
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prompt=negative_prompt, |
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device=device, |
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num_images_per_prompt=num_images_per_prompt, |
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) |
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|
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negative_prompt_embeds = self._get_t5_prompt_embeds( |
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prompt=negative_prompt_2, |
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device=device, |
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num_images_per_prompt=num_images_per_prompt, |
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max_sequence_length=max_sequence_length, |
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) |
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|
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if self.text_encoder is not None: |
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if isinstance(self, FluxLoraLoaderMixin) and USE_PEFT_BACKEND: |
|
|
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unscale_lora_layers(self.text_encoder, lora_scale) |
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|
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if self.text_encoder_2 is not None: |
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if isinstance(self, FluxLoraLoaderMixin) and USE_PEFT_BACKEND: |
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|
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unscale_lora_layers(self.text_encoder_2, lora_scale) |
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|
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dtype = self.text_encoder.dtype if self.text_encoder is not None else self.transformer.dtype |
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text_ids = torch.zeros(prompt_embeds.shape[1], 3).to(device=device, dtype=dtype) |
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|
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return prompt_embeds, pooled_prompt_embeds, text_ids, negative_prompt_embeds, negative_pooled_prompt_embeds |
|
|
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def check_inputs( |
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self, |
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prompt, |
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prompt_2, |
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height, |
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width, |
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prompt_embeds=None, |
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negative_prompt_embeds=None, |
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pooled_prompt_embeds=None, |
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negative_pooled_prompt_embeds=None, |
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max_sequence_length=None, |
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): |
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if height % 8 != 0 or width % 8 != 0: |
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raise ValueError(f"`height` and `width` have to be divisible by 8 but are {height} and {width}.") |
|
|
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if prompt is not None and prompt_embeds is not None: |
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raise ValueError( |
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f"Cannot forward both `prompt`: {prompt} and `prompt_embeds`: {prompt_embeds}. Please make sure to" |
|
" only forward one of the two." |
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) |
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elif prompt_2 is not None and prompt_embeds is not None: |
|
raise ValueError( |
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f"Cannot forward both `prompt_2`: {prompt_2} and `prompt_embeds`: {prompt_embeds}. Please make sure to" |
|
" only forward one of the two." |
|
) |
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elif prompt is None and prompt_embeds is None: |
|
raise ValueError( |
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"Provide either `prompt` or `prompt_embeds`. Cannot leave both `prompt` and `prompt_embeds` undefined." |
|
) |
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elif prompt is not None and (not isinstance(prompt, str) and not isinstance(prompt, list)): |
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raise ValueError(f"`prompt` has to be of type `str` or `list` but is {type(prompt)}") |
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elif prompt_2 is not None and (not isinstance(prompt_2, str) and not isinstance(prompt_2, list)): |
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raise ValueError(f"`prompt_2` has to be of type `str` or `list` but is {type(prompt_2)}") |
|
|
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if prompt_embeds is not None and pooled_prompt_embeds is None: |
|
raise ValueError( |
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"If `prompt_embeds` are provided, `pooled_prompt_embeds` also have to be passed. Make sure to generate `pooled_prompt_embeds` from the same text encoder that was used to generate `prompt_embeds`." |
|
) |
|
if negative_prompt_embeds is not None and negative_pooled_prompt_embeds is None: |
|
raise ValueError("Must provide `negative_pooled_prompt_embeds` when specifying `negative_prompt_embeds`.") |
|
|
|
if max_sequence_length is not None and max_sequence_length > 512: |
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raise ValueError(f"`max_sequence_length` cannot be greater than 512 but is {max_sequence_length}") |
|
|
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@staticmethod |
|
def _prepare_latent_image_ids(batch_size, height, width, device, dtype): |
|
latent_image_ids = torch.zeros(height // 2, width // 2, 3) |
|
latent_image_ids[..., 1] = latent_image_ids[..., 1] + torch.arange(height // 2)[:, None] |
|
latent_image_ids[..., 2] = latent_image_ids[..., 2] + torch.arange(width // 2)[None, :] |
|
|
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latent_image_id_height, latent_image_id_width, latent_image_id_channels = latent_image_ids.shape |
|
|
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latent_image_ids = latent_image_ids[None, :].repeat(batch_size, 1, 1, 1) |
|
latent_image_ids = latent_image_ids.reshape( |
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batch_size, latent_image_id_height * latent_image_id_width, latent_image_id_channels |
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) |
|
|
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return latent_image_ids.to(device=device, dtype=dtype) |
|
|
|
@staticmethod |
|
def _pack_latents(latents, batch_size, num_channels_latents, height, width): |
|
latents = latents.view(batch_size, num_channels_latents, height // 2, 2, width // 2, 2) |
|
latents = latents.permute(0, 2, 4, 1, 3, 5) |
|
latents = latents.reshape(batch_size, (height // 2) * (width // 2), num_channels_latents * 4) |
|
|
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return latents |
|
|
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@staticmethod |
|
def _unpack_latents(latents, height, width, vae_scale_factor): |
|
batch_size, num_patches, channels = latents.shape |
|
|
|
height = height // vae_scale_factor |
|
width = width // vae_scale_factor |
|
|
|
latents = latents.view(batch_size, height, width, channels // 4, 2, 2) |
|
latents = latents.permute(0, 3, 1, 4, 2, 5) |
|
|
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latents = latents.reshape(batch_size, channels // (2 * 2), height * 2, width * 2) |
|
|
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return latents |
|
|
|
def prepare_latents( |
|
self, |
|
batch_size, |
|
num_channels_latents, |
|
height, |
|
width, |
|
dtype, |
|
device, |
|
generator, |
|
latents=None, |
|
): |
|
height = 2 * (int(height) // self.vae_scale_factor) |
|
width = 2 * (int(width) // self.vae_scale_factor) |
|
|
|
shape = (batch_size, num_channels_latents, height, width) |
|
|
|
if latents is not None: |
|
latent_image_ids = self._prepare_latent_image_ids(batch_size, height, width, device, dtype) |
|
return latents.to(device=device, dtype=dtype), latent_image_ids |
|
|
|
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." |
|
) |
|
|
|
latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype) |
|
latents = self._pack_latents(latents, batch_size, num_channels_latents, height, width) |
|
|
|
latent_image_ids = self._prepare_latent_image_ids(batch_size, height, width, device, dtype) |
|
|
|
return latents, latent_image_ids |
|
|
|
|
|
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 enable_vae_slicing(self): |
|
r""" |
|
Enable sliced VAE decoding. When this option is enabled, the VAE will split the input tensor in slices to |
|
compute decoding in several steps. This is useful to save some memory and allow larger batch sizes. |
|
""" |
|
self.vae.enable_slicing() |
|
|
|
def disable_vae_slicing(self): |
|
r""" |
|
Disable sliced VAE decoding. If `enable_vae_slicing` was previously enabled, this method will go back to |
|
computing decoding in one step. |
|
""" |
|
self.vae.disable_slicing() |
|
|
|
def enable_vae_tiling(self): |
|
r""" |
|
Enable tiled VAE decoding. When this option is enabled, the VAE will split the input tensor into tiles to |
|
compute decoding and encoding in several steps. This is useful for saving a large amount of memory and to allow |
|
processing larger images. |
|
""" |
|
self.vae.enable_tiling() |
|
|
|
def disable_vae_tiling(self): |
|
r""" |
|
Disable tiled VAE decoding. If `enable_vae_tiling` was previously enabled, this method will go back to |
|
computing decoding in one step. |
|
""" |
|
self.vae.disable_tiling() |
|
|
|
@property |
|
def guidance_scale(self): |
|
return self._guidance_scale |
|
|
|
@property |
|
def do_classifier_free_guidance(self): |
|
return self._guidance_scale > 1 |
|
|
|
@property |
|
def joint_attention_kwargs(self): |
|
return self._joint_attention_kwargs |
|
|
|
@property |
|
def num_timesteps(self): |
|
return self._num_timesteps |
|
|
|
@property |
|
def interrupt(self): |
|
return self._interrupt |
|
|
|
@torch.no_grad() |
|
@torch.inference_mode() |
|
def __call__( |
|
self, |
|
prompt: Union[str, List[str]] = None, |
|
prompt_2: Optional[Union[str, List[str]]] = None, |
|
negative_prompt: Union[str, List[str]] = None, |
|
height: Optional[int] = None, |
|
width: Optional[int] = None, |
|
num_inference_steps: int = 8, |
|
timesteps: List[int] = None, |
|
guidance_scale: float = 3.5, |
|
device: Optional[int] = None, |
|
num_images_per_prompt: Optional[int] = 1, |
|
generator: Optional[Union[torch.Generator, List[torch.Generator]]] = None, |
|
latents: Optional[torch.FloatTensor] = None, |
|
prompt_embeds: Optional[torch.FloatTensor] = None, |
|
pooled_prompt_embeds: Optional[torch.FloatTensor] = None, |
|
output_type: Optional[str] = "pil", |
|
cfg: Optional[bool] = True, |
|
return_dict: bool = True, |
|
joint_attention_kwargs: Optional[Dict[str, Any]] = None, |
|
max_sequence_length: int = 512, |
|
): |
|
height = height or self.default_sample_size * self.vae_scale_factor |
|
width = width or self.default_sample_size * self.vae_scale_factor |
|
|
|
|
|
self.check_inputs( |
|
prompt, |
|
prompt_2, |
|
height, |
|
width, |
|
prompt_embeds=prompt_embeds, |
|
pooled_prompt_embeds=pooled_prompt_embeds, |
|
max_sequence_length=max_sequence_length, |
|
) |
|
|
|
self._guidance_scale = guidance_scale |
|
self._joint_attention_kwargs = joint_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 = torch.device("cuda:0" if torch.cuda.is_available() else "cpu") |
|
|
|
lora_scale = ( |
|
self.joint_attention_kwargs.get("scale", None) if self.joint_attention_kwargs is not None else None |
|
) |
|
( |
|
prompt_embeds, |
|
pooled_prompt_embeds, |
|
text_ids, |
|
negative_prompt_embeds, |
|
negative_pooled_prompt_embeds |
|
) = self.encode_prompt( |
|
prompt=prompt, |
|
prompt_2=prompt_2, |
|
num_images_per_prompt=num_images_per_prompt, |
|
max_sequence_length=max_sequence_length, |
|
device=device, |
|
negative_prompt=negative_prompt, |
|
prompt_embeds=prompt_embeds, |
|
pooled_prompt_embeds=pooled_prompt_embeds, |
|
lora_scale=lora_scale, |
|
) |
|
|
|
if self.do_classifier_free_guidance: |
|
prompt_embeds = torch.cat([negative_prompt_embeds, prompt_embeds], dim=0) |
|
pooled_prompt_embeds = torch.cat([negative_pooled_prompt_embeds, pooled_prompt_embeds], dim=0) |
|
|
|
|
|
num_channels_latents = self.transformer.config.in_channels // 4 |
|
latents, latent_image_ids = self.prepare_latents( |
|
batch_size * num_images_per_prompt, |
|
num_channels_latents, |
|
height, |
|
width, |
|
prompt_embeds.dtype, |
|
device, |
|
generator, |
|
latents, |
|
) |
|
|
|
|
|
sigmas = np.linspace(1.0, 1 / num_inference_steps, num_inference_steps) |
|
image_seq_len = latents.shape[1] |
|
mu = calculate_shift( |
|
image_seq_len, |
|
self.scheduler.config.base_image_seq_len, |
|
self.scheduler.config.max_image_seq_len, |
|
self.scheduler.config.base_shift, |
|
self.scheduler.config.max_shift, |
|
) |
|
timesteps, num_inference_steps = prepare_timesteps( |
|
self.scheduler, |
|
num_inference_steps, |
|
device, |
|
timesteps, |
|
sigmas, |
|
mu=mu, |
|
) |
|
num_warmup_steps = max(len(timesteps) - num_inference_steps * self.scheduler.order, 0) |
|
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 |
|
|
|
timestep = t.expand(latent_model_input.shape[0]) |
|
|
|
noise_pred = self.transformer( |
|
hidden_states=latent_model_input, |
|
timestep=timestep / 1000, |
|
pooled_projections=pooled_prompt_embeds, |
|
encoder_hidden_states=prompt_embeds, |
|
txt_ids=text_ids, |
|
img_ids=latent_image_ids, |
|
joint_attention_kwargs=self.joint_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) |
|
|
|
|
|
latents_dtype = latents.dtype |
|
latents = self.scheduler.step(noise_pred, t, latents, return_dict=False)[0] |
|
|
|
if latents.dtype != latents_dtype: |
|
if torch.backends.mps.is_available(): |
|
|
|
latents = latents.to(latents_dtype) |
|
|
|
|
|
if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0): |
|
progress_bar.update() |
|
|
|
|
|
return self._decode_latents_to_image(latents, height, width, output_type) |
|
self.maybe_free_model_hooks() |
|
torch.cuda.empty_cache() |
|
|
|
def _decode_latents_to_image(self, latents, height, width, output_type, vae=None): |
|
"""Decodes the given latents into an image.""" |
|
vae = vae or self.vae |
|
latents = self._unpack_latents(latents, height, width, self.vae_scale_factor) |
|
latents = (latents / vae.config.scaling_factor) + vae.config.shift_factor |
|
image = vae.decode(latents, return_dict=False)[0] |
|
return self.image_processor.postprocess(image, output_type=output_type)[0] |