import inspect from typing import Any, Callable, Dict, List, Optional, Union import numpy as np import torch from transformers import CLIPTextModel, CLIPTokenizer, T5EncoderModel, T5TokenizerFast from diffusers.image_processor import (VaeImageProcessor) from diffusers.loaders import FluxLoraLoaderMixin, FromSingleFileMixin from diffusers.models.autoencoders import AutoencoderKL from diffusers.schedulers import FlowMatchEulerDiscreteScheduler from diffusers.utils import ( USE_PEFT_BACKEND, is_torch_xla_available, logging, scale_lora_layers, unscale_lora_layers, ) from diffusers.utils.torch_utils import randn_tensor from diffusers.pipelines.pipeline_utils import DiffusionPipeline from diffusers.pipelines.flux.pipeline_output import FluxPipelineOutput from torchvision.transforms.functional import pad from .transformer_flux import FluxTransformer2DModel if is_torch_xla_available(): import torch_xla.core.xla_model as xm XLA_AVAILABLE = True else: XLA_AVAILABLE = False logger = logging.get_logger(__name__) # pylint: disable=invalid-name def calculate_shift( image_seq_len, base_seq_len: int = 256, max_seq_len: int = 4096, base_shift: float = 0.5, max_shift: float = 1.16, ): m = (max_shift - base_shift) / (max_seq_len - base_seq_len) b = base_shift - m * base_seq_len mu = image_seq_len * m + b return mu def prepare_latent_image_ids_(height, width, device, dtype): latent_image_ids = torch.zeros(height//2, width//2, 3, device=device, dtype=dtype) latent_image_ids[..., 1] = latent_image_ids[..., 1] + torch.arange(height//2, device=device)[:, None] # y latent_image_ids[..., 2] = latent_image_ids[..., 2] + torch.arange(width//2, device=device)[None, :] # x return latent_image_ids def prepare_latent_subject_ids(height, width, device, dtype): latent_image_ids = torch.zeros(height // 2, width // 2, 3, device=device, dtype=dtype) latent_image_ids[..., 1] = latent_image_ids[..., 1] + torch.arange(height // 2, device=device)[:, None] latent_image_ids[..., 2] = latent_image_ids[..., 2] + torch.arange(width // 2, device=device)[None, :] latent_image_id_height, latent_image_id_width, latent_image_id_channels = latent_image_ids.shape latent_image_ids = latent_image_ids.reshape( latent_image_id_height * latent_image_id_width, latent_image_id_channels ) return latent_image_ids.to(device=device, dtype=dtype) def resize_position_encoding(batch_size, original_height, original_width, target_height, target_width, device, dtype): latent_image_ids = prepare_latent_image_ids_(original_height, original_width, device, dtype) latent_image_id_height, latent_image_id_width, latent_image_id_channels = latent_image_ids.shape latent_image_ids = latent_image_ids.reshape( latent_image_id_height * latent_image_id_width, latent_image_id_channels ) scale_h = original_height / target_height scale_w = original_width / target_width latent_image_ids_resized = torch.zeros(target_height//2, target_width//2, 3, device=device, dtype=dtype) latent_image_ids_resized[..., 1] = latent_image_ids_resized[..., 1] + torch.arange(target_height//2, device=device)[:, None] * scale_h latent_image_ids_resized[..., 2] = latent_image_ids_resized[..., 2] + torch.arange(target_width//2, device=device)[None, :] * scale_w cond_latent_image_id_height, cond_latent_image_id_width, cond_latent_image_id_channels = latent_image_ids_resized.shape cond_latent_image_ids = latent_image_ids_resized.reshape( cond_latent_image_id_height * cond_latent_image_id_width, cond_latent_image_id_channels ) return latent_image_ids, cond_latent_image_ids # Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion_img2img.retrieve_latents def retrieve_latents( encoder_output: torch.Tensor, generator: Optional[torch.Generator] = None, sample_mode: str = "sample" ): if hasattr(encoder_output, "latent_dist") and sample_mode == "sample": return encoder_output.latent_dist.sample(generator) elif hasattr(encoder_output, "latent_dist") and sample_mode == "argmax": return encoder_output.latent_dist.mode() elif hasattr(encoder_output, "latents"): return encoder_output.latents else: raise AttributeError("Could not access latents of provided encoder_output") # Copied from diffusers.pipelines.stable_diffusion.pipeline_stable_diffusion.retrieve_timesteps def retrieve_timesteps( scheduler, num_inference_steps: Optional[int] = None, device: Optional[Union[str, torch.device]] = None, timesteps: Optional[List[int]] = None, sigmas: Optional[List[float]] = None, **kwargs, ): if timesteps is not None and sigmas is not None: raise ValueError("Only one of `timesteps` or `sigmas` can be passed. Please choose one to set custom values") 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) elif sigmas is not None: accept_sigmas = "sigmas" in set(inspect.signature(scheduler.set_timesteps).parameters.keys()) if not accept_sigmas: raise ValueError( f"The current scheduler class {scheduler.__class__}'s `set_timesteps` does not support custom" f" sigmas schedules. Please check whether you are using the correct scheduler." ) scheduler.set_timesteps(sigmas=sigmas, 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 FluxPipeline(DiffusionPipeline, FluxLoraLoaderMixin, FromSingleFileMixin): def __init__( self, scheduler: FlowMatchEulerDiscreteScheduler, vae: AutoencoderKL, text_encoder: CLIPTextModel, tokenizer: CLIPTokenizer, text_encoder_2: T5EncoderModel, tokenizer_2: T5TokenizerFast, transformer: FluxTransformer2DModel, ): super().__init__() self.register_modules( vae=vae, text_encoder=text_encoder, text_encoder_2=text_encoder_2, tokenizer=tokenizer, tokenizer_2=tokenizer_2, transformer=transformer, scheduler=scheduler, ) self.vae_scale_factor = ( 2 ** (len(self.vae.config.block_out_channels)) if hasattr(self, "vae") and self.vae is not None else 16 ) self.image_processor = VaeImageProcessor(vae_scale_factor=self.vae_scale_factor) self.tokenizer_max_length = ( self.tokenizer.model_max_length if hasattr(self, "tokenizer") and self.tokenizer is not None else 77 ) self.default_sample_size = 64 def _get_t5_prompt_embeds( self, prompt: Union[str, List[str]] = None, num_images_per_prompt: int = 1, max_sequence_length: int = 512, device: Optional[torch.device] = None, dtype: Optional[torch.dtype] = None, ): device = device or self._execution_device dtype = dtype or self.text_encoder.dtype prompt = [prompt] if isinstance(prompt, str) else prompt batch_size = len(prompt) text_inputs = self.tokenizer_2( prompt, padding="max_length", max_length=max_sequence_length, truncation=True, return_length=False, return_overflowing_tokens=False, return_tensors="pt", ) text_input_ids = text_inputs.input_ids untruncated_ids = self.tokenizer_2(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_2.batch_decode(untruncated_ids[:, self.tokenizer_max_length - 1: -1]) logger.warning( "The following part of your input was truncated because `max_sequence_length` is set to " f" {max_sequence_length} tokens: {removed_text}" ) prompt_embeds = self.text_encoder_2(text_input_ids.to(device), output_hidden_states=False)[0] dtype = self.text_encoder_2.dtype prompt_embeds = prompt_embeds.to(dtype=dtype, device=device) _, seq_len, _ = prompt_embeds.shape # duplicate text embeddings and attention mask for each generation per prompt, using mps friendly method prompt_embeds = prompt_embeds.repeat(1, num_images_per_prompt, 1) prompt_embeds = prompt_embeds.view(batch_size * num_images_per_prompt, seq_len, -1) return prompt_embeds def _get_clip_prompt_embeds( self, prompt: Union[str, List[str]], num_images_per_prompt: int = 1, device: Optional[torch.device] = None, ): device = device or self._execution_device prompt = [prompt] if isinstance(prompt, str) else prompt batch_size = len(prompt) text_inputs = self.tokenizer( prompt, padding="max_length", max_length=self.tokenizer_max_length, truncation=True, return_overflowing_tokens=False, return_length=False, 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_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_max_length} tokens: {removed_text}" ) prompt_embeds = self.text_encoder(text_input_ids.to(device), output_hidden_states=False) # Use pooled output of CLIPTextModel prompt_embeds = prompt_embeds.pooler_output prompt_embeds = prompt_embeds.to(dtype=self.text_encoder.dtype, device=device) # duplicate text embeddings for each generation per prompt, using mps friendly method prompt_embeds = prompt_embeds.repeat(1, num_images_per_prompt) prompt_embeds = prompt_embeds.view(batch_size * num_images_per_prompt, -1) return prompt_embeds def encode_prompt( self, prompt: Union[str, List[str]], prompt_2: Union[str, List[str]], device: Optional[torch.device] = None, num_images_per_prompt: int = 1, prompt_embeds: Optional[torch.FloatTensor] = None, pooled_prompt_embeds: Optional[torch.FloatTensor] = None, max_sequence_length: int = 512, lora_scale: Optional[float] = None, ): device = device or self._execution_device # set lora scale so that monkey patched LoRA # function of text encoder can correctly access it if lora_scale is not None and isinstance(self, FluxLoraLoaderMixin): self._lora_scale = lora_scale # dynamically adjust the LoRA scale if self.text_encoder is not None and USE_PEFT_BACKEND: scale_lora_layers(self.text_encoder, lora_scale) if self.text_encoder_2 is not None and USE_PEFT_BACKEND: scale_lora_layers(self.text_encoder_2, lora_scale) prompt = [prompt] if isinstance(prompt, str) else prompt if prompt_embeds is None: prompt_2 = prompt_2 or prompt prompt_2 = [prompt_2] if isinstance(prompt_2, str) else prompt_2 # We only use the pooled prompt output from the CLIPTextModel pooled_prompt_embeds = self._get_clip_prompt_embeds( prompt=prompt, device=device, num_images_per_prompt=num_images_per_prompt, ) prompt_embeds = self._get_t5_prompt_embeds( prompt=prompt_2, num_images_per_prompt=num_images_per_prompt, max_sequence_length=max_sequence_length, device=device, ) if self.text_encoder is not None: if isinstance(self, FluxLoraLoaderMixin) and USE_PEFT_BACKEND: # Retrieve the original scale by scaling back the LoRA layers unscale_lora_layers(self.text_encoder, lora_scale) if self.text_encoder_2 is not None: if isinstance(self, FluxLoraLoaderMixin) and USE_PEFT_BACKEND: # Retrieve the original scale by scaling back the LoRA layers unscale_lora_layers(self.text_encoder_2, lora_scale) dtype = self.text_encoder.dtype if self.text_encoder is not None else self.transformer.dtype text_ids = torch.zeros(prompt_embeds.shape[1], 3).to(device=device, dtype=dtype) return prompt_embeds, pooled_prompt_embeds, text_ids # Copied from diffusers.pipelines.stable_diffusion_3.pipeline_stable_diffusion_3_inpaint.StableDiffusion3InpaintPipeline._encode_vae_image def _encode_vae_image(self, image: torch.Tensor, generator: torch.Generator): if isinstance(generator, list): image_latents = [ retrieve_latents(self.vae.encode(image[i: i + 1]), generator=generator[i]) for i in range(image.shape[0]) ] image_latents = torch.cat(image_latents, dim=0) else: image_latents = retrieve_latents(self.vae.encode(image), generator=generator) image_latents = (image_latents - self.vae.config.shift_factor) * self.vae.config.scaling_factor return image_latents def check_inputs( self, prompt, prompt_2, height, width, prompt_embeds=None, pooled_prompt_embeds=None, callback_on_step_end_tensor_inputs=None, max_sequence_length=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_2 is not None and prompt_embeds is not None: raise ValueError( f"Cannot forward both `prompt_2`: {prompt_2} 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)}") elif prompt_2 is not None and (not isinstance(prompt_2, str) and not isinstance(prompt_2, list)): raise ValueError(f"`prompt_2` has to be of type `str` or `list` but is {type(prompt_2)}") if prompt_embeds is not None and pooled_prompt_embeds is None: raise ValueError( "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 max_sequence_length is not None and max_sequence_length > 512: raise ValueError(f"`max_sequence_length` cannot be greater than 512 but is {max_sequence_length}") @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, :] latent_image_id_height, latent_image_id_width, latent_image_id_channels = latent_image_ids.shape latent_image_ids = latent_image_ids.reshape( latent_image_id_height * latent_image_id_width, latent_image_id_channels ) 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) return latents @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) latents = latents.reshape(batch_size, channels // (2 * 2), height * 2, width * 2) return latents 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() def prepare_latents( self, batch_size, num_channels_latents, height, width, dtype, device, generator, subject_image, condition_image, latents=None, cond_number=1, sub_number=1 ): height_cond = 2 * (self.cond_size // self.vae_scale_factor) width_cond = 2 * (self.cond_size // self.vae_scale_factor) height = 2 * (int(height) // self.vae_scale_factor) width = 2 * (int(width) // self.vae_scale_factor) shape = (batch_size, num_channels_latents, height, width) # 1 16 106 80 noise_latents = randn_tensor(shape, generator=generator, device=device, dtype=dtype) noise_latents = self._pack_latents(noise_latents, batch_size, num_channels_latents, height, width) noise_latent_image_ids, cond_latent_image_ids = resize_position_encoding( batch_size, height, width, height_cond, width_cond, device, dtype, ) latents_to_concat = [] latents_ids_to_concat = [noise_latent_image_ids] # subject if subject_image is not None: shape_subject = (batch_size, num_channels_latents, height_cond*sub_number, width_cond) subject_image = subject_image.to(device=device, dtype=dtype) subject_image_latents = self._encode_vae_image(image=subject_image, generator=generator) subject_latents = self._pack_latents(subject_image_latents, batch_size, num_channels_latents, height_cond*sub_number, width_cond) mask2 = torch.zeros(shape_subject, device=device, dtype=dtype) mask2 = self._pack_latents(mask2, batch_size, num_channels_latents, height_cond*sub_number, width_cond) latent_subject_ids = prepare_latent_subject_ids(height_cond, width_cond, device, dtype) latent_subject_ids[:, 1] += 64 # fixed offset subject_latent_image_ids = torch.concat([latent_subject_ids for _ in range(sub_number)], dim=-2) latents_to_concat.append(subject_latents) latents_ids_to_concat.append(subject_latent_image_ids) # spatial if condition_image is not None: shape_cond = (batch_size, num_channels_latents, height_cond*cond_number, width_cond) condition_image = condition_image.to(device=device, dtype=dtype) image_latents = self._encode_vae_image(image=condition_image, generator=generator) cond_latents = self._pack_latents(image_latents, batch_size, num_channels_latents, height_cond*cond_number, width_cond) mask3 = torch.zeros(shape_cond, device=device, dtype=dtype) mask3 = self._pack_latents(mask3, batch_size, num_channels_latents, height_cond*cond_number, width_cond) cond_latent_image_ids = cond_latent_image_ids cond_latent_image_ids = torch.concat([cond_latent_image_ids for _ in range(cond_number)], dim=-2) latents_ids_to_concat.append(cond_latent_image_ids) latents_to_concat.append(cond_latents) cond_latents = torch.concat(latents_to_concat, dim=-2) latent_image_ids = torch.concat(latents_ids_to_concat, dim=-2) return cond_latents, latent_image_ids, noise_latents @property def guidance_scale(self): return self._guidance_scale @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() def __call__( self, prompt: Union[str, List[str]] = None, prompt_2: Optional[Union[str, List[str]]] = None, height: Optional[int] = None, width: Optional[int] = None, num_inference_steps: int = 28, timesteps: List[int] = None, guidance_scale: float = 3.5, 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", return_dict: bool = True, joint_attention_kwargs: Optional[Dict[str, Any]] = None, callback_on_step_end: Optional[Callable[[int, int, Dict], None]] = None, callback_on_step_end_tensor_inputs: List[str] = ["latents"], max_sequence_length: int = 512, spatial_images=None, subject_images=None, cond_size=512, ): height = height or self.default_sample_size * self.vae_scale_factor width = width or self.default_sample_size * self.vae_scale_factor self.cond_size = cond_size # 1. Check inputs. Raise error if not correct self.check_inputs( prompt, prompt_2, height, width, prompt_embeds=prompt_embeds, pooled_prompt_embeds=pooled_prompt_embeds, callback_on_step_end_tensor_inputs=callback_on_step_end_tensor_inputs, max_sequence_length=max_sequence_length, ) self._guidance_scale = guidance_scale self._joint_attention_kwargs = joint_attention_kwargs self._interrupt = False cond_number = len(spatial_images) sub_number = len(subject_images) if sub_number > 0: subject_image_ls = [] for subject_image in subject_images: w, h = subject_image.size[:2] scale = self.cond_size / max(h, w) new_h, new_w = int(h * scale), int(w * scale) subject_image = self.image_processor.preprocess(subject_image, height=new_h, width=new_w) subject_image = subject_image.to(dtype=torch.float32) pad_h = cond_size - subject_image.shape[-2] pad_w = cond_size - subject_image.shape[-1] subject_image = pad( subject_image, padding=(int(pad_w / 2), int(pad_h / 2), int(pad_w / 2), int(pad_h / 2)), fill=0 ) subject_image_ls.append(subject_image) subject_image = torch.concat(subject_image_ls, dim=-2) else: subject_image = None if cond_number > 0: condition_image_ls = [] for img in spatial_images: condition_image = self.image_processor.preprocess(img, height=self.cond_size, width=self.cond_size) condition_image = condition_image.to(dtype=torch.float32) condition_image_ls.append(condition_image) condition_image = torch.concat(condition_image_ls, dim=-2) else: condition_image = None # 2. Define call parameters 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.joint_attention_kwargs.get("scale", None) if self.joint_attention_kwargs is not None else None ) ( prompt_embeds, pooled_prompt_embeds, text_ids, ) = self.encode_prompt( prompt=prompt, prompt_2=prompt_2, prompt_embeds=prompt_embeds, pooled_prompt_embeds=pooled_prompt_embeds, device=device, num_images_per_prompt=num_images_per_prompt, max_sequence_length=max_sequence_length, lora_scale=lora_scale, ) # 4. Prepare latent variables num_channels_latents = self.transformer.config.in_channels // 4 # 16 cond_latents, latent_image_ids, noise_latents = self.prepare_latents( batch_size * num_images_per_prompt, num_channels_latents, height, width, prompt_embeds.dtype, device, generator, subject_image, condition_image, latents, cond_number, sub_number ) latents = noise_latents # 5. Prepare timesteps 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 = retrieve_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) # handle guidance if self.transformer.config.guidance_embeds: guidance = torch.full([1], guidance_scale, device=device, dtype=torch.float32) guidance = guidance.expand(latents.shape[0]) else: guidance = None ## Caching conditions # clean the cache for name, attn_processor in self.transformer.attn_processors.items(): attn_processor.bank_kv.clear() # cache with warmup latents start_idx = latents.shape[1] - 32 warmup_latents = latents[:, start_idx:, :] warmup_latent_ids = latent_image_ids[start_idx:, :] t = torch.tensor([timesteps[0]], device=device) timestep = t.expand(warmup_latents.shape[0]).to(latents.dtype) _ = self.transformer( hidden_states=warmup_latents, cond_hidden_states=cond_latents, timestep=timestep/ 1000, guidance=guidance, pooled_projections=pooled_prompt_embeds, encoder_hidden_states=prompt_embeds, txt_ids=text_ids, img_ids=warmup_latent_ids, joint_attention_kwargs=self.joint_attention_kwargs, return_dict=False, )[0] # 6. Denoising loop with self.progress_bar(total=num_inference_steps) as progress_bar: for i, t in enumerate(timesteps): if self.interrupt: continue # broadcast to batch dimension in a way that's compatible with ONNX/Core ML timestep = t.expand(latents.shape[0]).to(latents.dtype) noise_pred = self.transformer( hidden_states=latents, cond_hidden_states=cond_latents, timestep=timestep / 1000, guidance=guidance, 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] # compute the previous noisy sample x_t -> x_t-1 latents_dtype = latents.dtype latents = self.scheduler.step(noise_pred, t, latents, return_dict=False)[0] latents = latents if latents.dtype != latents_dtype: if torch.backends.mps.is_available(): # some platforms (eg. apple mps) misbehave due to a pytorch bug: https://github.com/pytorch/pytorch/pull/99272 latents = latents.to(latents_dtype) if callback_on_step_end is not None: callback_kwargs = {} for k in callback_on_step_end_tensor_inputs: callback_kwargs[k] = locals()[k] callback_outputs = callback_on_step_end(self, i, t, callback_kwargs) latents = callback_outputs.pop("latents", latents) prompt_embeds = callback_outputs.pop("prompt_embeds", prompt_embeds) # call the callback, if provided if i == len(timesteps) - 1 or ((i + 1) > num_warmup_steps and (i + 1) % self.scheduler.order == 0): progress_bar.update() if XLA_AVAILABLE: xm.mark_step() if output_type == "latent": image = latents else: latents = self._unpack_latents(latents, height, width, self.vae_scale_factor) latents = (latents / self.vae.config.scaling_factor) + self.vae.config.shift_factor image = self.vae.decode(latents.to(dtype=self.vae.dtype), return_dict=False)[0] image = self.image_processor.postprocess(image, output_type=output_type) # Offload all models self.maybe_free_model_hooks() if not return_dict: return (image,) return FluxPipelineOutput(images=image)