# Copyright 2024 The HuggingFace Team. All rights reserved. # # Licensed under the Apache License, Version 2.0 (the "License"); # you may not use this file except in compliance with the License. # You may obtain a copy of the License at # # http://www.apache.org/licenses/LICENSE-2.0 # # Unless required by applicable law or agreed to in writing, software # distributed under the License is distributed on an "AS IS" BASIS, # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. # See the License for the specific language governing permissions and # limitations under the License. from typing import Any, Dict, Optional, Tuple, Union import torch import torch.utils.checkpoint from diffusers.models.unet_2d_condition import UNet2DConditionOutput from diffusers.utils import ( USE_PEFT_BACKEND, deprecate, logging, scale_lora_layers, unscale_lora_layers, ) logger = logging.get_logger(__name__) # pylint: disable=invalid-name def UNet2DConditionModel_forward( self, sample: torch.FloatTensor, timestep: Union[torch.Tensor, float, int], encoder_hidden_states: torch.Tensor, class_labels: Optional[torch.Tensor] = None, timestep_cond: Optional[torch.Tensor] = None, attention_mask: Optional[torch.Tensor] = None, cross_attention_kwargs: Optional[Dict[str, Any]] = None, added_cond_kwargs: Optional[Dict[str, torch.Tensor]] = None, down_block_additional_residuals: Optional[Tuple[torch.Tensor]] = None, mid_block_additional_residual: Optional[torch.Tensor] = None, down_intrablock_additional_residuals: Optional[Tuple[torch.Tensor]] = None, encoder_attention_mask: Optional[torch.Tensor] = None, return_dict: bool = True, down_block_add_samples: Optional[Tuple[torch.Tensor]] = None, mid_block_add_sample: Optional[Tuple[torch.Tensor]] = None, up_block_add_samples: Optional[Tuple[torch.Tensor]] = None, ) -> Union[UNet2DConditionOutput, Tuple]: r""" The [`UNet2DConditionModel`] forward method. Args: sample (`torch.FloatTensor`): The noisy input tensor with the following shape `(batch, channel, height, width)`. timestep (`torch.FloatTensor` or `float` or `int`): The number of timesteps to denoise an input. encoder_hidden_states (`torch.FloatTensor`): The encoder hidden states with shape `(batch, sequence_length, feature_dim)`. class_labels (`torch.Tensor`, *optional*, defaults to `None`): Optional class labels for conditioning. Their embeddings will be summed with the timestep embeddings. timestep_cond: (`torch.Tensor`, *optional*, defaults to `None`): Conditional embeddings for timestep. If provided, the embeddings will be summed with the samples passed through the `self.time_embedding` layer to obtain the timestep embeddings. attention_mask (`torch.Tensor`, *optional*, defaults to `None`): An attention mask of shape `(batch, key_tokens)` is applied to `encoder_hidden_states`. If `1` the mask is kept, otherwise if `0` it is discarded. Mask will be converted into a bias, which adds large negative values to the attention scores corresponding to "discard" tokens. cross_attention_kwargs (`dict`, *optional*): A kwargs dictionary that if specified is passed along to the `AttentionProcessor` as defined under `self.processor` in [diffusers.models.attention_processor](https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/attention_processor.py). added_cond_kwargs: (`dict`, *optional*): A kwargs dictionary containing additional embeddings that if specified are added to the embeddings that are passed along to the UNet blocks. down_block_additional_residuals: (`tuple` of `torch.Tensor`, *optional*): A tuple of tensors that if specified are added to the residuals of down unet blocks. mid_block_additional_residual: (`torch.Tensor`, *optional*): A tensor that if specified is added to the residual of the middle unet block. encoder_attention_mask (`torch.Tensor`): A cross-attention mask of shape `(batch, sequence_length)` is applied to `encoder_hidden_states`. If `True` the mask is kept, otherwise if `False` it is discarded. Mask will be converted into a bias, which adds large negative values to the attention scores corresponding to "discard" tokens. return_dict (`bool`, *optional*, defaults to `True`): Whether or not to return a [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] instead of a plain tuple. cross_attention_kwargs (`dict`, *optional*): A kwargs dictionary that if specified is passed along to the [`AttnProcessor`]. added_cond_kwargs: (`dict`, *optional*): A kwargs dictionary containin additional embeddings that if specified are added to the embeddings that are passed along to the UNet blocks. down_block_additional_residuals (`tuple` of `torch.Tensor`, *optional*): additional residuals to be added to UNet long skip connections from down blocks to up blocks for example from ControlNet side model(s) mid_block_additional_residual (`torch.Tensor`, *optional*): additional residual to be added to UNet mid block output, for example from ControlNet side model down_intrablock_additional_residuals (`tuple` of `torch.Tensor`, *optional*): additional residuals to be added within UNet down blocks, for example from T2I-Adapter side model(s) Returns: [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] or `tuple`: If `return_dict` is True, an [`~models.unets.unet_2d_condition.UNet2DConditionOutput`] is returned, otherwise a `tuple` is returned where the first element is the sample tensor. """ # By default samples have to be AT least a multiple of the overall upsampling factor. # The overall upsampling factor is equal to 2 ** (# num of upsampling layers). # However, the upsampling interpolation output size can be forced to fit any upsampling size # on the fly if necessary. default_overall_up_factor = 2**self.num_upsamplers # upsample size should be forwarded when sample is not a multiple of `default_overall_up_factor` forward_upsample_size = False upsample_size = None for dim in sample.shape[-2:]: if dim % default_overall_up_factor != 0: # Forward upsample size to force interpolation output size. forward_upsample_size = True break # ensure attention_mask is a bias, and give it a singleton query_tokens dimension # expects mask of shape: # [batch, key_tokens] # adds singleton query_tokens dimension: # [batch, 1, key_tokens] # this helps to broadcast it as a bias over attention scores, which will be in one of the following shapes: # [batch, heads, query_tokens, key_tokens] (e.g. torch sdp attn) # [batch * heads, query_tokens, key_tokens] (e.g. xformers or classic attn) if attention_mask is not None: # assume that mask is expressed as: # (1 = keep, 0 = discard) # convert mask into a bias that can be added to attention scores: # (keep = +0, discard = -10000.0) attention_mask = (1 - attention_mask.to(sample.dtype)) * -10000.0 attention_mask = attention_mask.unsqueeze(1) # convert encoder_attention_mask to a bias the same way we do for attention_mask if encoder_attention_mask is not None: encoder_attention_mask = ( 1 - encoder_attention_mask.to(sample.dtype) ) * -10000.0 encoder_attention_mask = encoder_attention_mask.unsqueeze(1) # 0. center input if necessary if self.config.center_input_sample: sample = 2 * sample - 1.0 # 1. time t_emb = self.get_time_embed(sample=sample, timestep=timestep) emb = self.time_embedding(t_emb, timestep_cond) aug_emb = None class_emb = self.get_class_embed(sample=sample, class_labels=class_labels) if class_emb is not None: if self.config.class_embeddings_concat: emb = torch.cat([emb, class_emb], dim=-1) else: emb = emb + class_emb aug_emb = self.get_aug_embed( emb=emb, encoder_hidden_states=encoder_hidden_states, added_cond_kwargs=added_cond_kwargs, ) if self.config.addition_embed_type == "image_hint": aug_emb, hint = aug_emb sample = torch.cat([sample, hint], dim=1) emb = emb + aug_emb if aug_emb is not None else emb if self.time_embed_act is not None: emb = self.time_embed_act(emb) encoder_hidden_states = self.process_encoder_hidden_states( encoder_hidden_states=encoder_hidden_states, added_cond_kwargs=added_cond_kwargs, ) # 2. pre-process sample = self.conv_in(sample) # 2.5 GLIGEN position net if ( cross_attention_kwargs is not None and cross_attention_kwargs.get("gligen", None) is not None ): cross_attention_kwargs = cross_attention_kwargs.copy() gligen_args = cross_attention_kwargs.pop("gligen") cross_attention_kwargs["gligen"] = {"objs": self.position_net(**gligen_args)} # 3. down lora_scale = ( cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0 ) if USE_PEFT_BACKEND: # weight the lora layers by setting `lora_scale` for each PEFT layer scale_lora_layers(self, lora_scale) is_controlnet = ( mid_block_additional_residual is not None and down_block_additional_residuals is not None ) # using new arg down_intrablock_additional_residuals for T2I-Adapters, to distinguish from controlnets is_adapter = down_intrablock_additional_residuals is not None # maintain backward compatibility for legacy usage, where # T2I-Adapter and ControlNet both use down_block_additional_residuals arg # but can only use one or the other is_brushnet = ( down_block_add_samples is not None and mid_block_add_sample is not None and up_block_add_samples is not None ) if ( not is_adapter and mid_block_additional_residual is None and down_block_additional_residuals is not None ): deprecate( "T2I should not use down_block_additional_residuals", "1.3.0", "Passing intrablock residual connections with `down_block_additional_residuals` is deprecated \ and will be removed in diffusers 1.3.0. `down_block_additional_residuals` should only be used \ for ControlNet. Please make sure use `down_intrablock_additional_residuals` instead. ", standard_warn=False, ) down_intrablock_additional_residuals = down_block_additional_residuals is_adapter = True down_block_res_samples = (sample,) if is_brushnet: sample = sample + down_block_add_samples.pop(0) for downsample_block in self.down_blocks: if ( hasattr(downsample_block, "has_cross_attention") and downsample_block.has_cross_attention ): # For t2i-adapter CrossAttnDownBlock2D additional_residuals = {} if is_adapter and len(down_intrablock_additional_residuals) > 0: additional_residuals["additional_residuals"] = ( down_intrablock_additional_residuals.pop(0) ) if is_brushnet and len(down_block_add_samples) > 0: additional_residuals["down_block_add_samples"] = [ down_block_add_samples.pop(0) for _ in range( len(downsample_block.resnets) + (downsample_block.downsamplers != None) ) ] sample, res_samples = downsample_block( hidden_states=sample, temb=emb, encoder_hidden_states=encoder_hidden_states, attention_mask=attention_mask, cross_attention_kwargs=cross_attention_kwargs, encoder_attention_mask=encoder_attention_mask, **additional_residuals, ) else: additional_residuals = {} if is_brushnet and len(down_block_add_samples) > 0: additional_residuals["down_block_add_samples"] = [ down_block_add_samples.pop(0) for _ in range( len(downsample_block.resnets) + (downsample_block.downsamplers != None) ) ] sample, res_samples = downsample_block( hidden_states=sample, temb=emb, scale=lora_scale, **additional_residuals, ) if is_adapter and len(down_intrablock_additional_residuals) > 0: sample += down_intrablock_additional_residuals.pop(0) down_block_res_samples += res_samples if is_controlnet: new_down_block_res_samples = () for down_block_res_sample, down_block_additional_residual in zip( down_block_res_samples, down_block_additional_residuals ): down_block_res_sample = ( down_block_res_sample + down_block_additional_residual ) new_down_block_res_samples = new_down_block_res_samples + ( down_block_res_sample, ) down_block_res_samples = new_down_block_res_samples # 4. mid if self.mid_block is not None: if ( hasattr(self.mid_block, "has_cross_attention") and self.mid_block.has_cross_attention ): sample = self.mid_block( sample, emb, encoder_hidden_states=encoder_hidden_states, attention_mask=attention_mask, cross_attention_kwargs=cross_attention_kwargs, encoder_attention_mask=encoder_attention_mask, ) else: sample = self.mid_block(sample, emb) # To support T2I-Adapter-XL if ( is_adapter and len(down_intrablock_additional_residuals) > 0 and sample.shape == down_intrablock_additional_residuals[0].shape ): sample += down_intrablock_additional_residuals.pop(0) if is_controlnet: sample = sample + mid_block_additional_residual if is_brushnet: sample = sample + mid_block_add_sample # 5. up for i, upsample_block in enumerate(self.up_blocks): is_final_block = i == len(self.up_blocks) - 1 res_samples = down_block_res_samples[-len(upsample_block.resnets) :] down_block_res_samples = down_block_res_samples[: -len(upsample_block.resnets)] # if we have not reached the final block and need to forward the # upsample size, we do it here if not is_final_block and forward_upsample_size: upsample_size = down_block_res_samples[-1].shape[2:] if ( hasattr(upsample_block, "has_cross_attention") and upsample_block.has_cross_attention ): additional_residuals = {} if is_brushnet and len(up_block_add_samples) > 0: additional_residuals["up_block_add_samples"] = [ up_block_add_samples.pop(0) for _ in range( len(upsample_block.resnets) + (upsample_block.upsamplers != None) ) ] sample = upsample_block( hidden_states=sample, temb=emb, res_hidden_states_tuple=res_samples, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, upsample_size=upsample_size, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, **additional_residuals, ) else: additional_residuals = {} if is_brushnet and len(up_block_add_samples) > 0: additional_residuals["up_block_add_samples"] = [ up_block_add_samples.pop(0) for _ in range( len(upsample_block.resnets) + (upsample_block.upsamplers != None) ) ] sample = upsample_block( hidden_states=sample, temb=emb, res_hidden_states_tuple=res_samples, upsample_size=upsample_size, scale=lora_scale, **additional_residuals, ) # 6. post-process if self.conv_norm_out: sample = self.conv_norm_out(sample) sample = self.conv_act(sample) sample = self.conv_out(sample) if USE_PEFT_BACKEND: # remove `lora_scale` from each PEFT layer unscale_lora_layers(self, lora_scale) if not return_dict: return (sample,) return UNet2DConditionOutput(sample=sample)