# Adapted from https://github.com/huggingface/diffusers/blob/main/src/diffusers/models/unet_2d_blocks.py from typing import Any, Dict, Optional, Tuple, Union import numpy as np import torch import torch.nn.functional as F from diffusers.models.activations import get_activation from diffusers.models.attention_processor import Attention from diffusers.models.dual_transformer_2d import DualTransformer2DModel from diffusers.models.resnet import Downsample2D, ResnetBlock2D, Upsample2D from diffusers.utils import is_torch_version, logging from diffusers.utils.torch_utils import apply_freeu from torch import nn from .transformer_2d import Transformer2DModel logger = logging.get_logger(__name__) # pylint: disable=invalid-name def get_down_block( down_block_type: str, num_layers: int, in_channels: int, out_channels: int, temb_channels: int, add_downsample: bool, resnet_eps: float, resnet_act_fn: str, transformer_layers_per_block: int = 1, num_attention_heads: Optional[int] = None, resnet_groups: Optional[int] = None, cross_attention_dim: Optional[int] = None, downsample_padding: Optional[int] = None, dual_cross_attention: bool = False, use_linear_projection: bool = False, only_cross_attention: bool = False, upcast_attention: bool = False, resnet_time_scale_shift: str = "default", attention_type: str = "default", resnet_skip_time_act: bool = False, resnet_out_scale_factor: float = 1.0, cross_attention_norm: Optional[str] = None, attention_head_dim: Optional[int] = None, downsample_type: Optional[str] = None, dropout: float = 0.0, ): # If attn head dim is not defined, we default it to the number of heads if attention_head_dim is None: logger.warn( f"It is recommended to provide `attention_head_dim` when calling `get_down_block`. Defaulting `attention_head_dim` to {num_attention_heads}." ) attention_head_dim = num_attention_heads down_block_type = ( down_block_type[7:] if down_block_type.startswith("UNetRes") else down_block_type ) if down_block_type == "DownBlock2D": return DownBlock2D( num_layers=num_layers, in_channels=in_channels, out_channels=out_channels, temb_channels=temb_channels, dropout=dropout, add_downsample=add_downsample, resnet_eps=resnet_eps, resnet_act_fn=resnet_act_fn, resnet_groups=resnet_groups, downsample_padding=downsample_padding, resnet_time_scale_shift=resnet_time_scale_shift, ) elif down_block_type == "CrossAttnDownBlock2D": if cross_attention_dim is None: raise ValueError( "cross_attention_dim must be specified for CrossAttnDownBlock2D" ) return CrossAttnDownBlock2D( num_layers=num_layers, transformer_layers_per_block=transformer_layers_per_block, in_channels=in_channels, out_channels=out_channels, temb_channels=temb_channels, dropout=dropout, add_downsample=add_downsample, resnet_eps=resnet_eps, resnet_act_fn=resnet_act_fn, resnet_groups=resnet_groups, downsample_padding=downsample_padding, cross_attention_dim=cross_attention_dim, num_attention_heads=num_attention_heads, dual_cross_attention=dual_cross_attention, use_linear_projection=use_linear_projection, only_cross_attention=only_cross_attention, upcast_attention=upcast_attention, resnet_time_scale_shift=resnet_time_scale_shift, attention_type=attention_type, ) raise ValueError(f"{down_block_type} does not exist.") def get_up_block( up_block_type: str, num_layers: int, in_channels: int, out_channels: int, prev_output_channel: int, temb_channels: int, add_upsample: bool, resnet_eps: float, resnet_act_fn: str, resolution_idx: Optional[int] = None, transformer_layers_per_block: int = 1, num_attention_heads: Optional[int] = None, resnet_groups: Optional[int] = None, cross_attention_dim: Optional[int] = None, dual_cross_attention: bool = False, use_linear_projection: bool = False, only_cross_attention: bool = False, upcast_attention: bool = False, resnet_time_scale_shift: str = "default", attention_type: str = "default", resnet_skip_time_act: bool = False, resnet_out_scale_factor: float = 1.0, cross_attention_norm: Optional[str] = None, attention_head_dim: Optional[int] = None, upsample_type: Optional[str] = None, dropout: float = 0.0, ) -> nn.Module: # If attn head dim is not defined, we default it to the number of heads if attention_head_dim is None: logger.warn( f"It is recommended to provide `attention_head_dim` when calling `get_up_block`. Defaulting `attention_head_dim` to {num_attention_heads}." ) attention_head_dim = num_attention_heads up_block_type = ( up_block_type[7:] if up_block_type.startswith("UNetRes") else up_block_type ) if up_block_type == "UpBlock2D": return UpBlock2D( num_layers=num_layers, in_channels=in_channels, out_channels=out_channels, prev_output_channel=prev_output_channel, temb_channels=temb_channels, resolution_idx=resolution_idx, dropout=dropout, add_upsample=add_upsample, resnet_eps=resnet_eps, resnet_act_fn=resnet_act_fn, resnet_groups=resnet_groups, resnet_time_scale_shift=resnet_time_scale_shift, ) elif up_block_type == "CrossAttnUpBlock2D": if cross_attention_dim is None: raise ValueError( "cross_attention_dim must be specified for CrossAttnUpBlock2D" ) return CrossAttnUpBlock2D( num_layers=num_layers, transformer_layers_per_block=transformer_layers_per_block, in_channels=in_channels, out_channels=out_channels, prev_output_channel=prev_output_channel, temb_channels=temb_channels, resolution_idx=resolution_idx, dropout=dropout, add_upsample=add_upsample, resnet_eps=resnet_eps, resnet_act_fn=resnet_act_fn, resnet_groups=resnet_groups, cross_attention_dim=cross_attention_dim, num_attention_heads=num_attention_heads, dual_cross_attention=dual_cross_attention, use_linear_projection=use_linear_projection, only_cross_attention=only_cross_attention, upcast_attention=upcast_attention, resnet_time_scale_shift=resnet_time_scale_shift, attention_type=attention_type, ) raise ValueError(f"{up_block_type} does not exist.") class AutoencoderTinyBlock(nn.Module): """ Tiny Autoencoder block used in [`AutoencoderTiny`]. It is a mini residual module consisting of plain conv + ReLU blocks. Args: in_channels (`int`): The number of input channels. out_channels (`int`): The number of output channels. act_fn (`str`): ` The activation function to use. Supported values are `"swish"`, `"mish"`, `"gelu"`, and `"relu"`. Returns: `torch.FloatTensor`: A tensor with the same shape as the input tensor, but with the number of channels equal to `out_channels`. """ def __init__(self, in_channels: int, out_channels: int, act_fn: str): super().__init__() act_fn = get_activation(act_fn) self.conv = nn.Sequential( nn.Conv2d(in_channels, out_channels, kernel_size=3, padding=1), act_fn, nn.Conv2d(out_channels, out_channels, kernel_size=3, padding=1), act_fn, nn.Conv2d(out_channels, out_channels, kernel_size=3, padding=1), ) self.skip = ( nn.Conv2d(in_channels, out_channels, kernel_size=1, bias=False) if in_channels != out_channels else nn.Identity() ) self.fuse = nn.ReLU() def forward(self, x: torch.FloatTensor) -> torch.FloatTensor: return self.fuse(self.conv(x) + self.skip(x)) class UNetMidBlock2D(nn.Module): """ A 2D UNet mid-block [`UNetMidBlock2D`] with multiple residual blocks and optional attention blocks. Args: in_channels (`int`): The number of input channels. temb_channels (`int`): The number of temporal embedding channels. dropout (`float`, *optional*, defaults to 0.0): The dropout rate. num_layers (`int`, *optional*, defaults to 1): The number of residual blocks. resnet_eps (`float`, *optional*, 1e-6 ): The epsilon value for the resnet blocks. resnet_time_scale_shift (`str`, *optional*, defaults to `default`): The type of normalization to apply to the time embeddings. This can help to improve the performance of the model on tasks with long-range temporal dependencies. resnet_act_fn (`str`, *optional*, defaults to `swish`): The activation function for the resnet blocks. resnet_groups (`int`, *optional*, defaults to 32): The number of groups to use in the group normalization layers of the resnet blocks. attn_groups (`Optional[int]`, *optional*, defaults to None): The number of groups for the attention blocks. resnet_pre_norm (`bool`, *optional*, defaults to `True`): Whether to use pre-normalization for the resnet blocks. add_attention (`bool`, *optional*, defaults to `True`): Whether to add attention blocks. attention_head_dim (`int`, *optional*, defaults to 1): Dimension of a single attention head. The number of attention heads is determined based on this value and the number of input channels. output_scale_factor (`float`, *optional*, defaults to 1.0): The output scale factor. Returns: `torch.FloatTensor`: The output of the last residual block, which is a tensor of shape `(batch_size, in_channels, height, width)`. """ def __init__( self, in_channels: int, temb_channels: int, dropout: float = 0.0, num_layers: int = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", # default, spatial resnet_act_fn: str = "swish", resnet_groups: int = 32, attn_groups: Optional[int] = None, resnet_pre_norm: bool = True, add_attention: bool = True, attention_head_dim: int = 1, output_scale_factor: float = 1.0, ): super().__init__() resnet_groups = ( resnet_groups if resnet_groups is not None else min(in_channels // 4, 32) ) self.add_attention = add_attention if attn_groups is None: attn_groups = ( resnet_groups if resnet_time_scale_shift == "default" else None ) # there is always at least one resnet resnets = [ ResnetBlock2D( in_channels=in_channels, out_channels=in_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ] attentions = [] if attention_head_dim is None: logger.warn( f"It is not recommend to pass `attention_head_dim=None`. Defaulting `attention_head_dim` to `in_channels`: {in_channels}." ) attention_head_dim = in_channels for _ in range(num_layers): if self.add_attention: attentions.append( Attention( in_channels, heads=in_channels // attention_head_dim, dim_head=attention_head_dim, rescale_output_factor=output_scale_factor, eps=resnet_eps, norm_num_groups=attn_groups, spatial_norm_dim=temb_channels if resnet_time_scale_shift == "spatial" else None, residual_connection=True, bias=True, upcast_softmax=True, _from_deprecated_attn_block=True, ) ) else: attentions.append(None) resnets.append( ResnetBlock2D( in_channels=in_channels, out_channels=in_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) self.attentions = nn.ModuleList(attentions) self.resnets = nn.ModuleList(resnets) def forward( self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None ) -> torch.FloatTensor: hidden_states = self.resnets[0](hidden_states, temb) for attn, resnet in zip(self.attentions, self.resnets[1:]): if attn is not None: hidden_states = attn(hidden_states, temb=temb) hidden_states = resnet(hidden_states, temb) return hidden_states class UNetMidBlock2DCrossAttn(nn.Module): def __init__( self, in_channels: int, temb_channels: int, dropout: float = 0.0, num_layers: int = 1, transformer_layers_per_block: Union[int, Tuple[int]] = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", resnet_act_fn: str = "swish", resnet_groups: int = 32, resnet_pre_norm: bool = True, num_attention_heads: int = 1, output_scale_factor: float = 1.0, cross_attention_dim: int = 1280, dual_cross_attention: bool = False, use_linear_projection: bool = False, upcast_attention: bool = False, attention_type: str = "default", ): super().__init__() self.has_cross_attention = True self.num_attention_heads = num_attention_heads resnet_groups = ( resnet_groups if resnet_groups is not None else min(in_channels // 4, 32) ) # support for variable transformer layers per block if isinstance(transformer_layers_per_block, int): transformer_layers_per_block = [transformer_layers_per_block] * num_layers # there is always at least one resnet resnets = [ ResnetBlock2D( in_channels=in_channels, out_channels=in_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ] attentions = [] for i in range(num_layers): if not dual_cross_attention: attentions.append( Transformer2DModel( num_attention_heads, in_channels // num_attention_heads, in_channels=in_channels, num_layers=transformer_layers_per_block[i], cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, use_linear_projection=use_linear_projection, upcast_attention=upcast_attention, attention_type=attention_type, ) ) else: attentions.append( DualTransformer2DModel( num_attention_heads, in_channels // num_attention_heads, in_channels=in_channels, num_layers=1, cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, ) ) resnets.append( ResnetBlock2D( in_channels=in_channels, out_channels=in_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) self.attentions = nn.ModuleList(attentions) self.resnets = nn.ModuleList(resnets) self.gradient_checkpointing = False def forward( self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None, encoder_hidden_states: Optional[torch.FloatTensor] = None, attention_mask: Optional[torch.FloatTensor] = None, cross_attention_kwargs: Optional[Dict[str, Any]] = None, encoder_attention_mask: Optional[torch.FloatTensor] = None, ) -> torch.FloatTensor: lora_scale = ( cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0 ) hidden_states = self.resnets[0](hidden_states, temb, scale=lora_scale) for attn, resnet in zip(self.attentions, self.resnets[1:]): if self.training and self.gradient_checkpointing: def create_custom_forward(module, return_dict=None): def custom_forward(*inputs): if return_dict is not None: return module(*inputs, return_dict=return_dict) else: return module(*inputs) return custom_forward ckpt_kwargs: Dict[str, Any] = ( {"use_reentrant": False} if is_torch_version(">=", "1.11.0") else {} ) hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb, **ckpt_kwargs, ) else: hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) hidden_states = resnet(hidden_states, temb, scale=lora_scale) return hidden_states class CrossAttnDownBlock2D(nn.Module): def __init__( self, in_channels: int, out_channels: int, temb_channels: int, dropout: float = 0.0, num_layers: int = 1, transformer_layers_per_block: Union[int, Tuple[int]] = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", resnet_act_fn: str = "swish", resnet_groups: int = 32, resnet_pre_norm: bool = True, num_attention_heads: int = 1, cross_attention_dim: int = 1280, output_scale_factor: float = 1.0, downsample_padding: int = 1, add_downsample: bool = True, dual_cross_attention: bool = False, use_linear_projection: bool = False, only_cross_attention: bool = False, upcast_attention: bool = False, attention_type: str = "default", ): super().__init__() resnets = [] attentions = [] self.has_cross_attention = True self.num_attention_heads = num_attention_heads if isinstance(transformer_layers_per_block, int): transformer_layers_per_block = [transformer_layers_per_block] * num_layers for i in range(num_layers): in_channels = in_channels if i == 0 else out_channels resnets.append( ResnetBlock2D( in_channels=in_channels, out_channels=out_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) if not dual_cross_attention: attentions.append( Transformer2DModel( num_attention_heads, out_channels // num_attention_heads, in_channels=out_channels, num_layers=transformer_layers_per_block[i], cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, use_linear_projection=use_linear_projection, only_cross_attention=only_cross_attention, upcast_attention=upcast_attention, attention_type=attention_type, ) ) else: attentions.append( DualTransformer2DModel( num_attention_heads, out_channels // num_attention_heads, in_channels=out_channels, num_layers=1, cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, ) ) self.attentions = nn.ModuleList(attentions) self.resnets = nn.ModuleList(resnets) if add_downsample: self.downsamplers = nn.ModuleList( [ Downsample2D( out_channels, use_conv=True, out_channels=out_channels, padding=downsample_padding, name="op", ) ] ) else: self.downsamplers = None self.gradient_checkpointing = False def forward( self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None, encoder_hidden_states: Optional[torch.FloatTensor] = None, attention_mask: Optional[torch.FloatTensor] = None, cross_attention_kwargs: Optional[Dict[str, Any]] = None, encoder_attention_mask: Optional[torch.FloatTensor] = None, additional_residuals: Optional[torch.FloatTensor] = None, ) -> Tuple[torch.FloatTensor, Tuple[torch.FloatTensor, ...]]: output_states = () lora_scale = ( cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0 ) blocks = list(zip(self.resnets, self.attentions)) for i, (resnet, attn) in enumerate(blocks): if self.training and self.gradient_checkpointing: def create_custom_forward(module, return_dict=None): def custom_forward(*inputs): if return_dict is not None: return module(*inputs, return_dict=return_dict) else: return module(*inputs) return custom_forward ckpt_kwargs: Dict[str, Any] = ( {"use_reentrant": False} if is_torch_version(">=", "1.11.0") else {} ) hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb, **ckpt_kwargs, ) hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) else: hidden_states = resnet(hidden_states, temb, scale=lora_scale) hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) # apply additional residuals to the output of the last pair of resnet and attention blocks if i == len(blocks) - 1 and additional_residuals is not None: hidden_states = hidden_states + additional_residuals output_states = output_states + (hidden_states,) if self.downsamplers is not None: for downsampler in self.downsamplers: hidden_states = downsampler(hidden_states, scale=lora_scale) output_states = output_states + (hidden_states,) return hidden_states, output_states class DownBlock2D(nn.Module): def __init__( self, in_channels: int, out_channels: int, temb_channels: int, dropout: float = 0.0, num_layers: int = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", resnet_act_fn: str = "swish", resnet_groups: int = 32, resnet_pre_norm: bool = True, output_scale_factor: float = 1.0, add_downsample: bool = True, downsample_padding: int = 1, ): super().__init__() resnets = [] for i in range(num_layers): in_channels = in_channels if i == 0 else out_channels resnets.append( ResnetBlock2D( in_channels=in_channels, out_channels=out_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) self.resnets = nn.ModuleList(resnets) if add_downsample: self.downsamplers = nn.ModuleList( [ Downsample2D( out_channels, use_conv=True, out_channels=out_channels, padding=downsample_padding, name="op", ) ] ) else: self.downsamplers = None self.gradient_checkpointing = False def forward( self, hidden_states: torch.FloatTensor, temb: Optional[torch.FloatTensor] = None, scale: float = 1.0, ) -> Tuple[torch.FloatTensor, Tuple[torch.FloatTensor, ...]]: output_states = () for resnet in self.resnets: if self.training and self.gradient_checkpointing: def create_custom_forward(module): def custom_forward(*inputs): return module(*inputs) return custom_forward if is_torch_version(">=", "1.11.0"): hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb, use_reentrant=False, ) else: hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb ) else: hidden_states = resnet(hidden_states, temb, scale=scale) output_states = output_states + (hidden_states,) if self.downsamplers is not None: for downsampler in self.downsamplers: hidden_states = downsampler(hidden_states, scale=scale) output_states = output_states + (hidden_states,) return hidden_states, output_states class CrossAttnUpBlock2D(nn.Module): def __init__( self, in_channels: int, out_channels: int, prev_output_channel: int, temb_channels: int, resolution_idx: Optional[int] = None, dropout: float = 0.0, num_layers: int = 1, transformer_layers_per_block: Union[int, Tuple[int]] = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", resnet_act_fn: str = "swish", resnet_groups: int = 32, resnet_pre_norm: bool = True, num_attention_heads: int = 1, cross_attention_dim: int = 1280, output_scale_factor: float = 1.0, add_upsample: bool = True, dual_cross_attention: bool = False, use_linear_projection: bool = False, only_cross_attention: bool = False, upcast_attention: bool = False, attention_type: str = "default", ): super().__init__() resnets = [] attentions = [] self.has_cross_attention = True self.num_attention_heads = num_attention_heads if isinstance(transformer_layers_per_block, int): transformer_layers_per_block = [transformer_layers_per_block] * num_layers for i in range(num_layers): res_skip_channels = in_channels if (i == num_layers - 1) else out_channels resnet_in_channels = prev_output_channel if i == 0 else out_channels resnets.append( ResnetBlock2D( in_channels=resnet_in_channels + res_skip_channels, out_channels=out_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) if not dual_cross_attention: attentions.append( Transformer2DModel( num_attention_heads, out_channels // num_attention_heads, in_channels=out_channels, num_layers=transformer_layers_per_block[i], cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, use_linear_projection=use_linear_projection, only_cross_attention=only_cross_attention, upcast_attention=upcast_attention, attention_type=attention_type, ) ) else: attentions.append( DualTransformer2DModel( num_attention_heads, out_channels // num_attention_heads, in_channels=out_channels, num_layers=1, cross_attention_dim=cross_attention_dim, norm_num_groups=resnet_groups, ) ) self.attentions = nn.ModuleList(attentions) self.resnets = nn.ModuleList(resnets) if add_upsample: self.upsamplers = nn.ModuleList( [Upsample2D(out_channels, use_conv=True, out_channels=out_channels)] ) else: self.upsamplers = None self.gradient_checkpointing = False self.resolution_idx = resolution_idx def forward( self, hidden_states: torch.FloatTensor, res_hidden_states_tuple: Tuple[torch.FloatTensor, ...], temb: Optional[torch.FloatTensor] = None, encoder_hidden_states: Optional[torch.FloatTensor] = None, cross_attention_kwargs: Optional[Dict[str, Any]] = None, upsample_size: Optional[int] = None, attention_mask: Optional[torch.FloatTensor] = None, encoder_attention_mask: Optional[torch.FloatTensor] = None, ) -> torch.FloatTensor: lora_scale = ( cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0 ) is_freeu_enabled = ( getattr(self, "s1", None) and getattr(self, "s2", None) and getattr(self, "b1", None) and getattr(self, "b2", None) ) for resnet, attn in zip(self.resnets, self.attentions): # pop res hidden states res_hidden_states = res_hidden_states_tuple[-1] res_hidden_states_tuple = res_hidden_states_tuple[:-1] # FreeU: Only operate on the first two stages if is_freeu_enabled: hidden_states, res_hidden_states = apply_freeu( self.resolution_idx, hidden_states, res_hidden_states, s1=self.s1, s2=self.s2, b1=self.b1, b2=self.b2, ) hidden_states = torch.cat([hidden_states, res_hidden_states], dim=1) if self.training and self.gradient_checkpointing: def create_custom_forward(module, return_dict=None): def custom_forward(*inputs): if return_dict is not None: return module(*inputs, return_dict=return_dict) else: return module(*inputs) return custom_forward ckpt_kwargs: Dict[str, Any] = ( {"use_reentrant": False} if is_torch_version(">=", "1.11.0") else {} ) hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb, **ckpt_kwargs, ) hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) else: hidden_states = resnet(hidden_states, temb, scale=lora_scale) hidden_states, ref_feature = attn( hidden_states, encoder_hidden_states=encoder_hidden_states, cross_attention_kwargs=cross_attention_kwargs, attention_mask=attention_mask, encoder_attention_mask=encoder_attention_mask, return_dict=False, ) if self.upsamplers is not None: for upsampler in self.upsamplers: hidden_states = upsampler( hidden_states, upsample_size, scale=lora_scale ) return hidden_states class UpBlock2D(nn.Module): def __init__( self, in_channels: int, prev_output_channel: int, out_channels: int, temb_channels: int, resolution_idx: Optional[int] = None, dropout: float = 0.0, num_layers: int = 1, resnet_eps: float = 1e-6, resnet_time_scale_shift: str = "default", resnet_act_fn: str = "swish", resnet_groups: int = 32, resnet_pre_norm: bool = True, output_scale_factor: float = 1.0, add_upsample: bool = True, ): super().__init__() resnets = [] for i in range(num_layers): res_skip_channels = in_channels if (i == num_layers - 1) else out_channels resnet_in_channels = prev_output_channel if i == 0 else out_channels resnets.append( ResnetBlock2D( in_channels=resnet_in_channels + res_skip_channels, out_channels=out_channels, temb_channels=temb_channels, eps=resnet_eps, groups=resnet_groups, dropout=dropout, time_embedding_norm=resnet_time_scale_shift, non_linearity=resnet_act_fn, output_scale_factor=output_scale_factor, pre_norm=resnet_pre_norm, ) ) self.resnets = nn.ModuleList(resnets) if add_upsample: self.upsamplers = nn.ModuleList( [Upsample2D(out_channels, use_conv=True, out_channels=out_channels)] ) else: self.upsamplers = None self.gradient_checkpointing = False self.resolution_idx = resolution_idx def forward( self, hidden_states: torch.FloatTensor, res_hidden_states_tuple: Tuple[torch.FloatTensor, ...], temb: Optional[torch.FloatTensor] = None, upsample_size: Optional[int] = None, scale: float = 1.0, ) -> torch.FloatTensor: is_freeu_enabled = ( getattr(self, "s1", None) and getattr(self, "s2", None) and getattr(self, "b1", None) and getattr(self, "b2", None) ) for resnet in self.resnets: # pop res hidden states res_hidden_states = res_hidden_states_tuple[-1] res_hidden_states_tuple = res_hidden_states_tuple[:-1] # FreeU: Only operate on the first two stages if is_freeu_enabled: hidden_states, res_hidden_states = apply_freeu( self.resolution_idx, hidden_states, res_hidden_states, s1=self.s1, s2=self.s2, b1=self.b1, b2=self.b2, ) hidden_states = torch.cat([hidden_states, res_hidden_states], dim=1) if self.training and self.gradient_checkpointing: def create_custom_forward(module): def custom_forward(*inputs): return module(*inputs) return custom_forward if is_torch_version(">=", "1.11.0"): hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb, use_reentrant=False, ) else: hidden_states = torch.utils.checkpoint.checkpoint( create_custom_forward(resnet), hidden_states, temb ) else: hidden_states = resnet(hidden_states, temb, scale=scale) if self.upsamplers is not None: for upsampler in self.upsamplers: hidden_states = upsampler(hidden_states, upsample_size, scale=scale) return hidden_states