LinB203
update
bab971b
from importlib import import_module
import numpy as np
from typing import Any, Dict, Optional, Tuple, Callable
from diffusers.utils import USE_PEFT_BACKEND, BaseOutput, deprecate, is_xformers_available
from diffusers.models.lora import LoRACompatibleConv, LoRACompatibleLinear
import torch
import torch.nn.functional as F
from torch import nn
from diffusers.utils.torch_utils import maybe_allow_in_graph
from diffusers.models.embeddings import SinusoidalPositionalEmbedding, TimestepEmbedding, Timesteps
from diffusers.models.normalization import AdaLayerNorm, AdaLayerNormZero
from diffusers.models.attention_processor import SpatialNorm, LORA_ATTENTION_PROCESSORS, \
CustomDiffusionAttnProcessor, CustomDiffusionXFormersAttnProcessor, CustomDiffusionAttnProcessor2_0, \
AttnAddedKVProcessor, AttnAddedKVProcessor2_0, SlicedAttnAddedKVProcessor, XFormersAttnAddedKVProcessor, \
LoRAAttnAddedKVProcessor, LoRAXFormersAttnProcessor, XFormersAttnProcessor, LoRAAttnProcessor2_0, LoRAAttnProcessor, \
AttnProcessor, SlicedAttnProcessor, logger
from diffusers.models.activations import GEGLU, GELU, ApproximateGELU
from dataclasses import dataclass
from opensora.models.diffusion.utils.pos_embed import get_2d_sincos_pos_embed, RoPE1D, RoPE2D, LinearScalingRoPE2D, LinearScalingRoPE1D
if is_xformers_available():
import xformers
import xformers.ops
else:
xformers = None
class CombinedTimestepSizeEmbeddings(nn.Module):
"""
For PixArt-Alpha.
Reference:
https://github.com/PixArt-alpha/PixArt-alpha/blob/0f55e922376d8b797edd44d25d0e7464b260dcab/diffusion/model/nets/PixArtMS.py#L164C9-L168C29
"""
def __init__(self, embedding_dim, size_emb_dim, use_additional_conditions: bool = False):
super().__init__()
self.outdim = size_emb_dim
self.time_proj = Timesteps(num_channels=256, flip_sin_to_cos=True, downscale_freq_shift=0)
self.timestep_embedder = TimestepEmbedding(in_channels=256, time_embed_dim=embedding_dim)
self.use_additional_conditions = use_additional_conditions
if use_additional_conditions:
self.use_additional_conditions = True
self.additional_condition_proj = Timesteps(num_channels=256, flip_sin_to_cos=True, downscale_freq_shift=0)
self.resolution_embedder = TimestepEmbedding(in_channels=256, time_embed_dim=size_emb_dim)
self.aspect_ratio_embedder = TimestepEmbedding(in_channels=256, time_embed_dim=size_emb_dim)
def apply_condition(self, size: torch.Tensor, batch_size: int, embedder: nn.Module):
if size.ndim == 1:
size = size[:, None]
if size.shape[0] != batch_size:
size = size.repeat(batch_size // size.shape[0], 1)
if size.shape[0] != batch_size:
raise ValueError(f"`batch_size` should be {size.shape[0]} but found {batch_size}.")
current_batch_size, dims = size.shape[0], size.shape[1]
size = size.reshape(-1)
size_freq = self.additional_condition_proj(size).to(size.dtype)
size_emb = embedder(size_freq)
size_emb = size_emb.reshape(current_batch_size, dims * self.outdim)
return size_emb
def forward(self, timestep, resolution, aspect_ratio, batch_size, hidden_dtype):
timesteps_proj = self.time_proj(timestep)
timesteps_emb = self.timestep_embedder(timesteps_proj.to(dtype=hidden_dtype)) # (N, D)
if self.use_additional_conditions:
resolution = self.apply_condition(resolution, batch_size=batch_size, embedder=self.resolution_embedder)
aspect_ratio = self.apply_condition(
aspect_ratio, batch_size=batch_size, embedder=self.aspect_ratio_embedder
)
conditioning = timesteps_emb + torch.cat([resolution, aspect_ratio], dim=1)
else:
conditioning = timesteps_emb
return conditioning
class CaptionProjection(nn.Module):
"""
Projects caption embeddings. Also handles dropout for classifier-free guidance.
Adapted from https://github.com/PixArt-alpha/PixArt-alpha/blob/master/diffusion/model/nets/PixArt_blocks.py
"""
def __init__(self, in_features, hidden_size, num_tokens=120):
super().__init__()
self.linear_1 = nn.Linear(in_features=in_features, out_features=hidden_size, bias=True)
self.act_1 = nn.GELU(approximate="tanh")
self.linear_2 = nn.Linear(in_features=hidden_size, out_features=hidden_size, bias=True)
self.register_buffer("y_embedding", nn.Parameter(torch.randn(num_tokens, in_features) / in_features**0.5))
def forward(self, caption, force_drop_ids=None):
hidden_states = self.linear_1(caption)
hidden_states = self.act_1(hidden_states)
hidden_states = self.linear_2(hidden_states)
return hidden_states
class PatchEmbed(nn.Module):
"""2D Image to Patch Embedding"""
def __init__(
self,
height=224,
width=224,
patch_size=16,
in_channels=3,
embed_dim=768,
layer_norm=False,
flatten=True,
bias=True,
interpolation_scale=1,
):
super().__init__()
num_patches = (height // patch_size) * (width // patch_size)
self.flatten = flatten
self.layer_norm = layer_norm
self.proj = nn.Conv2d(
in_channels, embed_dim, kernel_size=(patch_size, patch_size), stride=patch_size, bias=bias
)
if layer_norm:
self.norm = nn.LayerNorm(embed_dim, elementwise_affine=False, eps=1e-6)
else:
self.norm = None
self.patch_size = patch_size
# See:
# https://github.com/PixArt-alpha/PixArt-alpha/blob/0f55e922376d8b797edd44d25d0e7464b260dcab/diffusion/model/nets/PixArtMS.py#L161
self.height, self.width = height // patch_size, width // patch_size
self.base_size = height // patch_size
self.interpolation_scale = interpolation_scale
pos_embed = get_2d_sincos_pos_embed(
embed_dim, int(num_patches**0.5), base_size=self.base_size, interpolation_scale=self.interpolation_scale
)
self.register_buffer("pos_embed", torch.from_numpy(pos_embed).float().unsqueeze(0), persistent=False)
def forward(self, latent):
height, width = latent.shape[-2] // self.patch_size, latent.shape[-1] // self.patch_size
latent = self.proj(latent)
if self.flatten:
latent = latent.flatten(2).transpose(1, 2) # BCHW -> BNC
if self.layer_norm:
latent = self.norm(latent)
# Interpolate positional embeddings if needed.
# (For PixArt-Alpha: https://github.com/PixArt-alpha/PixArt-alpha/blob/0f55e922376d8b797edd44d25d0e7464b260dcab/diffusion/model/nets/PixArtMS.py#L162C151-L162C160)
if self.height != height or self.width != width:
# raise ValueError
pos_embed = get_2d_sincos_pos_embed(
embed_dim=self.pos_embed.shape[-1],
grid_size=(height, width),
base_size=self.base_size,
interpolation_scale=self.interpolation_scale,
)
pos_embed = torch.from_numpy(pos_embed)
pos_embed = pos_embed.float().unsqueeze(0).to(latent.device)
else:
pos_embed = self.pos_embed
return (latent + pos_embed).to(latent.dtype)
@maybe_allow_in_graph
class Attention(nn.Module):
r"""
A cross attention layer.
Parameters:
query_dim (`int`):
The number of channels in the query.
cross_attention_dim (`int`, *optional*):
The number of channels in the encoder_hidden_states. If not given, defaults to `query_dim`.
heads (`int`, *optional*, defaults to 8):
The number of heads to use for multi-head attention.
dim_head (`int`, *optional*, defaults to 64):
The number of channels in each head.
dropout (`float`, *optional*, defaults to 0.0):
The dropout probability to use.
bias (`bool`, *optional*, defaults to False):
Set to `True` for the query, key, and value linear layers to contain a bias parameter.
upcast_attention (`bool`, *optional*, defaults to False):
Set to `True` to upcast the attention computation to `float32`.
upcast_softmax (`bool`, *optional*, defaults to False):
Set to `True` to upcast the softmax computation to `float32`.
cross_attention_norm (`str`, *optional*, defaults to `None`):
The type of normalization to use for the cross attention. Can be `None`, `layer_norm`, or `group_norm`.
cross_attention_norm_num_groups (`int`, *optional*, defaults to 32):
The number of groups to use for the group norm in the cross attention.
added_kv_proj_dim (`int`, *optional*, defaults to `None`):
The number of channels to use for the added key and value projections. If `None`, no projection is used.
norm_num_groups (`int`, *optional*, defaults to `None`):
The number of groups to use for the group norm in the attention.
spatial_norm_dim (`int`, *optional*, defaults to `None`):
The number of channels to use for the spatial normalization.
out_bias (`bool`, *optional*, defaults to `True`):
Set to `True` to use a bias in the output linear layer.
scale_qk (`bool`, *optional*, defaults to `True`):
Set to `True` to scale the query and key by `1 / sqrt(dim_head)`.
only_cross_attention (`bool`, *optional*, defaults to `False`):
Set to `True` to only use cross attention and not added_kv_proj_dim. Can only be set to `True` if
`added_kv_proj_dim` is not `None`.
eps (`float`, *optional*, defaults to 1e-5):
An additional value added to the denominator in group normalization that is used for numerical stability.
rescale_output_factor (`float`, *optional*, defaults to 1.0):
A factor to rescale the output by dividing it with this value.
residual_connection (`bool`, *optional*, defaults to `False`):
Set to `True` to add the residual connection to the output.
_from_deprecated_attn_block (`bool`, *optional*, defaults to `False`):
Set to `True` if the attention block is loaded from a deprecated state dict.
processor (`AttnProcessor`, *optional*, defaults to `None`):
The attention processor to use. If `None`, defaults to `AttnProcessor2_0` if `torch 2.x` is used and
`AttnProcessor` otherwise.
"""
def __init__(
self,
query_dim: int,
cross_attention_dim: Optional[int] = None,
heads: int = 8,
dim_head: int = 64,
dropout: float = 0.0,
bias: bool = False,
upcast_attention: bool = False,
upcast_softmax: bool = False,
cross_attention_norm: Optional[str] = None,
cross_attention_norm_num_groups: int = 32,
added_kv_proj_dim: Optional[int] = None,
norm_num_groups: Optional[int] = None,
spatial_norm_dim: Optional[int] = None,
out_bias: bool = True,
scale_qk: bool = True,
only_cross_attention: bool = False,
eps: float = 1e-5,
rescale_output_factor: float = 1.0,
residual_connection: bool = False,
_from_deprecated_attn_block: bool = False,
processor: Optional["AttnProcessor"] = None,
attention_mode: str = 'xformers',
use_rope: bool = False,
rope_scaling: Optional[Dict] = None,
compress_kv_factor: Optional[Tuple] = None,
):
super().__init__()
self.inner_dim = dim_head * heads
self.cross_attention_dim = cross_attention_dim if cross_attention_dim is not None else query_dim
self.upcast_attention = upcast_attention
self.upcast_softmax = upcast_softmax
self.rescale_output_factor = rescale_output_factor
self.residual_connection = residual_connection
self.dropout = dropout
self.use_rope = use_rope
self.rope_scaling = rope_scaling
self.compress_kv_factor = compress_kv_factor
# we make use of this private variable to know whether this class is loaded
# with an deprecated state dict so that we can convert it on the fly
self._from_deprecated_attn_block = _from_deprecated_attn_block
self.scale_qk = scale_qk
self.scale = dim_head**-0.5 if self.scale_qk else 1.0
self.heads = heads
# for slice_size > 0 the attention score computation
# is split across the batch axis to save memory
# You can set slice_size with `set_attention_slice`
self.sliceable_head_dim = heads
self.added_kv_proj_dim = added_kv_proj_dim
self.only_cross_attention = only_cross_attention
if self.added_kv_proj_dim is None and self.only_cross_attention:
raise ValueError(
"`only_cross_attention` can only be set to True if `added_kv_proj_dim` is not None. Make sure to set either `only_cross_attention=False` or define `added_kv_proj_dim`."
)
if norm_num_groups is not None:
self.group_norm = nn.GroupNorm(num_channels=query_dim, num_groups=norm_num_groups, eps=eps, affine=True)
else:
self.group_norm = None
if spatial_norm_dim is not None:
self.spatial_norm = SpatialNorm(f_channels=query_dim, zq_channels=spatial_norm_dim)
else:
self.spatial_norm = None
if cross_attention_norm is None:
self.norm_cross = None
elif cross_attention_norm == "layer_norm":
self.norm_cross = nn.LayerNorm(self.cross_attention_dim)
elif cross_attention_norm == "group_norm":
if self.added_kv_proj_dim is not None:
# The given `encoder_hidden_states` are initially of shape
# (batch_size, seq_len, added_kv_proj_dim) before being projected
# to (batch_size, seq_len, cross_attention_dim). The norm is applied
# before the projection, so we need to use `added_kv_proj_dim` as
# the number of channels for the group norm.
norm_cross_num_channels = added_kv_proj_dim
else:
norm_cross_num_channels = self.cross_attention_dim
self.norm_cross = nn.GroupNorm(
num_channels=norm_cross_num_channels, num_groups=cross_attention_norm_num_groups, eps=1e-5, affine=True
)
else:
raise ValueError(
f"unknown cross_attention_norm: {cross_attention_norm}. Should be None, 'layer_norm' or 'group_norm'"
)
if USE_PEFT_BACKEND:
linear_cls = nn.Linear
else:
linear_cls = LoRACompatibleLinear
assert not (self.use_rope and (self.compress_kv_factor is not None)), "Can not both enable compressing kv and using rope"
if self.compress_kv_factor is not None:
self._init_compress()
self.to_q = linear_cls(query_dim, self.inner_dim, bias=bias)
if not self.only_cross_attention:
# only relevant for the `AddedKVProcessor` classes
self.to_k = linear_cls(self.cross_attention_dim, self.inner_dim, bias=bias)
self.to_v = linear_cls(self.cross_attention_dim, self.inner_dim, bias=bias)
else:
self.to_k = None
self.to_v = None
if self.added_kv_proj_dim is not None:
self.add_k_proj = linear_cls(added_kv_proj_dim, self.inner_dim)
self.add_v_proj = linear_cls(added_kv_proj_dim, self.inner_dim)
self.to_out = nn.ModuleList([])
self.to_out.append(linear_cls(self.inner_dim, query_dim, bias=out_bias))
self.to_out.append(nn.Dropout(dropout))
# set attention processor
# We use the AttnProcessor2_0 by default when torch 2.x is used which uses
# torch.nn.functional.scaled_dot_product_attention for native Flash/memory_efficient_attention
# but only if it has the default `scale` argument. TODO remove scale_qk check when we move to torch 2.1
if processor is None:
processor = (
AttnProcessor2_0(self.inner_dim, attention_mode, use_rope, rope_scaling=rope_scaling, compress_kv_factor=compress_kv_factor) if hasattr(F, "scaled_dot_product_attention") and self.scale_qk else AttnProcessor()
)
self.set_processor(processor)
def set_use_memory_efficient_attention_xformers(
self, use_memory_efficient_attention_xformers: bool, attention_op: Optional[Callable] = None
) -> None:
r"""
Set whether to use memory efficient attention from `xformers` or not.
Args:
use_memory_efficient_attention_xformers (`bool`):
Whether to use memory efficient attention from `xformers` or not.
attention_op (`Callable`, *optional*):
The attention operation to use. Defaults to `None` which uses the default attention operation from
`xformers`.
"""
is_lora = hasattr(self, "processor") and isinstance(
self.processor,
LORA_ATTENTION_PROCESSORS,
)
is_custom_diffusion = hasattr(self, "processor") and isinstance(
self.processor,
(CustomDiffusionAttnProcessor, CustomDiffusionXFormersAttnProcessor, CustomDiffusionAttnProcessor2_0),
)
is_added_kv_processor = hasattr(self, "processor") and isinstance(
self.processor,
(
AttnAddedKVProcessor,
AttnAddedKVProcessor2_0,
SlicedAttnAddedKVProcessor,
XFormersAttnAddedKVProcessor,
LoRAAttnAddedKVProcessor,
),
)
if use_memory_efficient_attention_xformers:
if is_added_kv_processor and (is_lora or is_custom_diffusion):
raise NotImplementedError(
f"Memory efficient attention is currently not supported for LoRA or custom diffusion for attention processor type {self.processor}"
)
if not is_xformers_available():
raise ModuleNotFoundError(
(
"Refer to https://github.com/facebookresearch/xformers for more information on how to install"
" xformers"
),
name="xformers",
)
elif not torch.cuda.is_available():
raise ValueError(
"torch.cuda.is_available() should be True but is False. xformers' memory efficient attention is"
" only available for GPU "
)
else:
try:
# Make sure we can run the memory efficient attention
_ = xformers.ops.memory_efficient_attention(
torch.randn((1, 2, 40), device="cuda"),
torch.randn((1, 2, 40), device="cuda"),
torch.randn((1, 2, 40), device="cuda"),
)
except Exception as e:
raise e
if is_lora:
# TODO (sayakpaul): should we throw a warning if someone wants to use the xformers
# variant when using PT 2.0 now that we have LoRAAttnProcessor2_0?
processor = LoRAXFormersAttnProcessor(
hidden_size=self.processor.hidden_size,
cross_attention_dim=self.processor.cross_attention_dim,
rank=self.processor.rank,
attention_op=attention_op,
)
processor.load_state_dict(self.processor.state_dict())
processor.to(self.processor.to_q_lora.up.weight.device)
elif is_custom_diffusion:
processor = CustomDiffusionXFormersAttnProcessor(
train_kv=self.processor.train_kv,
train_q_out=self.processor.train_q_out,
hidden_size=self.processor.hidden_size,
cross_attention_dim=self.processor.cross_attention_dim,
attention_op=attention_op,
)
processor.load_state_dict(self.processor.state_dict())
if hasattr(self.processor, "to_k_custom_diffusion"):
processor.to(self.processor.to_k_custom_diffusion.weight.device)
elif is_added_kv_processor:
# TODO(Patrick, Suraj, William) - currently xformers doesn't work for UnCLIP
# which uses this type of cross attention ONLY because the attention mask of format
# [0, ..., -10.000, ..., 0, ...,] is not supported
# throw warning
logger.info(
"Memory efficient attention with `xformers` might currently not work correctly if an attention mask is required for the attention operation."
)
processor = XFormersAttnAddedKVProcessor(attention_op=attention_op)
else:
processor = XFormersAttnProcessor(attention_op=attention_op)
else:
if is_lora:
attn_processor_class = (
LoRAAttnProcessor2_0 if hasattr(F, "scaled_dot_product_attention") else LoRAAttnProcessor
)
processor = attn_processor_class(
hidden_size=self.processor.hidden_size,
cross_attention_dim=self.processor.cross_attention_dim,
rank=self.processor.rank,
)
processor.load_state_dict(self.processor.state_dict())
processor.to(self.processor.to_q_lora.up.weight.device)
elif is_custom_diffusion:
attn_processor_class = (
CustomDiffusionAttnProcessor2_0
if hasattr(F, "scaled_dot_product_attention")
else CustomDiffusionAttnProcessor
)
processor = attn_processor_class(
train_kv=self.processor.train_kv,
train_q_out=self.processor.train_q_out,
hidden_size=self.processor.hidden_size,
cross_attention_dim=self.processor.cross_attention_dim,
)
processor.load_state_dict(self.processor.state_dict())
if hasattr(self.processor, "to_k_custom_diffusion"):
processor.to(self.processor.to_k_custom_diffusion.weight.device)
else:
# set attention processor
# We use the AttnProcessor2_0 by default when torch 2.x is used which uses
# torch.nn.functional.scaled_dot_product_attention for native Flash/memory_efficient_attention
# but only if it has the default `scale` argument. TODO remove scale_qk check when we move to torch 2.1
processor = (
AttnProcessor2_0()
if hasattr(F, "scaled_dot_product_attention") and self.scale_qk
else AttnProcessor()
)
self.set_processor(processor)
def set_attention_slice(self, slice_size: int) -> None:
r"""
Set the slice size for attention computation.
Args:
slice_size (`int`):
The slice size for attention computation.
"""
if slice_size is not None and slice_size > self.sliceable_head_dim:
raise ValueError(f"slice_size {slice_size} has to be smaller or equal to {self.sliceable_head_dim}.")
if slice_size is not None and self.added_kv_proj_dim is not None:
processor = SlicedAttnAddedKVProcessor(slice_size)
elif slice_size is not None:
processor = SlicedAttnProcessor(slice_size)
elif self.added_kv_proj_dim is not None:
processor = AttnAddedKVProcessor()
else:
# set attention processor
# We use the AttnProcessor2_0 by default when torch 2.x is used which uses
# torch.nn.functional.scaled_dot_product_attention for native Flash/memory_efficient_attention
# but only if it has the default `scale` argument. TODO remove scale_qk check when we move to torch 2.1
processor = (
AttnProcessor2_0() if hasattr(F, "scaled_dot_product_attention") and self.scale_qk else AttnProcessor()
)
self.set_processor(processor)
def set_processor(self, processor: "AttnProcessor", _remove_lora: bool = False) -> None:
r"""
Set the attention processor to use.
Args:
processor (`AttnProcessor`):
The attention processor to use.
_remove_lora (`bool`, *optional*, defaults to `False`):
Set to `True` to remove LoRA layers from the model.
"""
if not USE_PEFT_BACKEND and hasattr(self, "processor") and _remove_lora and self.to_q.lora_layer is not None:
deprecate(
"set_processor to offload LoRA",
"0.26.0",
"In detail, removing LoRA layers via calling `set_default_attn_processor` is deprecated. Please make sure to call `pipe.unload_lora_weights()` instead.",
)
# TODO(Patrick, Sayak) - this can be deprecated once PEFT LoRA integration is complete
# We need to remove all LoRA layers
# Don't forget to remove ALL `_remove_lora` from the codebase
for module in self.modules():
if hasattr(module, "set_lora_layer"):
module.set_lora_layer(None)
# if current processor is in `self._modules` and if passed `processor` is not, we need to
# pop `processor` from `self._modules`
if (
hasattr(self, "processor")
and isinstance(self.processor, torch.nn.Module)
and not isinstance(processor, torch.nn.Module)
):
logger.info(f"You are removing possibly trained weights of {self.processor} with {processor}")
self._modules.pop("processor")
self.processor = processor
def get_processor(self, return_deprecated_lora: bool = False) -> "AttentionProcessor":
r"""
Get the attention processor in use.
Args:
return_deprecated_lora (`bool`, *optional*, defaults to `False`):
Set to `True` to return the deprecated LoRA attention processor.
Returns:
"AttentionProcessor": The attention processor in use.
"""
if not return_deprecated_lora:
return self.processor
# TODO(Sayak, Patrick). The rest of the function is needed to ensure backwards compatible
# serialization format for LoRA Attention Processors. It should be deleted once the integration
# with PEFT is completed.
is_lora_activated = {
name: module.lora_layer is not None
for name, module in self.named_modules()
if hasattr(module, "lora_layer")
}
# 1. if no layer has a LoRA activated we can return the processor as usual
if not any(is_lora_activated.values()):
return self.processor
# If doesn't apply LoRA do `add_k_proj` or `add_v_proj`
is_lora_activated.pop("add_k_proj", None)
is_lora_activated.pop("add_v_proj", None)
# 2. else it is not posssible that only some layers have LoRA activated
if not all(is_lora_activated.values()):
raise ValueError(
f"Make sure that either all layers or no layers have LoRA activated, but have {is_lora_activated}"
)
# 3. And we need to merge the current LoRA layers into the corresponding LoRA attention processor
non_lora_processor_cls_name = self.processor.__class__.__name__
lora_processor_cls = getattr(import_module(__name__), "LoRA" + non_lora_processor_cls_name)
hidden_size = self.inner_dim
# now create a LoRA attention processor from the LoRA layers
if lora_processor_cls in [LoRAAttnProcessor, LoRAAttnProcessor2_0, LoRAXFormersAttnProcessor]:
kwargs = {
"cross_attention_dim": self.cross_attention_dim,
"rank": self.to_q.lora_layer.rank,
"network_alpha": self.to_q.lora_layer.network_alpha,
"q_rank": self.to_q.lora_layer.rank,
"q_hidden_size": self.to_q.lora_layer.out_features,
"k_rank": self.to_k.lora_layer.rank,
"k_hidden_size": self.to_k.lora_layer.out_features,
"v_rank": self.to_v.lora_layer.rank,
"v_hidden_size": self.to_v.lora_layer.out_features,
"out_rank": self.to_out[0].lora_layer.rank,
"out_hidden_size": self.to_out[0].lora_layer.out_features,
}
if hasattr(self.processor, "attention_op"):
kwargs["attention_op"] = self.processor.attention_op
lora_processor = lora_processor_cls(hidden_size, **kwargs)
lora_processor.to_q_lora.load_state_dict(self.to_q.lora_layer.state_dict())
lora_processor.to_k_lora.load_state_dict(self.to_k.lora_layer.state_dict())
lora_processor.to_v_lora.load_state_dict(self.to_v.lora_layer.state_dict())
lora_processor.to_out_lora.load_state_dict(self.to_out[0].lora_layer.state_dict())
elif lora_processor_cls == LoRAAttnAddedKVProcessor:
lora_processor = lora_processor_cls(
hidden_size,
cross_attention_dim=self.add_k_proj.weight.shape[0],
rank=self.to_q.lora_layer.rank,
network_alpha=self.to_q.lora_layer.network_alpha,
)
lora_processor.to_q_lora.load_state_dict(self.to_q.lora_layer.state_dict())
lora_processor.to_k_lora.load_state_dict(self.to_k.lora_layer.state_dict())
lora_processor.to_v_lora.load_state_dict(self.to_v.lora_layer.state_dict())
lora_processor.to_out_lora.load_state_dict(self.to_out[0].lora_layer.state_dict())
# only save if used
if self.add_k_proj.lora_layer is not None:
lora_processor.add_k_proj_lora.load_state_dict(self.add_k_proj.lora_layer.state_dict())
lora_processor.add_v_proj_lora.load_state_dict(self.add_v_proj.lora_layer.state_dict())
else:
lora_processor.add_k_proj_lora = None
lora_processor.add_v_proj_lora = None
else:
raise ValueError(f"{lora_processor_cls} does not exist.")
return lora_processor
def forward(
self,
hidden_states: torch.FloatTensor,
encoder_hidden_states: Optional[torch.FloatTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
**cross_attention_kwargs,
) -> torch.Tensor:
r"""
The forward method of the `Attention` class.
Args:
hidden_states (`torch.Tensor`):
The hidden states of the query.
encoder_hidden_states (`torch.Tensor`, *optional*):
The hidden states of the encoder.
attention_mask (`torch.Tensor`, *optional*):
The attention mask to use. If `None`, no mask is applied.
**cross_attention_kwargs:
Additional keyword arguments to pass along to the cross attention.
Returns:
`torch.Tensor`: The output of the attention layer.
"""
# The `Attention` class can call different attention processors / attention functions
# here we simply pass along all tensors to the selected processor class
# For standard processors that are defined here, `**cross_attention_kwargs` is empty
return self.processor(
self,
hidden_states,
encoder_hidden_states=encoder_hidden_states,
attention_mask=attention_mask,
**cross_attention_kwargs,
)
def batch_to_head_dim(self, tensor: torch.Tensor) -> torch.Tensor:
r"""
Reshape the tensor from `[batch_size, seq_len, dim]` to `[batch_size // heads, seq_len, dim * heads]`. `heads`
is the number of heads initialized while constructing the `Attention` class.
Args:
tensor (`torch.Tensor`): The tensor to reshape.
Returns:
`torch.Tensor`: The reshaped tensor.
"""
head_size = self.heads
batch_size, seq_len, dim = tensor.shape
tensor = tensor.reshape(batch_size // head_size, head_size, seq_len, dim)
tensor = tensor.permute(0, 2, 1, 3).reshape(batch_size // head_size, seq_len, dim * head_size)
return tensor
def head_to_batch_dim(self, tensor: torch.Tensor, out_dim: int = 3) -> torch.Tensor:
r"""
Reshape the tensor from `[batch_size, seq_len, dim]` to `[batch_size, seq_len, heads, dim // heads]` `heads` is
the number of heads initialized while constructing the `Attention` class.
Args:
tensor (`torch.Tensor`): The tensor to reshape.
out_dim (`int`, *optional*, defaults to `3`): The output dimension of the tensor. If `3`, the tensor is
reshaped to `[batch_size * heads, seq_len, dim // heads]`.
Returns:
`torch.Tensor`: The reshaped tensor.
"""
head_size = self.heads
batch_size, seq_len, dim = tensor.shape
tensor = tensor.reshape(batch_size, seq_len, head_size, dim // head_size)
tensor = tensor.permute(0, 2, 1, 3)
if out_dim == 3:
tensor = tensor.reshape(batch_size * head_size, seq_len, dim // head_size)
return tensor
def get_attention_scores(
self, query: torch.Tensor, key: torch.Tensor, attention_mask: torch.Tensor = None
) -> torch.Tensor:
r"""
Compute the attention scores.
Args:
query (`torch.Tensor`): The query tensor.
key (`torch.Tensor`): The key tensor.
attention_mask (`torch.Tensor`, *optional*): The attention mask to use. If `None`, no mask is applied.
Returns:
`torch.Tensor`: The attention probabilities/scores.
"""
dtype = query.dtype
if self.upcast_attention:
query = query.float()
key = key.float()
if attention_mask is None:
baddbmm_input = torch.empty(
query.shape[0], query.shape[1], key.shape[1], dtype=query.dtype, device=query.device
)
beta = 0
else:
baddbmm_input = attention_mask
beta = 1
attention_scores = torch.baddbmm(
baddbmm_input,
query,
key.transpose(-1, -2),
beta=beta,
alpha=self.scale,
)
del baddbmm_input
if self.upcast_softmax:
attention_scores = attention_scores.float()
attention_probs = attention_scores.softmax(dim=-1)
del attention_scores
attention_probs = attention_probs.to(dtype)
return attention_probs
def prepare_attention_mask(
self, attention_mask: torch.Tensor, target_length: int, batch_size: int, out_dim: int = 3
) -> torch.Tensor:
r"""
Prepare the attention mask for the attention computation.
Args:
attention_mask (`torch.Tensor`):
The attention mask to prepare.
target_length (`int`):
The target length of the attention mask. This is the length of the attention mask after padding.
batch_size (`int`):
The batch size, which is used to repeat the attention mask.
out_dim (`int`, *optional*, defaults to `3`):
The output dimension of the attention mask. Can be either `3` or `4`.
Returns:
`torch.Tensor`: The prepared attention mask.
"""
head_size = self.heads
if attention_mask is None:
return attention_mask
current_length: int = attention_mask.shape[-1]
if current_length != target_length:
if attention_mask.device.type == "mps":
# HACK: MPS: Does not support padding by greater than dimension of input tensor.
# Instead, we can manually construct the padding tensor.
padding_shape = (attention_mask.shape[0], attention_mask.shape[1], target_length)
padding = torch.zeros(padding_shape, dtype=attention_mask.dtype, device=attention_mask.device)
attention_mask = torch.cat([attention_mask, padding], dim=2)
else:
# TODO: for pipelines such as stable-diffusion, padding cross-attn mask:
# we want to instead pad by (0, remaining_length), where remaining_length is:
# remaining_length: int = target_length - current_length
# TODO: re-enable tests/models/test_models_unet_2d_condition.py#test_model_xattn_padding
attention_mask = F.pad(attention_mask, (0, target_length), value=0.0)
if out_dim == 3:
if attention_mask.shape[0] < batch_size * head_size:
attention_mask = attention_mask.repeat_interleave(head_size, dim=0)
elif out_dim == 4:
attention_mask = attention_mask.unsqueeze(1)
attention_mask = attention_mask.repeat_interleave(head_size, dim=1)
return attention_mask
def norm_encoder_hidden_states(self, encoder_hidden_states: torch.Tensor) -> torch.Tensor:
r"""
Normalize the encoder hidden states. Requires `self.norm_cross` to be specified when constructing the
`Attention` class.
Args:
encoder_hidden_states (`torch.Tensor`): Hidden states of the encoder.
Returns:
`torch.Tensor`: The normalized encoder hidden states.
"""
assert self.norm_cross is not None, "self.norm_cross must be defined to call self.norm_encoder_hidden_states"
if isinstance(self.norm_cross, nn.LayerNorm):
encoder_hidden_states = self.norm_cross(encoder_hidden_states)
elif isinstance(self.norm_cross, nn.GroupNorm):
# Group norm norms along the channels dimension and expects
# input to be in the shape of (N, C, *). In this case, we want
# to norm along the hidden dimension, so we need to move
# (batch_size, sequence_length, hidden_size) ->
# (batch_size, hidden_size, sequence_length)
encoder_hidden_states = encoder_hidden_states.transpose(1, 2)
encoder_hidden_states = self.norm_cross(encoder_hidden_states)
encoder_hidden_states = encoder_hidden_states.transpose(1, 2)
else:
assert False
return encoder_hidden_states
def _init_compress(self):
if len(self.compress_kv_factor) == 2:
self.sr = nn.Conv2d(self.inner_dim, self.inner_dim, groups=self.inner_dim, kernel_size=self.compress_kv_factor, stride=self.compress_kv_factor)
self.sr.weight.data.fill_(1/self.compress_kv_factor[0]**2)
elif len(self.compress_kv_factor) == 1:
self.kernel_size = self.compress_kv_factor[0]
self.sr = nn.Conv1d(self.inner_dim, self.inner_dim, groups=self.inner_dim, kernel_size=self.compress_kv_factor[0], stride=self.compress_kv_factor[0])
self.sr.weight.data.fill_(1/self.compress_kv_factor[0])
self.sr.bias.data.zero_()
self.norm = nn.LayerNorm(self.inner_dim)
class AttnProcessor2_0:
r"""
Processor for implementing scaled dot-product attention (enabled by default if you're using PyTorch 2.0).
"""
def __init__(self, dim=1152, attention_mode='xformers', use_rope=False, rope_scaling=None, compress_kv_factor=None):
self.dim = dim
self.attention_mode = attention_mode
self.use_rope = use_rope
self.rope_scaling = rope_scaling
self.compress_kv_factor = compress_kv_factor
if self.use_rope:
self._init_rope()
if not hasattr(F, "scaled_dot_product_attention"):
raise ImportError("AttnProcessor2_0 requires PyTorch 2.0, to use it, please upgrade PyTorch to 2.0.")
def _init_rope(self):
if self.rope_scaling is None:
self.rope2d = RoPE2D()
self.rope1d = RoPE1D()
else:
scaling_type = self.rope_scaling["type"]
scaling_factor_2d = self.rope_scaling["factor_2d"]
scaling_factor_1d = self.rope_scaling["factor_1d"]
if scaling_type == "linear":
self.rope2d = LinearScalingRoPE2D(scaling_factor=scaling_factor_2d)
self.rope1d = LinearScalingRoPE1D(scaling_factor=scaling_factor_1d)
else:
raise ValueError(f"Unknown RoPE scaling type {scaling_type}")
def __call__(
self,
attn: Attention,
hidden_states: torch.FloatTensor,
encoder_hidden_states: Optional[torch.FloatTensor] = None,
attention_mask: Optional[torch.FloatTensor] = None,
temb: Optional[torch.FloatTensor] = None,
scale: float = 1.0,
position_q: Optional[torch.LongTensor] = None,
position_k: Optional[torch.LongTensor] = None,
last_shape: Tuple[int] = None,
) -> torch.FloatTensor:
residual = hidden_states
args = () if USE_PEFT_BACKEND else (scale,)
if attn.spatial_norm is not None:
hidden_states = attn.spatial_norm(hidden_states, temb)
input_ndim = hidden_states.ndim
if input_ndim == 4:
batch_size, channel, height, width = hidden_states.shape
hidden_states = hidden_states.view(batch_size, channel, height * width).transpose(1, 2)
if self.compress_kv_factor is not None:
batch_size = hidden_states.shape[0]
if len(last_shape) == 2:
encoder_hidden_states = hidden_states.permute(0, 2, 1).reshape(batch_size, self.dim, *last_shape)
encoder_hidden_states = attn.sr(encoder_hidden_states).reshape(batch_size, self.dim, -1).permute(0, 2, 1)
elif len(last_shape) == 1:
encoder_hidden_states = hidden_states.permute(0, 2, 1)
if last_shape[0] % 2 == 1:
first_frame_pad = encoder_hidden_states[:, :, :1].repeat((1, 1, attn.kernel_size - 1))
encoder_hidden_states = torch.concatenate((first_frame_pad, encoder_hidden_states), dim=2)
encoder_hidden_states = attn.sr(encoder_hidden_states).permute(0, 2, 1)
else:
raise NotImplementedError(f'NotImplementedError with last_shape {last_shape}')
encoder_hidden_states = attn.norm(encoder_hidden_states)
batch_size, sequence_length, _ = (
hidden_states.shape if encoder_hidden_states is None else encoder_hidden_states.shape
)
if attention_mask is not None:
attention_mask = attn.prepare_attention_mask(attention_mask, sequence_length, batch_size)
# scaled_dot_product_attention expects attention_mask shape to be
# (batch, heads, source_length, target_length)
attention_mask = attention_mask.view(batch_size, attn.heads, -1, attention_mask.shape[-1])
if attn.group_norm is not None:
hidden_states = attn.group_norm(hidden_states.transpose(1, 2)).transpose(1, 2)
args = () if USE_PEFT_BACKEND else (scale,)
query = attn.to_q(hidden_states, *args)
if encoder_hidden_states is None:
encoder_hidden_states = hidden_states
elif attn.norm_cross:
encoder_hidden_states = attn.norm_encoder_hidden_states(encoder_hidden_states)
key = attn.to_k(encoder_hidden_states, *args)
value = attn.to_v(encoder_hidden_states, *args)
inner_dim = key.shape[-1]
head_dim = inner_dim // attn.heads
query = query.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
key = key.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
value = value.view(batch_size, -1, attn.heads, head_dim).transpose(1, 2)
if self.use_rope:
# require the shape of (batch_size x nheads x ntokens x dim)
if position_q.ndim == 3:
query = self.rope2d(query, position_q)
elif position_q.ndim == 2:
query = self.rope1d(query, position_q)
else:
raise NotImplementedError
if position_k.ndim == 3:
key = self.rope2d(key, position_k)
elif position_k.ndim == 2:
key = self.rope1d(key, position_k)
else:
raise NotImplementedError
# the output of sdp = (batch, num_heads, seq_len, head_dim)
# TODO: add support for attn.scale when we move to Torch 2.1
if self.attention_mode == 'flash':
assert attention_mask is None or torch.all(attention_mask.bool()), 'flash-attn do not support attention_mask'
with torch.backends.cuda.sdp_kernel(enable_math=False, enable_flash=True, enable_mem_efficient=False):
hidden_states = F.scaled_dot_product_attention(
query, key, value, dropout_p=0.0, is_causal=False
)
elif self.attention_mode == 'xformers':
with torch.backends.cuda.sdp_kernel(enable_math=False, enable_flash=False, enable_mem_efficient=True):
hidden_states = F.scaled_dot_product_attention(
query, key, value, attn_mask=attention_mask, dropout_p=0.0, is_causal=False
)
elif self.attention_mode == 'math':
hidden_states = F.scaled_dot_product_attention(
query, key, value, attn_mask=attention_mask, dropout_p=0.0, is_causal=False
)
else:
raise NotImplementedError(f'Found attention_mode: {self.attention_mode}')
hidden_states = hidden_states.transpose(1, 2).reshape(batch_size, -1, attn.heads * head_dim)
hidden_states = hidden_states.to(query.dtype)
# linear proj
hidden_states = attn.to_out[0](hidden_states, *args)
# dropout
hidden_states = attn.to_out[1](hidden_states)
if input_ndim == 4:
hidden_states = hidden_states.transpose(-1, -2).reshape(batch_size, channel, height, width)
if attn.residual_connection:
hidden_states = hidden_states + residual
hidden_states = hidden_states / attn.rescale_output_factor
return hidden_states
@maybe_allow_in_graph
class GatedSelfAttentionDense(nn.Module):
r"""
A gated self-attention dense layer that combines visual features and object features.
Parameters:
query_dim (`int`): The number of channels in the query.
context_dim (`int`): The number of channels in the context.
n_heads (`int`): The number of heads to use for attention.
d_head (`int`): The number of channels in each head.
"""
def __init__(self, query_dim: int, context_dim: int, n_heads: int, d_head: int):
super().__init__()
# we need a linear projection since we need cat visual feature and obj feature
self.linear = nn.Linear(context_dim, query_dim)
self.attn = Attention(query_dim=query_dim, heads=n_heads, dim_head=d_head)
self.ff = FeedForward(query_dim, activation_fn="geglu")
self.norm1 = nn.LayerNorm(query_dim)
self.norm2 = nn.LayerNorm(query_dim)
self.register_parameter("alpha_attn", nn.Parameter(torch.tensor(0.0)))
self.register_parameter("alpha_dense", nn.Parameter(torch.tensor(0.0)))
self.enabled = True
def forward(self, x: torch.Tensor, objs: torch.Tensor) -> torch.Tensor:
if not self.enabled:
return x
n_visual = x.shape[1]
objs = self.linear(objs)
x = x + self.alpha_attn.tanh() * self.attn(self.norm1(torch.cat([x, objs], dim=1)))[:, :n_visual, :]
x = x + self.alpha_dense.tanh() * self.ff(self.norm2(x))
return x
class FeedForward(nn.Module):
r"""
A feed-forward layer.
Parameters:
dim (`int`): The number of channels in the input.
dim_out (`int`, *optional*): The number of channels in the output. If not given, defaults to `dim`.
mult (`int`, *optional*, defaults to 4): The multiplier to use for the hidden dimension.
dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to be used in feed-forward.
final_dropout (`bool` *optional*, defaults to False): Apply a final dropout.
"""
def __init__(
self,
dim: int,
dim_out: Optional[int] = None,
mult: int = 4,
dropout: float = 0.0,
activation_fn: str = "geglu",
final_dropout: bool = False,
):
super().__init__()
inner_dim = int(dim * mult)
dim_out = dim_out if dim_out is not None else dim
linear_cls = LoRACompatibleLinear if not USE_PEFT_BACKEND else nn.Linear
if activation_fn == "gelu":
act_fn = GELU(dim, inner_dim)
if activation_fn == "gelu-approximate":
act_fn = GELU(dim, inner_dim, approximate="tanh")
elif activation_fn == "geglu":
act_fn = GEGLU(dim, inner_dim)
elif activation_fn == "geglu-approximate":
act_fn = ApproximateGELU(dim, inner_dim)
self.net = nn.ModuleList([])
# project in
self.net.append(act_fn)
# project dropout
self.net.append(nn.Dropout(dropout))
# project out
self.net.append(linear_cls(inner_dim, dim_out))
# FF as used in Vision Transformer, MLP-Mixer, etc. have a final dropout
if final_dropout:
self.net.append(nn.Dropout(dropout))
def forward(self, hidden_states: torch.Tensor, scale: float = 1.0) -> torch.Tensor:
compatible_cls = (GEGLU,) if USE_PEFT_BACKEND else (GEGLU, LoRACompatibleLinear)
for module in self.net:
if isinstance(module, compatible_cls):
hidden_states = module(hidden_states, scale)
else:
hidden_states = module(hidden_states)
return hidden_states
@maybe_allow_in_graph
class BasicTransformerBlock_(nn.Module):
r"""
A basic Transformer block.
Parameters:
dim (`int`): The number of channels in the input and output.
num_attention_heads (`int`): The number of heads to use for multi-head attention.
attention_head_dim (`int`): The number of channels in each head.
dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
cross_attention_dim (`int`, *optional*): The size of the encoder_hidden_states vector for cross attention.
activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to be used in feed-forward.
num_embeds_ada_norm (:
obj: `int`, *optional*): The number of diffusion steps used during training. See `Transformer2DModel`.
attention_bias (:
obj: `bool`, *optional*, defaults to `False`): Configure if the attentions should contain a bias parameter.
only_cross_attention (`bool`, *optional*):
Whether to use only cross-attention layers. In this case two cross attention layers are used.
double_self_attention (`bool`, *optional*):
Whether to use two self-attention layers. In this case no cross attention layers are used.
upcast_attention (`bool`, *optional*):
Whether to upcast the attention computation to float32. This is useful for mixed precision training.
norm_elementwise_affine (`bool`, *optional*, defaults to `True`):
Whether to use learnable elementwise affine parameters for normalization.
norm_type (`str`, *optional*, defaults to `"layer_norm"`):
The normalization layer to use. Can be `"layer_norm"`, `"ada_norm"` or `"ada_norm_zero"`.
final_dropout (`bool` *optional*, defaults to False):
Whether to apply a final dropout after the last feed-forward layer.
attention_type (`str`, *optional*, defaults to `"default"`):
The type of attention to use. Can be `"default"` or `"gated"` or `"gated-text-image"`.
positional_embeddings (`str`, *optional*, defaults to `None`):
The type of positional embeddings to apply to.
num_positional_embeddings (`int`, *optional*, defaults to `None`):
The maximum number of positional embeddings to apply.
"""
def __init__(
self,
dim: int,
num_attention_heads: int,
attention_head_dim: int,
dropout=0.0,
cross_attention_dim: Optional[int] = None,
activation_fn: str = "geglu",
num_embeds_ada_norm: Optional[int] = None,
attention_bias: bool = False,
only_cross_attention: bool = False,
double_self_attention: bool = False,
upcast_attention: bool = False,
norm_elementwise_affine: bool = True,
norm_type: str = "layer_norm", # 'layer_norm', 'ada_norm', 'ada_norm_zero', 'ada_norm_single'
norm_eps: float = 1e-5,
final_dropout: bool = False,
attention_type: str = "default",
positional_embeddings: Optional[str] = None,
num_positional_embeddings: Optional[int] = None,
attention_mode: str = "xformers",
use_rope: bool = False,
rope_scaling: Optional[Dict] = None,
compress_kv_factor: Optional[Tuple] = None,
):
super().__init__()
self.only_cross_attention = only_cross_attention
self.use_ada_layer_norm_zero = (num_embeds_ada_norm is not None) and norm_type == "ada_norm_zero"
self.use_ada_layer_norm = (num_embeds_ada_norm is not None) and norm_type == "ada_norm"
self.use_ada_layer_norm_single = norm_type == "ada_norm_single"
self.use_layer_norm = norm_type == "layer_norm"
if norm_type in ("ada_norm", "ada_norm_zero") and num_embeds_ada_norm is None:
raise ValueError(
f"`norm_type` is set to {norm_type}, but `num_embeds_ada_norm` is not defined. Please make sure to"
f" define `num_embeds_ada_norm` if setting `norm_type` to {norm_type}."
)
if positional_embeddings and (num_positional_embeddings is None):
raise ValueError(
"If `positional_embedding` type is defined, `num_positition_embeddings` must also be defined."
)
if positional_embeddings == "sinusoidal":
self.pos_embed = SinusoidalPositionalEmbedding(dim, max_seq_length=num_positional_embeddings)
else:
self.pos_embed = None
# Define 3 blocks. Each block has its own normalization layer.
# 1. Self-Attn
if self.use_ada_layer_norm:
self.norm1 = AdaLayerNorm(dim, num_embeds_ada_norm)
elif self.use_ada_layer_norm_zero:
self.norm1 = AdaLayerNormZero(dim, num_embeds_ada_norm)
else:
self.norm1 = nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
self.attn1 = Attention(
query_dim=dim,
heads=num_attention_heads,
dim_head=attention_head_dim,
dropout=dropout,
bias=attention_bias,
cross_attention_dim=cross_attention_dim if only_cross_attention else None,
upcast_attention=upcast_attention,
attention_mode=attention_mode,
use_rope=use_rope,
rope_scaling=rope_scaling,
compress_kv_factor=compress_kv_factor,
)
# # 2. Cross-Attn
# if cross_attention_dim is not None or double_self_attention:
# # We currently only use AdaLayerNormZero for self attention where there will only be one attention block.
# # I.e. the number of returned modulation chunks from AdaLayerZero would not make sense if returned during
# # the second cross attention block.
# self.norm2 = (
# AdaLayerNorm(dim, num_embeds_ada_norm)
# if self.use_ada_layer_norm
# else nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
# )
# self.attn2 = Attention(
# query_dim=dim,
# cross_attention_dim=cross_attention_dim if not double_self_attention else None,
# heads=num_attention_heads,
# dim_head=attention_head_dim,
# dropout=dropout,
# bias=attention_bias,
# upcast_attention=upcast_attention,
# ) # is self-attn if encoder_hidden_states is none
# else:
# self.norm2 = None
# self.attn2 = None
# 3. Feed-forward
# if not self.use_ada_layer_norm_single:
# self.norm3 = nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
self.norm3 = nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
self.ff = FeedForward(dim, dropout=dropout, activation_fn=activation_fn, final_dropout=final_dropout)
# 4. Fuser
if attention_type == "gated" or attention_type == "gated-text-image":
self.fuser = GatedSelfAttentionDense(dim, cross_attention_dim, num_attention_heads, attention_head_dim)
# 5. Scale-shift for PixArt-Alpha.
if self.use_ada_layer_norm_single:
self.scale_shift_table = nn.Parameter(torch.randn(6, dim) / dim ** 0.5)
# let chunk size default to None
self._chunk_size = None
self._chunk_dim = 0
def set_chunk_feed_forward(self, chunk_size: Optional[int], dim: int):
# Sets chunk feed-forward
self._chunk_size = chunk_size
self._chunk_dim = dim
def forward(
self,
hidden_states: torch.FloatTensor,
attention_mask: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.FloatTensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
timestep: Optional[torch.LongTensor] = None,
cross_attention_kwargs: Dict[str, Any] = None,
class_labels: Optional[torch.LongTensor] = None,
position_q: Optional[torch.LongTensor] = None,
position_k: Optional[torch.LongTensor] = None,
frame: int = None,
) -> torch.FloatTensor:
# Notice that normalization is always applied before the real computation in the following blocks.
# 0. Self-Attention
batch_size = hidden_states.shape[0]
if self.use_ada_layer_norm:
norm_hidden_states = self.norm1(hidden_states, timestep)
elif self.use_ada_layer_norm_zero:
norm_hidden_states, gate_msa, shift_mlp, scale_mlp, gate_mlp = self.norm1(
hidden_states, timestep, class_labels, hidden_dtype=hidden_states.dtype
)
elif self.use_layer_norm:
norm_hidden_states = self.norm1(hidden_states)
elif self.use_ada_layer_norm_single:
shift_msa, scale_msa, gate_msa, shift_mlp, scale_mlp, gate_mlp = (
self.scale_shift_table[None] + timestep.reshape(batch_size, 6, -1)
).chunk(6, dim=1)
norm_hidden_states = self.norm1(hidden_states)
norm_hidden_states = norm_hidden_states * (1 + scale_msa) + shift_msa
norm_hidden_states = norm_hidden_states.squeeze(1)
else:
raise ValueError("Incorrect norm used")
if self.pos_embed is not None:
norm_hidden_states = self.pos_embed(norm_hidden_states)
# 1. Retrieve lora scale.
lora_scale = cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0
# 2. Prepare GLIGEN inputs
cross_attention_kwargs = cross_attention_kwargs.copy() if cross_attention_kwargs is not None else {}
gligen_kwargs = cross_attention_kwargs.pop("gligen", None)
attn_output = self.attn1(
norm_hidden_states,
encoder_hidden_states=encoder_hidden_states if self.only_cross_attention else None,
attention_mask=attention_mask,
position_q=position_q,
position_k=position_k,
last_shape=frame,
**cross_attention_kwargs,
)
if self.use_ada_layer_norm_zero:
attn_output = gate_msa.unsqueeze(1) * attn_output
elif self.use_ada_layer_norm_single:
attn_output = gate_msa * attn_output
hidden_states = attn_output + hidden_states
if hidden_states.ndim == 4:
hidden_states = hidden_states.squeeze(1)
# 2.5 GLIGEN Control
if gligen_kwargs is not None:
hidden_states = self.fuser(hidden_states, gligen_kwargs["objs"])
# # 3. Cross-Attention
# if self.attn2 is not None:
# if self.use_ada_layer_norm:
# norm_hidden_states = self.norm2(hidden_states, timestep)
# elif self.use_ada_layer_norm_zero or self.use_layer_norm:
# norm_hidden_states = self.norm2(hidden_states)
# elif self.use_ada_layer_norm_single:
# # For PixArt norm2 isn't applied here:
# # https://github.com/PixArt-alpha/PixArt-alpha/blob/0f55e922376d8b797edd44d25d0e7464b260dcab/diffusion/model/nets/PixArtMS.py#L70C1-L76C103
# norm_hidden_states = hidden_states
# else:
# raise ValueError("Incorrect norm")
# if self.pos_embed is not None and self.use_ada_layer_norm_single is False:
# norm_hidden_states = self.pos_embed(norm_hidden_states)
# attn_output = self.attn2(
# norm_hidden_states,
# encoder_hidden_states=encoder_hidden_states,
# attention_mask=encoder_attention_mask,
# **cross_attention_kwargs,
# )
# hidden_states = attn_output + hidden_states
# 4. Feed-forward
# if not self.use_ada_layer_norm_single:
# norm_hidden_states = self.norm3(hidden_states)
if self.use_ada_layer_norm_zero:
norm_hidden_states = norm_hidden_states * (1 + scale_mlp[:, None]) + shift_mlp[:, None]
if self.use_ada_layer_norm_single:
# norm_hidden_states = self.norm2(hidden_states)
norm_hidden_states = self.norm3(hidden_states)
norm_hidden_states = norm_hidden_states * (1 + scale_mlp) + shift_mlp
if self._chunk_size is not None:
# "feed_forward_chunk_size" can be used to save memory
if norm_hidden_states.shape[self._chunk_dim] % self._chunk_size != 0:
raise ValueError(
f"`hidden_states` dimension to be chunked: {norm_hidden_states.shape[self._chunk_dim]} has to be divisible by chunk size: {self._chunk_size}. Make sure to set an appropriate `chunk_size` when calling `unet.enable_forward_chunking`."
)
num_chunks = norm_hidden_states.shape[self._chunk_dim] // self._chunk_size
ff_output = torch.cat(
[
self.ff(hid_slice, scale=lora_scale)
for hid_slice in norm_hidden_states.chunk(num_chunks, dim=self._chunk_dim)
],
dim=self._chunk_dim,
)
else:
ff_output = self.ff(norm_hidden_states, scale=lora_scale)
if self.use_ada_layer_norm_zero:
ff_output = gate_mlp.unsqueeze(1) * ff_output
elif self.use_ada_layer_norm_single:
ff_output = gate_mlp * ff_output
hidden_states = ff_output + hidden_states
if hidden_states.ndim == 4:
hidden_states = hidden_states.squeeze(1)
return hidden_states
@maybe_allow_in_graph
class BasicTransformerBlock(nn.Module):
r"""
A basic Transformer block.
Parameters:
dim (`int`): The number of channels in the input and output.
num_attention_heads (`int`): The number of heads to use for multi-head attention.
attention_head_dim (`int`): The number of channels in each head.
dropout (`float`, *optional*, defaults to 0.0): The dropout probability to use.
cross_attention_dim (`int`, *optional*): The size of the encoder_hidden_states vector for cross attention.
activation_fn (`str`, *optional*, defaults to `"geglu"`): Activation function to be used in feed-forward.
num_embeds_ada_norm (:
obj: `int`, *optional*): The number of diffusion steps used during training. See `Transformer2DModel`.
attention_bias (:
obj: `bool`, *optional*, defaults to `False`): Configure if the attentions should contain a bias parameter.
only_cross_attention (`bool`, *optional*):
Whether to use only cross-attention layers. In this case two cross attention layers are used.
double_self_attention (`bool`, *optional*):
Whether to use two self-attention layers. In this case no cross attention layers are used.
upcast_attention (`bool`, *optional*):
Whether to upcast the attention computation to float32. This is useful for mixed precision training.
norm_elementwise_affine (`bool`, *optional*, defaults to `True`):
Whether to use learnable elementwise affine parameters for normalization.
norm_type (`str`, *optional*, defaults to `"layer_norm"`):
The normalization layer to use. Can be `"layer_norm"`, `"ada_norm"` or `"ada_norm_zero"`.
final_dropout (`bool` *optional*, defaults to False):
Whether to apply a final dropout after the last feed-forward layer.
attention_type (`str`, *optional*, defaults to `"default"`):
The type of attention to use. Can be `"default"` or `"gated"` or `"gated-text-image"`.
positional_embeddings (`str`, *optional*, defaults to `None`):
The type of positional embeddings to apply to.
num_positional_embeddings (`int`, *optional*, defaults to `None`):
The maximum number of positional embeddings to apply.
"""
def __init__(
self,
dim: int,
num_attention_heads: int,
attention_head_dim: int,
dropout=0.0,
cross_attention_dim: Optional[int] = None,
activation_fn: str = "geglu",
num_embeds_ada_norm: Optional[int] = None,
attention_bias: bool = False,
only_cross_attention: bool = False,
double_self_attention: bool = False,
upcast_attention: bool = False,
norm_elementwise_affine: bool = True,
norm_type: str = "layer_norm", # 'layer_norm', 'ada_norm', 'ada_norm_zero', 'ada_norm_single'
norm_eps: float = 1e-5,
final_dropout: bool = False,
attention_type: str = "default",
positional_embeddings: Optional[str] = None,
num_positional_embeddings: Optional[int] = None,
attention_mode: str = "xformers",
use_rope: bool = False,
rope_scaling: Optional[Dict] = None,
compress_kv_factor: Optional[Tuple] = None,
):
super().__init__()
self.only_cross_attention = only_cross_attention
self.use_ada_layer_norm_zero = (num_embeds_ada_norm is not None) and norm_type == "ada_norm_zero"
self.use_ada_layer_norm = (num_embeds_ada_norm is not None) and norm_type == "ada_norm"
self.use_ada_layer_norm_single = norm_type == "ada_norm_single"
self.use_layer_norm = norm_type == "layer_norm"
if norm_type in ("ada_norm", "ada_norm_zero") and num_embeds_ada_norm is None:
raise ValueError(
f"`norm_type` is set to {norm_type}, but `num_embeds_ada_norm` is not defined. Please make sure to"
f" define `num_embeds_ada_norm` if setting `norm_type` to {norm_type}."
)
if positional_embeddings and (num_positional_embeddings is None):
raise ValueError(
"If `positional_embedding` type is defined, `num_positition_embeddings` must also be defined."
)
if positional_embeddings == "sinusoidal":
self.pos_embed = SinusoidalPositionalEmbedding(dim, max_seq_length=num_positional_embeddings)
else:
self.pos_embed = None
# Define 3 blocks. Each block has its own normalization layer.
# 1. Self-Attn
if self.use_ada_layer_norm:
self.norm1 = AdaLayerNorm(dim, num_embeds_ada_norm)
elif self.use_ada_layer_norm_zero:
self.norm1 = AdaLayerNormZero(dim, num_embeds_ada_norm)
else:
self.norm1 = nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
self.attn1 = Attention(
query_dim=dim,
heads=num_attention_heads,
dim_head=attention_head_dim,
dropout=dropout,
bias=attention_bias,
cross_attention_dim=cross_attention_dim if only_cross_attention else None,
upcast_attention=upcast_attention,
attention_mode=attention_mode,
use_rope=use_rope,
rope_scaling=rope_scaling,
compress_kv_factor=compress_kv_factor,
)
# 2. Cross-Attn
if cross_attention_dim is not None or double_self_attention:
# We currently only use AdaLayerNormZero for self attention where there will only be one attention block.
# I.e. the number of returned modulation chunks from AdaLayerZero would not make sense if returned during
# the second cross attention block.
self.norm2 = (
AdaLayerNorm(dim, num_embeds_ada_norm)
if self.use_ada_layer_norm
else nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
)
self.attn2 = Attention(
query_dim=dim,
cross_attention_dim=cross_attention_dim if not double_self_attention else None,
heads=num_attention_heads,
dim_head=attention_head_dim,
dropout=dropout,
bias=attention_bias,
upcast_attention=upcast_attention,
attention_mode=attention_mode, # only xformers support attention_mask
use_rope=False, # do not position in cross attention
compress_kv_factor=None,
) # is self-attn if encoder_hidden_states is none
else:
self.norm2 = None
self.attn2 = None
# 3. Feed-forward
if not self.use_ada_layer_norm_single:
self.norm3 = nn.LayerNorm(dim, elementwise_affine=norm_elementwise_affine, eps=norm_eps)
self.ff = FeedForward(
dim,
dropout=dropout,
activation_fn=activation_fn,
final_dropout=final_dropout,
)
# 4. Fuser
if attention_type == "gated" or attention_type == "gated-text-image":
self.fuser = GatedSelfAttentionDense(dim, cross_attention_dim, num_attention_heads, attention_head_dim)
# 5. Scale-shift for PixArt-Alpha.
if self.use_ada_layer_norm_single:
self.scale_shift_table = nn.Parameter(torch.randn(6, dim) / dim**0.5)
# let chunk size default to None
self._chunk_size = None
self._chunk_dim = 0
def set_chunk_feed_forward(self, chunk_size: Optional[int], dim: int = 0):
# Sets chunk feed-forward
self._chunk_size = chunk_size
self._chunk_dim = dim
def forward(
self,
hidden_states: torch.FloatTensor,
attention_mask: Optional[torch.FloatTensor] = None,
encoder_hidden_states: Optional[torch.FloatTensor] = None,
encoder_attention_mask: Optional[torch.FloatTensor] = None,
timestep: Optional[torch.LongTensor] = None,
cross_attention_kwargs: Dict[str, Any] = None,
class_labels: Optional[torch.LongTensor] = None,
position_q: Optional[torch.LongTensor] = None,
position_k: Optional[torch.LongTensor] = None,
hw: Tuple[int, int] = None,
) -> torch.FloatTensor:
# Notice that normalization is always applied before the real computation in the following blocks.
# 0. Self-Attention
batch_size = hidden_states.shape[0]
if self.use_ada_layer_norm:
norm_hidden_states = self.norm1(hidden_states, timestep)
elif self.use_ada_layer_norm_zero:
norm_hidden_states, gate_msa, shift_mlp, scale_mlp, gate_mlp = self.norm1(
hidden_states, timestep, class_labels, hidden_dtype=hidden_states.dtype
)
elif self.use_layer_norm:
norm_hidden_states = self.norm1(hidden_states)
elif self.use_ada_layer_norm_single:
shift_msa, scale_msa, gate_msa, shift_mlp, scale_mlp, gate_mlp = (
self.scale_shift_table[None] + timestep.reshape(batch_size, 6, -1)
).chunk(6, dim=1)
norm_hidden_states = self.norm1(hidden_states)
norm_hidden_states = norm_hidden_states * (1 + scale_msa) + shift_msa
norm_hidden_states = norm_hidden_states.squeeze(1)
else:
raise ValueError("Incorrect norm used")
if self.pos_embed is not None:
norm_hidden_states = self.pos_embed(norm_hidden_states)
# 1. Retrieve lora scale.
lora_scale = cross_attention_kwargs.get("scale", 1.0) if cross_attention_kwargs is not None else 1.0
# 2. Prepare GLIGEN inputs
cross_attention_kwargs = cross_attention_kwargs.copy() if cross_attention_kwargs is not None else {}
gligen_kwargs = cross_attention_kwargs.pop("gligen", None)
attn_output = self.attn1(
norm_hidden_states,
encoder_hidden_states=encoder_hidden_states if self.only_cross_attention else None,
attention_mask=attention_mask,
position_q=position_q,
position_k=position_k,
last_shape=hw,
**cross_attention_kwargs,
)
if self.use_ada_layer_norm_zero:
attn_output = gate_msa.unsqueeze(1) * attn_output
elif self.use_ada_layer_norm_single:
attn_output = gate_msa * attn_output
hidden_states = attn_output + hidden_states
if hidden_states.ndim == 4:
hidden_states = hidden_states.squeeze(1)
# 2.5 GLIGEN Control
if gligen_kwargs is not None:
hidden_states = self.fuser(hidden_states, gligen_kwargs["objs"])
# 3. Cross-Attention
if self.attn2 is not None:
if self.use_ada_layer_norm:
norm_hidden_states = self.norm2(hidden_states, timestep)
elif self.use_ada_layer_norm_zero or self.use_layer_norm:
norm_hidden_states = self.norm2(hidden_states)
elif self.use_ada_layer_norm_single:
# For PixArt norm2 isn't applied here:
# https://github.com/PixArt-alpha/PixArt-alpha/blob/0f55e922376d8b797edd44d25d0e7464b260dcab/diffusion/model/nets/PixArtMS.py#L70C1-L76C103
norm_hidden_states = hidden_states
else:
raise ValueError("Incorrect norm")
if self.pos_embed is not None and self.use_ada_layer_norm_single is False:
norm_hidden_states = self.pos_embed(norm_hidden_states)
attn_output = self.attn2(
norm_hidden_states,
encoder_hidden_states=encoder_hidden_states,
attention_mask=encoder_attention_mask,
position_q=None, # cross attn do not need relative position
position_k=None,
last_shape=None,
**cross_attention_kwargs,
)
hidden_states = attn_output + hidden_states
# 4. Feed-forward
if not self.use_ada_layer_norm_single:
norm_hidden_states = self.norm3(hidden_states)
if self.use_ada_layer_norm_zero:
norm_hidden_states = norm_hidden_states * (1 + scale_mlp[:, None]) + shift_mlp[:, None]
if self.use_ada_layer_norm_single:
norm_hidden_states = self.norm2(hidden_states)
norm_hidden_states = norm_hidden_states * (1 + scale_mlp) + shift_mlp
if self._chunk_size is not None:
# "feed_forward_chunk_size" can be used to save memory
ff_output = _chunked_feed_forward(
self.ff, norm_hidden_states, self._chunk_dim, self._chunk_size, lora_scale=lora_scale
)
else:
ff_output = self.ff(norm_hidden_states, scale=lora_scale)
if self.use_ada_layer_norm_zero:
ff_output = gate_mlp.unsqueeze(1) * ff_output
elif self.use_ada_layer_norm_single:
ff_output = gate_mlp * ff_output
hidden_states = ff_output + hidden_states
if hidden_states.ndim == 4:
hidden_states = hidden_states.squeeze(1)
return hidden_states
class AdaLayerNormSingle(nn.Module):
r"""
Norm layer adaptive layer norm single (adaLN-single).
As proposed in PixArt-Alpha (see: https://arxiv.org/abs/2310.00426; Section 2.3).
Parameters:
embedding_dim (`int`): The size of each embedding vector.
use_additional_conditions (`bool`): To use additional conditions for normalization or not.
"""
def __init__(self, embedding_dim: int, use_additional_conditions: bool = False):
super().__init__()
self.emb = CombinedTimestepSizeEmbeddings(
embedding_dim, size_emb_dim=embedding_dim // 3, use_additional_conditions=use_additional_conditions
)
self.silu = nn.SiLU()
self.linear = nn.Linear(embedding_dim, 6 * embedding_dim, bias=True)
def forward(
self,
timestep: torch.Tensor,
added_cond_kwargs: Dict[str, torch.Tensor] = None,
batch_size: int = None,
hidden_dtype: Optional[torch.dtype] = None,
) -> Tuple[torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor, torch.Tensor]:
# No modulation happening here.
embedded_timestep = self.emb(timestep, batch_size=batch_size, hidden_dtype=hidden_dtype, resolution=None,
aspect_ratio=None)
return self.linear(self.silu(embedded_timestep)), embedded_timestep
@dataclass
class Transformer3DModelOutput(BaseOutput):
"""
The output of [`Transformer2DModel`].
Args:
sample (`torch.FloatTensor` of shape `(batch_size, num_channels, height, width)` or `(batch size, num_vector_embeds - 1, num_latent_pixels)` if [`Transformer2DModel`] is discrete):
The hidden states output conditioned on the `encoder_hidden_states` input. If discrete, returns probability
distributions for the unnoised latent pixels.
"""
sample: torch.FloatTensor