Files
logtd-ComfyUI-FLATTEN/modules/unet.py
T
2024-02-25 19:38:43 -07:00

531 lines
22 KiB
Python

from .resnet_block3d import ResnetBlock3D
from .downsample3d import Downsample3D
from .upsample3d import Upsample3D
from .convs import InflatedConv3d
from .transformer3d import Transformer3DModel
import torch as th
import torch.nn as nn
from comfy.ldm.modules.diffusionmodules.util import (
zero_module,
timestep_embedding,
)
from comfy.ldm.util import exists
from comfy.ldm.modules.diffusionmodules.openaimodel import TimestepBlock, apply_control
import comfy.ops
ops = comfy.ops.disable_weight_init
def forward_timestep_embed(ts, x, emb, context=None, transformer_options={}, output_shape=None, time_context=None, num_video_frames=None, image_only_indicator=None):
for layer in ts:
if isinstance(layer, TimestepBlock) or isinstance(layer, ResnetBlock3D):
x = layer(x, emb)
elif isinstance(layer, Transformer3DModel):
x = layer(x, context, transformer_options)
if "transformer_index" in transformer_options:
transformer_options["transformer_index"] += 1
elif isinstance(layer, Upsample3D):
x = layer(x, output_shape=output_shape)
else:
x = layer(x)
return x
class TimestepEmbedSequential(nn.Sequential, TimestepBlock):
"""
A sequential module that passes timestep embeddings to the children that
support it as an extra input.
"""
def forward(self, *args, **kwargs):
return forward_timestep_embed(self, *args, **kwargs)
class UNetModel(nn.Module):
"""
The full UNet model with attention and timestep embedding.
:param in_channels: channels in the input Tensor.
:param model_channels: base channel count for the model.
:param out_channels: channels in the output Tensor.
:param num_res_blocks: number of residual blocks per downsample.
:param dropout: the dropout probability.
:param channel_mult: channel multiplier for each level of the UNet.
:param conv_resample: if True, use learned convolutions for upsampling and
downsampling.
:param dims: determines if the signal is 1D, 2D, or 3D.
:param num_classes: if specified (as an int), then this model will be
class-conditional with `num_classes` classes.
:param use_checkpoint: use gradient checkpointing to reduce memory usage.
:param num_heads: the number of attention heads in each attention layer.
:param num_heads_channels: if specified, ignore num_heads and instead use
a fixed channel width per attention head.
:param num_heads_upsample: works with num_heads to set a different number
of heads for upsampling. Deprecated.
:param use_scale_shift_norm: use a FiLM-like conditioning mechanism.
:param resblock_updown: use residual blocks for up/downsampling.
:param use_new_attention_order: use a different attention pattern for potentially
increased efficiency.
"""
def __init__(
self,
image_size,
in_channels,
model_channels,
out_channels,
num_res_blocks,
dropout=0,
channel_mult=(1, 2, 4, 8),
conv_resample=True,
dims=2,
num_classes=None,
use_checkpoint=False,
dtype=th.float32,
num_heads=-1,
num_head_channels=-1,
num_heads_upsample=-1,
use_scale_shift_norm=False,
resblock_updown=False,
use_new_attention_order=False,
use_spatial_transformer=False, # custom transformer support
transformer_depth=1, # custom transformer support
context_dim=None, # custom transformer support
# custom support for prediction of discrete ids into codebook of first stage vq model
n_embed=None,
legacy=True,
disable_self_attentions=None,
num_attention_blocks=None,
disable_middle_self_attn=False,
use_linear_in_transformer=False,
adm_in_channels=None,
transformer_depth_middle=None,
transformer_depth_output=None,
use_temporal_resblock=False,
use_temporal_attention=False,
time_context_dim=None,
extra_ff_mix_layer=False,
use_spatial_context=False,
merge_strategy=None,
merge_factor=0.0,
video_kernel_size=None,
disable_temporal_crossattention=False,
max_ddpm_temb_period=10000,
device=None,
operations=ops,
):
super().__init__()
if context_dim is not None:
assert use_spatial_transformer, 'You forgot to use the spatial transformer for your cross-attention conditioning...'
if num_heads_upsample == -1:
num_heads_upsample = num_heads
if num_heads == -1:
assert num_head_channels != -1, 'Either num_heads or num_head_channels has to be set'
if num_head_channels == -1:
assert num_heads != -1, 'Either num_heads or num_head_channels has to be set'
self.in_channels = in_channels
self.model_channels = model_channels
self.out_channels = out_channels
if isinstance(num_res_blocks, int):
self.num_res_blocks = len(channel_mult) * [num_res_blocks]
else:
if len(num_res_blocks) != len(channel_mult):
raise ValueError("provide num_res_blocks either as an int (globally constant) or "
"as a list/tuple (per-level) with the same length as channel_mult")
self.num_res_blocks = num_res_blocks
if disable_self_attentions is not None:
# should be a list of booleans, indicating whether to disable self-attention in TransformerBlocks or not
assert len(disable_self_attentions) == len(channel_mult)
if num_attention_blocks is not None:
assert len(num_attention_blocks) == len(self.num_res_blocks)
transformer_depth = transformer_depth[:]
transformer_depth_output = transformer_depth_output[:]
self.dropout = dropout
self.channel_mult = channel_mult
self.conv_resample = conv_resample
self.num_classes = num_classes
self.use_checkpoint = use_checkpoint
self.dtype = dtype
self.num_heads = num_heads
self.num_head_channels = num_head_channels
self.num_heads_upsample = num_heads_upsample
self.use_temporal_resblocks = use_temporal_resblock
self.predict_codebook_ids = n_embed is not None
self.default_num_video_frames = None
self.default_image_only_indicator = None
time_embed_dim = model_channels * 4
self.time_embed = nn.Sequential(
operations.Linear(model_channels, time_embed_dim,
dtype=self.dtype, device=device),
nn.SiLU(),
operations.Linear(time_embed_dim, time_embed_dim,
dtype=self.dtype, device=device),
)
if self.num_classes is not None:
if isinstance(self.num_classes, int):
self.label_emb = nn.Embedding(
num_classes, time_embed_dim, dtype=self.dtype, device=device)
elif self.num_classes == "continuous":
print("setting up linear c_adm embedding layer")
self.label_emb = nn.Linear(1, time_embed_dim)
elif self.num_classes == "sequential":
assert adm_in_channels is not None
self.label_emb = nn.Sequential(
nn.Sequential(
operations.Linear(
adm_in_channels, time_embed_dim, dtype=self.dtype, device=device),
nn.SiLU(),
operations.Linear(
time_embed_dim, time_embed_dim, dtype=self.dtype, device=device),
)
)
else:
raise ValueError()
self.input_blocks = nn.ModuleList(
[
TimestepEmbedSequential(
InflatedConv3d(
in_channels, model_channels, kernel_size=3, padding=(1, 1))
).half()
]
)
self._feature_size = model_channels
input_block_chans = [model_channels]
ch = model_channels
ds = 1
def get_attention_layer(
ch,
num_heads,
dim_head,
depth=1,
context_dim=None,
use_checkpoint=False,
disable_self_attn=False,
):
return Transformer3DModel(
ch, num_heads, dim_head, depth=depth, context_dim=context_dim,
disable_self_attn=disable_self_attn, use_linear=use_linear_in_transformer,
use_checkpoint=use_checkpoint, dtype=self.dtype, device=device, operations=operations
)
def get_resblock(
ch,
time_embed_dim,
dropout,
out_channels,
dims,
use_checkpoint,
use_scale_shift_norm,
down=False,
up=False,
dtype=None,
device=None,
operations=ops
):
return ResnetBlock3D(
channels=ch,
emb_channels=time_embed_dim,
dropout=dropout,
out_channels=out_channels,
use_checkpoint=use_checkpoint,
dims=dims,
use_scale_shift_norm=use_scale_shift_norm,
down=down,
up=up,
dtype=dtype,
device=device,
operations=operations
)
for level, mult in enumerate(channel_mult):
for nr in range(self.num_res_blocks[level]):
layers = [
get_resblock(
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=mult * model_channels,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations,
)
]
ch = mult * model_channels
num_transformers = transformer_depth.pop(0)
if num_transformers > 0:
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
# num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
if exists(disable_self_attentions):
disabled_sa = disable_self_attentions[level]
else:
disabled_sa = False
if not exists(num_attention_blocks) or nr < num_attention_blocks[level]:
layers.append(get_attention_layer(
ch, num_heads, dim_head, depth=num_transformers, context_dim=context_dim,
disable_self_attn=disabled_sa, use_checkpoint=use_checkpoint)
)
self.input_blocks.append(TimestepEmbedSequential(*layers))
self._feature_size += ch
input_block_chans.append(ch)
if level != len(channel_mult) - 1:
out_ch = ch
self.input_blocks.append(
TimestepEmbedSequential(
get_resblock(
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=out_ch,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
down=True,
dtype=self.dtype,
device=device,
operations=operations
)
if resblock_updown
else Downsample3D(
ch, conv_resample, dims=dims, out_channels=out_ch, dtype=self.dtype, device=device, operations=operations
)
)
)
ch = out_ch
input_block_chans.append(ch)
ds *= 2
self._feature_size += ch
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
# num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
mid_block = [
get_resblock(
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=None,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)]
if transformer_depth_middle >= 0:
mid_block += [get_attention_layer( # always uses a self-attn
ch, num_heads, dim_head, depth=transformer_depth_middle, context_dim=context_dim,
disable_self_attn=disable_middle_self_attn, use_checkpoint=use_checkpoint
),
get_resblock(
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=None,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)]
self.middle_block = TimestepEmbedSequential(*mid_block)
self._feature_size += ch
self.num_upsamplers = 0
self.output_blocks = nn.ModuleList([])
for level, mult in list(enumerate(channel_mult))[::-1]:
for i in range(self.num_res_blocks[level] + 1):
ich = input_block_chans.pop()
layers = [
get_resblock(
ch=ch + ich,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=model_channels * mult,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
dtype=self.dtype,
device=device,
operations=operations
)
]
ch = model_channels * mult
num_transformers = transformer_depth_output.pop()
if num_transformers > 0:
if num_head_channels == -1:
dim_head = ch // num_heads
else:
num_heads = ch // num_head_channels
dim_head = num_head_channels
if legacy:
# num_heads = 1
dim_head = ch // num_heads if use_spatial_transformer else num_head_channels
if exists(disable_self_attentions):
disabled_sa = disable_self_attentions[level]
else:
disabled_sa = False
if not exists(num_attention_blocks) or i < num_attention_blocks[level]:
layers.append(
get_attention_layer(
ch, num_heads, dim_head, depth=num_transformers, context_dim=context_dim,
disable_self_attn=disabled_sa, use_checkpoint=use_checkpoint
)
)
if level and i == self.num_res_blocks[level]:
out_ch = ch
layers.append(
get_resblock(
ch=ch,
time_embed_dim=time_embed_dim,
dropout=dropout,
out_channels=out_ch,
dims=dims,
use_checkpoint=use_checkpoint,
use_scale_shift_norm=use_scale_shift_norm,
up=True,
dtype=self.dtype,
device=device,
operations=operations
)
if resblock_updown
else Upsample3D(ch, conv_resample, dims=dims, out_channels=out_ch, dtype=self.dtype, device=device, operations=operations)
)
if not resblock_updown:
self.num_upsamplers += 1
ds //= 2
self.output_blocks.append(TimestepEmbedSequential(*layers))
self._feature_size += ch
self.out = nn.Sequential(
operations.GroupNorm(32, ch, dtype=self.dtype, device=device),
nn.SiLU(),
zero_module(InflatedConv3d(model_channels,
out_channels, 3, padding=1, dtype=self.dtype, device=device).half()),
)
if self.predict_codebook_ids:
self.id_predictor = nn.Sequential(
operations.GroupNorm(32, ch, dtype=self.dtype, device=device),
InflatedConv3d(model_channels, n_embed,
1, dtype=self.dtype, device=device).half(),
# nn.LogSoftmax(dim=1) # change to cross_entropy and produce non-normalized logits
)
def forward(self, x, timesteps=None, context=None, y=None, control=None, transformer_options={}, **kwargs):
"""
Apply the model to an input batch.
:param x: an [N x C x ...] Tensor of inputs.
:param timesteps: a 1-D batch of timesteps.
:param context: conditioning plugged in via crossattn
:param y: an [N] Tensor of labels, if class-conditional.
:return: an [N x C x ...] Tensor of outputs.
"""
default_overall_up_factor = 2**self.num_upsamplers
forward_upsample_size = False
upsample_size = None
if any(s % default_overall_up_factor != 0 for s in x.shape[-2:]):
print('Upsampling True')
forward_upsample_size = True
transformer_options["original_shape"] = list(x.shape)
transformer_options["transformer_index"] = 0
transformer_patches = transformer_options.get("patches", {})
num_video_frames = kwargs.get(
"num_video_frames", self.default_num_video_frames)
image_only_indicator = kwargs.get(
"image_only_indicator", self.default_image_only_indicator)
time_context = kwargs.get("time_context", None)
assert (y is not None) == (
self.num_classes is not None
), "must specify y if and only if the model is class-conditional"
hs = []
t_emb = timestep_embedding(
timesteps, self.model_channels, repeat_only=False).to(x.dtype)
emb = self.time_embed(t_emb)
if self.num_classes is not None:
assert y.shape[0] == x.shape[0]
emb = emb + self.label_emb(y)
h = x
for id, module in enumerate(self.input_blocks):
transformer_options["block"] = ("input", id)
h = forward_timestep_embed(module, h, emb, context, transformer_options, time_context=time_context,
num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = apply_control(h, control, 'input')
if "input_block_patch" in transformer_patches:
patch = transformer_patches["input_block_patch"]
for p in patch:
h = p(h, transformer_options)
hs.append(h)
if "input_block_patch_after_skip" in transformer_patches:
patch = transformer_patches["input_block_patch_after_skip"]
for p in patch:
h = p(h, transformer_options)
transformer_options["block"] = ("middle", 0)
h = forward_timestep_embed(self.middle_block, h, emb, context, transformer_options, time_context=time_context,
num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = apply_control(h, control, 'middle')
for id, module in enumerate(self.output_blocks):
transformer_options["block"] = ("output", id)
hsp = hs.pop()
hsp = apply_control(hsp, control, 'output')
if "output_block_patch" in transformer_patches:
patch = transformer_patches["output_block_patch"]
for p in patch:
h, hsp = p(h, hsp, transformer_options)
h = th.cat([h, hsp], dim=1)
del hsp
if len(hs) > 0 and forward_upsample_size:
output_shape = hs[-1].shape[2:]
else:
output_shape = None
h = forward_timestep_embed(module, h, emb, context, transformer_options, output_shape,
time_context=time_context, num_video_frames=num_video_frames, image_only_indicator=image_only_indicator)
h = h.type(x.dtype)
if self.predict_codebook_ids:
return self.id_predictor(h)
else:
return self.out(h)