Remove some useless code.

This commit is contained in:
comfyanonymous 2024-12-20 17:43:50 -05:00
parent e946667216
commit b5fe39211a
2 changed files with 13 additions and 199 deletions

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@ -1,196 +0,0 @@
# Based on:
# https://github.com/PixArt-alpha/PixArt-alpha [Apache 2.0 license]
# https://github.com/PixArt-alpha/PixArt-sigma [Apache 2.0 license]
import torch
import torch.nn as nn
from .blocks import (
t2i_modulate,
CaptionEmbedder,
AttentionKVCompress,
MultiHeadCrossAttention,
T2IFinalLayer,
)
from comfy.ldm.modules.diffusionmodules.mmdit import PatchEmbed, TimestepEmbedder, Mlp, get_1d_sincos_pos_embed_from_grid_torch
class PixArtBlock(nn.Module):
"""
A PixArt block with adaptive layer norm (adaLN-single) conditioning.
"""
def __init__(self, hidden_size, num_heads, mlp_ratio=4.0, drop_path=0, input_size=None, sampling=None, sr_ratio=1, qk_norm=False, **block_kwargs):
super().__init__()
self.norm1 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6)
self.attn = AttentionKVCompress(
hidden_size, num_heads=num_heads, qkv_bias=True, sampling=sampling, sr_ratio=sr_ratio,
qk_norm=qk_norm, **block_kwargs
)
self.cross_attn = MultiHeadCrossAttention(hidden_size, num_heads, **block_kwargs)
self.norm2 = nn.LayerNorm(hidden_size, elementwise_affine=False, eps=1e-6)
# to be compatible with lower version pytorch
approx_gelu = lambda: nn.GELU(approximate="tanh")
self.mlp = Mlp(in_features=hidden_size, hidden_features=int(hidden_size * mlp_ratio), act_layer=approx_gelu, drop=0)
self.drop_path = nn.Identity() #DropPath(drop_path) if drop_path > 0. else nn.Identity()
self.scale_shift_table = nn.Parameter(torch.randn(6, hidden_size) / hidden_size ** 0.5)
self.sampling = sampling
self.sr_ratio = sr_ratio
def forward(self, x, y, t, mask=None, **kwargs):
B, N, C = x.shape
shift_msa, scale_msa, gate_msa, shift_mlp, scale_mlp, gate_mlp = (self.scale_shift_table[None] + t.reshape(B, 6, -1)).chunk(6, dim=1)
x = x + self.drop_path(gate_msa * self.attn(t2i_modulate(self.norm1(x), shift_msa, scale_msa)).reshape(B, N, C))
x = x + self.cross_attn(x, y, mask)
x = x + self.drop_path(gate_mlp * self.mlp(t2i_modulate(self.norm2(x), shift_mlp, scale_mlp)))
return x
### Core PixArt Model ###
class PixArt(nn.Module):
"""
Diffusion model with a Transformer backbone.
"""
def __init__(
self,
input_size=32,
patch_size=2,
in_channels=4,
hidden_size=1152,
depth=28,
num_heads=16,
mlp_ratio=4.0,
class_dropout_prob=0.1,
pred_sigma=True,
drop_path: float = 0.,
caption_channels=4096,
pe_interpolation=1.0,
pe_precision=None,
config=None,
model_max_length=120,
qk_norm=False,
kv_compress_config=None,
**kwargs,
):
super().__init__()
self.pred_sigma = pred_sigma
self.in_channels = in_channels
self.out_channels = in_channels * 2 if pred_sigma else in_channels
self.patch_size = patch_size
self.num_heads = num_heads
self.pe_interpolation = pe_interpolation
self.pe_precision = pe_precision
self.depth = depth
self.x_embedder = PatchEmbed(input_size, patch_size, in_channels, hidden_size, bias=True)
self.t_embedder = TimestepEmbedder(hidden_size)
num_patches = self.x_embedder.num_patches
self.base_size = input_size // self.patch_size
# Will use fixed sin-cos embedding:
self.register_buffer("pos_embed", torch.zeros(1, num_patches, hidden_size))
approx_gelu = lambda: nn.GELU(approximate="tanh")
self.t_block = nn.Sequential(
nn.SiLU(),
nn.Linear(hidden_size, 6 * hidden_size, bias=True)
)
self.y_embedder = CaptionEmbedder(
in_channels=caption_channels, hidden_size=hidden_size, uncond_prob=class_dropout_prob,
act_layer=approx_gelu, token_num=model_max_length
)
drop_path = [x.item() for x in torch.linspace(0, drop_path, depth)] # stochastic depth decay rule
self.kv_compress_config = kv_compress_config
if kv_compress_config is None:
self.kv_compress_config = {
'sampling': None,
'scale_factor': 1,
'kv_compress_layer': [],
}
self.blocks = nn.ModuleList([
PixArtBlock(
hidden_size, num_heads, mlp_ratio=mlp_ratio, drop_path=drop_path[i],
input_size=(input_size // patch_size, input_size // patch_size),
sampling=self.kv_compress_config['sampling'],
sr_ratio=int(
self.kv_compress_config['scale_factor']
) if i in self.kv_compress_config['kv_compress_layer'] else 1,
qk_norm=qk_norm,
)
for i in range(depth)
])
self.final_layer = T2IFinalLayer(hidden_size, patch_size, self.out_channels)
def forward_raw(self, x, t, y, mask=None, data_info=None):
"""
Original forward pass of PixArt.
x: (N, C, H, W) tensor of spatial inputs (images or latent representations of images)
t: (N,) tensor of diffusion timesteps
y: (N, 1, 120, C) tensor of class labels
"""
x = self.x_embedder(x) + pos_embed # (N, T, D), where T = H * W / patch_size ** 2
t = self.t_embedder(timestep) # (N, D)
t0 = self.t_block(t)
y = self.y_embedder(y, self.training) # (N, 1, L, D)
if mask is not None:
if mask.shape[0] != y.shape[0]:
mask = mask.repeat(y.shape[0] // mask.shape[0], 1)
mask = mask.squeeze(1).squeeze(1)
y = y.squeeze(1).masked_select(mask.unsqueeze(-1) != 0).view(1, -1, x.shape[-1])
y_lens = mask.sum(dim=1).tolist()
else:
y_lens = None
y = y.squeeze(1).view(1, -1, x.shape[-1])
for block in self.blocks:
x = block(x, y, t0, y_lens) # (N, T, D)
x = self.final_layer(x, t) # (N, T, patch_size ** 2 * out_channels)
x = self.unpatchify(x) # (N, out_channels, H, W)
return x
def forward(self, x, timesteps, context, y=None, **kwargs):
"""
Forward pass that adapts comfy input to original forward function
x: (N, C, H, W) tensor of spatial inputs (images or latent representations of images)
timesteps: (N,) tensor of diffusion timesteps
context: (N, 1, 120, C) conditioning
y: extra conditioning.
"""
## Still accepts the input w/o that dim but returns garbage
if len(context.shape) == 3:
context = context.unsqueeze(1)
## run original forward pass
out = self.forward_raw(
x = x,
t = timesteps,
y = context,
)
## only return EPS
eps, _ = out[:, :self.in_channels], out[:, self.in_channels:]
return eps
def unpatchify(self, x):
"""
x: (N, T, patch_size**2 * C)
imgs: (N, H, W, C)
"""
c = self.out_channels
p = self.x_embedder.patch_size[0]
h = w = int(x.shape[1] ** 0.5)
assert h * w == x.shape[1]
x = x.reshape(shape=(x.shape[0], h, w, p, p, c))
x = torch.einsum('nhwpqc->nchpwq', x)
imgs = x.reshape(shape=(x.shape[0], c, h * p, h * p))
return imgs
def get_2d_sincos_pos_embed_torch(embed_dim, w, h, pe_interpolation=1.0, base_size=16, device=None, dtype=torch.float32):
grid_h, grid_w = torch.meshgrid(
torch.arange(h, device=device, dtype=dtype) / (h/base_size) / pe_interpolation,
torch.arange(w, device=device, dtype=dtype) / (w/base_size) / pe_interpolation,
indexing='ij'
)
emb_h = get_1d_sincos_pos_embed_from_grid_torch(embed_dim // 2, grid_h, device=device, dtype=dtype)
emb_w = get_1d_sincos_pos_embed_from_grid_torch(embed_dim // 2, grid_w, device=device, dtype=dtype)
emb = torch.cat([emb_w, emb_h], dim=1) # (H*W, D)
return emb

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@ -12,10 +12,20 @@ from .blocks import (
T2IFinalLayer, T2IFinalLayer,
SizeEmbedder, SizeEmbedder,
) )
from comfy.ldm.modules.diffusionmodules.mmdit import TimestepEmbedder, PatchEmbed, Mlp from comfy.ldm.modules.diffusionmodules.mmdit import TimestepEmbedder, PatchEmbed, Mlp, get_1d_sincos_pos_embed_from_grid_torch
from .pixart import PixArt, get_2d_sincos_pos_embed_torch
def get_2d_sincos_pos_embed_torch(embed_dim, w, h, pe_interpolation=1.0, base_size=16, device=None, dtype=torch.float32):
grid_h, grid_w = torch.meshgrid(
torch.arange(h, device=device, dtype=dtype) / (h/base_size) / pe_interpolation,
torch.arange(w, device=device, dtype=dtype) / (w/base_size) / pe_interpolation,
indexing='ij'
)
emb_h = get_1d_sincos_pos_embed_from_grid_torch(embed_dim // 2, grid_h, device=device, dtype=dtype)
emb_w = get_1d_sincos_pos_embed_from_grid_torch(embed_dim // 2, grid_w, device=device, dtype=dtype)
emb = torch.cat([emb_w, emb_h], dim=1) # (H*W, D)
return emb
class PixArtMSBlock(nn.Module): class PixArtMSBlock(nn.Module):
""" """
A PixArt block with adaptive layer norm zero (adaLN-Zero) conditioning. A PixArt block with adaptive layer norm zero (adaLN-Zero) conditioning.
@ -53,7 +63,7 @@ class PixArtMSBlock(nn.Module):
### Core PixArt Model ### ### Core PixArt Model ###
class PixArtMS(PixArt): class PixArtMS(nn.Module):
""" """
Diffusion model with a Transformer backbone. Diffusion model with a Transformer backbone.
""" """