pos_emb and interpolation logic

This commit is contained in:
City 2024-12-14 20:31:36 +01:00
parent fc57b98501
commit 804a7076ca
3 changed files with 39 additions and 26 deletions

View File

@ -14,7 +14,7 @@ from .blocks import (
TimestepEmbedder,
Mlp
)
from comfy.ldm.modules.diffusionmodules.mmdit import PatchEmbed
from comfy.ldm.modules.diffusionmodules.mmdit import PatchEmbed, get_1d_sincos_pos_embed_from_grid_torch
class PixArtBlock(nn.Module):
@ -134,7 +134,6 @@ class PixArt(nn.Module):
timestep = t.to(self.dtype)
y = y.to(self.dtype)
pos_embed = self.pos_embed.to(self.dtype)
self.h, self.w = x.shape[-2]//self.patch_size, x.shape[-1]//self.patch_size
x = self.x_embedder(x) + pos_embed # (N, T, D), where T = H * W / patch_size ** 2
t = self.t_embedder(timestep.to(x.dtype)) # (N, D)
t0 = self.t_block(t)
@ -193,7 +192,20 @@ class PixArt(nn.Module):
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,
# torch.linspace(-val_h + val_center, val_h + val_center, h, device=device, dtype=dtype),
# torch.linspace(-val_w + val_center, val_w + val_center, w, device=device, dtype=dtype),
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
# Unused
def get_2d_sincos_pos_embed(embed_dim, grid_size, cls_token=False, extra_tokens=0, pe_interpolation=1.0, base_size=16):
"""
grid_size: int of the grid height and width

View File

@ -5,7 +5,7 @@ import torch
import torch.nn as nn
from .blocks import t2i_modulate, CaptionEmbedder, AttentionKVCompress, MultiHeadCrossAttention, T2IFinalLayer, TimestepEmbedder, SizeEmbedder, Mlp
from .pixart import PixArt, get_2d_sincos_pos_embed
from .pixart import PixArt, get_2d_sincos_pos_embed, get_2d_sincos_pos_embed_torch
class PatchEmbed(nn.Module):
"""
@ -117,7 +117,6 @@ class PixArtMS(PixArt):
self.hidden_size = hidden_size
self.depth = depth
self.h = self.w = 0
approx_gelu = lambda: nn.GELU(approximate="tanh")
self.t_block = nn.Sequential(
nn.SiLU(),
@ -142,10 +141,10 @@ class PixArtMS(PixArt):
self.csize_embedder = SizeEmbedder(hidden_size//3, dtype=dtype, device=device, operations=operations)
self.ar_embedder = SizeEmbedder(hidden_size//3, dtype=dtype, device=device, operations=operations)
# Will use fixed sin-cos embedding:
num_patches = (input_size // patch_size) * (input_size // patch_size)
self.base_size = input_size // self.patch_size
self.register_buffer("pos_embed", torch.zeros(1, num_patches, hidden_size))
# For fixed sin-cos embedding:
# num_patches = (input_size // patch_size) * (input_size // patch_size)
# self.base_size = input_size // self.patch_size
# self.register_buffer("pos_embed", torch.zeros(1, num_patches, hidden_size))
drop_path = [x.item() for x in torch.linspace(0, drop_path, depth)] # stochastic depth decay rule
if kv_compress_config is None:
@ -157,7 +156,6 @@ class PixArtMS(PixArt):
self.blocks = nn.ModuleList([
PixArtMSBlock(
hidden_size, num_heads, mlp_ratio=mlp_ratio, drop_path=drop_path[i],
input_size=(input_size // patch_size, input_size // patch_size),
sampling=kv_compress_config['sampling'],
sr_ratio=int(kv_compress_config['scale_factor']) if i in kv_compress_config['kv_compress_layer'] else 1,
qk_norm=qk_norm,
@ -180,18 +178,22 @@ class PixArtMS(PixArt):
ar: (N, 1): aspect ratio
cs: (N ,2) size conditioning for height/width
"""
B, C, H, W = x.shape
c_res = (H + W) // 2
pe_interpolation = self.pe_interpolation
if pe_interpolation is None or self.pe_precision is not None:
# calculate pe_interpolation on-the-fly
pe_interpolation = round((x.shape[-1]+x.shape[-2])/2.0 / (512/8.0), self.pe_precision or 0)
pe_interpolation = round(c_res / (512/8.0), self.pe_precision or 0)
self.h, self.w = x.shape[-2]//self.patch_size, x.shape[-1]//self.patch_size
pos_embed = torch.from_numpy(
get_2d_sincos_pos_embed(
self.hidden_size, (self.h, self.w), pe_interpolation=pe_interpolation,
base_size=self.base_size
)
).to(device=x.device, dtype=x.dtype).unsqueeze(0)
pos_embed = get_2d_sincos_pos_embed_torch(
self.hidden_size,
h=(H // self.patch_size),
w=(W // self.patch_size),
pe_interpolation=pe_interpolation,
base_size=((round(c_res / 64) * 64) // self.patch_size),
device=x.device,
dtype=x.dtype,
).unsqueeze(0)
x = self.x_embedder(x) + pos_embed # (N, T, D), where T = H * W / patch_size ** 2
t = self.t_embedder(timestep, x.dtype) # (N, D)
@ -215,10 +217,10 @@ class PixArtMS(PixArt):
y_lens = [y.shape[2]] * y.shape[0]
y = y.squeeze(1).view(1, -1, x.shape[-1])
for block in self.blocks:
x = block(x, y, t0, y_lens, (self.h, self.w), **kwargs) # (N, T, D)
x = block(x, y, t0, y_lens, (H, W), **kwargs) # (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)
x = self.unpatchify(x, H, W) # (N, out_channels, H, W)
return x
@ -245,16 +247,18 @@ class PixArtMS(PixArt):
return out[:, :self.in_channels]
return out
def unpatchify(self, x):
def unpatchify(self, x, h, w):
"""
x: (N, T, patch_size**2 * C)
imgs: (N, H, W, C)
"""
c = self.out_channels
p = self.x_embedder.patch_size[0]
assert self.h * self.w == x.shape[1]
h = h // self.patch_size
w = w // self.patch_size
assert h * w == x.shape[1]
x = x.reshape(shape=(x.shape[0], self.h, self.w, p, p, c))
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, self.h * p, self.w * p))
imgs = x.reshape(shape=(x.shape[0], c, h * p, w * p))
return imgs

View File

@ -209,9 +209,6 @@ def detect_unet_config(state_dict, key_prefix):
if pe_key in state_dict_keys:
dit_config["input_size"] = int(math.sqrt(state_dict[pe_key].shape[1])) * patch_size
dit_config["pe_interpolation"] = dit_config["input_size"] // (512//8) # guess
else:
dit_config["input_size"] = 128 # 1024
dit_config["pe_interpolation"] = 2
ar_key = "{}ar_embedder.mlp.0.weight".format(key_prefix)
if ar_key in state_dict_keys: