Files
DiffSynth-Studio/diffsynth/models/qwen_image_vae.py
2025-11-04 10:59:29 +08:00

724 lines
24 KiB
Python

import torch
from typing import List, Optional, Tuple, Union
from torch import nn
CACHE_T = 2
class QwenImageCausalConv3d(torch.nn.Conv3d):
r"""
A custom 3D causal convolution layer with feature caching support.
This layer extends the standard Conv3D layer by ensuring causality in the time dimension and handling feature
caching for efficient inference.
Args:
in_channels (int): Number of channels in the input image
out_channels (int): Number of channels produced by the convolution
kernel_size (int or tuple): Size of the convolving kernel
stride (int or tuple, optional): Stride of the convolution. Default: 1
padding (int or tuple, optional): Zero-padding added to all three sides of the input. Default: 0
"""
def __init__(
self,
in_channels: int,
out_channels: int,
kernel_size: Union[int, Tuple[int, int, int]],
stride: Union[int, Tuple[int, int, int]] = 1,
padding: Union[int, Tuple[int, int, int]] = 0,
) -> None:
super().__init__(
in_channels=in_channels,
out_channels=out_channels,
kernel_size=kernel_size,
stride=stride,
padding=padding,
)
# Set up causal padding
self._padding = (self.padding[2], self.padding[2], self.padding[1], self.padding[1], 2 * self.padding[0], 0)
self.padding = (0, 0, 0)
def forward(self, x, cache_x=None):
padding = list(self._padding)
if cache_x is not None and self._padding[4] > 0:
cache_x = cache_x.to(x.device)
x = torch.cat([cache_x, x], dim=2)
padding[4] -= cache_x.shape[2]
x = torch.nn.functional.pad(x, padding)
return super().forward(x)
class QwenImageRMS_norm(nn.Module):
r"""
A custom RMS normalization layer.
Args:
dim (int): The number of dimensions to normalize over.
channel_first (bool, optional): Whether the input tensor has channels as the first dimension.
Default is True.
images (bool, optional): Whether the input represents image data. Default is True.
bias (bool, optional): Whether to include a learnable bias term. Default is False.
"""
def __init__(self, dim: int, channel_first: bool = True, images: bool = True, bias: bool = False) -> None:
super().__init__()
broadcastable_dims = (1, 1, 1) if not images else (1, 1)
shape = (dim, *broadcastable_dims) if channel_first else (dim,)
self.channel_first = channel_first
self.scale = dim**0.5
self.gamma = nn.Parameter(torch.ones(shape))
self.bias = nn.Parameter(torch.zeros(shape)) if bias else 0.0
def forward(self, x):
return torch.nn.functional.normalize(x, dim=(1 if self.channel_first else -1)) * self.scale * self.gamma + self.bias
class QwenImageResidualBlock(nn.Module):
r"""
A custom residual block module.
Args:
in_dim (int): Number of input channels.
out_dim (int): Number of output channels.
dropout (float, optional): Dropout rate for the dropout layer. Default is 0.0.
non_linearity (str, optional): Type of non-linearity to use. Default is "silu".
"""
def __init__(
self,
in_dim: int,
out_dim: int,
dropout: float = 0.0,
non_linearity: str = "silu",
) -> None:
super().__init__()
self.in_dim = in_dim
self.out_dim = out_dim
self.nonlinearity = torch.nn.SiLU()
# layers
self.norm1 = QwenImageRMS_norm(in_dim, images=False)
self.conv1 = QwenImageCausalConv3d(in_dim, out_dim, 3, padding=1)
self.norm2 = QwenImageRMS_norm(out_dim, images=False)
self.dropout = nn.Dropout(dropout)
self.conv2 = QwenImageCausalConv3d(out_dim, out_dim, 3, padding=1)
self.conv_shortcut = QwenImageCausalConv3d(in_dim, out_dim, 1) if in_dim != out_dim else nn.Identity()
def forward(self, x, feat_cache=None, feat_idx=[0]):
# Apply shortcut connection
h = self.conv_shortcut(x)
# First normalization and activation
x = self.norm1(x)
x = self.nonlinearity(x)
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv1(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv1(x)
# Second normalization and activation
x = self.norm2(x)
x = self.nonlinearity(x)
# Dropout
x = self.dropout(x)
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv2(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv2(x)
# Add residual connection
return x + h
class QwenImageAttentionBlock(nn.Module):
r"""
Causal self-attention with a single head.
Args:
dim (int): The number of channels in the input tensor.
"""
def __init__(self, dim):
super().__init__()
self.dim = dim
# layers
self.norm = QwenImageRMS_norm(dim)
self.to_qkv = nn.Conv2d(dim, dim * 3, 1)
self.proj = nn.Conv2d(dim, dim, 1)
def forward(self, x):
identity = x
batch_size, channels, time, height, width = x.size()
x = x.permute(0, 2, 1, 3, 4).reshape(batch_size * time, channels, height, width)
x = self.norm(x)
# compute query, key, value
qkv = self.to_qkv(x)
qkv = qkv.reshape(batch_size * time, 1, channels * 3, -1)
qkv = qkv.permute(0, 1, 3, 2).contiguous()
q, k, v = qkv.chunk(3, dim=-1)
# apply attention
x = torch.nn.functional.scaled_dot_product_attention(q, k, v)
x = x.squeeze(1).permute(0, 2, 1).reshape(batch_size * time, channels, height, width)
# output projection
x = self.proj(x)
# Reshape back: [(b*t), c, h, w] -> [b, c, t, h, w]
x = x.view(batch_size, time, channels, height, width)
x = x.permute(0, 2, 1, 3, 4)
return x + identity
class QwenImageUpsample(nn.Upsample):
r"""
Perform upsampling while ensuring the output tensor has the same data type as the input.
Args:
x (torch.Tensor): Input tensor to be upsampled.
Returns:
torch.Tensor: Upsampled tensor with the same data type as the input.
"""
def forward(self, x):
return super().forward(x.float()).type_as(x)
class QwenImageResample(nn.Module):
r"""
A custom resampling module for 2D and 3D data.
Args:
dim (int): The number of input/output channels.
mode (str): The resampling mode. Must be one of:
- 'none': No resampling (identity operation).
- 'upsample2d': 2D upsampling with nearest-exact interpolation and convolution.
- 'upsample3d': 3D upsampling with nearest-exact interpolation, convolution, and causal 3D convolution.
- 'downsample2d': 2D downsampling with zero-padding and convolution.
- 'downsample3d': 3D downsampling with zero-padding, convolution, and causal 3D convolution.
"""
def __init__(self, dim: int, mode: str) -> None:
super().__init__()
self.dim = dim
self.mode = mode
# layers
if mode == "upsample2d":
self.resample = nn.Sequential(
QwenImageUpsample(scale_factor=(2.0, 2.0), mode="nearest-exact"), nn.Conv2d(dim, dim // 2, 3, padding=1)
)
elif mode == "upsample3d":
self.resample = nn.Sequential(
QwenImageUpsample(scale_factor=(2.0, 2.0), mode="nearest-exact"), nn.Conv2d(dim, dim // 2, 3, padding=1)
)
self.time_conv = QwenImageCausalConv3d(dim, dim * 2, (3, 1, 1), padding=(1, 0, 0))
elif mode == "downsample2d":
self.resample = nn.Sequential(nn.ZeroPad2d((0, 1, 0, 1)), nn.Conv2d(dim, dim, 3, stride=(2, 2)))
elif mode == "downsample3d":
self.resample = nn.Sequential(nn.ZeroPad2d((0, 1, 0, 1)), nn.Conv2d(dim, dim, 3, stride=(2, 2)))
self.time_conv = QwenImageCausalConv3d(dim, dim, (3, 1, 1), stride=(2, 1, 1), padding=(0, 0, 0))
else:
self.resample = nn.Identity()
def forward(self, x, feat_cache=None, feat_idx=[0]):
b, c, t, h, w = x.size()
if self.mode == "upsample3d":
if feat_cache is not None:
idx = feat_idx[0]
if feat_cache[idx] is None:
feat_cache[idx] = "Rep"
feat_idx[0] += 1
else:
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None and feat_cache[idx] != "Rep":
# cache last frame of last two chunk
cache_x = torch.cat(
[feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2
)
if cache_x.shape[2] < 2 and feat_cache[idx] is not None and feat_cache[idx] == "Rep":
cache_x = torch.cat([torch.zeros_like(cache_x).to(cache_x.device), cache_x], dim=2)
if feat_cache[idx] == "Rep":
x = self.time_conv(x)
else:
x = self.time_conv(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
x = x.reshape(b, 2, c, t, h, w)
x = torch.stack((x[:, 0, :, :, :, :], x[:, 1, :, :, :, :]), 3)
x = x.reshape(b, c, t * 2, h, w)
t = x.shape[2]
x = x.permute(0, 2, 1, 3, 4).reshape(b * t, c, h, w)
x = self.resample(x)
x = x.view(b, t, x.size(1), x.size(2), x.size(3)).permute(0, 2, 1, 3, 4)
if self.mode == "downsample3d":
if feat_cache is not None:
idx = feat_idx[0]
if feat_cache[idx] is None:
feat_cache[idx] = x.clone()
feat_idx[0] += 1
else:
cache_x = x[:, :, -1:, :, :].clone()
x = self.time_conv(torch.cat([feat_cache[idx][:, :, -1:, :, :], x], 2))
feat_cache[idx] = cache_x
feat_idx[0] += 1
return x
class QwenImageMidBlock(nn.Module):
"""
Middle block for WanVAE encoder and decoder.
Args:
dim (int): Number of input/output channels.
dropout (float): Dropout rate.
non_linearity (str): Type of non-linearity to use.
"""
def __init__(self, dim: int, dropout: float = 0.0, non_linearity: str = "silu", num_layers: int = 1):
super().__init__()
self.dim = dim
# Create the components
resnets = [QwenImageResidualBlock(dim, dim, dropout, non_linearity)]
attentions = []
for _ in range(num_layers):
attentions.append(QwenImageAttentionBlock(dim))
resnets.append(QwenImageResidualBlock(dim, dim, dropout, non_linearity))
self.attentions = nn.ModuleList(attentions)
self.resnets = nn.ModuleList(resnets)
self.gradient_checkpointing = False
def forward(self, x, feat_cache=None, feat_idx=[0]):
# First residual block
x = self.resnets[0](x, feat_cache, feat_idx)
# Process through attention and residual blocks
for attn, resnet in zip(self.attentions, self.resnets[1:]):
if attn is not None:
x = attn(x)
x = resnet(x, feat_cache, feat_idx)
return x
class QwenImageEncoder3d(nn.Module):
r"""
A 3D encoder module.
Args:
dim (int): The base number of channels in the first layer.
z_dim (int): The dimensionality of the latent space.
dim_mult (list of int): Multipliers for the number of channels in each block.
num_res_blocks (int): Number of residual blocks in each block.
attn_scales (list of float): Scales at which to apply attention mechanisms.
temperal_downsample (list of bool): Whether to downsample temporally in each block.
dropout (float): Dropout rate for the dropout layers.
non_linearity (str): Type of non-linearity to use.
"""
def __init__(
self,
dim=128,
z_dim=4,
dim_mult=[1, 2, 4, 4],
num_res_blocks=2,
attn_scales=[],
temperal_downsample=[True, True, False],
dropout=0.0,
non_linearity: str = "silu",
):
super().__init__()
self.dim = dim
self.z_dim = z_dim
self.dim_mult = dim_mult
self.num_res_blocks = num_res_blocks
self.attn_scales = attn_scales
self.temperal_downsample = temperal_downsample
self.nonlinearity = torch.nn.SiLU()
# dimensions
dims = [dim * u for u in [1] + dim_mult]
scale = 1.0
# init block
self.conv_in = QwenImageCausalConv3d(3, dims[0], 3, padding=1)
# downsample blocks
self.down_blocks = torch.nn.ModuleList([])
for i, (in_dim, out_dim) in enumerate(zip(dims[:-1], dims[1:])):
# residual (+attention) blocks
for _ in range(num_res_blocks):
self.down_blocks.append(QwenImageResidualBlock(in_dim, out_dim, dropout))
if scale in attn_scales:
self.down_blocks.append(QwenImageAttentionBlock(out_dim))
in_dim = out_dim
# downsample block
if i != len(dim_mult) - 1:
mode = "downsample3d" if temperal_downsample[i] else "downsample2d"
self.down_blocks.append(QwenImageResample(out_dim, mode=mode))
scale /= 2.0
# middle blocks
self.mid_block = QwenImageMidBlock(out_dim, dropout, non_linearity, num_layers=1)
# output blocks
self.norm_out = QwenImageRMS_norm(out_dim, images=False)
self.conv_out = QwenImageCausalConv3d(out_dim, z_dim, 3, padding=1)
self.gradient_checkpointing = False
def forward(self, x, feat_cache=None, feat_idx=[0]):
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
# cache last frame of last two chunk
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv_in(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv_in(x)
## downsamples
for layer in self.down_blocks:
if feat_cache is not None:
x = layer(x, feat_cache, feat_idx)
else:
x = layer(x)
## middle
x = self.mid_block(x, feat_cache, feat_idx)
## head
x = self.norm_out(x)
x = self.nonlinearity(x)
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
# cache last frame of last two chunk
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv_out(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv_out(x)
return x
class QwenImageUpBlock(nn.Module):
"""
A block that handles upsampling for the WanVAE decoder.
Args:
in_dim (int): Input dimension
out_dim (int): Output dimension
num_res_blocks (int): Number of residual blocks
dropout (float): Dropout rate
upsample_mode (str, optional): Mode for upsampling ('upsample2d' or 'upsample3d')
non_linearity (str): Type of non-linearity to use
"""
def __init__(
self,
in_dim: int,
out_dim: int,
num_res_blocks: int,
dropout: float = 0.0,
upsample_mode: Optional[str] = None,
non_linearity: str = "silu",
):
super().__init__()
self.in_dim = in_dim
self.out_dim = out_dim
# Create layers list
resnets = []
# Add residual blocks and attention if needed
current_dim = in_dim
for _ in range(num_res_blocks + 1):
resnets.append(QwenImageResidualBlock(current_dim, out_dim, dropout, non_linearity))
current_dim = out_dim
self.resnets = nn.ModuleList(resnets)
# Add upsampling layer if needed
self.upsamplers = None
if upsample_mode is not None:
self.upsamplers = nn.ModuleList([QwenImageResample(out_dim, mode=upsample_mode)])
self.gradient_checkpointing = False
def forward(self, x, feat_cache=None, feat_idx=[0]):
"""
Forward pass through the upsampling block.
Args:
x (torch.Tensor): Input tensor
feat_cache (list, optional): Feature cache for causal convolutions
feat_idx (list, optional): Feature index for cache management
Returns:
torch.Tensor: Output tensor
"""
for resnet in self.resnets:
if feat_cache is not None:
x = resnet(x, feat_cache, feat_idx)
else:
x = resnet(x)
if self.upsamplers is not None:
if feat_cache is not None:
x = self.upsamplers[0](x, feat_cache, feat_idx)
else:
x = self.upsamplers[0](x)
return x
class QwenImageDecoder3d(nn.Module):
r"""
A 3D decoder module.
Args:
dim (int): The base number of channels in the first layer.
z_dim (int): The dimensionality of the latent space.
dim_mult (list of int): Multipliers for the number of channels in each block.
num_res_blocks (int): Number of residual blocks in each block.
attn_scales (list of float): Scales at which to apply attention mechanisms.
temperal_upsample (list of bool): Whether to upsample temporally in each block.
dropout (float): Dropout rate for the dropout layers.
non_linearity (str): Type of non-linearity to use.
"""
def __init__(
self,
dim=128,
z_dim=4,
dim_mult=[1, 2, 4, 4],
num_res_blocks=2,
attn_scales=[],
temperal_upsample=[False, True, True],
dropout=0.0,
non_linearity: str = "silu",
):
super().__init__()
self.dim = dim
self.z_dim = z_dim
self.dim_mult = dim_mult
self.num_res_blocks = num_res_blocks
self.attn_scales = attn_scales
self.temperal_upsample = temperal_upsample
self.nonlinearity = torch.nn.SiLU()
# dimensions
dims = [dim * u for u in [dim_mult[-1]] + dim_mult[::-1]]
scale = 1.0 / 2 ** (len(dim_mult) - 2)
# init block
self.conv_in = QwenImageCausalConv3d(z_dim, dims[0], 3, padding=1)
# middle blocks
self.mid_block = QwenImageMidBlock(dims[0], dropout, non_linearity, num_layers=1)
# upsample blocks
self.up_blocks = nn.ModuleList([])
for i, (in_dim, out_dim) in enumerate(zip(dims[:-1], dims[1:])):
# residual (+attention) blocks
if i > 0:
in_dim = in_dim // 2
# Determine if we need upsampling
upsample_mode = None
if i != len(dim_mult) - 1:
upsample_mode = "upsample3d" if temperal_upsample[i] else "upsample2d"
# Create and add the upsampling block
up_block = QwenImageUpBlock(
in_dim=in_dim,
out_dim=out_dim,
num_res_blocks=num_res_blocks,
dropout=dropout,
upsample_mode=upsample_mode,
non_linearity=non_linearity,
)
self.up_blocks.append(up_block)
# Update scale for next iteration
if upsample_mode is not None:
scale *= 2.0
# output blocks
self.norm_out = QwenImageRMS_norm(out_dim, images=False)
self.conv_out = QwenImageCausalConv3d(out_dim, 3, 3, padding=1)
self.gradient_checkpointing = False
def forward(self, x, feat_cache=None, feat_idx=[0]):
## conv1
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
# cache last frame of last two chunk
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv_in(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv_in(x)
## middle
x = self.mid_block(x, feat_cache, feat_idx)
## upsamples
for up_block in self.up_blocks:
x = up_block(x, feat_cache, feat_idx)
## head
x = self.norm_out(x)
x = self.nonlinearity(x)
if feat_cache is not None:
idx = feat_idx[0]
cache_x = x[:, :, -CACHE_T:, :, :].clone()
if cache_x.shape[2] < 2 and feat_cache[idx] is not None:
# cache last frame of last two chunk
cache_x = torch.cat([feat_cache[idx][:, :, -1, :, :].unsqueeze(2).to(cache_x.device), cache_x], dim=2)
x = self.conv_out(x, feat_cache[idx])
feat_cache[idx] = cache_x
feat_idx[0] += 1
else:
x = self.conv_out(x)
return x
class QwenImageVAE(torch.nn.Module):
def __init__(
self,
base_dim: int = 96,
z_dim: int = 16,
dim_mult: Tuple[int] = [1, 2, 4, 4],
num_res_blocks: int = 2,
attn_scales: List[float] = [],
temperal_downsample: List[bool] = [False, True, True],
dropout: float = 0.0,
) -> None:
super().__init__()
self.z_dim = z_dim
self.temperal_downsample = temperal_downsample
self.temperal_upsample = temperal_downsample[::-1]
self.encoder = QwenImageEncoder3d(
base_dim, z_dim * 2, dim_mult, num_res_blocks, attn_scales, self.temperal_downsample, dropout
)
self.quant_conv = QwenImageCausalConv3d(z_dim * 2, z_dim * 2, 1)
self.post_quant_conv = QwenImageCausalConv3d(z_dim, z_dim, 1)
self.decoder = QwenImageDecoder3d(
base_dim, z_dim, dim_mult, num_res_blocks, attn_scales, self.temperal_upsample, dropout
)
mean = [
-0.7571,
-0.7089,
-0.9113,
0.1075,
-0.1745,
0.9653,
-0.1517,
1.5508,
0.4134,
-0.0715,
0.5517,
-0.3632,
-0.1922,
-0.9497,
0.2503,
-0.2921,
]
std = [
2.8184,
1.4541,
2.3275,
2.6558,
1.2196,
1.7708,
2.6052,
2.0743,
3.2687,
2.1526,
2.8652,
1.5579,
1.6382,
1.1253,
2.8251,
1.9160,
]
self.mean = torch.tensor(mean).view(1, 16, 1, 1, 1)
self.std = 1 / torch.tensor(std).view(1, 16, 1, 1, 1)
def encode(self, x, **kwargs):
x = x.unsqueeze(2)
x = self.encoder(x)
x = self.quant_conv(x)
x = x[:, :16]
mean, std = self.mean.to(dtype=x.dtype, device=x.device), self.std.to(dtype=x.dtype, device=x.device)
x = (x - mean) * std
x = x.squeeze(2)
return x
def decode(self, x, **kwargs):
x = x.unsqueeze(2)
mean, std = self.mean.to(dtype=x.dtype, device=x.device), self.std.to(dtype=x.dtype, device=x.device)
x = x / std + mean
x = self.post_quant_conv(x)
x = self.decoder(x)
x = x.squeeze(2)
return x