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-rw-r--r--ldm/modules/diffusionmodules/__init__.py0
-rw-r--r--ldm/modules/diffusionmodules/model.py835
-rw-r--r--ldm/modules/diffusionmodules/openaimodel.py961
-rw-r--r--ldm/modules/diffusionmodules/util.py267
4 files changed, 0 insertions, 2063 deletions
diff --git a/ldm/modules/diffusionmodules/__init__.py b/ldm/modules/diffusionmodules/__init__.py
deleted file mode 100644
index e69de29b..00000000
--- a/ldm/modules/diffusionmodules/__init__.py
+++ /dev/null
diff --git a/ldm/modules/diffusionmodules/model.py b/ldm/modules/diffusionmodules/model.py
deleted file mode 100644
index 533e589a..00000000
--- a/ldm/modules/diffusionmodules/model.py
+++ /dev/null
@@ -1,835 +0,0 @@
-# pytorch_diffusion + derived encoder decoder
-import math
-import torch
-import torch.nn as nn
-import numpy as np
-from einops import rearrange
-
-from ldm.util import instantiate_from_config
-from ldm.modules.attention import LinearAttention
-
-
-def get_timestep_embedding(timesteps, embedding_dim):
- """
- This matches the implementation in Denoising Diffusion Probabilistic Models:
- From Fairseq.
- Build sinusoidal embeddings.
- This matches the implementation in tensor2tensor, but differs slightly
- from the description in Section 3.5 of "Attention Is All You Need".
- """
- assert len(timesteps.shape) == 1
-
- half_dim = embedding_dim // 2
- emb = math.log(10000) / (half_dim - 1)
- emb = torch.exp(torch.arange(half_dim, dtype=torch.float32) * -emb)
- emb = emb.to(device=timesteps.device)
- emb = timesteps.float()[:, None] * emb[None, :]
- emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1)
- if embedding_dim % 2 == 1: # zero pad
- emb = torch.nn.functional.pad(emb, (0,1,0,0))
- return emb
-
-
-def nonlinearity(x):
- # swish
- return x*torch.sigmoid(x)
-
-
-def Normalize(in_channels, num_groups=32):
- return torch.nn.GroupNorm(num_groups=num_groups, num_channels=in_channels, eps=1e-6, affine=True)
-
-
-class Upsample(nn.Module):
- def __init__(self, in_channels, with_conv):
- super().__init__()
- self.with_conv = with_conv
- if self.with_conv:
- self.conv = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, x):
- x = torch.nn.functional.interpolate(x, scale_factor=2.0, mode="nearest")
- if self.with_conv:
- x = self.conv(x)
- return x
-
-
-class Downsample(nn.Module):
- def __init__(self, in_channels, with_conv):
- super().__init__()
- self.with_conv = with_conv
- if self.with_conv:
- # no asymmetric padding in torch conv, must do it ourselves
- self.conv = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=3,
- stride=2,
- padding=0)
-
- def forward(self, x):
- if self.with_conv:
- pad = (0,1,0,1)
- x = torch.nn.functional.pad(x, pad, mode="constant", value=0)
- x = self.conv(x)
- else:
- x = torch.nn.functional.avg_pool2d(x, kernel_size=2, stride=2)
- return x
-
-
-class ResnetBlock(nn.Module):
- def __init__(self, *, in_channels, out_channels=None, conv_shortcut=False,
- dropout, temb_channels=512):
- super().__init__()
- self.in_channels = in_channels
- out_channels = in_channels if out_channels is None else out_channels
- self.out_channels = out_channels
- self.use_conv_shortcut = conv_shortcut
-
- self.norm1 = Normalize(in_channels)
- self.conv1 = torch.nn.Conv2d(in_channels,
- out_channels,
- kernel_size=3,
- stride=1,
- padding=1)
- if temb_channels > 0:
- self.temb_proj = torch.nn.Linear(temb_channels,
- out_channels)
- self.norm2 = Normalize(out_channels)
- self.dropout = torch.nn.Dropout(dropout)
- self.conv2 = torch.nn.Conv2d(out_channels,
- out_channels,
- kernel_size=3,
- stride=1,
- padding=1)
- if self.in_channels != self.out_channels:
- if self.use_conv_shortcut:
- self.conv_shortcut = torch.nn.Conv2d(in_channels,
- out_channels,
- kernel_size=3,
- stride=1,
- padding=1)
- else:
- self.nin_shortcut = torch.nn.Conv2d(in_channels,
- out_channels,
- kernel_size=1,
- stride=1,
- padding=0)
-
- def forward(self, x, temb):
- h = x
- h = self.norm1(h)
- h = nonlinearity(h)
- h = self.conv1(h)
-
- if temb is not None:
- h = h + self.temb_proj(nonlinearity(temb))[:,:,None,None]
-
- h = self.norm2(h)
- h = nonlinearity(h)
- h = self.dropout(h)
- h = self.conv2(h)
-
- if self.in_channels != self.out_channels:
- if self.use_conv_shortcut:
- x = self.conv_shortcut(x)
- else:
- x = self.nin_shortcut(x)
-
- return x+h
-
-
-class LinAttnBlock(LinearAttention):
- """to match AttnBlock usage"""
- def __init__(self, in_channels):
- super().__init__(dim=in_channels, heads=1, dim_head=in_channels)
-
-
-class AttnBlock(nn.Module):
- def __init__(self, in_channels):
- super().__init__()
- self.in_channels = in_channels
-
- self.norm = Normalize(in_channels)
- self.q = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=1,
- stride=1,
- padding=0)
- self.k = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=1,
- stride=1,
- padding=0)
- self.v = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=1,
- stride=1,
- padding=0)
- self.proj_out = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=1,
- stride=1,
- padding=0)
-
-
- def forward(self, x):
- h_ = x
- h_ = self.norm(h_)
- q = self.q(h_)
- k = self.k(h_)
- v = self.v(h_)
-
- # compute attention
- b,c,h,w = q.shape
- q = q.reshape(b,c,h*w)
- q = q.permute(0,2,1) # b,hw,c
- k = k.reshape(b,c,h*w) # b,c,hw
- w_ = torch.bmm(q,k) # b,hw,hw w[b,i,j]=sum_c q[b,i,c]k[b,c,j]
- w_ = w_ * (int(c)**(-0.5))
- w_ = torch.nn.functional.softmax(w_, dim=2)
-
- # attend to values
- v = v.reshape(b,c,h*w)
- w_ = w_.permute(0,2,1) # b,hw,hw (first hw of k, second of q)
- h_ = torch.bmm(v,w_) # b, c,hw (hw of q) h_[b,c,j] = sum_i v[b,c,i] w_[b,i,j]
- h_ = h_.reshape(b,c,h,w)
-
- h_ = self.proj_out(h_)
-
- return x+h_
-
-
-def make_attn(in_channels, attn_type="vanilla"):
- assert attn_type in ["vanilla", "linear", "none"], f'attn_type {attn_type} unknown'
- print(f"making attention of type '{attn_type}' with {in_channels} in_channels")
- if attn_type == "vanilla":
- return AttnBlock(in_channels)
- elif attn_type == "none":
- return nn.Identity(in_channels)
- else:
- return LinAttnBlock(in_channels)
-
-
-class Model(nn.Module):
- def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
- attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
- resolution, use_timestep=True, use_linear_attn=False, attn_type="vanilla"):
- super().__init__()
- if use_linear_attn: attn_type = "linear"
- self.ch = ch
- self.temb_ch = self.ch*4
- self.num_resolutions = len(ch_mult)
- self.num_res_blocks = num_res_blocks
- self.resolution = resolution
- self.in_channels = in_channels
-
- self.use_timestep = use_timestep
- if self.use_timestep:
- # timestep embedding
- self.temb = nn.Module()
- self.temb.dense = nn.ModuleList([
- torch.nn.Linear(self.ch,
- self.temb_ch),
- torch.nn.Linear(self.temb_ch,
- self.temb_ch),
- ])
-
- # downsampling
- self.conv_in = torch.nn.Conv2d(in_channels,
- self.ch,
- kernel_size=3,
- stride=1,
- padding=1)
-
- curr_res = resolution
- in_ch_mult = (1,)+tuple(ch_mult)
- self.down = nn.ModuleList()
- for i_level in range(self.num_resolutions):
- block = nn.ModuleList()
- attn = nn.ModuleList()
- block_in = ch*in_ch_mult[i_level]
- block_out = ch*ch_mult[i_level]
- for i_block in range(self.num_res_blocks):
- block.append(ResnetBlock(in_channels=block_in,
- out_channels=block_out,
- temb_channels=self.temb_ch,
- dropout=dropout))
- block_in = block_out
- if curr_res in attn_resolutions:
- attn.append(make_attn(block_in, attn_type=attn_type))
- down = nn.Module()
- down.block = block
- down.attn = attn
- if i_level != self.num_resolutions-1:
- down.downsample = Downsample(block_in, resamp_with_conv)
- curr_res = curr_res // 2
- self.down.append(down)
-
- # middle
- self.mid = nn.Module()
- self.mid.block_1 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
- self.mid.attn_1 = make_attn(block_in, attn_type=attn_type)
- self.mid.block_2 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
-
- # upsampling
- self.up = nn.ModuleList()
- for i_level in reversed(range(self.num_resolutions)):
- block = nn.ModuleList()
- attn = nn.ModuleList()
- block_out = ch*ch_mult[i_level]
- skip_in = ch*ch_mult[i_level]
- for i_block in range(self.num_res_blocks+1):
- if i_block == self.num_res_blocks:
- skip_in = ch*in_ch_mult[i_level]
- block.append(ResnetBlock(in_channels=block_in+skip_in,
- out_channels=block_out,
- temb_channels=self.temb_ch,
- dropout=dropout))
- block_in = block_out
- if curr_res in attn_resolutions:
- attn.append(make_attn(block_in, attn_type=attn_type))
- up = nn.Module()
- up.block = block
- up.attn = attn
- if i_level != 0:
- up.upsample = Upsample(block_in, resamp_with_conv)
- curr_res = curr_res * 2
- self.up.insert(0, up) # prepend to get consistent order
-
- # end
- self.norm_out = Normalize(block_in)
- self.conv_out = torch.nn.Conv2d(block_in,
- out_ch,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, x, t=None, context=None):
- #assert x.shape[2] == x.shape[3] == self.resolution
- if context is not None:
- # assume aligned context, cat along channel axis
- x = torch.cat((x, context), dim=1)
- if self.use_timestep:
- # timestep embedding
- assert t is not None
- temb = get_timestep_embedding(t, self.ch)
- temb = self.temb.dense[0](temb)
- temb = nonlinearity(temb)
- temb = self.temb.dense[1](temb)
- else:
- temb = None
-
- # downsampling
- hs = [self.conv_in(x)]
- for i_level in range(self.num_resolutions):
- for i_block in range(self.num_res_blocks):
- h = self.down[i_level].block[i_block](hs[-1], temb)
- if len(self.down[i_level].attn) > 0:
- h = self.down[i_level].attn[i_block](h)
- hs.append(h)
- if i_level != self.num_resolutions-1:
- hs.append(self.down[i_level].downsample(hs[-1]))
-
- # middle
- h = hs[-1]
- h = self.mid.block_1(h, temb)
- h = self.mid.attn_1(h)
- h = self.mid.block_2(h, temb)
-
- # upsampling
- for i_level in reversed(range(self.num_resolutions)):
- for i_block in range(self.num_res_blocks+1):
- h = self.up[i_level].block[i_block](
- torch.cat([h, hs.pop()], dim=1), temb)
- if len(self.up[i_level].attn) > 0:
- h = self.up[i_level].attn[i_block](h)
- if i_level != 0:
- h = self.up[i_level].upsample(h)
-
- # end
- h = self.norm_out(h)
- h = nonlinearity(h)
- h = self.conv_out(h)
- return h
-
- def get_last_layer(self):
- return self.conv_out.weight
-
-
-class Encoder(nn.Module):
- def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
- attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
- resolution, z_channels, double_z=True, use_linear_attn=False, attn_type="vanilla",
- **ignore_kwargs):
- super().__init__()
- if use_linear_attn: attn_type = "linear"
- self.ch = ch
- self.temb_ch = 0
- self.num_resolutions = len(ch_mult)
- self.num_res_blocks = num_res_blocks
- self.resolution = resolution
- self.in_channels = in_channels
-
- # downsampling
- self.conv_in = torch.nn.Conv2d(in_channels,
- self.ch,
- kernel_size=3,
- stride=1,
- padding=1)
-
- curr_res = resolution
- in_ch_mult = (1,)+tuple(ch_mult)
- self.in_ch_mult = in_ch_mult
- self.down = nn.ModuleList()
- for i_level in range(self.num_resolutions):
- block = nn.ModuleList()
- attn = nn.ModuleList()
- block_in = ch*in_ch_mult[i_level]
- block_out = ch*ch_mult[i_level]
- for i_block in range(self.num_res_blocks):
- block.append(ResnetBlock(in_channels=block_in,
- out_channels=block_out,
- temb_channels=self.temb_ch,
- dropout=dropout))
- block_in = block_out
- if curr_res in attn_resolutions:
- attn.append(make_attn(block_in, attn_type=attn_type))
- down = nn.Module()
- down.block = block
- down.attn = attn
- if i_level != self.num_resolutions-1:
- down.downsample = Downsample(block_in, resamp_with_conv)
- curr_res = curr_res // 2
- self.down.append(down)
-
- # middle
- self.mid = nn.Module()
- self.mid.block_1 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
- self.mid.attn_1 = make_attn(block_in, attn_type=attn_type)
- self.mid.block_2 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
-
- # end
- self.norm_out = Normalize(block_in)
- self.conv_out = torch.nn.Conv2d(block_in,
- 2*z_channels if double_z else z_channels,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, x):
- # timestep embedding
- temb = None
-
- # downsampling
- hs = [self.conv_in(x)]
- for i_level in range(self.num_resolutions):
- for i_block in range(self.num_res_blocks):
- h = self.down[i_level].block[i_block](hs[-1], temb)
- if len(self.down[i_level].attn) > 0:
- h = self.down[i_level].attn[i_block](h)
- hs.append(h)
- if i_level != self.num_resolutions-1:
- hs.append(self.down[i_level].downsample(hs[-1]))
-
- # middle
- h = hs[-1]
- h = self.mid.block_1(h, temb)
- h = self.mid.attn_1(h)
- h = self.mid.block_2(h, temb)
-
- # end
- h = self.norm_out(h)
- h = nonlinearity(h)
- h = self.conv_out(h)
- return h
-
-
-class Decoder(nn.Module):
- def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks,
- attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels,
- resolution, z_channels, give_pre_end=False, tanh_out=False, use_linear_attn=False,
- attn_type="vanilla", **ignorekwargs):
- super().__init__()
- if use_linear_attn: attn_type = "linear"
- self.ch = ch
- self.temb_ch = 0
- self.num_resolutions = len(ch_mult)
- self.num_res_blocks = num_res_blocks
- self.resolution = resolution
- self.in_channels = in_channels
- self.give_pre_end = give_pre_end
- self.tanh_out = tanh_out
-
- # compute in_ch_mult, block_in and curr_res at lowest res
- in_ch_mult = (1,)+tuple(ch_mult)
- block_in = ch*ch_mult[self.num_resolutions-1]
- curr_res = resolution // 2**(self.num_resolutions-1)
- self.z_shape = (1,z_channels,curr_res,curr_res)
- print("Working with z of shape {} = {} dimensions.".format(
- self.z_shape, np.prod(self.z_shape)))
-
- # z to block_in
- self.conv_in = torch.nn.Conv2d(z_channels,
- block_in,
- kernel_size=3,
- stride=1,
- padding=1)
-
- # middle
- self.mid = nn.Module()
- self.mid.block_1 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
- self.mid.attn_1 = make_attn(block_in, attn_type=attn_type)
- self.mid.block_2 = ResnetBlock(in_channels=block_in,
- out_channels=block_in,
- temb_channels=self.temb_ch,
- dropout=dropout)
-
- # upsampling
- self.up = nn.ModuleList()
- for i_level in reversed(range(self.num_resolutions)):
- block = nn.ModuleList()
- attn = nn.ModuleList()
- block_out = ch*ch_mult[i_level]
- for i_block in range(self.num_res_blocks+1):
- block.append(ResnetBlock(in_channels=block_in,
- out_channels=block_out,
- temb_channels=self.temb_ch,
- dropout=dropout))
- block_in = block_out
- if curr_res in attn_resolutions:
- attn.append(make_attn(block_in, attn_type=attn_type))
- up = nn.Module()
- up.block = block
- up.attn = attn
- if i_level != 0:
- up.upsample = Upsample(block_in, resamp_with_conv)
- curr_res = curr_res * 2
- self.up.insert(0, up) # prepend to get consistent order
-
- # end
- self.norm_out = Normalize(block_in)
- self.conv_out = torch.nn.Conv2d(block_in,
- out_ch,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, z):
- #assert z.shape[1:] == self.z_shape[1:]
- self.last_z_shape = z.shape
-
- # timestep embedding
- temb = None
-
- # z to block_in
- h = self.conv_in(z)
-
- # middle
- h = self.mid.block_1(h, temb)
- h = self.mid.attn_1(h)
- h = self.mid.block_2(h, temb)
-
- # upsampling
- for i_level in reversed(range(self.num_resolutions)):
- for i_block in range(self.num_res_blocks+1):
- h = self.up[i_level].block[i_block](h, temb)
- if len(self.up[i_level].attn) > 0:
- h = self.up[i_level].attn[i_block](h)
- if i_level != 0:
- h = self.up[i_level].upsample(h)
-
- # end
- if self.give_pre_end:
- return h
-
- h = self.norm_out(h)
- h = nonlinearity(h)
- h = self.conv_out(h)
- if self.tanh_out:
- h = torch.tanh(h)
- return h
-
-
-class SimpleDecoder(nn.Module):
- def __init__(self, in_channels, out_channels, *args, **kwargs):
- super().__init__()
- self.model = nn.ModuleList([nn.Conv2d(in_channels, in_channels, 1),
- ResnetBlock(in_channels=in_channels,
- out_channels=2 * in_channels,
- temb_channels=0, dropout=0.0),
- ResnetBlock(in_channels=2 * in_channels,
- out_channels=4 * in_channels,
- temb_channels=0, dropout=0.0),
- ResnetBlock(in_channels=4 * in_channels,
- out_channels=2 * in_channels,
- temb_channels=0, dropout=0.0),
- nn.Conv2d(2*in_channels, in_channels, 1),
- Upsample(in_channels, with_conv=True)])
- # end
- self.norm_out = Normalize(in_channels)
- self.conv_out = torch.nn.Conv2d(in_channels,
- out_channels,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, x):
- for i, layer in enumerate(self.model):
- if i in [1,2,3]:
- x = layer(x, None)
- else:
- x = layer(x)
-
- h = self.norm_out(x)
- h = nonlinearity(h)
- x = self.conv_out(h)
- return x
-
-
-class UpsampleDecoder(nn.Module):
- def __init__(self, in_channels, out_channels, ch, num_res_blocks, resolution,
- ch_mult=(2,2), dropout=0.0):
- super().__init__()
- # upsampling
- self.temb_ch = 0
- self.num_resolutions = len(ch_mult)
- self.num_res_blocks = num_res_blocks
- block_in = in_channels
- curr_res = resolution // 2 ** (self.num_resolutions - 1)
- self.res_blocks = nn.ModuleList()
- self.upsample_blocks = nn.ModuleList()
- for i_level in range(self.num_resolutions):
- res_block = []
- block_out = ch * ch_mult[i_level]
- for i_block in range(self.num_res_blocks + 1):
- res_block.append(ResnetBlock(in_channels=block_in,
- out_channels=block_out,
- temb_channels=self.temb_ch,
- dropout=dropout))
- block_in = block_out
- self.res_blocks.append(nn.ModuleList(res_block))
- if i_level != self.num_resolutions - 1:
- self.upsample_blocks.append(Upsample(block_in, True))
- curr_res = curr_res * 2
-
- # end
- self.norm_out = Normalize(block_in)
- self.conv_out = torch.nn.Conv2d(block_in,
- out_channels,
- kernel_size=3,
- stride=1,
- padding=1)
-
- def forward(self, x):
- # upsampling
- h = x
- for k, i_level in enumerate(range(self.num_resolutions)):
- for i_block in range(self.num_res_blocks + 1):
- h = self.res_blocks[i_level][i_block](h, None)
- if i_level != self.num_resolutions - 1:
- h = self.upsample_blocks[k](h)
- h = self.norm_out(h)
- h = nonlinearity(h)
- h = self.conv_out(h)
- return h
-
-
-class LatentRescaler(nn.Module):
- def __init__(self, factor, in_channels, mid_channels, out_channels, depth=2):
- super().__init__()
- # residual block, interpolate, residual block
- self.factor = factor
- self.conv_in = nn.Conv2d(in_channels,
- mid_channels,
- kernel_size=3,
- stride=1,
- padding=1)
- self.res_block1 = nn.ModuleList([ResnetBlock(in_channels=mid_channels,
- out_channels=mid_channels,
- temb_channels=0,
- dropout=0.0) for _ in range(depth)])
- self.attn = AttnBlock(mid_channels)
- self.res_block2 = nn.ModuleList([ResnetBlock(in_channels=mid_channels,
- out_channels=mid_channels,
- temb_channels=0,
- dropout=0.0) for _ in range(depth)])
-
- self.conv_out = nn.Conv2d(mid_channels,
- out_channels,
- kernel_size=1,
- )
-
- def forward(self, x):
- x = self.conv_in(x)
- for block in self.res_block1:
- x = block(x, None)
- x = torch.nn.functional.interpolate(x, size=(int(round(x.shape[2]*self.factor)), int(round(x.shape[3]*self.factor))))
- x = self.attn(x)
- for block in self.res_block2:
- x = block(x, None)
- x = self.conv_out(x)
- return x
-
-
-class MergedRescaleEncoder(nn.Module):
- def __init__(self, in_channels, ch, resolution, out_ch, num_res_blocks,
- attn_resolutions, dropout=0.0, resamp_with_conv=True,
- ch_mult=(1,2,4,8), rescale_factor=1.0, rescale_module_depth=1):
- super().__init__()
- intermediate_chn = ch * ch_mult[-1]
- self.encoder = Encoder(in_channels=in_channels, num_res_blocks=num_res_blocks, ch=ch, ch_mult=ch_mult,
- z_channels=intermediate_chn, double_z=False, resolution=resolution,
- attn_resolutions=attn_resolutions, dropout=dropout, resamp_with_conv=resamp_with_conv,
- out_ch=None)
- self.rescaler = LatentRescaler(factor=rescale_factor, in_channels=intermediate_chn,
- mid_channels=intermediate_chn, out_channels=out_ch, depth=rescale_module_depth)
-
- def forward(self, x):
- x = self.encoder(x)
- x = self.rescaler(x)
- return x
-
-
-class MergedRescaleDecoder(nn.Module):
- def __init__(self, z_channels, out_ch, resolution, num_res_blocks, attn_resolutions, ch, ch_mult=(1,2,4,8),
- dropout=0.0, resamp_with_conv=True, rescale_factor=1.0, rescale_module_depth=1):
- super().__init__()
- tmp_chn = z_channels*ch_mult[-1]
- self.decoder = Decoder(out_ch=out_ch, z_channels=tmp_chn, attn_resolutions=attn_resolutions, dropout=dropout,
- resamp_with_conv=resamp_with_conv, in_channels=None, num_res_blocks=num_res_blocks,
- ch_mult=ch_mult, resolution=resolution, ch=ch)
- self.rescaler = LatentRescaler(factor=rescale_factor, in_channels=z_channels, mid_channels=tmp_chn,
- out_channels=tmp_chn, depth=rescale_module_depth)
-
- def forward(self, x):
- x = self.rescaler(x)
- x = self.decoder(x)
- return x
-
-
-class Upsampler(nn.Module):
- def __init__(self, in_size, out_size, in_channels, out_channels, ch_mult=2):
- super().__init__()
- assert out_size >= in_size
- num_blocks = int(np.log2(out_size//in_size))+1
- factor_up = 1.+ (out_size % in_size)
- print(f"Building {self.__class__.__name__} with in_size: {in_size} --> out_size {out_size} and factor {factor_up}")
- self.rescaler = LatentRescaler(factor=factor_up, in_channels=in_channels, mid_channels=2*in_channels,
- out_channels=in_channels)
- self.decoder = Decoder(out_ch=out_channels, resolution=out_size, z_channels=in_channels, num_res_blocks=2,
- attn_resolutions=[], in_channels=None, ch=in_channels,
- ch_mult=[ch_mult for _ in range(num_blocks)])
-
- def forward(self, x):
- x = self.rescaler(x)
- x = self.decoder(x)
- return x
-
-
-class Resize(nn.Module):
- def __init__(self, in_channels=None, learned=False, mode="bilinear"):
- super().__init__()
- self.with_conv = learned
- self.mode = mode
- if self.with_conv:
- print(f"Note: {self.__class__.__name} uses learned downsampling and will ignore the fixed {mode} mode")
- raise NotImplementedError()
- assert in_channels is not None
- # no asymmetric padding in torch conv, must do it ourselves
- self.conv = torch.nn.Conv2d(in_channels,
- in_channels,
- kernel_size=4,
- stride=2,
- padding=1)
-
- def forward(self, x, scale_factor=1.0):
- if scale_factor==1.0:
- return x
- else:
- x = torch.nn.functional.interpolate(x, mode=self.mode, align_corners=False, scale_factor=scale_factor)
- return x
-
-class FirstStagePostProcessor(nn.Module):
-
- def __init__(self, ch_mult:list, in_channels,
- pretrained_model:nn.Module=None,
- reshape=False,
- n_channels=None,
- dropout=0.,
- pretrained_config=None):
- super().__init__()
- if pretrained_config is None:
- assert pretrained_model is not None, 'Either "pretrained_model" or "pretrained_config" must not be None'
- self.pretrained_model = pretrained_model
- else:
- assert pretrained_config is not None, 'Either "pretrained_model" or "pretrained_config" must not be None'
- self.instantiate_pretrained(pretrained_config)
-
- self.do_reshape = reshape
-
- if n_channels is None:
- n_channels = self.pretrained_model.encoder.ch
-
- self.proj_norm = Normalize(in_channels,num_groups=in_channels//2)
- self.proj = nn.Conv2d(in_channels,n_channels,kernel_size=3,
- stride=1,padding=1)
-
- blocks = []
- downs = []
- ch_in = n_channels
- for m in ch_mult:
- blocks.append(ResnetBlock(in_channels=ch_in,out_channels=m*n_channels,dropout=dropout))
- ch_in = m * n_channels
- downs.append(Downsample(ch_in, with_conv=False))
-
- self.model = nn.ModuleList(blocks)
- self.downsampler = nn.ModuleList(downs)
-
-
- def instantiate_pretrained(self, config):
- model = instantiate_from_config(config)
- self.pretrained_model = model.eval()
- # self.pretrained_model.train = False
- for param in self.pretrained_model.parameters():
- param.requires_grad = False
-
-
- @torch.no_grad()
- def encode_with_pretrained(self,x):
- c = self.pretrained_model.encode(x)
- if isinstance(c, DiagonalGaussianDistribution):
- c = c.mode()
- return c
-
- def forward(self,x):
- z_fs = self.encode_with_pretrained(x)
- z = self.proj_norm(z_fs)
- z = self.proj(z)
- z = nonlinearity(z)
-
- for submodel, downmodel in zip(self.model,self.downsampler):
- z = submodel(z,temb=None)
- z = downmodel(z)
-
- if self.do_reshape:
- z = rearrange(z,'b c h w -> b (h w) c')
- return z
-
diff --git a/ldm/modules/diffusionmodules/openaimodel.py b/ldm/modules/diffusionmodules/openaimodel.py
deleted file mode 100644
index fcf95d1e..00000000
--- a/ldm/modules/diffusionmodules/openaimodel.py
+++ /dev/null
@@ -1,961 +0,0 @@
-from abc import abstractmethod
-from functools import partial
-import math
-from typing import Iterable
-
-import numpy as np
-import torch as th
-import torch.nn as nn
-import torch.nn.functional as F
-
-from ldm.modules.diffusionmodules.util import (
- checkpoint,
- conv_nd,
- linear,
- avg_pool_nd,
- zero_module,
- normalization,
- timestep_embedding,
-)
-from ldm.modules.attention import SpatialTransformer
-
-
-# dummy replace
-def convert_module_to_f16(x):
- pass
-
-def convert_module_to_f32(x):
- pass
-
-
-## go
-class AttentionPool2d(nn.Module):
- """
- Adapted from CLIP: https://github.com/openai/CLIP/blob/main/clip/model.py
- """
-
- def __init__(
- self,
- spacial_dim: int,
- embed_dim: int,
- num_heads_channels: int,
- output_dim: int = None,
- ):
- super().__init__()
- self.positional_embedding = nn.Parameter(th.randn(embed_dim, spacial_dim ** 2 + 1) / embed_dim ** 0.5)
- self.qkv_proj = conv_nd(1, embed_dim, 3 * embed_dim, 1)
- self.c_proj = conv_nd(1, embed_dim, output_dim or embed_dim, 1)
- self.num_heads = embed_dim // num_heads_channels
- self.attention = QKVAttention(self.num_heads)
-
- def forward(self, x):
- b, c, *_spatial = x.shape
- x = x.reshape(b, c, -1) # NC(HW)
- x = th.cat([x.mean(dim=-1, keepdim=True), x], dim=-1) # NC(HW+1)
- x = x + self.positional_embedding[None, :, :].to(x.dtype) # NC(HW+1)
- x = self.qkv_proj(x)
- x = self.attention(x)
- x = self.c_proj(x)
- return x[:, :, 0]
-
-
-class TimestepBlock(nn.Module):
- """
- Any module where forward() takes timestep embeddings as a second argument.
- """
-
- @abstractmethod
- def forward(self, x, emb):
- """
- Apply the module to `x` given `emb` timestep embeddings.
- """
-
-
-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, x, emb, context=None):
- for layer in self:
- if isinstance(layer, TimestepBlock):
- x = layer(x, emb)
- elif isinstance(layer, SpatialTransformer):
- x = layer(x, context)
- else:
- x = layer(x)
- return x
-
-
-class Upsample(nn.Module):
- """
- An upsampling layer with an optional convolution.
- :param channels: channels in the inputs and outputs.
- :param use_conv: a bool determining if a convolution is applied.
- :param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
- upsampling occurs in the inner-two dimensions.
- """
-
- def __init__(self, channels, use_conv, dims=2, out_channels=None, padding=1):
- super().__init__()
- self.channels = channels
- self.out_channels = out_channels or channels
- self.use_conv = use_conv
- self.dims = dims
- if use_conv:
- self.conv = conv_nd(dims, self.channels, self.out_channels, 3, padding=padding)
-
- def forward(self, x):
- assert x.shape[1] == self.channels
- if self.dims == 3:
- x = F.interpolate(
- x, (x.shape[2], x.shape[3] * 2, x.shape[4] * 2), mode="nearest"
- )
- else:
- x = F.interpolate(x, scale_factor=2, mode="nearest")
- if self.use_conv:
- x = self.conv(x)
- return x
-
-class TransposedUpsample(nn.Module):
- 'Learned 2x upsampling without padding'
- def __init__(self, channels, out_channels=None, ks=5):
- super().__init__()
- self.channels = channels
- self.out_channels = out_channels or channels
-
- self.up = nn.ConvTranspose2d(self.channels,self.out_channels,kernel_size=ks,stride=2)
-
- def forward(self,x):
- return self.up(x)
-
-
-class Downsample(nn.Module):
- """
- A downsampling layer with an optional convolution.
- :param channels: channels in the inputs and outputs.
- :param use_conv: a bool determining if a convolution is applied.
- :param dims: determines if the signal is 1D, 2D, or 3D. If 3D, then
- downsampling occurs in the inner-two dimensions.
- """
-
- def __init__(self, channels, use_conv, dims=2, out_channels=None,padding=1):
- super().__init__()
- self.channels = channels
- self.out_channels = out_channels or channels
- self.use_conv = use_conv
- self.dims = dims
- stride = 2 if dims != 3 else (1, 2, 2)
- if use_conv:
- self.op = conv_nd(
- dims, self.channels, self.out_channels, 3, stride=stride, padding=padding
- )
- else:
- assert self.channels == self.out_channels
- self.op = avg_pool_nd(dims, kernel_size=stride, stride=stride)
-
- def forward(self, x):
- assert x.shape[1] == self.channels
- return self.op(x)
-
-
-class ResBlock(TimestepBlock):
- """
- A residual block that can optionally change the number of channels.
- :param channels: the number of input channels.
- :param emb_channels: the number of timestep embedding channels.
- :param dropout: the rate of dropout.
- :param out_channels: if specified, the number of out channels.
- :param use_conv: if True and out_channels is specified, use a spatial
- convolution instead of a smaller 1x1 convolution to change the
- channels in the skip connection.
- :param dims: determines if the signal is 1D, 2D, or 3D.
- :param use_checkpoint: if True, use gradient checkpointing on this module.
- :param up: if True, use this block for upsampling.
- :param down: if True, use this block for downsampling.
- """
-
- def __init__(
- self,
- channels,
- emb_channels,
- dropout,
- out_channels=None,
- use_conv=False,
- use_scale_shift_norm=False,
- dims=2,
- use_checkpoint=False,
- up=False,
- down=False,
- ):
- super().__init__()
- self.channels = channels
- self.emb_channels = emb_channels
- self.dropout = dropout
- self.out_channels = out_channels or channels
- self.use_conv = use_conv
- self.use_checkpoint = use_checkpoint
- self.use_scale_shift_norm = use_scale_shift_norm
-
- self.in_layers = nn.Sequential(
- normalization(channels),
- nn.SiLU(),
- conv_nd(dims, channels, self.out_channels, 3, padding=1),
- )
-
- self.updown = up or down
-
- if up:
- self.h_upd = Upsample(channels, False, dims)
- self.x_upd = Upsample(channels, False, dims)
- elif down:
- self.h_upd = Downsample(channels, False, dims)
- self.x_upd = Downsample(channels, False, dims)
- else:
- self.h_upd = self.x_upd = nn.Identity()
-
- self.emb_layers = nn.Sequential(
- nn.SiLU(),
- linear(
- emb_channels,
- 2 * self.out_channels if use_scale_shift_norm else self.out_channels,
- ),
- )
- self.out_layers = nn.Sequential(
- normalization(self.out_channels),
- nn.SiLU(),
- nn.Dropout(p=dropout),
- zero_module(
- conv_nd(dims, self.out_channels, self.out_channels, 3, padding=1)
- ),
- )
-
- if self.out_channels == channels:
- self.skip_connection = nn.Identity()
- elif use_conv:
- self.skip_connection = conv_nd(
- dims, channels, self.out_channels, 3, padding=1
- )
- else:
- self.skip_connection = conv_nd(dims, channels, self.out_channels, 1)
-
- def forward(self, x, emb):
- """
- Apply the block to a Tensor, conditioned on a timestep embedding.
- :param x: an [N x C x ...] Tensor of features.
- :param emb: an [N x emb_channels] Tensor of timestep embeddings.
- :return: an [N x C x ...] Tensor of outputs.
- """
- return checkpoint(
- self._forward, (x, emb), self.parameters(), self.use_checkpoint
- )
-
-
- def _forward(self, x, emb):
- if self.updown:
- in_rest, in_conv = self.in_layers[:-1], self.in_layers[-1]
- h = in_rest(x)
- h = self.h_upd(h)
- x = self.x_upd(x)
- h = in_conv(h)
- else:
- h = self.in_layers(x)
- emb_out = self.emb_layers(emb).type(h.dtype)
- while len(emb_out.shape) < len(h.shape):
- emb_out = emb_out[..., None]
- if self.use_scale_shift_norm:
- out_norm, out_rest = self.out_layers[0], self.out_layers[1:]
- scale, shift = th.chunk(emb_out, 2, dim=1)
- h = out_norm(h) * (1 + scale) + shift
- h = out_rest(h)
- else:
- h = h + emb_out
- h = self.out_layers(h)
- return self.skip_connection(x) + h
-
-
-class AttentionBlock(nn.Module):
- """
- An attention block that allows spatial positions to attend to each other.
- Originally ported from here, but adapted to the N-d case.
- https://github.com/hojonathanho/diffusion/blob/1e0dceb3b3495bbe19116a5e1b3596cd0706c543/diffusion_tf/models/unet.py#L66.
- """
-
- def __init__(
- self,
- channels,
- num_heads=1,
- num_head_channels=-1,
- use_checkpoint=False,
- use_new_attention_order=False,
- ):
- super().__init__()
- self.channels = channels
- if num_head_channels == -1:
- self.num_heads = num_heads
- else:
- assert (
- channels % num_head_channels == 0
- ), f"q,k,v channels {channels} is not divisible by num_head_channels {num_head_channels}"
- self.num_heads = channels // num_head_channels
- self.use_checkpoint = use_checkpoint
- self.norm = normalization(channels)
- self.qkv = conv_nd(1, channels, channels * 3, 1)
- if use_new_attention_order:
- # split qkv before split heads
- self.attention = QKVAttention(self.num_heads)
- else:
- # split heads before split qkv
- self.attention = QKVAttentionLegacy(self.num_heads)
-
- self.proj_out = zero_module(conv_nd(1, channels, channels, 1))
-
- def forward(self, x):
- return checkpoint(self._forward, (x,), self.parameters(), True) # TODO: check checkpoint usage, is True # TODO: fix the .half call!!!
- #return pt_checkpoint(self._forward, x) # pytorch
-
- def _forward(self, x):
- b, c, *spatial = x.shape
- x = x.reshape(b, c, -1)
- qkv = self.qkv(self.norm(x))
- h = self.attention(qkv)
- h = self.proj_out(h)
- return (x + h).reshape(b, c, *spatial)
-
-
-def count_flops_attn(model, _x, y):
- """
- A counter for the `thop` package to count the operations in an
- attention operation.
- Meant to be used like:
- macs, params = thop.profile(
- model,
- inputs=(inputs, timestamps),
- custom_ops={QKVAttention: QKVAttention.count_flops},
- )
- """
- b, c, *spatial = y[0].shape
- num_spatial = int(np.prod(spatial))
- # We perform two matmuls with the same number of ops.
- # The first computes the weight matrix, the second computes
- # the combination of the value vectors.
- matmul_ops = 2 * b * (num_spatial ** 2) * c
- model.total_ops += th.DoubleTensor([matmul_ops])
-
-
-class QKVAttentionLegacy(nn.Module):
- """
- A module which performs QKV attention. Matches legacy QKVAttention + input/ouput heads shaping
- """
-
- def __init__(self, n_heads):
- super().__init__()
- self.n_heads = n_heads
-
- def forward(self, qkv):
- """
- Apply QKV attention.
- :param qkv: an [N x (H * 3 * C) x T] tensor of Qs, Ks, and Vs.
- :return: an [N x (H * C) x T] tensor after attention.
- """
- bs, width, length = qkv.shape
- assert width % (3 * self.n_heads) == 0
- ch = width // (3 * self.n_heads)
- q, k, v = qkv.reshape(bs * self.n_heads, ch * 3, length).split(ch, dim=1)
- scale = 1 / math.sqrt(math.sqrt(ch))
- weight = th.einsum(
- "bct,bcs->bts", q * scale, k * scale
- ) # More stable with f16 than dividing afterwards
- weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
- a = th.einsum("bts,bcs->bct", weight, v)
- return a.reshape(bs, -1, length)
-
- @staticmethod
- def count_flops(model, _x, y):
- return count_flops_attn(model, _x, y)
-
-
-class QKVAttention(nn.Module):
- """
- A module which performs QKV attention and splits in a different order.
- """
-
- def __init__(self, n_heads):
- super().__init__()
- self.n_heads = n_heads
-
- def forward(self, qkv):
- """
- Apply QKV attention.
- :param qkv: an [N x (3 * H * C) x T] tensor of Qs, Ks, and Vs.
- :return: an [N x (H * C) x T] tensor after attention.
- """
- bs, width, length = qkv.shape
- assert width % (3 * self.n_heads) == 0
- ch = width // (3 * self.n_heads)
- q, k, v = qkv.chunk(3, dim=1)
- scale = 1 / math.sqrt(math.sqrt(ch))
- weight = th.einsum(
- "bct,bcs->bts",
- (q * scale).view(bs * self.n_heads, ch, length),
- (k * scale).view(bs * self.n_heads, ch, length),
- ) # More stable with f16 than dividing afterwards
- weight = th.softmax(weight.float(), dim=-1).type(weight.dtype)
- a = th.einsum("bts,bcs->bct", weight, v.reshape(bs * self.n_heads, ch, length))
- return a.reshape(bs, -1, length)
-
- @staticmethod
- def count_flops(model, _x, y):
- return count_flops_attn(model, _x, y)
-
-
-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 attention_resolutions: a collection of downsample rates at which
- attention will take place. May be a set, list, or tuple.
- For example, if this contains 4, then at 4x downsampling, attention
- will be used.
- :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,
- attention_resolutions,
- dropout=0,
- channel_mult=(1, 2, 4, 8),
- conv_resample=True,
- dims=2,
- num_classes=None,
- use_checkpoint=False,
- use_fp16=False,
- 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
- n_embed=None, # custom support for prediction of discrete ids into codebook of first stage vq model
- legacy=True,
- ):
- super().__init__()
- if use_spatial_transformer:
- assert context_dim is not None, 'Fool!! You forgot to include the dimension of your cross-attention conditioning...'
-
- if context_dim is not None:
- assert use_spatial_transformer, 'Fool!! You forgot to use the spatial transformer for your cross-attention conditioning...'
- from omegaconf.listconfig import ListConfig
- if type(context_dim) == ListConfig:
- context_dim = list(context_dim)
-
- 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.image_size = image_size
- self.in_channels = in_channels
- self.model_channels = model_channels
- self.out_channels = out_channels
- self.num_res_blocks = num_res_blocks
- self.attention_resolutions = attention_resolutions
- 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 = th.float16 if use_fp16 else th.float32
- self.num_heads = num_heads
- self.num_head_channels = num_head_channels
- self.num_heads_upsample = num_heads_upsample
- self.predict_codebook_ids = n_embed is not None
-
- time_embed_dim = model_channels * 4
- self.time_embed = nn.Sequential(
- linear(model_channels, time_embed_dim),
- nn.SiLU(),
- linear(time_embed_dim, time_embed_dim),
- )
-
- if self.num_classes is not None:
- self.label_emb = nn.Embedding(num_classes, time_embed_dim)
-
- self.input_blocks = nn.ModuleList(
- [
- TimestepEmbedSequential(
- conv_nd(dims, in_channels, model_channels, 3, padding=1)
- )
- ]
- )
- self._feature_size = model_channels
- input_block_chans = [model_channels]
- ch = model_channels
- ds = 1
- for level, mult in enumerate(channel_mult):
- for _ in range(num_res_blocks):
- layers = [
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- out_channels=mult * model_channels,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- )
- ]
- ch = mult * model_channels
- if ds in attention_resolutions:
- 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
- layers.append(
- AttentionBlock(
- ch,
- use_checkpoint=use_checkpoint,
- num_heads=num_heads,
- num_head_channels=dim_head,
- use_new_attention_order=use_new_attention_order,
- ) if not use_spatial_transformer else SpatialTransformer(
- ch, num_heads, dim_head, depth=transformer_depth, context_dim=context_dim
- )
- )
- 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(
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- out_channels=out_ch,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- down=True,
- )
- if resblock_updown
- else Downsample(
- ch, conv_resample, dims=dims, out_channels=out_ch
- )
- )
- )
- 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
- self.middle_block = TimestepEmbedSequential(
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- ),
- AttentionBlock(
- ch,
- use_checkpoint=use_checkpoint,
- num_heads=num_heads,
- num_head_channels=dim_head,
- use_new_attention_order=use_new_attention_order,
- ) if not use_spatial_transformer else SpatialTransformer(
- ch, num_heads, dim_head, depth=transformer_depth, context_dim=context_dim
- ),
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- ),
- )
- self._feature_size += ch
-
- self.output_blocks = nn.ModuleList([])
- for level, mult in list(enumerate(channel_mult))[::-1]:
- for i in range(num_res_blocks + 1):
- ich = input_block_chans.pop()
- layers = [
- ResBlock(
- ch + ich,
- time_embed_dim,
- dropout,
- out_channels=model_channels * mult,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- )
- ]
- ch = model_channels * mult
- if ds in attention_resolutions:
- 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
- layers.append(
- AttentionBlock(
- ch,
- use_checkpoint=use_checkpoint,
- num_heads=num_heads_upsample,
- num_head_channels=dim_head,
- use_new_attention_order=use_new_attention_order,
- ) if not use_spatial_transformer else SpatialTransformer(
- ch, num_heads, dim_head, depth=transformer_depth, context_dim=context_dim
- )
- )
- if level and i == num_res_blocks:
- out_ch = ch
- layers.append(
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- out_channels=out_ch,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- up=True,
- )
- if resblock_updown
- else Upsample(ch, conv_resample, dims=dims, out_channels=out_ch)
- )
- ds //= 2
- self.output_blocks.append(TimestepEmbedSequential(*layers))
- self._feature_size += ch
-
- self.out = nn.Sequential(
- normalization(ch),
- nn.SiLU(),
- zero_module(conv_nd(dims, model_channels, out_channels, 3, padding=1)),
- )
- if self.predict_codebook_ids:
- self.id_predictor = nn.Sequential(
- normalization(ch),
- conv_nd(dims, model_channels, n_embed, 1),
- #nn.LogSoftmax(dim=1) # change to cross_entropy and produce non-normalized logits
- )
-
- def convert_to_fp16(self):
- """
- Convert the torso of the model to float16.
- """
- self.input_blocks.apply(convert_module_to_f16)
- self.middle_block.apply(convert_module_to_f16)
- self.output_blocks.apply(convert_module_to_f16)
-
- def convert_to_fp32(self):
- """
- Convert the torso of the model to float32.
- """
- self.input_blocks.apply(convert_module_to_f32)
- self.middle_block.apply(convert_module_to_f32)
- self.output_blocks.apply(convert_module_to_f32)
-
- def forward(self, x, timesteps=None, context=None, y=None,**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.
- """
- 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)
- emb = self.time_embed(t_emb)
-
- if self.num_classes is not None:
- assert y.shape == (x.shape[0],)
- emb = emb + self.label_emb(y)
-
- h = x.type(self.dtype)
- for module in self.input_blocks:
- h = module(h, emb, context)
- hs.append(h)
- h = self.middle_block(h, emb, context)
- for module in self.output_blocks:
- h = th.cat([h, hs.pop()], dim=1)
- h = module(h, emb, context)
- h = h.type(x.dtype)
- if self.predict_codebook_ids:
- return self.id_predictor(h)
- else:
- return self.out(h)
-
-
-class EncoderUNetModel(nn.Module):
- """
- The half UNet model with attention and timestep embedding.
- For usage, see UNet.
- """
-
- def __init__(
- self,
- image_size,
- in_channels,
- model_channels,
- out_channels,
- num_res_blocks,
- attention_resolutions,
- dropout=0,
- channel_mult=(1, 2, 4, 8),
- conv_resample=True,
- dims=2,
- use_checkpoint=False,
- use_fp16=False,
- num_heads=1,
- num_head_channels=-1,
- num_heads_upsample=-1,
- use_scale_shift_norm=False,
- resblock_updown=False,
- use_new_attention_order=False,
- pool="adaptive",
- *args,
- **kwargs
- ):
- super().__init__()
-
- if num_heads_upsample == -1:
- num_heads_upsample = num_heads
-
- self.in_channels = in_channels
- self.model_channels = model_channels
- self.out_channels = out_channels
- self.num_res_blocks = num_res_blocks
- self.attention_resolutions = attention_resolutions
- self.dropout = dropout
- self.channel_mult = channel_mult
- self.conv_resample = conv_resample
- self.use_checkpoint = use_checkpoint
- self.dtype = th.float16 if use_fp16 else th.float32
- self.num_heads = num_heads
- self.num_head_channels = num_head_channels
- self.num_heads_upsample = num_heads_upsample
-
- time_embed_dim = model_channels * 4
- self.time_embed = nn.Sequential(
- linear(model_channels, time_embed_dim),
- nn.SiLU(),
- linear(time_embed_dim, time_embed_dim),
- )
-
- self.input_blocks = nn.ModuleList(
- [
- TimestepEmbedSequential(
- conv_nd(dims, in_channels, model_channels, 3, padding=1)
- )
- ]
- )
- self._feature_size = model_channels
- input_block_chans = [model_channels]
- ch = model_channels
- ds = 1
- for level, mult in enumerate(channel_mult):
- for _ in range(num_res_blocks):
- layers = [
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- out_channels=mult * model_channels,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- )
- ]
- ch = mult * model_channels
- if ds in attention_resolutions:
- layers.append(
- AttentionBlock(
- ch,
- use_checkpoint=use_checkpoint,
- num_heads=num_heads,
- num_head_channels=num_head_channels,
- use_new_attention_order=use_new_attention_order,
- )
- )
- 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(
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- out_channels=out_ch,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- down=True,
- )
- if resblock_updown
- else Downsample(
- ch, conv_resample, dims=dims, out_channels=out_ch
- )
- )
- )
- ch = out_ch
- input_block_chans.append(ch)
- ds *= 2
- self._feature_size += ch
-
- self.middle_block = TimestepEmbedSequential(
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- ),
- AttentionBlock(
- ch,
- use_checkpoint=use_checkpoint,
- num_heads=num_heads,
- num_head_channels=num_head_channels,
- use_new_attention_order=use_new_attention_order,
- ),
- ResBlock(
- ch,
- time_embed_dim,
- dropout,
- dims=dims,
- use_checkpoint=use_checkpoint,
- use_scale_shift_norm=use_scale_shift_norm,
- ),
- )
- self._feature_size += ch
- self.pool = pool
- if pool == "adaptive":
- self.out = nn.Sequential(
- normalization(ch),
- nn.SiLU(),
- nn.AdaptiveAvgPool2d((1, 1)),
- zero_module(conv_nd(dims, ch, out_channels, 1)),
- nn.Flatten(),
- )
- elif pool == "attention":
- assert num_head_channels != -1
- self.out = nn.Sequential(
- normalization(ch),
- nn.SiLU(),
- AttentionPool2d(
- (image_size // ds), ch, num_head_channels, out_channels
- ),
- )
- elif pool == "spatial":
- self.out = nn.Sequential(
- nn.Linear(self._feature_size, 2048),
- nn.ReLU(),
- nn.Linear(2048, self.out_channels),
- )
- elif pool == "spatial_v2":
- self.out = nn.Sequential(
- nn.Linear(self._feature_size, 2048),
- normalization(2048),
- nn.SiLU(),
- nn.Linear(2048, self.out_channels),
- )
- else:
- raise NotImplementedError(f"Unexpected {pool} pooling")
-
- def convert_to_fp16(self):
- """
- Convert the torso of the model to float16.
- """
- self.input_blocks.apply(convert_module_to_f16)
- self.middle_block.apply(convert_module_to_f16)
-
- def convert_to_fp32(self):
- """
- Convert the torso of the model to float32.
- """
- self.input_blocks.apply(convert_module_to_f32)
- self.middle_block.apply(convert_module_to_f32)
-
- def forward(self, x, timesteps):
- """
- 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.
- :return: an [N x K] Tensor of outputs.
- """
- emb = self.time_embed(timestep_embedding(timesteps, self.model_channels))
-
- results = []
- h = x.type(self.dtype)
- for module in self.input_blocks:
- h = module(h, emb)
- if self.pool.startswith("spatial"):
- results.append(h.type(x.dtype).mean(dim=(2, 3)))
- h = self.middle_block(h, emb)
- if self.pool.startswith("spatial"):
- results.append(h.type(x.dtype).mean(dim=(2, 3)))
- h = th.cat(results, axis=-1)
- return self.out(h)
- else:
- h = h.type(x.dtype)
- return self.out(h)
-
diff --git a/ldm/modules/diffusionmodules/util.py b/ldm/modules/diffusionmodules/util.py
deleted file mode 100644
index a952e6c4..00000000
--- a/ldm/modules/diffusionmodules/util.py
+++ /dev/null
@@ -1,267 +0,0 @@
-# adopted from
-# https://github.com/openai/improved-diffusion/blob/main/improved_diffusion/gaussian_diffusion.py
-# and
-# https://github.com/lucidrains/denoising-diffusion-pytorch/blob/7706bdfc6f527f58d33f84b7b522e61e6e3164b3/denoising_diffusion_pytorch/denoising_diffusion_pytorch.py
-# and
-# https://github.com/openai/guided-diffusion/blob/0ba878e517b276c45d1195eb29f6f5f72659a05b/guided_diffusion/nn.py
-#
-# thanks!
-
-
-import os
-import math
-import torch
-import torch.nn as nn
-import numpy as np
-from einops import repeat
-
-from ldm.util import instantiate_from_config
-
-
-def make_beta_schedule(schedule, n_timestep, linear_start=1e-4, linear_end=2e-2, cosine_s=8e-3):
- if schedule == "linear":
- betas = (
- torch.linspace(linear_start ** 0.5, linear_end ** 0.5, n_timestep, dtype=torch.float64) ** 2
- )
-
- elif schedule == "cosine":
- timesteps = (
- torch.arange(n_timestep + 1, dtype=torch.float64) / n_timestep + cosine_s
- )
- alphas = timesteps / (1 + cosine_s) * np.pi / 2
- alphas = torch.cos(alphas).pow(2)
- alphas = alphas / alphas[0]
- betas = 1 - alphas[1:] / alphas[:-1]
- betas = np.clip(betas, a_min=0, a_max=0.999)
-
- elif schedule == "sqrt_linear":
- betas = torch.linspace(linear_start, linear_end, n_timestep, dtype=torch.float64)
- elif schedule == "sqrt":
- betas = torch.linspace(linear_start, linear_end, n_timestep, dtype=torch.float64) ** 0.5
- else:
- raise ValueError(f"schedule '{schedule}' unknown.")
- return betas.numpy()
-
-
-def make_ddim_timesteps(ddim_discr_method, num_ddim_timesteps, num_ddpm_timesteps, verbose=True):
- if ddim_discr_method == 'uniform':
- c = num_ddpm_timesteps // num_ddim_timesteps
- ddim_timesteps = np.asarray(list(range(0, num_ddpm_timesteps, c)))
- elif ddim_discr_method == 'quad':
- ddim_timesteps = ((np.linspace(0, np.sqrt(num_ddpm_timesteps * .8), num_ddim_timesteps)) ** 2).astype(int)
- else:
- raise NotImplementedError(f'There is no ddim discretization method called "{ddim_discr_method}"')
-
- # assert ddim_timesteps.shape[0] == num_ddim_timesteps
- # add one to get the final alpha values right (the ones from first scale to data during sampling)
- steps_out = ddim_timesteps + 1
- if verbose:
- print(f'Selected timesteps for ddim sampler: {steps_out}')
- return steps_out
-
-
-def make_ddim_sampling_parameters(alphacums, ddim_timesteps, eta, verbose=True):
- # select alphas for computing the variance schedule
- alphas = alphacums[ddim_timesteps]
- alphas_prev = np.asarray([alphacums[0]] + alphacums[ddim_timesteps[:-1]].tolist())
-
- # according the the formula provided in https://arxiv.org/abs/2010.02502
- sigmas = eta * np.sqrt((1 - alphas_prev) / (1 - alphas) * (1 - alphas / alphas_prev))
- if verbose:
- print(f'Selected alphas for ddim sampler: a_t: {alphas}; a_(t-1): {alphas_prev}')
- print(f'For the chosen value of eta, which is {eta}, '
- f'this results in the following sigma_t schedule for ddim sampler {sigmas}')
- return sigmas, alphas, alphas_prev
-
-
-def betas_for_alpha_bar(num_diffusion_timesteps, alpha_bar, max_beta=0.999):
- """
- Create a beta schedule that discretizes the given alpha_t_bar function,
- which defines the cumulative product of (1-beta) over time from t = [0,1].
- :param num_diffusion_timesteps: the number of betas to produce.
- :param alpha_bar: a lambda that takes an argument t from 0 to 1 and
- produces the cumulative product of (1-beta) up to that
- part of the diffusion process.
- :param max_beta: the maximum beta to use; use values lower than 1 to
- prevent singularities.
- """
- betas = []
- for i in range(num_diffusion_timesteps):
- t1 = i / num_diffusion_timesteps
- t2 = (i + 1) / num_diffusion_timesteps
- betas.append(min(1 - alpha_bar(t2) / alpha_bar(t1), max_beta))
- return np.array(betas)
-
-
-def extract_into_tensor(a, t, x_shape):
- b, *_ = t.shape
- out = a.gather(-1, t)
- return out.reshape(b, *((1,) * (len(x_shape) - 1)))
-
-
-def checkpoint(func, inputs, params, flag):
- """
- Evaluate a function without caching intermediate activations, allowing for
- reduced memory at the expense of extra compute in the backward pass.
- :param func: the function to evaluate.
- :param inputs: the argument sequence to pass to `func`.
- :param params: a sequence of parameters `func` depends on but does not
- explicitly take as arguments.
- :param flag: if False, disable gradient checkpointing.
- """
- if flag:
- args = tuple(inputs) + tuple(params)
- return CheckpointFunction.apply(func, len(inputs), *args)
- else:
- return func(*inputs)
-
-
-class CheckpointFunction(torch.autograd.Function):
- @staticmethod
- def forward(ctx, run_function, length, *args):
- ctx.run_function = run_function
- ctx.input_tensors = list(args[:length])
- ctx.input_params = list(args[length:])
-
- with torch.no_grad():
- output_tensors = ctx.run_function(*ctx.input_tensors)
- return output_tensors
-
- @staticmethod
- def backward(ctx, *output_grads):
- ctx.input_tensors = [x.detach().requires_grad_(True) for x in ctx.input_tensors]
- with torch.enable_grad():
- # Fixes a bug where the first op in run_function modifies the
- # Tensor storage in place, which is not allowed for detach()'d
- # Tensors.
- shallow_copies = [x.view_as(x) for x in ctx.input_tensors]
- output_tensors = ctx.run_function(*shallow_copies)
- input_grads = torch.autograd.grad(
- output_tensors,
- ctx.input_tensors + ctx.input_params,
- output_grads,
- allow_unused=True,
- )
- del ctx.input_tensors
- del ctx.input_params
- del output_tensors
- return (None, None) + input_grads
-
-
-def timestep_embedding(timesteps, dim, max_period=10000, repeat_only=False):
- """
- Create sinusoidal timestep embeddings.
- :param timesteps: a 1-D Tensor of N indices, one per batch element.
- These may be fractional.
- :param dim: the dimension of the output.
- :param max_period: controls the minimum frequency of the embeddings.
- :return: an [N x dim] Tensor of positional embeddings.
- """
- if not repeat_only:
- half = dim // 2
- freqs = torch.exp(
- -math.log(max_period) * torch.arange(start=0, end=half, dtype=torch.float32) / half
- ).to(device=timesteps.device)
- args = timesteps[:, None].float() * freqs[None]
- embedding = torch.cat([torch.cos(args), torch.sin(args)], dim=-1)
- if dim % 2:
- embedding = torch.cat([embedding, torch.zeros_like(embedding[:, :1])], dim=-1)
- else:
- embedding = repeat(timesteps, 'b -> b d', d=dim)
- return embedding
-
-
-def zero_module(module):
- """
- Zero out the parameters of a module and return it.
- """
- for p in module.parameters():
- p.detach().zero_()
- return module
-
-
-def scale_module(module, scale):
- """
- Scale the parameters of a module and return it.
- """
- for p in module.parameters():
- p.detach().mul_(scale)
- return module
-
-
-def mean_flat(tensor):
- """
- Take the mean over all non-batch dimensions.
- """
- return tensor.mean(dim=list(range(1, len(tensor.shape))))
-
-
-def normalization(channels):
- """
- Make a standard normalization layer.
- :param channels: number of input channels.
- :return: an nn.Module for normalization.
- """
- return GroupNorm32(32, channels)
-
-
-# PyTorch 1.7 has SiLU, but we support PyTorch 1.5.
-class SiLU(nn.Module):
- def forward(self, x):
- return x * torch.sigmoid(x)
-
-
-class GroupNorm32(nn.GroupNorm):
- def forward(self, x):
- return super().forward(x.float()).type(x.dtype)
-
-def conv_nd(dims, *args, **kwargs):
- """
- Create a 1D, 2D, or 3D convolution module.
- """
- if dims == 1:
- return nn.Conv1d(*args, **kwargs)
- elif dims == 2:
- return nn.Conv2d(*args, **kwargs)
- elif dims == 3:
- return nn.Conv3d(*args, **kwargs)
- raise ValueError(f"unsupported dimensions: {dims}")
-
-
-def linear(*args, **kwargs):
- """
- Create a linear module.
- """
- return nn.Linear(*args, **kwargs)
-
-
-def avg_pool_nd(dims, *args, **kwargs):
- """
- Create a 1D, 2D, or 3D average pooling module.
- """
- if dims == 1:
- return nn.AvgPool1d(*args, **kwargs)
- elif dims == 2:
- return nn.AvgPool2d(*args, **kwargs)
- elif dims == 3:
- return nn.AvgPool3d(*args, **kwargs)
- raise ValueError(f"unsupported dimensions: {dims}")
-
-
-class HybridConditioner(nn.Module):
-
- def __init__(self, c_concat_config, c_crossattn_config):
- super().__init__()
- self.concat_conditioner = instantiate_from_config(c_concat_config)
- self.crossattn_conditioner = instantiate_from_config(c_crossattn_config)
-
- def forward(self, c_concat, c_crossattn):
- c_concat = self.concat_conditioner(c_concat)
- c_crossattn = self.crossattn_conditioner(c_crossattn)
- return {'c_concat': [c_concat], 'c_crossattn': [c_crossattn]}
-
-
-def noise_like(shape, device, repeat=False):
- repeat_noise = lambda: torch.randn((1, *shape[1:]), device=device).repeat(shape[0], *((1,) * (len(shape) - 1)))
- noise = lambda: torch.randn(shape, device=device)
- return repeat_noise() if repeat else noise() \ No newline at end of file