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738 lines
28 KiB
738 lines
28 KiB
# pytorch_diffusion + derived encoder decoder |
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import math |
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import torch |
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import torch.nn as nn |
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import numpy as np |
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from einops import rearrange |
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from typing import Optional, Any |
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|
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from ..attention import MemoryEfficientCrossAttention |
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from comfy import model_management |
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import comfy.ops |
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|
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if model_management.xformers_enabled_vae(): |
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import xformers |
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import xformers.ops |
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|
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def get_timestep_embedding(timesteps, embedding_dim): |
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""" |
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This matches the implementation in Denoising Diffusion Probabilistic Models: |
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From Fairseq. |
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Build sinusoidal embeddings. |
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This matches the implementation in tensor2tensor, but differs slightly |
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from the description in Section 3.5 of "Attention Is All You Need". |
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""" |
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assert len(timesteps.shape) == 1 |
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|
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half_dim = embedding_dim // 2 |
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emb = math.log(10000) / (half_dim - 1) |
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emb = torch.exp(torch.arange(half_dim, dtype=torch.float32) * -emb) |
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emb = emb.to(device=timesteps.device) |
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emb = timesteps.float()[:, None] * emb[None, :] |
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emb = torch.cat([torch.sin(emb), torch.cos(emb)], dim=1) |
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if embedding_dim % 2 == 1: # zero pad |
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emb = torch.nn.functional.pad(emb, (0,1,0,0)) |
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return emb |
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|
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def nonlinearity(x): |
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# swish |
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return x*torch.sigmoid(x) |
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|
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|
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def Normalize(in_channels, num_groups=32): |
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return torch.nn.GroupNorm(num_groups=num_groups, num_channels=in_channels, eps=1e-6, affine=True) |
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|
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class Upsample(nn.Module): |
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def __init__(self, in_channels, with_conv): |
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super().__init__() |
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self.with_conv = with_conv |
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if self.with_conv: |
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self.conv = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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|
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def forward(self, x): |
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x = torch.nn.functional.interpolate(x, scale_factor=2.0, mode="nearest") |
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if self.with_conv: |
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x = self.conv(x) |
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return x |
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|
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class Downsample(nn.Module): |
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def __init__(self, in_channels, with_conv): |
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super().__init__() |
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self.with_conv = with_conv |
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if self.with_conv: |
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# no asymmetric padding in torch conv, must do it ourselves |
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self.conv = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=3, |
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stride=2, |
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padding=0) |
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|
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def forward(self, x, already_padded=False): |
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if self.with_conv: |
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if not already_padded: |
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pad = (0,1,0,1) |
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x = torch.nn.functional.pad(x, pad, mode="constant", value=0) |
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x = self.conv(x) |
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else: |
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x = torch.nn.functional.avg_pool2d(x, kernel_size=2, stride=2) |
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return x |
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|
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class ResnetBlock(nn.Module): |
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def __init__(self, *, in_channels, out_channels=None, conv_shortcut=False, |
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dropout, temb_channels=512): |
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super().__init__() |
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self.in_channels = in_channels |
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out_channels = in_channels if out_channels is None else out_channels |
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self.out_channels = out_channels |
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self.use_conv_shortcut = conv_shortcut |
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|
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self.swish = torch.nn.SiLU(inplace=True) |
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self.norm1 = Normalize(in_channels) |
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self.conv1 = comfy.ops.Conv2d(in_channels, |
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out_channels, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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if temb_channels > 0: |
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self.temb_proj = comfy.ops.Linear(temb_channels, |
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out_channels) |
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self.norm2 = Normalize(out_channels) |
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self.dropout = torch.nn.Dropout(dropout, inplace=True) |
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self.conv2 = comfy.ops.Conv2d(out_channels, |
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out_channels, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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if self.in_channels != self.out_channels: |
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if self.use_conv_shortcut: |
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self.conv_shortcut = comfy.ops.Conv2d(in_channels, |
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out_channels, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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else: |
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self.nin_shortcut = comfy.ops.Conv2d(in_channels, |
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out_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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|
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def forward(self, x, temb): |
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h = x |
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h = self.norm1(h) |
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h = self.swish(h) |
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h = self.conv1(h) |
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|
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if temb is not None: |
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h = h + self.temb_proj(self.swish(temb))[:,:,None,None] |
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|
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h = self.norm2(h) |
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h = self.swish(h) |
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h = self.dropout(h) |
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h = self.conv2(h) |
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|
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if self.in_channels != self.out_channels: |
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if self.use_conv_shortcut: |
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x = self.conv_shortcut(x) |
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else: |
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x = self.nin_shortcut(x) |
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|
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return x+h |
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|
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def slice_attention(q, k, v): |
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r1 = torch.zeros_like(k, device=q.device) |
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scale = (int(q.shape[-1])**(-0.5)) |
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|
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mem_free_total = model_management.get_free_memory(q.device) |
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|
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gb = 1024 ** 3 |
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tensor_size = q.shape[0] * q.shape[1] * k.shape[2] * q.element_size() |
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modifier = 3 if q.element_size() == 2 else 2.5 |
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mem_required = tensor_size * modifier |
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steps = 1 |
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|
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if mem_required > mem_free_total: |
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steps = 2**(math.ceil(math.log(mem_required / mem_free_total, 2))) |
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|
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while True: |
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try: |
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slice_size = q.shape[1] // steps if (q.shape[1] % steps) == 0 else q.shape[1] |
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for i in range(0, q.shape[1], slice_size): |
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end = i + slice_size |
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s1 = torch.bmm(q[:, i:end], k) * scale |
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|
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s2 = torch.nn.functional.softmax(s1, dim=2).permute(0,2,1) |
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del s1 |
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|
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r1[:, :, i:end] = torch.bmm(v, s2) |
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del s2 |
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break |
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except model_management.OOM_EXCEPTION as e: |
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steps *= 2 |
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if steps > 128: |
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raise e |
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print("out of memory error, increasing steps and trying again", steps) |
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|
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return r1 |
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|
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class AttnBlock(nn.Module): |
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def __init__(self, in_channels): |
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super().__init__() |
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self.in_channels = in_channels |
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|
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self.norm = Normalize(in_channels) |
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self.q = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.k = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.v = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.proj_out = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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|
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def forward(self, x): |
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h_ = x |
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h_ = self.norm(h_) |
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q = self.q(h_) |
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k = self.k(h_) |
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v = self.v(h_) |
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|
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# compute attention |
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b,c,h,w = q.shape |
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|
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q = q.reshape(b,c,h*w) |
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q = q.permute(0,2,1) # b,hw,c |
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k = k.reshape(b,c,h*w) # b,c,hw |
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v = v.reshape(b,c,h*w) |
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|
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r1 = slice_attention(q, k, v) |
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h_ = r1.reshape(b,c,h,w) |
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del r1 |
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h_ = self.proj_out(h_) |
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return x+h_ |
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|
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class MemoryEfficientAttnBlock(nn.Module): |
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""" |
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Uses xformers efficient implementation, |
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see https://github.com/MatthieuTPHR/diffusers/blob/d80b531ff8060ec1ea982b65a1b8df70f73aa67c/src/diffusers/models/attention.py#L223 |
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Note: this is a single-head self-attention operation |
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""" |
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# |
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def __init__(self, in_channels): |
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super().__init__() |
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self.in_channels = in_channels |
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|
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self.norm = Normalize(in_channels) |
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self.q = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.k = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.v = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.proj_out = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.attention_op: Optional[Any] = None |
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|
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def forward(self, x): |
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h_ = x |
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h_ = self.norm(h_) |
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q = self.q(h_) |
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k = self.k(h_) |
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v = self.v(h_) |
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|
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# compute attention |
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B, C, H, W = q.shape |
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q, k, v = map(lambda x: rearrange(x, 'b c h w -> b (h w) c'), (q, k, v)) |
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|
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q, k, v = map( |
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lambda t: t.unsqueeze(3) |
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.reshape(B, t.shape[1], 1, C) |
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.permute(0, 2, 1, 3) |
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.reshape(B * 1, t.shape[1], C) |
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.contiguous(), |
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(q, k, v), |
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) |
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out = xformers.ops.memory_efficient_attention(q, k, v, attn_bias=None, op=self.attention_op) |
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|
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out = ( |
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out.unsqueeze(0) |
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.reshape(B, 1, out.shape[1], C) |
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.permute(0, 2, 1, 3) |
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.reshape(B, out.shape[1], C) |
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) |
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out = rearrange(out, 'b (h w) c -> b c h w', b=B, h=H, w=W, c=C) |
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out = self.proj_out(out) |
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return x+out |
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|
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class MemoryEfficientAttnBlockPytorch(nn.Module): |
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def __init__(self, in_channels): |
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super().__init__() |
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self.in_channels = in_channels |
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|
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self.norm = Normalize(in_channels) |
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self.q = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.k = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.v = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.proj_out = comfy.ops.Conv2d(in_channels, |
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in_channels, |
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kernel_size=1, |
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stride=1, |
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padding=0) |
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self.attention_op: Optional[Any] = None |
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|
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def forward(self, x): |
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h_ = x |
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h_ = self.norm(h_) |
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q = self.q(h_) |
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k = self.k(h_) |
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v = self.v(h_) |
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|
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# compute attention |
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B, C, H, W = q.shape |
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q, k, v = map( |
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lambda t: t.view(B, 1, C, -1).transpose(2, 3).contiguous(), |
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(q, k, v), |
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) |
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|
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try: |
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out = torch.nn.functional.scaled_dot_product_attention(q, k, v, attn_mask=None, dropout_p=0.0, is_causal=False) |
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out = out.transpose(2, 3).reshape(B, C, H, W) |
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except model_management.OOM_EXCEPTION as e: |
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print("scaled_dot_product_attention OOMed: switched to slice attention") |
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out = slice_attention(q.view(B, -1, C), k.view(B, -1, C).transpose(1, 2), v.view(B, -1, C).transpose(1, 2)).reshape(B, C, H, W) |
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|
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out = self.proj_out(out) |
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return x+out |
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|
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class MemoryEfficientCrossAttentionWrapper(MemoryEfficientCrossAttention): |
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def forward(self, x, context=None, mask=None): |
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b, c, h, w = x.shape |
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x = rearrange(x, 'b c h w -> b (h w) c') |
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out = super().forward(x, context=context, mask=mask) |
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out = rearrange(out, 'b (h w) c -> b c h w', h=h, w=w, c=c) |
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return x + out |
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|
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|
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def make_attn(in_channels, attn_type="vanilla", attn_kwargs=None): |
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assert attn_type in ["vanilla", "vanilla-xformers", "memory-efficient-cross-attn", "linear", "none"], f'attn_type {attn_type} unknown' |
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if model_management.xformers_enabled_vae() and attn_type == "vanilla": |
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attn_type = "vanilla-xformers" |
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if model_management.pytorch_attention_enabled() and attn_type == "vanilla": |
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attn_type = "vanilla-pytorch" |
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print(f"making attention of type '{attn_type}' with {in_channels} in_channels") |
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if attn_type == "vanilla": |
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assert attn_kwargs is None |
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return AttnBlock(in_channels) |
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elif attn_type == "vanilla-xformers": |
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print(f"building MemoryEfficientAttnBlock with {in_channels} in_channels...") |
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return MemoryEfficientAttnBlock(in_channels) |
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elif attn_type == "vanilla-pytorch": |
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return MemoryEfficientAttnBlockPytorch(in_channels) |
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elif type == "memory-efficient-cross-attn": |
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attn_kwargs["query_dim"] = in_channels |
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return MemoryEfficientCrossAttentionWrapper(**attn_kwargs) |
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elif attn_type == "none": |
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return nn.Identity(in_channels) |
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else: |
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raise NotImplementedError() |
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|
|
|
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class Model(nn.Module): |
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def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks, |
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attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels, |
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resolution, use_timestep=True, use_linear_attn=False, attn_type="vanilla"): |
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super().__init__() |
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if use_linear_attn: attn_type = "linear" |
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self.ch = ch |
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self.temb_ch = self.ch*4 |
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self.num_resolutions = len(ch_mult) |
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self.num_res_blocks = num_res_blocks |
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self.resolution = resolution |
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self.in_channels = in_channels |
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|
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self.use_timestep = use_timestep |
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if self.use_timestep: |
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# timestep embedding |
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self.temb = nn.Module() |
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self.temb.dense = nn.ModuleList([ |
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comfy.ops.Linear(self.ch, |
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self.temb_ch), |
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comfy.ops.Linear(self.temb_ch, |
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self.temb_ch), |
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]) |
|
|
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# downsampling |
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self.conv_in = comfy.ops.Conv2d(in_channels, |
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self.ch, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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|
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curr_res = resolution |
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in_ch_mult = (1,)+tuple(ch_mult) |
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self.down = nn.ModuleList() |
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for i_level in range(self.num_resolutions): |
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block = nn.ModuleList() |
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attn = nn.ModuleList() |
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block_in = ch*in_ch_mult[i_level] |
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block_out = ch*ch_mult[i_level] |
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for i_block in range(self.num_res_blocks): |
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block.append(ResnetBlock(in_channels=block_in, |
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out_channels=block_out, |
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temb_channels=self.temb_ch, |
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dropout=dropout)) |
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block_in = block_out |
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if curr_res in attn_resolutions: |
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attn.append(make_attn(block_in, attn_type=attn_type)) |
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down = nn.Module() |
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down.block = block |
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down.attn = attn |
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if i_level != self.num_resolutions-1: |
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down.downsample = Downsample(block_in, resamp_with_conv) |
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curr_res = curr_res // 2 |
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self.down.append(down) |
|
|
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# middle |
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self.mid = nn.Module() |
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self.mid.block_1 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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dropout=dropout) |
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self.mid.attn_1 = make_attn(block_in, attn_type=attn_type) |
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self.mid.block_2 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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dropout=dropout) |
|
|
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# upsampling |
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self.up = nn.ModuleList() |
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for i_level in reversed(range(self.num_resolutions)): |
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block = nn.ModuleList() |
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attn = nn.ModuleList() |
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block_out = ch*ch_mult[i_level] |
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skip_in = ch*ch_mult[i_level] |
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for i_block in range(self.num_res_blocks+1): |
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if i_block == self.num_res_blocks: |
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skip_in = ch*in_ch_mult[i_level] |
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block.append(ResnetBlock(in_channels=block_in+skip_in, |
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out_channels=block_out, |
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temb_channels=self.temb_ch, |
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dropout=dropout)) |
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block_in = block_out |
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if curr_res in attn_resolutions: |
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attn.append(make_attn(block_in, attn_type=attn_type)) |
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up = nn.Module() |
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up.block = block |
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up.attn = attn |
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if i_level != 0: |
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up.upsample = Upsample(block_in, resamp_with_conv) |
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curr_res = curr_res * 2 |
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self.up.insert(0, up) # prepend to get consistent order |
|
|
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# end |
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self.norm_out = Normalize(block_in) |
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self.conv_out = comfy.ops.Conv2d(block_in, |
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out_ch, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
|
|
|
def forward(self, x, t=None, context=None): |
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#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) |
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temb = nonlinearity(temb) |
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temb = self.temb.dense[1](temb) |
|
else: |
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temb = None |
|
|
|
# downsampling |
|
hs = [self.conv_in(x)] |
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for i_level in range(self.num_resolutions): |
|
for i_block in range(self.num_res_blocks): |
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h = self.down[i_level].block[i_block](hs[-1], temb) |
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if len(self.down[i_level].attn) > 0: |
|
h = self.down[i_level].attn[i_block](h) |
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hs.append(h) |
|
if i_level != self.num_resolutions-1: |
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hs.append(self.down[i_level].downsample(hs[-1])) |
|
|
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# middle |
|
h = hs[-1] |
|
h = self.mid.block_1(h, temb) |
|
h = self.mid.attn_1(h) |
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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) |
|
|
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# end |
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h = self.norm_out(h) |
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h = nonlinearity(h) |
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h = self.conv_out(h) |
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return h |
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|
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def get_last_layer(self): |
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return self.conv_out.weight |
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|
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class Encoder(nn.Module): |
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def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks, |
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attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels, |
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resolution, z_channels, double_z=True, use_linear_attn=False, attn_type="vanilla", |
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**ignore_kwargs): |
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super().__init__() |
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if use_linear_attn: attn_type = "linear" |
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self.ch = ch |
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self.temb_ch = 0 |
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self.num_resolutions = len(ch_mult) |
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self.num_res_blocks = num_res_blocks |
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self.resolution = resolution |
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self.in_channels = in_channels |
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|
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# downsampling |
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self.conv_in = comfy.ops.Conv2d(in_channels, |
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self.ch, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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|
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curr_res = resolution |
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in_ch_mult = (1,)+tuple(ch_mult) |
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self.in_ch_mult = in_ch_mult |
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self.down = nn.ModuleList() |
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for i_level in range(self.num_resolutions): |
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block = nn.ModuleList() |
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attn = nn.ModuleList() |
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block_in = ch*in_ch_mult[i_level] |
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block_out = ch*ch_mult[i_level] |
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for i_block in range(self.num_res_blocks): |
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block.append(ResnetBlock(in_channels=block_in, |
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out_channels=block_out, |
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temb_channels=self.temb_ch, |
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dropout=dropout)) |
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block_in = block_out |
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if curr_res in attn_resolutions: |
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attn.append(make_attn(block_in, attn_type=attn_type)) |
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down = nn.Module() |
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down.block = block |
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down.attn = attn |
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if i_level != self.num_resolutions-1: |
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down.downsample = Downsample(block_in, resamp_with_conv) |
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curr_res = curr_res // 2 |
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self.down.append(down) |
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|
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# middle |
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self.mid = nn.Module() |
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self.mid.block_1 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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dropout=dropout) |
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self.mid.attn_1 = make_attn(block_in, attn_type=attn_type) |
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self.mid.block_2 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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dropout=dropout) |
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|
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# end |
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self.norm_out = Normalize(block_in) |
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self.conv_out = comfy.ops.Conv2d(block_in, |
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2*z_channels if double_z else z_channels, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
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|
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def forward(self, x): |
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# timestep embedding |
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temb = None |
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pad = (0,1,0,1) |
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x = torch.nn.functional.pad(x, pad, mode="constant", value=0) |
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already_padded = True |
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# downsampling |
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h = self.conv_in(x) |
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for i_level in range(self.num_resolutions): |
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for i_block in range(self.num_res_blocks): |
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h = self.down[i_level].block[i_block](h, temb) |
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if len(self.down[i_level].attn) > 0: |
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h = self.down[i_level].attn[i_block](h) |
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if i_level != self.num_resolutions-1: |
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h = self.down[i_level].downsample(h, already_padded) |
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already_padded = False |
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|
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# middle |
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h = self.mid.block_1(h, temb) |
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h = self.mid.attn_1(h) |
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h = self.mid.block_2(h, temb) |
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|
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# end |
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h = self.norm_out(h) |
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h = nonlinearity(h) |
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h = self.conv_out(h) |
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return h |
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|
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|
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class Decoder(nn.Module): |
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def __init__(self, *, ch, out_ch, ch_mult=(1,2,4,8), num_res_blocks, |
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attn_resolutions, dropout=0.0, resamp_with_conv=True, in_channels, |
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resolution, z_channels, give_pre_end=False, tanh_out=False, use_linear_attn=False, |
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attn_type="vanilla", **ignorekwargs): |
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super().__init__() |
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if use_linear_attn: attn_type = "linear" |
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self.ch = ch |
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self.temb_ch = 0 |
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self.num_resolutions = len(ch_mult) |
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self.num_res_blocks = num_res_blocks |
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self.resolution = resolution |
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self.in_channels = in_channels |
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self.give_pre_end = give_pre_end |
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self.tanh_out = tanh_out |
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|
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# compute in_ch_mult, block_in and curr_res at lowest res |
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in_ch_mult = (1,)+tuple(ch_mult) |
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block_in = ch*ch_mult[self.num_resolutions-1] |
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curr_res = resolution // 2**(self.num_resolutions-1) |
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self.z_shape = (1,z_channels,curr_res,curr_res) |
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print("Working with z of shape {} = {} dimensions.".format( |
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self.z_shape, np.prod(self.z_shape))) |
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|
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# z to block_in |
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self.conv_in = comfy.ops.Conv2d(z_channels, |
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block_in, |
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kernel_size=3, |
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stride=1, |
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padding=1) |
|
|
|
# middle |
|
self.mid = nn.Module() |
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self.mid.block_1 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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dropout=dropout) |
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self.mid.attn_1 = make_attn(block_in, attn_type=attn_type) |
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self.mid.block_2 = ResnetBlock(in_channels=block_in, |
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out_channels=block_in, |
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temb_channels=self.temb_ch, |
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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) |
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curr_res = curr_res * 2 |
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self.up.insert(0, up) # prepend to get consistent order |
|
|
|
# end |
|
self.norm_out = Normalize(block_in) |
|
self.conv_out = comfy.ops.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
|
|
|