Take some code from chainner to implement ESRGAN and other upscale models.
This commit is contained in:
201
comfy_extras/chainner_models/architecture/timm/LICENSE
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201
comfy_extras/chainner_models/architecture/timm/LICENSE
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@@ -0,0 +1,201 @@
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Copyright 2019 Ross Wightman
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223
comfy_extras/chainner_models/architecture/timm/drop.py
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223
comfy_extras/chainner_models/architecture/timm/drop.py
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|
||||
""" DropBlock, DropPath
|
||||
|
||||
PyTorch implementations of DropBlock and DropPath (Stochastic Depth) regularization layers.
|
||||
|
||||
Papers:
|
||||
DropBlock: A regularization method for convolutional networks (https://arxiv.org/abs/1810.12890)
|
||||
|
||||
Deep Networks with Stochastic Depth (https://arxiv.org/abs/1603.09382)
|
||||
|
||||
Code:
|
||||
DropBlock impl inspired by two Tensorflow impl that I liked:
|
||||
- https://github.com/tensorflow/tpu/blob/master/models/official/resnet/resnet_model.py#L74
|
||||
- https://github.com/clovaai/assembled-cnn/blob/master/nets/blocks.py
|
||||
|
||||
Hacked together by / Copyright 2020 Ross Wightman
|
||||
"""
|
||||
import torch
|
||||
import torch.nn as nn
|
||||
import torch.nn.functional as F
|
||||
|
||||
|
||||
def drop_block_2d(
|
||||
x,
|
||||
drop_prob: float = 0.1,
|
||||
block_size: int = 7,
|
||||
gamma_scale: float = 1.0,
|
||||
with_noise: bool = False,
|
||||
inplace: bool = False,
|
||||
batchwise: bool = False,
|
||||
):
|
||||
"""DropBlock. See https://arxiv.org/pdf/1810.12890.pdf
|
||||
|
||||
DropBlock with an experimental gaussian noise option. This layer has been tested on a few training
|
||||
runs with success, but needs further validation and possibly optimization for lower runtime impact.
|
||||
"""
|
||||
_, C, H, W = x.shape
|
||||
total_size = W * H
|
||||
clipped_block_size = min(block_size, min(W, H))
|
||||
# seed_drop_rate, the gamma parameter
|
||||
gamma = (
|
||||
gamma_scale
|
||||
* drop_prob
|
||||
* total_size
|
||||
/ clipped_block_size**2
|
||||
/ ((W - block_size + 1) * (H - block_size + 1))
|
||||
)
|
||||
|
||||
# Forces the block to be inside the feature map.
|
||||
w_i, h_i = torch.meshgrid(
|
||||
torch.arange(W).to(x.device), torch.arange(H).to(x.device)
|
||||
)
|
||||
valid_block = (
|
||||
(w_i >= clipped_block_size // 2) & (w_i < W - (clipped_block_size - 1) // 2)
|
||||
) & ((h_i >= clipped_block_size // 2) & (h_i < H - (clipped_block_size - 1) // 2))
|
||||
valid_block = torch.reshape(valid_block, (1, 1, H, W)).to(dtype=x.dtype)
|
||||
|
||||
if batchwise:
|
||||
# one mask for whole batch, quite a bit faster
|
||||
uniform_noise = torch.rand((1, C, H, W), dtype=x.dtype, device=x.device)
|
||||
else:
|
||||
uniform_noise = torch.rand_like(x)
|
||||
block_mask = ((2 - gamma - valid_block + uniform_noise) >= 1).to(dtype=x.dtype)
|
||||
block_mask = -F.max_pool2d(
|
||||
-block_mask,
|
||||
kernel_size=clipped_block_size, # block_size,
|
||||
stride=1,
|
||||
padding=clipped_block_size // 2,
|
||||
)
|
||||
|
||||
if with_noise:
|
||||
normal_noise = (
|
||||
torch.randn((1, C, H, W), dtype=x.dtype, device=x.device)
|
||||
if batchwise
|
||||
else torch.randn_like(x)
|
||||
)
|
||||
if inplace:
|
||||
x.mul_(block_mask).add_(normal_noise * (1 - block_mask))
|
||||
else:
|
||||
x = x * block_mask + normal_noise * (1 - block_mask)
|
||||
else:
|
||||
normalize_scale = (
|
||||
block_mask.numel() / block_mask.to(dtype=torch.float32).sum().add(1e-7)
|
||||
).to(x.dtype)
|
||||
if inplace:
|
||||
x.mul_(block_mask * normalize_scale)
|
||||
else:
|
||||
x = x * block_mask * normalize_scale
|
||||
return x
|
||||
|
||||
|
||||
def drop_block_fast_2d(
|
||||
x: torch.Tensor,
|
||||
drop_prob: float = 0.1,
|
||||
block_size: int = 7,
|
||||
gamma_scale: float = 1.0,
|
||||
with_noise: bool = False,
|
||||
inplace: bool = False,
|
||||
):
|
||||
"""DropBlock. See https://arxiv.org/pdf/1810.12890.pdf
|
||||
|
||||
DropBlock with an experimental gaussian noise option. Simplied from above without concern for valid
|
||||
block mask at edges.
|
||||
"""
|
||||
_, _, H, W = x.shape
|
||||
total_size = W * H
|
||||
clipped_block_size = min(block_size, min(W, H))
|
||||
gamma = (
|
||||
gamma_scale
|
||||
* drop_prob
|
||||
* total_size
|
||||
/ clipped_block_size**2
|
||||
/ ((W - block_size + 1) * (H - block_size + 1))
|
||||
)
|
||||
|
||||
block_mask = torch.empty_like(x).bernoulli_(gamma)
|
||||
block_mask = F.max_pool2d(
|
||||
block_mask.to(x.dtype),
|
||||
kernel_size=clipped_block_size,
|
||||
stride=1,
|
||||
padding=clipped_block_size // 2,
|
||||
)
|
||||
|
||||
if with_noise:
|
||||
normal_noise = torch.empty_like(x).normal_()
|
||||
if inplace:
|
||||
x.mul_(1.0 - block_mask).add_(normal_noise * block_mask)
|
||||
else:
|
||||
x = x * (1.0 - block_mask) + normal_noise * block_mask
|
||||
else:
|
||||
block_mask = 1 - block_mask
|
||||
normalize_scale = (
|
||||
block_mask.numel() / block_mask.to(dtype=torch.float32).sum().add(1e-6)
|
||||
).to(dtype=x.dtype)
|
||||
if inplace:
|
||||
x.mul_(block_mask * normalize_scale)
|
||||
else:
|
||||
x = x * block_mask * normalize_scale
|
||||
return x
|
||||
|
||||
|
||||
class DropBlock2d(nn.Module):
|
||||
"""DropBlock. See https://arxiv.org/pdf/1810.12890.pdf"""
|
||||
|
||||
def __init__(
|
||||
self,
|
||||
drop_prob: float = 0.1,
|
||||
block_size: int = 7,
|
||||
gamma_scale: float = 1.0,
|
||||
with_noise: bool = False,
|
||||
inplace: bool = False,
|
||||
batchwise: bool = False,
|
||||
fast: bool = True,
|
||||
):
|
||||
super(DropBlock2d, self).__init__()
|
||||
self.drop_prob = drop_prob
|
||||
self.gamma_scale = gamma_scale
|
||||
self.block_size = block_size
|
||||
self.with_noise = with_noise
|
||||
self.inplace = inplace
|
||||
self.batchwise = batchwise
|
||||
self.fast = fast # FIXME finish comparisons of fast vs not
|
||||
|
||||
def forward(self, x):
|
||||
if not self.training or not self.drop_prob:
|
||||
return x
|
||||
if self.fast:
|
||||
return drop_block_fast_2d(
|
||||
x,
|
||||
self.drop_prob,
|
||||
self.block_size,
|
||||
self.gamma_scale,
|
||||
self.with_noise,
|
||||
self.inplace,
|
||||
)
|
||||
else:
|
||||
return drop_block_2d(
|
||||
x,
|
||||
self.drop_prob,
|
||||
self.block_size,
|
||||
self.gamma_scale,
|
||||
self.with_noise,
|
||||
self.inplace,
|
||||
self.batchwise,
|
||||
)
|
||||
|
||||
|
||||
def drop_path(
|
||||
x, drop_prob: float = 0.0, training: bool = False, scale_by_keep: bool = True
|
||||
):
|
||||
"""Drop paths (Stochastic Depth) per sample (when applied in main path of residual blocks).
|
||||
|
||||
This is the same as the DropConnect impl I created for EfficientNet, etc networks, however,
|
||||
the original name is misleading as 'Drop Connect' is a different form of dropout in a separate paper...
|
||||
See discussion: https://github.com/tensorflow/tpu/issues/494#issuecomment-532968956 ... I've opted for
|
||||
changing the layer and argument names to 'drop path' rather than mix DropConnect as a layer name and use
|
||||
'survival rate' as the argument.
|
||||
|
||||
"""
|
||||
if drop_prob == 0.0 or not training:
|
||||
return x
|
||||
keep_prob = 1 - drop_prob
|
||||
shape = (x.shape[0],) + (1,) * (
|
||||
x.ndim - 1
|
||||
) # work with diff dim tensors, not just 2D ConvNets
|
||||
random_tensor = x.new_empty(shape).bernoulli_(keep_prob)
|
||||
if keep_prob > 0.0 and scale_by_keep:
|
||||
random_tensor.div_(keep_prob)
|
||||
return x * random_tensor
|
||||
|
||||
|
||||
class DropPath(nn.Module):
|
||||
"""Drop paths (Stochastic Depth) per sample (when applied in main path of residual blocks)."""
|
||||
|
||||
def __init__(self, drop_prob: float = 0.0, scale_by_keep: bool = True):
|
||||
super(DropPath, self).__init__()
|
||||
self.drop_prob = drop_prob
|
||||
self.scale_by_keep = scale_by_keep
|
||||
|
||||
def forward(self, x):
|
||||
return drop_path(x, self.drop_prob, self.training, self.scale_by_keep)
|
||||
|
||||
def extra_repr(self):
|
||||
return f"drop_prob={round(self.drop_prob,3):0.3f}"
|
||||
31
comfy_extras/chainner_models/architecture/timm/helpers.py
Normal file
31
comfy_extras/chainner_models/architecture/timm/helpers.py
Normal file
@@ -0,0 +1,31 @@
|
||||
""" Layer/Module Helpers
|
||||
Hacked together by / Copyright 2020 Ross Wightman
|
||||
"""
|
||||
import collections.abc
|
||||
from itertools import repeat
|
||||
|
||||
|
||||
# From PyTorch internals
|
||||
def _ntuple(n):
|
||||
def parse(x):
|
||||
if isinstance(x, collections.abc.Iterable) and not isinstance(x, str):
|
||||
return x
|
||||
return tuple(repeat(x, n))
|
||||
|
||||
return parse
|
||||
|
||||
|
||||
to_1tuple = _ntuple(1)
|
||||
to_2tuple = _ntuple(2)
|
||||
to_3tuple = _ntuple(3)
|
||||
to_4tuple = _ntuple(4)
|
||||
to_ntuple = _ntuple
|
||||
|
||||
|
||||
def make_divisible(v, divisor=8, min_value=None, round_limit=0.9):
|
||||
min_value = min_value or divisor
|
||||
new_v = max(min_value, int(v + divisor / 2) // divisor * divisor)
|
||||
# Make sure that round down does not go down by more than 10%.
|
||||
if new_v < round_limit * v:
|
||||
new_v += divisor
|
||||
return new_v
|
||||
128
comfy_extras/chainner_models/architecture/timm/weight_init.py
Normal file
128
comfy_extras/chainner_models/architecture/timm/weight_init.py
Normal file
@@ -0,0 +1,128 @@
|
||||
import math
|
||||
import warnings
|
||||
|
||||
import torch
|
||||
from torch.nn.init import _calculate_fan_in_and_fan_out
|
||||
|
||||
|
||||
def _no_grad_trunc_normal_(tensor, mean, std, a, b):
|
||||
# Cut & paste from PyTorch official master until it's in a few official releases - RW
|
||||
# Method based on https://people.sc.fsu.edu/~jburkardt/presentations/truncated_normal.pdf
|
||||
def norm_cdf(x):
|
||||
# Computes standard normal cumulative distribution function
|
||||
return (1.0 + math.erf(x / math.sqrt(2.0))) / 2.0
|
||||
|
||||
if (mean < a - 2 * std) or (mean > b + 2 * std):
|
||||
warnings.warn(
|
||||
"mean is more than 2 std from [a, b] in nn.init.trunc_normal_. "
|
||||
"The distribution of values may be incorrect.",
|
||||
stacklevel=2,
|
||||
)
|
||||
|
||||
with torch.no_grad():
|
||||
# Values are generated by using a truncated uniform distribution and
|
||||
# then using the inverse CDF for the normal distribution.
|
||||
# Get upper and lower cdf values
|
||||
l = norm_cdf((a - mean) / std)
|
||||
u = norm_cdf((b - mean) / std)
|
||||
|
||||
# Uniformly fill tensor with values from [l, u], then translate to
|
||||
# [2l-1, 2u-1].
|
||||
tensor.uniform_(2 * l - 1, 2 * u - 1)
|
||||
|
||||
# Use inverse cdf transform for normal distribution to get truncated
|
||||
# standard normal
|
||||
tensor.erfinv_()
|
||||
|
||||
# Transform to proper mean, std
|
||||
tensor.mul_(std * math.sqrt(2.0))
|
||||
tensor.add_(mean)
|
||||
|
||||
# Clamp to ensure it's in the proper range
|
||||
tensor.clamp_(min=a, max=b)
|
||||
return tensor
|
||||
|
||||
|
||||
def trunc_normal_(
|
||||
tensor: torch.Tensor, mean=0.0, std=1.0, a=-2.0, b=2.0
|
||||
) -> torch.Tensor:
|
||||
r"""Fills the input Tensor with values drawn from a truncated
|
||||
normal distribution. The values are effectively drawn from the
|
||||
normal distribution :math:`\mathcal{N}(\text{mean}, \text{std}^2)`
|
||||
with values outside :math:`[a, b]` redrawn until they are within
|
||||
the bounds. The method used for generating the random values works
|
||||
best when :math:`a \leq \text{mean} \leq b`.
|
||||
|
||||
NOTE: this impl is similar to the PyTorch trunc_normal_, the bounds [a, b] are
|
||||
applied while sampling the normal with mean/std applied, therefore a, b args
|
||||
should be adjusted to match the range of mean, std args.
|
||||
|
||||
Args:
|
||||
tensor: an n-dimensional `torch.Tensor`
|
||||
mean: the mean of the normal distribution
|
||||
std: the standard deviation of the normal distribution
|
||||
a: the minimum cutoff value
|
||||
b: the maximum cutoff value
|
||||
Examples:
|
||||
>>> w = torch.empty(3, 5)
|
||||
>>> nn.init.trunc_normal_(w)
|
||||
"""
|
||||
return _no_grad_trunc_normal_(tensor, mean, std, a, b)
|
||||
|
||||
|
||||
def trunc_normal_tf_(
|
||||
tensor: torch.Tensor, mean=0.0, std=1.0, a=-2.0, b=2.0
|
||||
) -> torch.Tensor:
|
||||
r"""Fills the input Tensor with values drawn from a truncated
|
||||
normal distribution. The values are effectively drawn from the
|
||||
normal distribution :math:`\mathcal{N}(\text{mean}, \text{std}^2)`
|
||||
with values outside :math:`[a, b]` redrawn until they are within
|
||||
the bounds. The method used for generating the random values works
|
||||
best when :math:`a \leq \text{mean} \leq b`.
|
||||
|
||||
NOTE: this 'tf' variant behaves closer to Tensorflow / JAX impl where the
|
||||
bounds [a, b] are applied when sampling the normal distribution with mean=0, std=1.0
|
||||
and the result is subsquently scaled and shifted by the mean and std args.
|
||||
|
||||
Args:
|
||||
tensor: an n-dimensional `torch.Tensor`
|
||||
mean: the mean of the normal distribution
|
||||
std: the standard deviation of the normal distribution
|
||||
a: the minimum cutoff value
|
||||
b: the maximum cutoff value
|
||||
Examples:
|
||||
>>> w = torch.empty(3, 5)
|
||||
>>> nn.init.trunc_normal_(w)
|
||||
"""
|
||||
_no_grad_trunc_normal_(tensor, 0, 1.0, a, b)
|
||||
with torch.no_grad():
|
||||
tensor.mul_(std).add_(mean)
|
||||
return tensor
|
||||
|
||||
|
||||
def variance_scaling_(tensor, scale=1.0, mode="fan_in", distribution="normal"):
|
||||
fan_in, fan_out = _calculate_fan_in_and_fan_out(tensor)
|
||||
if mode == "fan_in":
|
||||
denom = fan_in
|
||||
elif mode == "fan_out":
|
||||
denom = fan_out
|
||||
elif mode == "fan_avg":
|
||||
denom = (fan_in + fan_out) / 2
|
||||
|
||||
variance = scale / denom # type: ignore
|
||||
|
||||
if distribution == "truncated_normal":
|
||||
# constant is stddev of standard normal truncated to (-2, 2)
|
||||
trunc_normal_tf_(tensor, std=math.sqrt(variance) / 0.87962566103423978)
|
||||
elif distribution == "normal":
|
||||
tensor.normal_(std=math.sqrt(variance))
|
||||
elif distribution == "uniform":
|
||||
bound = math.sqrt(3 * variance)
|
||||
# pylint: disable=invalid-unary-operand-type
|
||||
tensor.uniform_(-bound, bound)
|
||||
else:
|
||||
raise ValueError(f"invalid distribution {distribution}")
|
||||
|
||||
|
||||
def lecun_normal_(tensor):
|
||||
variance_scaling_(tensor, mode="fan_in", distribution="truncated_normal")
|
||||
Reference in New Issue
Block a user