pytorch-image-models/timm/models/repghost.py

482 lines
16 KiB
Python

"""
An implementation of RepGhostNet Model as defined in:
RepGhost: A Hardware-Efficient Ghost Module via Re-parameterization. https://arxiv.org/abs/2211.06088
Original implementation: https://github.com/ChengpengChen/RepGhost
"""
import copy
from functools import partial
from typing import Optional
import torch
import torch.nn as nn
import torch.nn.functional as F
from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD
from timm.layers import SelectAdaptivePool2d, Linear, make_divisible
from ._builder import build_model_with_cfg
from ._efficientnet_blocks import SqueezeExcite, ConvBnAct
from ._manipulate import checkpoint_seq
from ._registry import register_model, generate_default_cfgs
__all__ = ['RepGhostNet']
_SE_LAYER = partial(SqueezeExcite, gate_layer='hard_sigmoid', rd_round_fn=partial(make_divisible, divisor=4))
class RepGhostModule(nn.Module):
def __init__(
self,
in_chs,
out_chs,
kernel_size=1,
dw_size=3,
stride=1,
relu=True,
reparam=True,
):
super(RepGhostModule, self).__init__()
self.out_chs = out_chs
init_chs = out_chs
new_chs = out_chs
self.primary_conv = nn.Sequential(
nn.Conv2d(in_chs, init_chs, kernel_size, stride, kernel_size // 2, bias=False),
nn.BatchNorm2d(init_chs),
nn.ReLU(inplace=True) if relu else nn.Identity(),
)
fusion_conv = []
fusion_bn = []
if reparam:
fusion_conv.append(nn.Identity())
fusion_bn.append(nn.BatchNorm2d(init_chs))
self.fusion_conv = nn.Sequential(*fusion_conv)
self.fusion_bn = nn.Sequential(*fusion_bn)
self.cheap_operation = nn.Sequential(
nn.Conv2d(init_chs, new_chs, dw_size, 1, dw_size//2, groups=init_chs, bias=False),
nn.BatchNorm2d(new_chs),
# nn.ReLU(inplace=True) if relu else nn.Identity(),
)
self.relu = nn.ReLU(inplace=False) if relu else nn.Identity()
def forward(self, x):
x1 = self.primary_conv(x)
x2 = self.cheap_operation(x1)
for conv, bn in zip(self.fusion_conv, self.fusion_bn):
x2 = x2 + bn(conv(x1))
return self.relu(x2)
def get_equivalent_kernel_bias(self):
kernel3x3, bias3x3 = self._fuse_bn_tensor(self.cheap_operation[0], self.cheap_operation[1])
for conv, bn in zip(self.fusion_conv, self.fusion_bn):
kernel, bias = self._fuse_bn_tensor(conv, bn, kernel3x3.shape[0], kernel3x3.device)
kernel3x3 += self._pad_1x1_to_3x3_tensor(kernel)
bias3x3 += bias
return kernel3x3, bias3x3
@staticmethod
def _pad_1x1_to_3x3_tensor(kernel1x1):
if kernel1x1 is None:
return 0
else:
return torch.nn.functional.pad(kernel1x1, [1, 1, 1, 1])
@staticmethod
def _fuse_bn_tensor(conv, bn, in_channels=None, device=None):
in_channels = in_channels if in_channels else bn.running_mean.shape[0]
device = device if device else bn.weight.device
if isinstance(conv, nn.Conv2d):
kernel = conv.weight
assert conv.bias is None
else:
assert isinstance(conv, nn.Identity)
kernel = torch.ones(in_channels, 1, 1, 1, device=device)
if isinstance(bn, nn.BatchNorm2d):
running_mean = bn.running_mean
running_var = bn.running_var
gamma = bn.weight
beta = bn.bias
eps = bn.eps
std = (running_var + eps).sqrt()
t = (gamma / std).reshape(-1, 1, 1, 1)
return kernel * t, beta - running_mean * gamma / std
assert isinstance(bn, nn.Identity)
return kernel, torch.zeros(in_channels).to(kernel.device)
def switch_to_deploy(self):
if len(self.fusion_conv) == 0 and len(self.fusion_bn) == 0:
return
kernel, bias = self.get_equivalent_kernel_bias()
self.cheap_operation = nn.Conv2d(
in_channels=self.cheap_operation[0].in_channels,
out_channels=self.cheap_operation[0].out_channels,
kernel_size=self.cheap_operation[0].kernel_size,
padding=self.cheap_operation[0].padding,
dilation=self.cheap_operation[0].dilation,
groups=self.cheap_operation[0].groups,
bias=True)
self.cheap_operation.weight.data = kernel
self.cheap_operation.bias.data = bias
self.__delattr__('fusion_conv')
self.__delattr__('fusion_bn')
self.fusion_conv = []
self.fusion_bn = []
def reparameterize(self):
self.switch_to_deploy()
class RepGhostBottleneck(nn.Module):
""" RepGhost bottleneck w/ optional SE"""
def __init__(
self,
in_chs,
mid_chs,
out_chs,
dw_kernel_size=3,
stride=1,
act_layer=nn.ReLU,
se_ratio=0.,
reparam=True,
):
super(RepGhostBottleneck, self).__init__()
has_se = se_ratio is not None and se_ratio > 0.
self.stride = stride
# Point-wise expansion
self.ghost1 = RepGhostModule(in_chs, mid_chs, relu=True, reparam=reparam)
# Depth-wise convolution
if self.stride > 1:
self.conv_dw = nn.Conv2d(
mid_chs, mid_chs, dw_kernel_size, stride=stride,
padding=(dw_kernel_size-1)//2, groups=mid_chs, bias=False)
self.bn_dw = nn.BatchNorm2d(mid_chs)
else:
self.conv_dw = None
self.bn_dw = None
# Squeeze-and-excitation
self.se = _SE_LAYER(mid_chs, rd_ratio=se_ratio) if has_se else None
# Point-wise linear projection
self.ghost2 = RepGhostModule(mid_chs, out_chs, relu=False, reparam=reparam)
# shortcut
if in_chs == out_chs and self.stride == 1:
self.shortcut = nn.Sequential()
else:
self.shortcut = nn.Sequential(
nn.Conv2d(
in_chs, in_chs, dw_kernel_size, stride=stride,
padding=(dw_kernel_size-1)//2, groups=in_chs, bias=False),
nn.BatchNorm2d(in_chs),
nn.Conv2d(in_chs, out_chs, 1, stride=1, padding=0, bias=False),
nn.BatchNorm2d(out_chs),
)
def forward(self, x):
shortcut = x
# 1st ghost bottleneck
x = self.ghost1(x)
# Depth-wise convolution
if self.conv_dw is not None:
x = self.conv_dw(x)
x = self.bn_dw(x)
# Squeeze-and-excitation
if self.se is not None:
x = self.se(x)
# 2nd ghost bottleneck
x = self.ghost2(x)
x += self.shortcut(shortcut)
return x
class RepGhostNet(nn.Module):
def __init__(
self,
cfgs,
num_classes=1000,
width=1.0,
in_chans=3,
output_stride=32,
global_pool='avg',
drop_rate=0.2,
reparam=True,
):
super(RepGhostNet, self).__init__()
# setting of inverted residual blocks
assert output_stride == 32, 'only output_stride==32 is valid, dilation not supported'
self.cfgs = cfgs
self.num_classes = num_classes
self.drop_rate = drop_rate
self.grad_checkpointing = False
self.feature_info = []
# building first layer
stem_chs = make_divisible(16 * width, 4)
self.conv_stem = nn.Conv2d(in_chans, stem_chs, 3, 2, 1, bias=False)
self.feature_info.append(dict(num_chs=stem_chs, reduction=2, module=f'conv_stem'))
self.bn1 = nn.BatchNorm2d(stem_chs)
self.act1 = nn.ReLU(inplace=True)
prev_chs = stem_chs
# building inverted residual blocks
stages = nn.ModuleList([])
block = RepGhostBottleneck
stage_idx = 0
net_stride = 2
for cfg in self.cfgs:
layers = []
s = 1
for k, exp_size, c, se_ratio, s in cfg:
out_chs = make_divisible(c * width, 4)
mid_chs = make_divisible(exp_size * width, 4)
layers.append(block(prev_chs, mid_chs, out_chs, k, s, se_ratio=se_ratio, reparam=reparam))
prev_chs = out_chs
if s > 1:
net_stride *= 2
self.feature_info.append(dict(
num_chs=prev_chs, reduction=net_stride, module=f'blocks.{stage_idx}'))
stages.append(nn.Sequential(*layers))
stage_idx += 1
out_chs = make_divisible(exp_size * width * 2, 4)
stages.append(nn.Sequential(ConvBnAct(prev_chs, out_chs, 1)))
self.pool_dim = prev_chs = out_chs
self.blocks = nn.Sequential(*stages)
# building last several layers
self.num_features = prev_chs
self.head_hidden_size = out_chs = 1280
self.global_pool = SelectAdaptivePool2d(pool_type=global_pool)
self.conv_head = nn.Conv2d(prev_chs, out_chs, 1, 1, 0, bias=True)
self.act2 = nn.ReLU(inplace=True)
self.flatten = nn.Flatten(1) if global_pool else nn.Identity() # don't flatten if pooling disabled
self.classifier = Linear(out_chs, num_classes) if num_classes > 0 else nn.Identity()
@torch.jit.ignore
def group_matcher(self, coarse=False):
matcher = dict(
stem=r'^conv_stem|bn1',
blocks=[
(r'^blocks\.(\d+)' if coarse else r'^blocks\.(\d+)\.(\d+)', None),
(r'conv_head', (99999,))
]
)
return matcher
@torch.jit.ignore
def set_grad_checkpointing(self, enable=True):
self.grad_checkpointing = enable
@torch.jit.ignore
def get_classifier(self) -> nn.Module:
return self.classifier
def reset_classifier(self, num_classes: int, global_pool: Optional[str] = None):
self.num_classes = num_classes
if global_pool is not None:
# NOTE: cannot meaningfully change pooling of efficient head after creation
self.global_pool = SelectAdaptivePool2d(pool_type=global_pool)
self.flatten = nn.Flatten(1) if global_pool else nn.Identity() # don't flatten if pooling disabled
self.classifier = Linear(self.head_hidden_size, num_classes) if num_classes > 0 else nn.Identity()
def forward_features(self, x):
x = self.conv_stem(x)
x = self.bn1(x)
x = self.act1(x)
if self.grad_checkpointing and not torch.jit.is_scripting():
x = checkpoint_seq(self.blocks, x, flatten=True)
else:
x = self.blocks(x)
return x
def forward_head(self, x, pre_logits: bool = False):
x = self.global_pool(x)
x = self.conv_head(x)
x = self.act2(x)
x = self.flatten(x)
if self.drop_rate > 0.:
x = F.dropout(x, p=self.drop_rate, training=self.training)
return x if pre_logits else self.classifier(x)
def forward(self, x):
x = self.forward_features(x)
x = self.forward_head(x)
return x
def convert_to_deploy(self):
repghost_model_convert(self, do_copy=False)
def repghost_model_convert(model: torch.nn.Module, save_path=None, do_copy=True):
"""
taken from from https://github.com/DingXiaoH/RepVGG/blob/main/repvgg.py
"""
if do_copy:
model = copy.deepcopy(model)
for module in model.modules():
if hasattr(module, 'switch_to_deploy'):
module.switch_to_deploy()
if save_path is not None:
torch.save(model.state_dict(), save_path)
return model
def _create_repghostnet(variant, width=1.0, pretrained=False, **kwargs):
"""
Constructs a RepGhostNet model
"""
cfgs = [
# k, t, c, SE, s
# stage1
[[3, 8, 16, 0, 1]],
# stage2
[[3, 24, 24, 0, 2]],
[[3, 36, 24, 0, 1]],
# stage3
[[5, 36, 40, 0.25, 2]],
[[5, 60, 40, 0.25, 1]],
# stage4
[[3, 120, 80, 0, 2]],
[[3, 100, 80, 0, 1],
[3, 120, 80, 0, 1],
[3, 120, 80, 0, 1],
[3, 240, 112, 0.25, 1],
[3, 336, 112, 0.25, 1]
],
# stage5
[[5, 336, 160, 0.25, 2]],
[[5, 480, 160, 0, 1],
[5, 480, 160, 0.25, 1],
[5, 480, 160, 0, 1],
[5, 480, 160, 0.25, 1]
]
]
model_kwargs = dict(
cfgs=cfgs,
width=width,
**kwargs,
)
return build_model_with_cfg(
RepGhostNet,
variant,
pretrained,
feature_cfg=dict(flatten_sequential=True),
**model_kwargs,
)
def _cfg(url='', **kwargs):
return {
'url': url, 'num_classes': 1000, 'input_size': (3, 224, 224), 'pool_size': (7, 7),
'crop_pct': 0.875, 'interpolation': 'bicubic',
'mean': IMAGENET_DEFAULT_MEAN, 'std': IMAGENET_DEFAULT_STD,
'first_conv': 'conv_stem', 'classifier': 'classifier',
**kwargs
}
default_cfgs = generate_default_cfgs({
'repghostnet_050.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_0_5x_43M_66.95.pth.tar'
),
'repghostnet_058.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_0_58x_60M_68.94.pth.tar'
),
'repghostnet_080.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_0_8x_96M_72.24.pth.tar'
),
'repghostnet_100.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_1_0x_142M_74.22.pth.tar'
),
'repghostnet_111.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_1_11x_170M_75.07.pth.tar'
),
'repghostnet_130.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_1_3x_231M_76.37.pth.tar'
),
'repghostnet_150.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_1_5x_301M_77.45.pth.tar'
),
'repghostnet_200.in1k': _cfg(
hf_hub_id='timm/',
# url='https://github.com/ChengpengChen/RepGhost/releases/download/RepGhost/repghostnet_2_0x_516M_78.81.pth.tar'
),
})
@register_model
def repghostnet_050(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-0.5x """
model = _create_repghostnet('repghostnet_050', width=0.5, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_058(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-0.58x """
model = _create_repghostnet('repghostnet_058', width=0.58, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_080(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-0.8x """
model = _create_repghostnet('repghostnet_080', width=0.8, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_100(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-1.0x """
model = _create_repghostnet('repghostnet_100', width=1.0, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_111(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-1.11x """
model = _create_repghostnet('repghostnet_111', width=1.11, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_130(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-1.3x """
model = _create_repghostnet('repghostnet_130', width=1.3, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_150(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-1.5x """
model = _create_repghostnet('repghostnet_150', width=1.5, pretrained=pretrained, **kwargs)
return model
@register_model
def repghostnet_200(pretrained=False, **kwargs) -> RepGhostNet:
""" RepGhostNet-2.0x """
model = _create_repghostnet('repghostnet_200', width=2.0, pretrained=pretrained, **kwargs)
return model