Spaces:
Runtime error
Runtime error
""" ReXNet | |
A PyTorch impl of `ReXNet: Diminishing Representational Bottleneck on Convolutional Neural Network` - | |
https://arxiv.org/abs/2007.00992 | |
Adapted from original impl at https://github.com/clovaai/rexnet | |
Copyright (c) 2020-present NAVER Corp. MIT license | |
Changes for timm, feature extraction, and rounded channel variant hacked together by Ross Wightman | |
Copyright 2020 Ross Wightman | |
""" | |
import torch.nn as nn | |
from functools import partial | |
from math import ceil | |
from timm.data import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD | |
from .helpers import build_model_with_cfg | |
from .layers import ClassifierHead, create_act_layer, ConvBnAct, DropPath, make_divisible, SEModule | |
from .registry import register_model | |
from .efficientnet_builder import efficientnet_init_weights | |
def _cfg(url=''): | |
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': 'stem.conv', 'classifier': 'head.fc', | |
} | |
default_cfgs = dict( | |
rexnet_100=_cfg( | |
url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rexnet/rexnetv1_100-1b4dddf4.pth'), | |
rexnet_130=_cfg( | |
url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rexnet/rexnetv1_130-590d768e.pth'), | |
rexnet_150=_cfg( | |
url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rexnet/rexnetv1_150-bd1a6aa8.pth'), | |
rexnet_200=_cfg( | |
url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rexnet/rexnetv1_200-8c0b7f2d.pth'), | |
rexnetr_100=_cfg( | |
url=''), | |
rexnetr_130=_cfg( | |
url=''), | |
rexnetr_150=_cfg( | |
url=''), | |
rexnetr_200=_cfg( | |
url=''), | |
) | |
SEWithNorm = partial(SEModule, norm_layer=nn.BatchNorm2d) | |
class LinearBottleneck(nn.Module): | |
def __init__(self, in_chs, out_chs, stride, exp_ratio=1.0, se_ratio=0., ch_div=1, | |
act_layer='swish', dw_act_layer='relu6', drop_path=None): | |
super(LinearBottleneck, self).__init__() | |
self.use_shortcut = stride == 1 and in_chs <= out_chs | |
self.in_channels = in_chs | |
self.out_channels = out_chs | |
if exp_ratio != 1.: | |
dw_chs = make_divisible(round(in_chs * exp_ratio), divisor=ch_div) | |
self.conv_exp = ConvBnAct(in_chs, dw_chs, act_layer=act_layer) | |
else: | |
dw_chs = in_chs | |
self.conv_exp = None | |
self.conv_dw = ConvBnAct(dw_chs, dw_chs, 3, stride=stride, groups=dw_chs, apply_act=False) | |
if se_ratio > 0: | |
self.se = SEWithNorm(dw_chs, rd_channels=make_divisible(int(dw_chs * se_ratio), ch_div)) | |
else: | |
self.se = None | |
self.act_dw = create_act_layer(dw_act_layer) | |
self.conv_pwl = ConvBnAct(dw_chs, out_chs, 1, apply_act=False) | |
self.drop_path = drop_path | |
def feat_channels(self, exp=False): | |
return self.conv_dw.out_channels if exp else self.out_channels | |
def forward(self, x): | |
shortcut = x | |
if self.conv_exp is not None: | |
x = self.conv_exp(x) | |
x = self.conv_dw(x) | |
if self.se is not None: | |
x = self.se(x) | |
x = self.act_dw(x) | |
x = self.conv_pwl(x) | |
if self.use_shortcut: | |
if self.drop_path is not None: | |
x = self.drop_path(x) | |
x[:, 0:self.in_channels] += shortcut | |
return x | |
def _block_cfg(width_mult=1.0, depth_mult=1.0, initial_chs=16, final_chs=180, se_ratio=0., ch_div=1): | |
layers = [1, 2, 2, 3, 3, 5] | |
strides = [1, 2, 2, 2, 1, 2] | |
layers = [ceil(element * depth_mult) for element in layers] | |
strides = sum([[element] + [1] * (layers[idx] - 1) for idx, element in enumerate(strides)], []) | |
exp_ratios = [1] * layers[0] + [6] * sum(layers[1:]) | |
depth = sum(layers[:]) * 3 | |
base_chs = initial_chs / width_mult if width_mult < 1.0 else initial_chs | |
# The following channel configuration is a simple instance to make each layer become an expand layer. | |
out_chs_list = [] | |
for i in range(depth // 3): | |
out_chs_list.append(make_divisible(round(base_chs * width_mult), divisor=ch_div)) | |
base_chs += final_chs / (depth // 3 * 1.0) | |
se_ratios = [0.] * (layers[0] + layers[1]) + [se_ratio] * sum(layers[2:]) | |
return list(zip(out_chs_list, exp_ratios, strides, se_ratios)) | |
def _build_blocks( | |
block_cfg, prev_chs, width_mult, ch_div=1, act_layer='swish', dw_act_layer='relu6', drop_path_rate=0.): | |
feat_chs = [prev_chs] | |
feature_info = [] | |
curr_stride = 2 | |
features = [] | |
num_blocks = len(block_cfg) | |
for block_idx, (chs, exp_ratio, stride, se_ratio) in enumerate(block_cfg): | |
if stride > 1: | |
fname = 'stem' if block_idx == 0 else f'features.{block_idx - 1}' | |
feature_info += [dict(num_chs=feat_chs[-1], reduction=curr_stride, module=fname)] | |
curr_stride *= stride | |
block_dpr = drop_path_rate * block_idx / (num_blocks - 1) # stochastic depth linear decay rule | |
drop_path = DropPath(block_dpr) if block_dpr > 0. else None | |
features.append(LinearBottleneck( | |
in_chs=prev_chs, out_chs=chs, exp_ratio=exp_ratio, stride=stride, se_ratio=se_ratio, | |
ch_div=ch_div, act_layer=act_layer, dw_act_layer=dw_act_layer, drop_path=drop_path)) | |
prev_chs = chs | |
feat_chs += [features[-1].feat_channels()] | |
pen_chs = make_divisible(1280 * width_mult, divisor=ch_div) | |
feature_info += [dict(num_chs=feat_chs[-1], reduction=curr_stride, module=f'features.{len(features) - 1}')] | |
features.append(ConvBnAct(prev_chs, pen_chs, act_layer=act_layer)) | |
return features, feature_info | |
class ReXNetV1(nn.Module): | |
def __init__(self, in_chans=3, num_classes=1000, global_pool='avg', output_stride=32, | |
initial_chs=16, final_chs=180, width_mult=1.0, depth_mult=1.0, se_ratio=1/12., | |
ch_div=1, act_layer='swish', dw_act_layer='relu6', drop_rate=0.2, drop_path_rate=0.): | |
super(ReXNetV1, self).__init__() | |
self.drop_rate = drop_rate | |
self.num_classes = num_classes | |
assert output_stride == 32 # FIXME support dilation | |
stem_base_chs = 32 / width_mult if width_mult < 1.0 else 32 | |
stem_chs = make_divisible(round(stem_base_chs * width_mult), divisor=ch_div) | |
self.stem = ConvBnAct(in_chans, stem_chs, 3, stride=2, act_layer=act_layer) | |
block_cfg = _block_cfg(width_mult, depth_mult, initial_chs, final_chs, se_ratio, ch_div) | |
features, self.feature_info = _build_blocks( | |
block_cfg, stem_chs, width_mult, ch_div, act_layer, dw_act_layer, drop_path_rate) | |
self.num_features = features[-1].out_channels | |
self.features = nn.Sequential(*features) | |
self.head = ClassifierHead(self.num_features, num_classes, global_pool, drop_rate) | |
efficientnet_init_weights(self) | |
def get_classifier(self): | |
return self.head.fc | |
def reset_classifier(self, num_classes, global_pool='avg'): | |
self.head = ClassifierHead(self.num_features, num_classes, pool_type=global_pool, drop_rate=self.drop_rate) | |
def forward_features(self, x): | |
x = self.stem(x) | |
x = self.features(x) | |
return x | |
def forward(self, x): | |
x = self.forward_features(x) | |
x = self.head(x) | |
return x | |
def _create_rexnet(variant, pretrained, **kwargs): | |
feature_cfg = dict(flatten_sequential=True) | |
return build_model_with_cfg( | |
ReXNetV1, variant, pretrained, | |
default_cfg=default_cfgs[variant], | |
feature_cfg=feature_cfg, | |
**kwargs) | |
def rexnet_100(pretrained=False, **kwargs): | |
"""ReXNet V1 1.0x""" | |
return _create_rexnet('rexnet_100', pretrained, **kwargs) | |
def rexnet_130(pretrained=False, **kwargs): | |
"""ReXNet V1 1.3x""" | |
return _create_rexnet('rexnet_130', pretrained, width_mult=1.3, **kwargs) | |
def rexnet_150(pretrained=False, **kwargs): | |
"""ReXNet V1 1.5x""" | |
return _create_rexnet('rexnet_150', pretrained, width_mult=1.5, **kwargs) | |
def rexnet_200(pretrained=False, **kwargs): | |
"""ReXNet V1 2.0x""" | |
return _create_rexnet('rexnet_200', pretrained, width_mult=2.0, **kwargs) | |
def rexnetr_100(pretrained=False, **kwargs): | |
"""ReXNet V1 1.0x w/ rounded (mod 8) channels""" | |
return _create_rexnet('rexnetr_100', pretrained, ch_div=8, **kwargs) | |
def rexnetr_130(pretrained=False, **kwargs): | |
"""ReXNet V1 1.3x w/ rounded (mod 8) channels""" | |
return _create_rexnet('rexnetr_130', pretrained, width_mult=1.3, ch_div=8, **kwargs) | |
def rexnetr_150(pretrained=False, **kwargs): | |
"""ReXNet V1 1.5x w/ rounded (mod 8) channels""" | |
return _create_rexnet('rexnetr_150', pretrained, width_mult=1.5, ch_div=8, **kwargs) | |
def rexnetr_200(pretrained=False, **kwargs): | |
"""ReXNet V1 2.0x w/ rounded (mod 8) channels""" | |
return _create_rexnet('rexnetr_200', pretrained, width_mult=2.0, ch_div=8, **kwargs) | |