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779 lines
30 KiB
779 lines
30 KiB
"""Pre-Activation ResNet v2 with GroupNorm and Weight Standardization.
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A PyTorch implementation of ResNetV2 adapted from the Google Big-Transfoer (BiT) source code
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at https://github.com/google-research/big_transfer to match timm interfaces. The BiT weights have
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been included here as pretrained models from their original .NPZ checkpoints.
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Additionally, supports non pre-activation bottleneck for use as a backbone for Vision Transfomers (ViT) and
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extra padding support to allow porting of official Hybrid ResNet pretrained weights from
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https://github.com/google-research/vision_transformer
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Thanks to the Google team for the above two repositories and associated papers:
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* Big Transfer (BiT): General Visual Representation Learning - https://arxiv.org/abs/1912.11370
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* An Image is Worth 16x16 Words: Transformers for Image Recognition at Scale - https://arxiv.org/abs/2010.11929
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* Knowledge distillation: A good teacher is patient and consistent - https://arxiv.org/abs/2106.05237
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Original copyright of Google code below, modifications by Ross Wightman, Copyright 2020.
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"""
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# Copyright 2020 Google LLC
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#
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# Licensed under the Apache License, Version 2.0 (the "License");
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# you may not use this file except in compliance with the License.
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# You may obtain a copy of the License at
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#
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# http://www.apache.org/licenses/LICENSE-2.0
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#
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# Unless required by applicable law or agreed to in writing, software
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# distributed under the License is distributed on an "AS IS" BASIS,
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# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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# See the License for the specific language governing permissions and
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# limitations under the License.
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from collections import OrderedDict # pylint: disable=g-importing-member
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from functools import partial
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import torch
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import torch.nn as nn
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from timm.data import IMAGENET_INCEPTION_MEAN, IMAGENET_INCEPTION_STD
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from timm.layers import GroupNormAct, BatchNormAct2d, EvoNorm2dB0, EvoNorm2dS0, FilterResponseNormTlu2d, \
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ClassifierHead, DropPath, AvgPool2dSame, create_pool2d, StdConv2d, create_conv2d
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from ._builder import build_model_with_cfg
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from ._manipulate import checkpoint_seq, named_apply, adapt_input_conv
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from ._registry import register_model
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__all__ = ['ResNetV2'] # model_registry will add each entrypoint fn to this
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def _cfg(url='', **kwargs):
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return {
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'url': url,
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'num_classes': 1000, 'input_size': (3, 224, 224), 'pool_size': (7, 7),
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'crop_pct': 0.875, 'interpolation': 'bilinear',
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'mean': IMAGENET_INCEPTION_MEAN, 'std': IMAGENET_INCEPTION_STD,
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'first_conv': 'stem.conv', 'classifier': 'head.fc',
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**kwargs
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}
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default_cfgs = {
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# pretrained on imagenet21k, finetuned on imagenet1k
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'resnetv2_50x1_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R50x1-ILSVRC2012.npz',
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input_size=(3, 448, 448), pool_size=(14, 14), crop_pct=1.0, custom_load=True),
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'resnetv2_50x3_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R50x3-ILSVRC2012.npz',
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input_size=(3, 448, 448), pool_size=(14, 14), crop_pct=1.0, custom_load=True),
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'resnetv2_101x1_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R101x1-ILSVRC2012.npz',
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input_size=(3, 448, 448), pool_size=(14, 14), crop_pct=1.0, custom_load=True),
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'resnetv2_101x3_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R101x3-ILSVRC2012.npz',
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input_size=(3, 448, 448), pool_size=(14, 14), crop_pct=1.0, custom_load=True),
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'resnetv2_152x2_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R152x2-ILSVRC2012.npz',
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input_size=(3, 448, 448), pool_size=(14, 14), crop_pct=1.0, custom_load=True),
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'resnetv2_152x4_bitm': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R152x4-ILSVRC2012.npz',
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input_size=(3, 480, 480), pool_size=(15, 15), crop_pct=1.0, custom_load=True), # only one at 480x480?
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# trained on imagenet-21k
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'resnetv2_50x1_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R50x1.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_50x3_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R50x3.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_101x1_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R101x1.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_101x3_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R101x3.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_152x2_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R152x2.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_152x4_bitm_in21k': _cfg(
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url='https://storage.googleapis.com/bit_models/BiT-M-R152x4.npz',
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num_classes=21843, custom_load=True),
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'resnetv2_50x1_bit_distilled': _cfg(
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url='https://storage.googleapis.com/bit_models/distill/R50x1_224.npz',
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interpolation='bicubic', custom_load=True),
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'resnetv2_152x2_bit_teacher': _cfg(
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url='https://storage.googleapis.com/bit_models/distill/R152x2_T_224.npz',
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interpolation='bicubic', custom_load=True),
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'resnetv2_152x2_bit_teacher_384': _cfg(
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url='https://storage.googleapis.com/bit_models/distill/R152x2_T_384.npz',
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input_size=(3, 384, 384), pool_size=(12, 12), crop_pct=1.0, interpolation='bicubic', custom_load=True),
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'resnetv2_50': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rsb-weights/resnetv2_50_a1h-000cdf49.pth',
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interpolation='bicubic', crop_pct=0.95),
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'resnetv2_50d': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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'resnetv2_50t': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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'resnetv2_101': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-rsb-weights/resnetv2_101_a1h-5d01f016.pth',
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interpolation='bicubic', crop_pct=0.95),
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'resnetv2_101d': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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'resnetv2_152': _cfg(
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interpolation='bicubic'),
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'resnetv2_152d': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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'resnetv2_50d_gn': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-tpu-weights/resnetv2_50d_gn_ah-c415c11a.pth',
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interpolation='bicubic', first_conv='stem.conv1', test_input_size=(3, 288, 288), crop_pct=0.95),
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'resnetv2_50d_evob': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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'resnetv2_50d_evos': _cfg(
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url='https://github.com/rwightman/pytorch-image-models/releases/download/v0.1-tpu-weights/resnetv2_50d_evos_ah-7c4dd548.pth',
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interpolation='bicubic', first_conv='stem.conv1', test_input_size=(3, 288, 288), crop_pct=0.95),
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'resnetv2_50d_frn': _cfg(
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interpolation='bicubic', first_conv='stem.conv1'),
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}
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def make_div(v, divisor=8):
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min_value = divisor
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new_v = max(min_value, int(v + divisor / 2) // divisor * divisor)
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if new_v < 0.9 * v:
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new_v += divisor
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return new_v
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class PreActBottleneck(nn.Module):
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"""Pre-activation (v2) bottleneck block.
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Follows the implementation of "Identity Mappings in Deep Residual Networks":
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https://github.com/KaimingHe/resnet-1k-layers/blob/master/resnet-pre-act.lua
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Except it puts the stride on 3x3 conv when available.
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"""
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def __init__(
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self,
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in_chs,
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out_chs=None,
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bottle_ratio=0.25,
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stride=1,
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dilation=1,
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first_dilation=None,
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groups=1,
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act_layer=None,
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conv_layer=None,
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norm_layer=None,
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proj_layer=None,
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drop_path_rate=0.,
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):
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super().__init__()
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first_dilation = first_dilation or dilation
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conv_layer = conv_layer or StdConv2d
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norm_layer = norm_layer or partial(GroupNormAct, num_groups=32)
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out_chs = out_chs or in_chs
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mid_chs = make_div(out_chs * bottle_ratio)
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if proj_layer is not None:
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self.downsample = proj_layer(
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in_chs, out_chs, stride=stride, dilation=dilation, first_dilation=first_dilation, preact=True,
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conv_layer=conv_layer, norm_layer=norm_layer)
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else:
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self.downsample = None
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self.norm1 = norm_layer(in_chs)
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self.conv1 = conv_layer(in_chs, mid_chs, 1)
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self.norm2 = norm_layer(mid_chs)
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self.conv2 = conv_layer(mid_chs, mid_chs, 3, stride=stride, dilation=first_dilation, groups=groups)
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self.norm3 = norm_layer(mid_chs)
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self.conv3 = conv_layer(mid_chs, out_chs, 1)
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self.drop_path = DropPath(drop_path_rate) if drop_path_rate > 0 else nn.Identity()
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def zero_init_last(self):
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nn.init.zeros_(self.conv3.weight)
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def forward(self, x):
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x_preact = self.norm1(x)
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# shortcut branch
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shortcut = x
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if self.downsample is not None:
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shortcut = self.downsample(x_preact)
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# residual branch
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x = self.conv1(x_preact)
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x = self.conv2(self.norm2(x))
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x = self.conv3(self.norm3(x))
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x = self.drop_path(x)
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return x + shortcut
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class Bottleneck(nn.Module):
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"""Non Pre-activation bottleneck block, equiv to V1.5/V1b Bottleneck. Used for ViT.
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"""
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def __init__(
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self,
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in_chs,
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out_chs=None,
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bottle_ratio=0.25,
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stride=1,
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dilation=1,
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first_dilation=None,
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groups=1,
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act_layer=None,
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conv_layer=None,
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norm_layer=None,
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proj_layer=None,
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drop_path_rate=0.,
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):
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super().__init__()
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first_dilation = first_dilation or dilation
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act_layer = act_layer or nn.ReLU
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conv_layer = conv_layer or StdConv2d
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norm_layer = norm_layer or partial(GroupNormAct, num_groups=32)
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out_chs = out_chs or in_chs
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mid_chs = make_div(out_chs * bottle_ratio)
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if proj_layer is not None:
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self.downsample = proj_layer(
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in_chs, out_chs, stride=stride, dilation=dilation, preact=False,
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conv_layer=conv_layer, norm_layer=norm_layer)
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else:
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self.downsample = None
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self.conv1 = conv_layer(in_chs, mid_chs, 1)
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self.norm1 = norm_layer(mid_chs)
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self.conv2 = conv_layer(mid_chs, mid_chs, 3, stride=stride, dilation=first_dilation, groups=groups)
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self.norm2 = norm_layer(mid_chs)
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self.conv3 = conv_layer(mid_chs, out_chs, 1)
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self.norm3 = norm_layer(out_chs, apply_act=False)
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self.drop_path = DropPath(drop_path_rate) if drop_path_rate > 0 else nn.Identity()
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self.act3 = act_layer(inplace=True)
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def zero_init_last(self):
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if getattr(self.norm3, 'weight', None) is not None:
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nn.init.zeros_(self.norm3.weight)
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def forward(self, x):
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# shortcut branch
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shortcut = x
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if self.downsample is not None:
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shortcut = self.downsample(x)
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# residual
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x = self.conv1(x)
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x = self.norm1(x)
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x = self.conv2(x)
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x = self.norm2(x)
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x = self.conv3(x)
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x = self.norm3(x)
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x = self.drop_path(x)
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x = self.act3(x + shortcut)
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return x
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class DownsampleConv(nn.Module):
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def __init__(
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self, in_chs, out_chs, stride=1, dilation=1, first_dilation=None, preact=True,
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conv_layer=None, norm_layer=None):
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super(DownsampleConv, self).__init__()
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self.conv = conv_layer(in_chs, out_chs, 1, stride=stride)
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self.norm = nn.Identity() if preact else norm_layer(out_chs, apply_act=False)
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def forward(self, x):
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return self.norm(self.conv(x))
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class DownsampleAvg(nn.Module):
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def __init__(
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self, in_chs, out_chs, stride=1, dilation=1, first_dilation=None,
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preact=True, conv_layer=None, norm_layer=None):
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""" AvgPool Downsampling as in 'D' ResNet variants. This is not in RegNet space but I might experiment."""
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super(DownsampleAvg, self).__init__()
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avg_stride = stride if dilation == 1 else 1
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if stride > 1 or dilation > 1:
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avg_pool_fn = AvgPool2dSame if avg_stride == 1 and dilation > 1 else nn.AvgPool2d
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self.pool = avg_pool_fn(2, avg_stride, ceil_mode=True, count_include_pad=False)
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else:
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self.pool = nn.Identity()
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self.conv = conv_layer(in_chs, out_chs, 1, stride=1)
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self.norm = nn.Identity() if preact else norm_layer(out_chs, apply_act=False)
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def forward(self, x):
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return self.norm(self.conv(self.pool(x)))
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class ResNetStage(nn.Module):
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"""ResNet Stage."""
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def __init__(
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self,
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in_chs,
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out_chs,
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stride,
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dilation,
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depth,
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bottle_ratio=0.25,
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groups=1,
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avg_down=False,
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block_dpr=None,
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block_fn=PreActBottleneck,
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act_layer=None,
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conv_layer=None,
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norm_layer=None,
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**block_kwargs,
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):
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super(ResNetStage, self).__init__()
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first_dilation = 1 if dilation in (1, 2) else 2
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layer_kwargs = dict(act_layer=act_layer, conv_layer=conv_layer, norm_layer=norm_layer)
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proj_layer = DownsampleAvg if avg_down else DownsampleConv
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prev_chs = in_chs
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self.blocks = nn.Sequential()
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for block_idx in range(depth):
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drop_path_rate = block_dpr[block_idx] if block_dpr else 0.
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stride = stride if block_idx == 0 else 1
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self.blocks.add_module(str(block_idx), block_fn(
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prev_chs, out_chs, stride=stride, dilation=dilation, bottle_ratio=bottle_ratio, groups=groups,
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first_dilation=first_dilation, proj_layer=proj_layer, drop_path_rate=drop_path_rate,
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**layer_kwargs, **block_kwargs))
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prev_chs = out_chs
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first_dilation = dilation
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proj_layer = None
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def forward(self, x):
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x = self.blocks(x)
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return x
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def is_stem_deep(stem_type):
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return any([s in stem_type for s in ('deep', 'tiered')])
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def create_resnetv2_stem(
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in_chs,
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out_chs=64,
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stem_type='',
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preact=True,
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conv_layer=StdConv2d,
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norm_layer=partial(GroupNormAct, num_groups=32),
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):
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stem = OrderedDict()
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assert stem_type in ('', 'fixed', 'same', 'deep', 'deep_fixed', 'deep_same', 'tiered')
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# NOTE conv padding mode can be changed by overriding the conv_layer def
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if is_stem_deep(stem_type):
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# A 3 deep 3x3 conv stack as in ResNet V1D models
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if 'tiered' in stem_type:
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stem_chs = (3 * out_chs // 8, out_chs // 2) # 'T' resnets in resnet.py
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else:
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stem_chs = (out_chs // 2, out_chs // 2) # 'D' ResNets
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stem['conv1'] = conv_layer(in_chs, stem_chs[0], kernel_size=3, stride=2)
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stem['norm1'] = norm_layer(stem_chs[0])
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stem['conv2'] = conv_layer(stem_chs[0], stem_chs[1], kernel_size=3, stride=1)
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stem['norm2'] = norm_layer(stem_chs[1])
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stem['conv3'] = conv_layer(stem_chs[1], out_chs, kernel_size=3, stride=1)
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if not preact:
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stem['norm3'] = norm_layer(out_chs)
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else:
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# The usual 7x7 stem conv
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stem['conv'] = conv_layer(in_chs, out_chs, kernel_size=7, stride=2)
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if not preact:
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stem['norm'] = norm_layer(out_chs)
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if 'fixed' in stem_type:
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# 'fixed' SAME padding approximation that is used in BiT models
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stem['pad'] = nn.ConstantPad2d(1, 0.)
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stem['pool'] = nn.MaxPool2d(kernel_size=3, stride=2, padding=0)
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elif 'same' in stem_type:
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# full, input size based 'SAME' padding, used in ViT Hybrid model
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stem['pool'] = create_pool2d('max', kernel_size=3, stride=2, padding='same')
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else:
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# the usual PyTorch symmetric padding
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stem['pool'] = nn.MaxPool2d(kernel_size=3, stride=2, padding=1)
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return nn.Sequential(stem)
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class ResNetV2(nn.Module):
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"""Implementation of Pre-activation (v2) ResNet mode.
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"""
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def __init__(
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self,
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layers,
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channels=(256, 512, 1024, 2048),
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num_classes=1000,
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in_chans=3,
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|
global_pool='avg',
|
|
output_stride=32,
|
|
width_factor=1,
|
|
stem_chs=64,
|
|
stem_type='',
|
|
avg_down=False,
|
|
preact=True,
|
|
act_layer=nn.ReLU,
|
|
conv_layer=StdConv2d,
|
|
norm_layer=partial(GroupNormAct, num_groups=32),
|
|
drop_rate=0.,
|
|
drop_path_rate=0.,
|
|
zero_init_last=False,
|
|
):
|
|
super().__init__()
|
|
self.num_classes = num_classes
|
|
self.drop_rate = drop_rate
|
|
wf = width_factor
|
|
|
|
self.feature_info = []
|
|
stem_chs = make_div(stem_chs * wf)
|
|
self.stem = create_resnetv2_stem(
|
|
in_chans, stem_chs, stem_type, preact, conv_layer=conv_layer, norm_layer=norm_layer)
|
|
stem_feat = ('stem.conv3' if is_stem_deep(stem_type) else 'stem.conv') if preact else 'stem.norm'
|
|
self.feature_info.append(dict(num_chs=stem_chs, reduction=2, module=stem_feat))
|
|
|
|
prev_chs = stem_chs
|
|
curr_stride = 4
|
|
dilation = 1
|
|
block_dprs = [x.tolist() for x in torch.linspace(0, drop_path_rate, sum(layers)).split(layers)]
|
|
block_fn = PreActBottleneck if preact else Bottleneck
|
|
self.stages = nn.Sequential()
|
|
for stage_idx, (d, c, bdpr) in enumerate(zip(layers, channels, block_dprs)):
|
|
out_chs = make_div(c * wf)
|
|
stride = 1 if stage_idx == 0 else 2
|
|
if curr_stride >= output_stride:
|
|
dilation *= stride
|
|
stride = 1
|
|
stage = ResNetStage(
|
|
prev_chs,
|
|
out_chs,
|
|
stride=stride,
|
|
dilation=dilation,
|
|
depth=d,
|
|
avg_down=avg_down,
|
|
act_layer=act_layer,
|
|
conv_layer=conv_layer,
|
|
norm_layer=norm_layer,
|
|
block_dpr=bdpr,
|
|
block_fn=block_fn,
|
|
)
|
|
prev_chs = out_chs
|
|
curr_stride *= stride
|
|
self.feature_info += [dict(num_chs=prev_chs, reduction=curr_stride, module=f'stages.{stage_idx}')]
|
|
self.stages.add_module(str(stage_idx), stage)
|
|
|
|
self.num_features = prev_chs
|
|
self.norm = norm_layer(self.num_features) if preact else nn.Identity()
|
|
self.head = ClassifierHead(
|
|
self.num_features, num_classes, pool_type=global_pool, drop_rate=self.drop_rate, use_conv=True)
|
|
|
|
self.init_weights(zero_init_last=zero_init_last)
|
|
self.grad_checkpointing = False
|
|
|
|
@torch.jit.ignore
|
|
def init_weights(self, zero_init_last=True):
|
|
named_apply(partial(_init_weights, zero_init_last=zero_init_last), self)
|
|
|
|
@torch.jit.ignore()
|
|
def load_pretrained(self, checkpoint_path, prefix='resnet/'):
|
|
_load_weights(self, checkpoint_path, prefix)
|
|
|
|
@torch.jit.ignore
|
|
def group_matcher(self, coarse=False):
|
|
matcher = dict(
|
|
stem=r'^stem',
|
|
blocks=r'^stages\.(\d+)' if coarse else [
|
|
(r'^stages\.(\d+)\.blocks\.(\d+)', None),
|
|
(r'^norm', (99999,))
|
|
]
|
|
)
|
|
return matcher
|
|
|
|
@torch.jit.ignore
|
|
def set_grad_checkpointing(self, enable=True):
|
|
self.grad_checkpointing = enable
|
|
|
|
@torch.jit.ignore
|
|
def get_classifier(self):
|
|
return self.head.fc
|
|
|
|
def reset_classifier(self, num_classes, global_pool='avg'):
|
|
self.num_classes = num_classes
|
|
self.head = ClassifierHead(
|
|
self.num_features, num_classes, pool_type=global_pool, drop_rate=self.drop_rate, use_conv=True)
|
|
|
|
def forward_features(self, x):
|
|
x = self.stem(x)
|
|
if self.grad_checkpointing and not torch.jit.is_scripting():
|
|
x = checkpoint_seq(self.stages, x, flatten=True)
|
|
else:
|
|
x = self.stages(x)
|
|
x = self.norm(x)
|
|
return x
|
|
|
|
def forward_head(self, x, pre_logits: bool = False):
|
|
return self.head(x, pre_logits=pre_logits)
|
|
|
|
def forward(self, x):
|
|
x = self.forward_features(x)
|
|
x = self.forward_head(x)
|
|
return x
|
|
|
|
|
|
def _init_weights(module: nn.Module, name: str = '', zero_init_last=True):
|
|
if isinstance(module, nn.Linear) or ('head.fc' in name and isinstance(module, nn.Conv2d)):
|
|
nn.init.normal_(module.weight, mean=0.0, std=0.01)
|
|
nn.init.zeros_(module.bias)
|
|
elif isinstance(module, nn.Conv2d):
|
|
nn.init.kaiming_normal_(module.weight, mode='fan_out', nonlinearity='relu')
|
|
if module.bias is not None:
|
|
nn.init.zeros_(module.bias)
|
|
elif isinstance(module, (nn.BatchNorm2d, nn.LayerNorm, nn.GroupNorm)):
|
|
nn.init.ones_(module.weight)
|
|
nn.init.zeros_(module.bias)
|
|
elif zero_init_last and hasattr(module, 'zero_init_last'):
|
|
module.zero_init_last()
|
|
|
|
|
|
@torch.no_grad()
|
|
def _load_weights(model: nn.Module, checkpoint_path: str, prefix: str = 'resnet/'):
|
|
import numpy as np
|
|
|
|
def t2p(conv_weights):
|
|
"""Possibly convert HWIO to OIHW."""
|
|
if conv_weights.ndim == 4:
|
|
conv_weights = conv_weights.transpose([3, 2, 0, 1])
|
|
return torch.from_numpy(conv_weights)
|
|
|
|
weights = np.load(checkpoint_path)
|
|
stem_conv_w = adapt_input_conv(
|
|
model.stem.conv.weight.shape[1], t2p(weights[f'{prefix}root_block/standardized_conv2d/kernel']))
|
|
model.stem.conv.weight.copy_(stem_conv_w)
|
|
model.norm.weight.copy_(t2p(weights[f'{prefix}group_norm/gamma']))
|
|
model.norm.bias.copy_(t2p(weights[f'{prefix}group_norm/beta']))
|
|
if isinstance(getattr(model.head, 'fc', None), nn.Conv2d) and \
|
|
model.head.fc.weight.shape[0] == weights[f'{prefix}head/conv2d/kernel'].shape[-1]:
|
|
model.head.fc.weight.copy_(t2p(weights[f'{prefix}head/conv2d/kernel']))
|
|
model.head.fc.bias.copy_(t2p(weights[f'{prefix}head/conv2d/bias']))
|
|
for i, (sname, stage) in enumerate(model.stages.named_children()):
|
|
for j, (bname, block) in enumerate(stage.blocks.named_children()):
|
|
cname = 'standardized_conv2d'
|
|
block_prefix = f'{prefix}block{i + 1}/unit{j + 1:02d}/'
|
|
block.conv1.weight.copy_(t2p(weights[f'{block_prefix}a/{cname}/kernel']))
|
|
block.conv2.weight.copy_(t2p(weights[f'{block_prefix}b/{cname}/kernel']))
|
|
block.conv3.weight.copy_(t2p(weights[f'{block_prefix}c/{cname}/kernel']))
|
|
block.norm1.weight.copy_(t2p(weights[f'{block_prefix}a/group_norm/gamma']))
|
|
block.norm2.weight.copy_(t2p(weights[f'{block_prefix}b/group_norm/gamma']))
|
|
block.norm3.weight.copy_(t2p(weights[f'{block_prefix}c/group_norm/gamma']))
|
|
block.norm1.bias.copy_(t2p(weights[f'{block_prefix}a/group_norm/beta']))
|
|
block.norm2.bias.copy_(t2p(weights[f'{block_prefix}b/group_norm/beta']))
|
|
block.norm3.bias.copy_(t2p(weights[f'{block_prefix}c/group_norm/beta']))
|
|
if block.downsample is not None:
|
|
w = weights[f'{block_prefix}a/proj/{cname}/kernel']
|
|
block.downsample.conv.weight.copy_(t2p(w))
|
|
|
|
|
|
def _create_resnetv2(variant, pretrained=False, **kwargs):
|
|
feature_cfg = dict(flatten_sequential=True)
|
|
return build_model_with_cfg(
|
|
ResNetV2, variant, pretrained,
|
|
feature_cfg=feature_cfg,
|
|
**kwargs,
|
|
)
|
|
|
|
|
|
def _create_resnetv2_bit(variant, pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
variant, pretrained=pretrained, stem_type='fixed', conv_layer=partial(StdConv2d, eps=1e-8), **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50x1_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_50x1_bitm', pretrained=pretrained, layers=[3, 4, 6, 3], width_factor=1, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50x3_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_50x3_bitm', pretrained=pretrained, layers=[3, 4, 6, 3], width_factor=3, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101x1_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_101x1_bitm', pretrained=pretrained, layers=[3, 4, 23, 3], width_factor=1, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101x3_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_101x3_bitm', pretrained=pretrained, layers=[3, 4, 23, 3], width_factor=3, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x2_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x2_bitm', pretrained=pretrained, layers=[3, 8, 36, 3], width_factor=2, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x4_bitm(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x4_bitm', pretrained=pretrained, layers=[3, 8, 36, 3], width_factor=4, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50x1_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_50x1_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 4, 6, 3], width_factor=1, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50x3_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_50x3_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 4, 6, 3], width_factor=3, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101x1_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_101x1_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 4, 23, 3], width_factor=1, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101x3_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_101x3_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 4, 23, 3], width_factor=3, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x2_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x2_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 8, 36, 3], width_factor=2, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x4_bitm_in21k(pretrained=False, **kwargs):
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x4_bitm_in21k', pretrained=pretrained, num_classes=kwargs.pop('num_classes', 21843),
|
|
layers=[3, 8, 36, 3], width_factor=4, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50x1_bit_distilled(pretrained=False, **kwargs):
|
|
""" ResNetV2-50x1-BiT Distilled
|
|
Paper: Knowledge distillation: A good teacher is patient and consistent - https://arxiv.org/abs/2106.05237
|
|
"""
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_50x1_bit_distilled', pretrained=pretrained, layers=[3, 4, 6, 3], width_factor=1, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x2_bit_teacher(pretrained=False, **kwargs):
|
|
""" ResNetV2-152x2-BiT Teacher
|
|
Paper: Knowledge distillation: A good teacher is patient and consistent - https://arxiv.org/abs/2106.05237
|
|
"""
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x2_bit_teacher', pretrained=pretrained, layers=[3, 8, 36, 3], width_factor=2, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152x2_bit_teacher_384(pretrained=False, **kwargs):
|
|
""" ResNetV2-152xx-BiT Teacher @ 384x384
|
|
Paper: Knowledge distillation: A good teacher is patient and consistent - https://arxiv.org/abs/2106.05237
|
|
"""
|
|
return _create_resnetv2_bit(
|
|
'resnetv2_152x2_bit_teacher_384', pretrained=pretrained, layers=[3, 8, 36, 3], width_factor=2, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50d(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50d', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d,
|
|
stem_type='deep', avg_down=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50t(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50t', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d,
|
|
stem_type='tiered', avg_down=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_101', pretrained=pretrained,
|
|
layers=[3, 4, 23, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_101d(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_101d', pretrained=pretrained,
|
|
layers=[3, 4, 23, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d,
|
|
stem_type='deep', avg_down=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_152', pretrained=pretrained,
|
|
layers=[3, 8, 36, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_152d(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_152d', pretrained=pretrained,
|
|
layers=[3, 8, 36, 3], conv_layer=create_conv2d, norm_layer=BatchNormAct2d,
|
|
stem_type='deep', avg_down=True, **kwargs)
|
|
|
|
|
|
# Experimental configs (may change / be removed)
|
|
|
|
@register_model
|
|
def resnetv2_50d_gn(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50d_gn', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=GroupNormAct,
|
|
stem_type='deep', avg_down=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50d_evob(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50d_evob', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=EvoNorm2dB0,
|
|
stem_type='deep', avg_down=True, zero_init_last=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50d_evos(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50d_evos', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=EvoNorm2dS0,
|
|
stem_type='deep', avg_down=True, **kwargs)
|
|
|
|
|
|
@register_model
|
|
def resnetv2_50d_frn(pretrained=False, **kwargs):
|
|
return _create_resnetv2(
|
|
'resnetv2_50d_frn', pretrained=pretrained,
|
|
layers=[3, 4, 6, 3], conv_layer=create_conv2d, norm_layer=FilterResponseNormTlu2d,
|
|
stem_type='deep', avg_down=True, **kwargs)
|