Ma Zerun 65410b05ad
Fix Mobilenetv3 structure and add pretrained model (#291)
* Refactor Mobilenetv3 structure and add ConvClsHead.

* Change model's name from 'MobileNetv3' to 'MobileNetV3'

* Modify configs for MobileNetV3 on CIFAR10.

And add MobileNetV3 configs for imagenet

* Fix activate setting bugs in MobileNetV3.

And remove bias in SELayer.

* Modify unittest

* Remove useless config and file.

* Fix mobilenetv3-large arch setting

* Add dropout option in ConvClsHead

* Fix MobilenetV3 structure according to torchvision version.

1. Remove with_expand_conv option in InvertedResidual, it should be decided by channels.

2. Revert activation function, should before SE layer.

* Format code.

* Rename MobilenetV3 arch "big" to "large".

* Add mobilenetv3_small torchvision training recipe

* Modify default `out_indices` of MobilenetV3, now it will change
according to `arch` if not specified.

* Add MobilenetV3 large config.

* Add mobilenetv3 README

* Modify InvertedResidual unit test.

* Refactor ConvClsHead to StackedLinearClsHead, and add unit tests.

* Add unit test for `simple_test` of `StackedLinearClsHead`.

* Fix typo

Co-authored-by: Yidi Shao <ydshao@smail.nju.edu.cn>
2021-06-27 23:19:36 +08:00

63 lines
2.2 KiB
Python

import mmcv
import torch.nn as nn
from mmcv.cnn import ConvModule
from mmcv.runner import BaseModule
from .make_divisible import make_divisible
# class SELayer(nn.Module):
class SELayer(BaseModule):
"""Squeeze-and-Excitation Module.
Args:
channels (int): The input (and output) channels of the SE layer.
ratio (int): Squeeze ratio in SELayer, the intermediate channel will be
``int(channels/ratio)``. Default: 16.
conv_cfg (None or dict): Config dict for convolution layer.
Default: None, which means using conv2d.
act_cfg (dict or Sequence[dict]): Config dict for activation layer.
If act_cfg is a dict, two activation layers will be configurated
by this dict. If act_cfg is a sequence of dicts, the first
activation layer will be configurated by the first dict and the
second activation layer will be configurated by the second dict.
Default: (dict(type='ReLU'), dict(type='Sigmoid'))
"""
def __init__(self,
channels,
ratio=16,
bias='auto',
conv_cfg=None,
act_cfg=(dict(type='ReLU'), dict(type='Sigmoid')),
init_cfg=None):
super(SELayer, self).__init__(init_cfg)
if isinstance(act_cfg, dict):
act_cfg = (act_cfg, act_cfg)
assert len(act_cfg) == 2
assert mmcv.is_tuple_of(act_cfg, dict)
self.global_avgpool = nn.AdaptiveAvgPool2d(1)
squeeze_channels = make_divisible(channels // ratio, 8)
self.conv1 = ConvModule(
in_channels=channels,
out_channels=squeeze_channels,
kernel_size=1,
stride=1,
bias=bias,
conv_cfg=conv_cfg,
act_cfg=act_cfg[0])
self.conv2 = ConvModule(
in_channels=squeeze_channels,
out_channels=channels,
kernel_size=1,
stride=1,
bias=bias,
conv_cfg=conv_cfg,
act_cfg=act_cfg[1])
def forward(self, x):
out = self.global_avgpool(x)
out = self.conv1(out)
out = self.conv2(out)
return x * out