You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 

281 lines
8.6 KiB

# Copyright (c) 2022 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import paddle
import paddle.nn as nn
import paddle.nn.functional as F
from paddle.nn.initializer import Normal, Constant
from paddle import ParamAttr
from paddle.nn import AdaptiveAvgPool2D, BatchNorm2D, Conv2D, Linear
from paddle.regularizer import L2Decay
from paddle.nn.initializer import KaimingNormal, XavierNormal
from paddlers.models.ppdet.core.workspace import register
__all__ = ['PPLCNetEmbedding']
# Each element(list) represents a depthwise block, which is composed of k, in_c, out_c, s, use_se.
# k: kernel_size
# in_c: input channel number in depthwise block
# out_c: output channel number in depthwise block
# s: stride in depthwise block
# use_se: whether to use SE block
NET_CONFIG = {
"blocks2":
#k, in_c, out_c, s, use_se
[[3, 16, 32, 1, False]],
"blocks3": [[3, 32, 64, 2, False], [3, 64, 64, 1, False]],
"blocks4": [[3, 64, 128, 2, False], [3, 128, 128, 1, False]],
"blocks5":
[[3, 128, 256, 2, False], [5, 256, 256, 1, False], [5, 256, 256, 1, False],
[5, 256, 256, 1, False], [5, 256, 256, 1, False], [5, 256, 256, 1, False]],
"blocks6": [[5, 256, 512, 2, True], [5, 512, 512, 1, True]]
}
def make_divisible(v, divisor=8, min_value=None):
if min_value is None:
min_value = divisor
new_v = max(min_value, int(v + divisor / 2) // divisor * divisor)
if new_v < 0.9 * v:
new_v += divisor
return new_v
class ConvBNLayer(nn.Layer):
def __init__(self,
num_channels,
filter_size,
num_filters,
stride,
num_groups=1):
super().__init__()
self.conv = Conv2D(
in_channels=num_channels,
out_channels=num_filters,
kernel_size=filter_size,
stride=stride,
padding=(filter_size - 1) // 2,
groups=num_groups,
weight_attr=ParamAttr(initializer=KaimingNormal()),
bias_attr=False)
self.bn = BatchNorm2D(
num_filters,
weight_attr=ParamAttr(regularizer=L2Decay(0.0)),
bias_attr=ParamAttr(regularizer=L2Decay(0.0)))
self.hardswish = nn.Hardswish()
def forward(self, x):
x = self.conv(x)
x = self.bn(x)
x = self.hardswish(x)
return x
class DepthwiseSeparable(nn.Layer):
def __init__(self,
num_channels,
num_filters,
stride,
dw_size=3,
use_se=False):
super().__init__()
self.use_se = use_se
self.dw_conv = ConvBNLayer(
num_channels=num_channels,
num_filters=num_channels,
filter_size=dw_size,
stride=stride,
num_groups=num_channels)
if use_se:
self.se = SEModule(num_channels)
self.pw_conv = ConvBNLayer(
num_channels=num_channels,
filter_size=1,
num_filters=num_filters,
stride=1)
def forward(self, x):
x = self.dw_conv(x)
if self.use_se:
x = self.se(x)
x = self.pw_conv(x)
return x
class SEModule(nn.Layer):
def __init__(self, channel, reduction=4):
super().__init__()
self.avg_pool = AdaptiveAvgPool2D(1)
self.conv1 = Conv2D(
in_channels=channel,
out_channels=channel // reduction,
kernel_size=1,
stride=1,
padding=0)
self.relu = nn.ReLU()
self.conv2 = Conv2D(
in_channels=channel // reduction,
out_channels=channel,
kernel_size=1,
stride=1,
padding=0)
self.hardsigmoid = nn.Hardsigmoid()
def forward(self, x):
identity = x
x = self.avg_pool(x)
x = self.conv1(x)
x = self.relu(x)
x = self.conv2(x)
x = self.hardsigmoid(x)
x = paddle.multiply(x=identity, y=x)
return x
class PPLCNet(nn.Layer):
"""
PP-LCNet, see https://arxiv.org/abs/2109.15099.
This code is different from PPLCNet in ppdet/modeling/backbones/lcnet.py
or in PaddleClas, because the output is the flatten feature of last_conv.
Args:
scale (float): Scale ratio of channels.
class_expand (int): Number of channels of conv feature.
"""
def __init__(self, scale=1.0, class_expand=1280):
super(PPLCNet, self).__init__()
self.scale = scale
self.class_expand = class_expand
self.conv1 = ConvBNLayer(
num_channels=3,
filter_size=3,
num_filters=make_divisible(16 * scale),
stride=2)
self.blocks2 = nn.Sequential(*[
DepthwiseSeparable(
num_channels=make_divisible(in_c * scale),
num_filters=make_divisible(out_c * scale),
dw_size=k,
stride=s,
use_se=se)
for i, (k, in_c, out_c, s, se) in enumerate(NET_CONFIG["blocks2"])
])
self.blocks3 = nn.Sequential(*[
DepthwiseSeparable(
num_channels=make_divisible(in_c * scale),
num_filters=make_divisible(out_c * scale),
dw_size=k,
stride=s,
use_se=se)
for i, (k, in_c, out_c, s, se) in enumerate(NET_CONFIG["blocks3"])
])
self.blocks4 = nn.Sequential(*[
DepthwiseSeparable(
num_channels=make_divisible(in_c * scale),
num_filters=make_divisible(out_c * scale),
dw_size=k,
stride=s,
use_se=se)
for i, (k, in_c, out_c, s, se) in enumerate(NET_CONFIG["blocks4"])
])
self.blocks5 = nn.Sequential(*[
DepthwiseSeparable(
num_channels=make_divisible(in_c * scale),
num_filters=make_divisible(out_c * scale),
dw_size=k,
stride=s,
use_se=se)
for i, (k, in_c, out_c, s, se) in enumerate(NET_CONFIG["blocks5"])
])
self.blocks6 = nn.Sequential(*[
DepthwiseSeparable(
num_channels=make_divisible(in_c * scale),
num_filters=make_divisible(out_c * scale),
dw_size=k,
stride=s,
use_se=se)
for i, (k, in_c, out_c, s, se) in enumerate(NET_CONFIG["blocks6"])
])
self.avg_pool = AdaptiveAvgPool2D(1)
self.last_conv = Conv2D(
in_channels=make_divisible(NET_CONFIG["blocks6"][-1][2] * scale),
out_channels=self.class_expand,
kernel_size=1,
stride=1,
padding=0,
bias_attr=False)
self.hardswish = nn.Hardswish()
self.flatten = nn.Flatten(start_axis=1, stop_axis=-1)
def forward(self, x):
x = self.conv1(x)
x = self.blocks2(x)
x = self.blocks3(x)
x = self.blocks4(x)
x = self.blocks5(x)
x = self.blocks6(x)
x = self.avg_pool(x)
x = self.last_conv(x)
x = self.hardswish(x)
x = self.flatten(x)
return x
class FC(nn.Layer):
def __init__(self, input_ch, output_ch):
super(FC, self).__init__()
weight_attr = ParamAttr(initializer=XavierNormal())
self.fc = paddle.nn.Linear(input_ch, output_ch, weight_attr=weight_attr)
def forward(self, x):
out = self.fc(x)
return out
@register
class PPLCNetEmbedding(nn.Layer):
"""
PPLCNet Embedding
Args:
input_ch (int): Number of channels of input conv feature.
output_ch (int): Number of channels of output conv feature.
"""
def __init__(self, scale=2.5, input_ch=1280, output_ch=512):
super(PPLCNetEmbedding, self).__init__()
self.backbone = PPLCNet(scale=scale)
self.neck = FC(input_ch, output_ch)
def forward(self, x):
feat = self.backbone(x)
feat_out = self.neck(feat)
return feat_out