PulseFocusPlatform/static/ppdet/modeling/backbones/acfpn.py

339 lines
12 KiB
Python

# Copyright (c) 2019 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
from collections import OrderedDict
import copy
from paddle import fluid
from paddle.fluid.param_attr import ParamAttr
from paddle.fluid.initializer import Xavier
from paddle.fluid.regularizer import L2Decay
from ppdet.core.workspace import register
from ppdet.modeling.ops import ConvNorm
__all__ = ['ACFPN']
@register
class ACFPN(object):
"""
Attention-guided Context Feature Pyramid Network for Object Detection,
see https://arxiv.org/abs/2005.11475
Args:
num_chan (int): number of feature channels
min_level (int): lowest level of the backbone feature map to use
max_level (int): highest level of the backbone feature map to use
spatial_scale (list): feature map scaling factor
has_extra_convs (bool): whether has extral convolutions in higher levels
norm_type (str|None): normalization type, 'bn'/'sync_bn'/'affine_channel'
use_c5 (bool): whether to use C5 as the feature map.
norm_groups (int): group number of group norm.
"""
__shared__ = ['norm_type', 'freeze_norm']
def __init__(self,
num_chan=256,
min_level=2,
max_level=6,
spatial_scale=[1. / 32., 1. / 16., 1. / 8., 1. / 4.],
has_extra_convs=False,
norm_type=None,
freeze_norm=False,
use_c5=True,
norm_groups=32):
self.freeze_norm = freeze_norm
self.num_chan = num_chan
self.min_level = min_level
self.max_level = max_level
self.spatial_scale = spatial_scale
self.has_extra_convs = has_extra_convs
self.norm_type = norm_type
self.use_c5 = use_c5
self.norm_groups = norm_groups
def _add_topdown_lateral(self, body_name, body_input, upper_output):
lateral_name = 'fpn_inner_' + body_name + '_lateral'
topdown_name = 'fpn_topdown_' + body_name
fan = body_input.shape[1]
if self.norm_type:
initializer = Xavier(fan_out=fan)
lateral = ConvNorm(
body_input,
self.num_chan,
1,
initializer=initializer,
norm_type=self.norm_type,
freeze_norm=self.freeze_norm,
name=lateral_name,
norm_name=lateral_name)
else:
lateral = fluid.layers.conv2d(
body_input,
self.num_chan,
1,
param_attr=ParamAttr(
name=lateral_name + "_w", initializer=Xavier(fan_out=fan)),
bias_attr=ParamAttr(
name=lateral_name + "_b",
learning_rate=2.,
regularizer=L2Decay(0.)),
name=lateral_name)
topdown = fluid.layers.resize_nearest(
upper_output, scale=2., name=topdown_name)
return lateral + topdown
def dense_aspp_block(self, input, num_filters1, num_filters2, dilation_rate,
dropout_prob, name):
conv = ConvNorm(
input,
num_filters=num_filters1,
filter_size=1,
stride=1,
groups=1,
norm_decay=0.,
norm_type='gn',
norm_groups=self.norm_groups,
dilation=dilation_rate,
lr_scale=1,
freeze_norm=False,
act="relu",
norm_name=name + "_gn",
initializer=None,
bias_attr=False,
name=name + "_gn")
conv = fluid.layers.conv2d(
conv,
num_filters2,
filter_size=3,
padding=dilation_rate,
dilation=dilation_rate,
act="relu",
param_attr=ParamAttr(name=name + "_conv_w"),
bias_attr=ParamAttr(name=name + "_conv_b"), )
if dropout_prob > 0:
conv = fluid.layers.dropout(conv, dropout_prob=dropout_prob)
return conv
def dense_aspp(self, input, name=None):
dropout0 = 0.1
d_feature0 = 512
d_feature1 = 256
aspp3 = self.dense_aspp_block(
input,
num_filters1=d_feature0,
num_filters2=d_feature1,
dropout_prob=dropout0,
name=name + '_aspp3',
dilation_rate=3)
conv = fluid.layers.concat([aspp3, input], axis=1)
aspp6 = self.dense_aspp_block(
conv,
num_filters1=d_feature0,
num_filters2=d_feature1,
dropout_prob=dropout0,
name=name + '_aspp6',
dilation_rate=6)
conv = fluid.layers.concat([aspp6, conv], axis=1)
aspp12 = self.dense_aspp_block(
conv,
num_filters1=d_feature0,
num_filters2=d_feature1,
dropout_prob=dropout0,
name=name + '_aspp12',
dilation_rate=12)
conv = fluid.layers.concat([aspp12, conv], axis=1)
aspp18 = self.dense_aspp_block(
conv,
num_filters1=d_feature0,
num_filters2=d_feature1,
dropout_prob=dropout0,
name=name + '_aspp18',
dilation_rate=18)
conv = fluid.layers.concat([aspp18, conv], axis=1)
aspp24 = self.dense_aspp_block(
conv,
num_filters1=d_feature0,
num_filters2=d_feature1,
dropout_prob=dropout0,
name=name + '_aspp24',
dilation_rate=24)
conv = fluid.layers.concat(
[aspp3, aspp6, aspp12, aspp18, aspp24], axis=1)
conv = ConvNorm(
conv,
num_filters=self.num_chan,
filter_size=1,
stride=1,
groups=1,
norm_decay=0.,
norm_type='gn',
norm_groups=self.norm_groups,
dilation=1,
lr_scale=1,
freeze_norm=False,
act="relu",
norm_name=name + "_dense_aspp_reduce_gn",
initializer=None,
bias_attr=False,
name=name + "_dense_aspp_reduce_gn")
return conv
def get_output(self, body_dict):
"""
Add FPN onto backbone.
Args:
body_dict(OrderedDict): Dictionary of variables and each element is the
output of backbone.
Return:
fpn_dict(OrderedDict): A dictionary represents the output of FPN with
their name.
spatial_scale(list): A list of multiplicative spatial scale factor.
"""
spatial_scale = copy.deepcopy(self.spatial_scale)
body_name_list = list(body_dict.keys())[::-1]
num_backbone_stages = len(body_name_list)
self.fpn_inner_output = [[] for _ in range(num_backbone_stages)]
fpn_inner_name = 'fpn_inner_' + body_name_list[0]
body_input = body_dict[body_name_list[0]]
fan = body_input.shape[1]
if self.norm_type:
initializer = Xavier(fan_out=fan)
self.fpn_inner_output[0] = ConvNorm(
body_input,
self.num_chan,
1,
initializer=initializer,
norm_type=self.norm_type,
freeze_norm=self.freeze_norm,
name=fpn_inner_name,
norm_name=fpn_inner_name)
else:
self.fpn_inner_output[0] = fluid.layers.conv2d(
body_input,
self.num_chan,
1,
param_attr=ParamAttr(
name=fpn_inner_name + "_w",
initializer=Xavier(fan_out=fan)),
bias_attr=ParamAttr(
name=fpn_inner_name + "_b",
learning_rate=2.,
regularizer=L2Decay(0.)),
name=fpn_inner_name)
self.fpn_inner_output[0] += self.dense_aspp(
self.fpn_inner_output[0], name="acfpn")
for i in range(1, num_backbone_stages):
body_name = body_name_list[i]
body_input = body_dict[body_name]
top_output = self.fpn_inner_output[i - 1]
fpn_inner_single = self._add_topdown_lateral(body_name, body_input,
top_output)
self.fpn_inner_output[i] = fpn_inner_single
fpn_dict = {}
fpn_name_list = []
for i in range(num_backbone_stages):
fpn_name = 'fpn_' + body_name_list[i]
fan = self.fpn_inner_output[i].shape[1] * 3 * 3
if self.norm_type:
initializer = Xavier(fan_out=fan)
fpn_output = ConvNorm(
self.fpn_inner_output[i],
self.num_chan,
3,
initializer=initializer,
norm_type=self.norm_type,
freeze_norm=self.freeze_norm,
name=fpn_name,
norm_name=fpn_name)
else:
fpn_output = fluid.layers.conv2d(
self.fpn_inner_output[i],
self.num_chan,
filter_size=3,
padding=1,
param_attr=ParamAttr(
name=fpn_name + "_w", initializer=Xavier(fan_out=fan)),
bias_attr=ParamAttr(
name=fpn_name + "_b",
learning_rate=2.,
regularizer=L2Decay(0.)),
name=fpn_name)
fpn_dict[fpn_name] = fpn_output
fpn_name_list.append(fpn_name)
if not self.has_extra_convs and self.max_level - self.min_level == len(
spatial_scale):
body_top_name = fpn_name_list[0]
body_top_extension = fluid.layers.pool2d(
fpn_dict[body_top_name],
1,
'max',
pool_stride=2,
name=body_top_name + '_subsampled_2x')
fpn_dict[body_top_name + '_subsampled_2x'] = body_top_extension
fpn_name_list.insert(0, body_top_name + '_subsampled_2x')
spatial_scale.insert(0, spatial_scale[0] * 0.5)
# Coarser FPN levels introduced for RetinaNet
highest_backbone_level = self.min_level + len(spatial_scale) - 1
if self.has_extra_convs and self.max_level > highest_backbone_level:
if self.use_c5:
fpn_blob = body_dict[body_name_list[0]]
else:
fpn_blob = fpn_dict[fpn_name_list[0]]
for i in range(highest_backbone_level + 1, self.max_level + 1):
fpn_blob_in = fpn_blob
fpn_name = 'fpn_' + str(i)
if i > highest_backbone_level + 1:
fpn_blob_in = fluid.layers.relu(fpn_blob)
fan = fpn_blob_in.shape[1] * 3 * 3
fpn_blob = fluid.layers.conv2d(
input=fpn_blob_in,
num_filters=self.num_chan,
filter_size=3,
stride=2,
padding=1,
param_attr=ParamAttr(
name=fpn_name + "_w", initializer=Xavier(fan_out=fan)),
bias_attr=ParamAttr(
name=fpn_name + "_b",
learning_rate=2.,
regularizer=L2Decay(0.)),
name=fpn_name)
fpn_dict[fpn_name] = fpn_blob
fpn_name_list.insert(0, fpn_name)
spatial_scale.insert(0, spatial_scale[0] * 0.5)
res_dict = OrderedDict([(k, fpn_dict[k]) for k in fpn_name_list])
return res_dict, spatial_scale