PulseFocusPlatform/ppdet/modeling/architectures/fcos.py

106 lines
3.5 KiB
Python

# Copyright (c) 2020 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
from ppdet.core.workspace import register, create
from .meta_arch import BaseArch
__all__ = ['FCOS']
@register
class FCOS(BaseArch):
"""
FCOS network, see https://arxiv.org/abs/1904.01355
Args:
backbone (object): backbone instance
neck (object): 'FPN' instance
fcos_head (object): 'FCOSHead' instance
post_process (object): 'FCOSPostProcess' instance
"""
__category__ = 'architecture'
__inject__ = ['fcos_post_process']
def __init__(self,
backbone,
neck,
fcos_head='FCOSHead',
fcos_post_process='FCOSPostProcess'):
super(FCOS, self).__init__()
self.backbone = backbone
self.neck = neck
self.fcos_head = fcos_head
self.fcos_post_process = fcos_post_process
@classmethod
def from_config(cls, cfg, *args, **kwargs):
backbone = create(cfg['backbone'])
kwargs = {'input_shape': backbone.out_shape}
neck = create(cfg['neck'], **kwargs)
kwargs = {'input_shape': neck.out_shape}
fcos_head = create(cfg['fcos_head'], **kwargs)
return {
'backbone': backbone,
'neck': neck,
"fcos_head": fcos_head,
}
def _forward(self):
body_feats = self.backbone(self.inputs)
fpn_feats = self.neck(body_feats)
fcos_head_outs = self.fcos_head(fpn_feats, self.training)
if not self.training:
scale_factor = self.inputs['scale_factor']
bboxes = self.fcos_post_process(fcos_head_outs, scale_factor)
return bboxes
else:
return fcos_head_outs
def get_loss(self, ):
loss = {}
tag_labels, tag_bboxes, tag_centerness = [], [], []
for i in range(len(self.fcos_head.fpn_stride)):
# labels, reg_target, centerness
k_lbl = 'labels{}'.format(i)
if k_lbl in self.inputs:
tag_labels.append(self.inputs[k_lbl])
k_box = 'reg_target{}'.format(i)
if k_box in self.inputs:
tag_bboxes.append(self.inputs[k_box])
k_ctn = 'centerness{}'.format(i)
if k_ctn in self.inputs:
tag_centerness.append(self.inputs[k_ctn])
fcos_head_outs = self._forward()
loss_fcos = self.fcos_head.get_loss(fcos_head_outs, tag_labels,
tag_bboxes, tag_centerness)
loss.update(loss_fcos)
total_loss = paddle.add_n(list(loss.values()))
loss.update({'loss': total_loss})
return loss
def get_pred(self):
bbox_pred, bbox_num = self._forward()
output = {'bbox': bbox_pred, 'bbox_num': bbox_num}
return output