PulseFocusPlatform/static/ppdet/modeling/architectures/retinanet.py

132 lines
4.7 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 paddle.fluid as fluid
from ppdet.experimental import mixed_precision_global_state
from ppdet.core.workspace import register
__all__ = ['RetinaNet']
@register
class RetinaNet(object):
"""
RetinaNet architecture, see https://arxiv.org/abs/1708.02002
Args:
backbone (object): backbone instance
fpn (object): feature pyramid network instance
retina_head (object): `RetinaHead` instance
"""
__category__ = 'architecture'
__inject__ = ['backbone', 'fpn', 'retina_head']
def __init__(self, backbone, fpn, retina_head):
super(RetinaNet, self).__init__()
self.backbone = backbone
self.fpn = fpn
self.retina_head = retina_head
def build(self, feed_vars, mode='train'):
im = feed_vars['image']
im_info = feed_vars['im_info']
if mode == 'train':
gt_bbox = feed_vars['gt_bbox']
gt_class = feed_vars['gt_class']
is_crowd = feed_vars['is_crowd']
mixed_precision_enabled = mixed_precision_global_state() is not None
# cast inputs to FP16
if mixed_precision_enabled:
im = fluid.layers.cast(im, 'float16')
# backbone
body_feats = self.backbone(im)
# cast features back to FP32
if mixed_precision_enabled:
body_feats = OrderedDict((k, fluid.layers.cast(v, 'float32'))
for k, v in body_feats.items())
# FPN
body_feats, spatial_scale = self.fpn.get_output(body_feats)
# retinanet head
if mode == 'train':
loss = self.retina_head.get_loss(body_feats, spatial_scale, im_info,
gt_bbox, gt_class, is_crowd)
total_loss = fluid.layers.sum(list(loss.values()))
loss.update({'loss': total_loss})
return loss
else:
pred = self.retina_head.get_prediction(body_feats, spatial_scale,
im_info)
return pred
def _inputs_def(self, image_shape):
im_shape = [None] + image_shape
# yapf: disable
inputs_def = {
'image': {'shape': im_shape, 'dtype': 'float32', 'lod_level': 0},
'im_info': {'shape': [None, 3], 'dtype': 'float32', 'lod_level': 0},
'im_id': {'shape': [None, 1], 'dtype': 'int64', 'lod_level': 0},
'im_shape': {'shape': [None, 3], 'dtype': 'float32', 'lod_level': 0},
'gt_bbox': {'shape': [None, 4], 'dtype': 'float32', 'lod_level': 1},
'gt_class': {'shape': [None, 1], 'dtype': 'int32', 'lod_level': 1},
'is_crowd': {'shape': [None, 1], 'dtype': 'int32', 'lod_level': 1},
'is_difficult': {'shape': [None, 1], 'dtype': 'int32', 'lod_level': 1},
}
# yapf: enable
return inputs_def
def build_inputs(
self,
image_shape=[3, None, None],
fields=[
'image', 'im_info', 'im_id', 'gt_bbox', 'gt_class', 'is_crowd'
], # for-train
use_dataloader=True,
iterable=False):
inputs_def = self._inputs_def(image_shape)
feed_vars = OrderedDict([(key, fluid.data(
name=key,
shape=inputs_def[key]['shape'],
dtype=inputs_def[key]['dtype'],
lod_level=inputs_def[key]['lod_level'])) for key in fields])
loader = fluid.io.DataLoader.from_generator(
feed_list=list(feed_vars.values()),
capacity=16,
use_double_buffer=True,
iterable=iterable) if use_dataloader else None
return feed_vars, loader
def train(self, feed_vars):
return self.build(feed_vars, 'train')
def eval(self, feed_vars):
return self.build(feed_vars, 'test')
def test(self, feed_vars, exclude_nms=False):
assert not exclude_nms, "exclude_nms for {} is not support currently".format(
self.__class__.__name__)
return self.build(feed_vars, 'test')