PaddleClas/ppcls/modeling/architectures/densenet.py

205 lines
6.7 KiB
Python

#copyright (c) 2020 PaddlePaddle Authors. All Rights Reserve.
#
#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 math
import paddle
import paddle.fluid as fluid
from paddle.fluid.param_attr import ParamAttr
__all__ = [
"DenseNet", "DenseNet121", "DenseNet161", "DenseNet169", "DenseNet201",
"DenseNet264"
]
class DenseNet():
def __init__(self, layers=121):
self.layers = layers
def net(self, input, bn_size=4, dropout=0, class_dim=1000):
layers = self.layers
supported_layers = [121, 161, 169, 201, 264]
assert layers in supported_layers, \
"supported layers are {} but input layer is {}".format(supported_layers, layers)
densenet_spec = {
121: (64, 32, [6, 12, 24, 16]),
161: (96, 48, [6, 12, 36, 24]),
169: (64, 32, [6, 12, 32, 32]),
201: (64, 32, [6, 12, 48, 32]),
264: (64, 32, [6, 12, 64, 48])
}
num_init_features, growth_rate, block_config = densenet_spec[layers]
conv = fluid.layers.conv2d(
input=input,
num_filters=num_init_features,
filter_size=7,
stride=2,
padding=3,
act=None,
param_attr=ParamAttr(name="conv1_weights"),
bias_attr=False)
conv = fluid.layers.batch_norm(
input=conv,
act='relu',
param_attr=ParamAttr(name='conv1_bn_scale'),
bias_attr=ParamAttr(name='conv1_bn_offset'),
moving_mean_name='conv1_bn_mean',
moving_variance_name='conv1_bn_variance')
conv = fluid.layers.pool2d(
input=conv,
pool_size=3,
pool_stride=2,
pool_padding=1,
pool_type='max')
num_features = num_init_features
for i, num_layers in enumerate(block_config):
conv = self.make_dense_block(
conv,
num_layers,
bn_size,
growth_rate,
dropout,
name='conv' + str(i + 2))
num_features = num_features + num_layers * growth_rate
if i != len(block_config) - 1:
conv = self.make_transition(
conv, num_features // 2, name='conv' + str(i + 2) + '_blk')
num_features = num_features // 2
conv = fluid.layers.batch_norm(
input=conv,
act='relu',
param_attr=ParamAttr(name='conv5_blk_bn_scale'),
bias_attr=ParamAttr(name='conv5_blk_bn_offset'),
moving_mean_name='conv5_blk_bn_mean',
moving_variance_name='conv5_blk_bn_variance')
conv = fluid.layers.pool2d(
input=conv, pool_type='avg', global_pooling=True)
stdv = 1.0 / math.sqrt(conv.shape[1] * 1.0)
out = fluid.layers.fc(
input=conv,
size=class_dim,
param_attr=fluid.param_attr.ParamAttr(
initializer=fluid.initializer.Uniform(-stdv, stdv),
name="fc_weights"),
bias_attr=ParamAttr(name='fc_offset'))
return out
def make_transition(self, input, num_output_features, name=None):
bn_ac = fluid.layers.batch_norm(
input,
act='relu',
param_attr=ParamAttr(name=name + '_bn_scale'),
bias_attr=ParamAttr(name + '_bn_offset'),
moving_mean_name=name + '_bn_mean',
moving_variance_name=name + '_bn_variance')
bn_ac_conv = fluid.layers.conv2d(
input=bn_ac,
num_filters=num_output_features,
filter_size=1,
stride=1,
act=None,
bias_attr=False,
param_attr=ParamAttr(name=name + "_weights"))
pool = fluid.layers.pool2d(
input=bn_ac_conv, pool_size=2, pool_stride=2, pool_type='avg')
return pool
def make_dense_block(self,
input,
num_layers,
bn_size,
growth_rate,
dropout,
name=None):
conv = input
for layer in range(num_layers):
conv = self.make_dense_layer(
conv,
growth_rate,
bn_size,
dropout,
name=name + '_' + str(layer + 1))
return conv
def make_dense_layer(self, input, growth_rate, bn_size, dropout,
name=None):
bn_ac = fluid.layers.batch_norm(
input,
act='relu',
param_attr=ParamAttr(name=name + '_x1_bn_scale'),
bias_attr=ParamAttr(name + '_x1_bn_offset'),
moving_mean_name=name + '_x1_bn_mean',
moving_variance_name=name + '_x1_bn_variance')
bn_ac_conv = fluid.layers.conv2d(
input=bn_ac,
num_filters=bn_size * growth_rate,
filter_size=1,
stride=1,
act=None,
bias_attr=False,
param_attr=ParamAttr(name=name + "_x1_weights"))
bn_ac = fluid.layers.batch_norm(
bn_ac_conv,
act='relu',
param_attr=ParamAttr(name=name + '_x2_bn_scale'),
bias_attr=ParamAttr(name + '_x2_bn_offset'),
moving_mean_name=name + '_x2_bn_mean',
moving_variance_name=name + '_x2_bn_variance')
bn_ac_conv = fluid.layers.conv2d(
input=bn_ac,
num_filters=growth_rate,
filter_size=3,
stride=1,
padding=1,
act=None,
bias_attr=False,
param_attr=ParamAttr(name=name + "_x2_weights"))
if dropout:
bn_ac_conv = fluid.layers.dropout(
x=bn_ac_conv, dropout_prob=dropout)
bn_ac_conv = fluid.layers.concat([input, bn_ac_conv], axis=1)
return bn_ac_conv
def DenseNet121():
model = DenseNet(layers=121)
return model
def DenseNet161():
model = DenseNet(layers=161)
return model
def DenseNet169():
model = DenseNet(layers=169)
return model
def DenseNet201():
model = DenseNet(layers=201)
return model
def DenseNet264():
model = DenseNet(layers=264)
return model