# copyright (c) 2021 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. import math import numpy as np import paddle from paddle import ParamAttr import paddle.nn as nn import paddle.nn.functional as F from paddle.nn import Conv2D, BatchNorm, Linear, Dropout from paddle.nn import AdaptiveAvgPool2D, MaxPool2D, AvgPool2D from paddleseg import utils from paddleseg.cvlibs import manager MODEL_URLS = { "MobileNetV2_x0_25": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_x0_25_pretrained.pdparams", "MobileNetV2_x0_5": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_x0_5_pretrained.pdparams", "MobileNetV2_x0_75": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_x0_75_pretrained.pdparams", "MobileNetV2": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_pretrained.pdparams", "MobileNetV2_x1_5": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_x1_5_pretrained.pdparams", "MobileNetV2_x2_0": "https://paddle-imagenet-models-name.bj.bcebos.com/dygraph/MobileNetV2_x2_0_pretrained.pdparams" } __all__ = ["MobileNetV2"] class ConvBNLayer(nn.Layer): def __init__(self, num_channels, filter_size, num_filters, stride, padding, channels=None, num_groups=1, name=None, use_cudnn=True): super(ConvBNLayer, self).__init__() self._conv = Conv2D( in_channels=num_channels, out_channels=num_filters, kernel_size=filter_size, stride=stride, padding=padding, groups=num_groups, weight_attr=ParamAttr(name=name + "_weights"), bias_attr=False) self._batch_norm = BatchNorm( num_filters, param_attr=ParamAttr(name=name + "_bn_scale"), bias_attr=ParamAttr(name=name + "_bn_offset"), moving_mean_name=name + "_bn_mean", moving_variance_name=name + "_bn_variance") def forward(self, inputs, if_act=True): y = self._conv(inputs) y = self._batch_norm(y) if if_act: y = F.relu6(y) return y class InvertedResidualUnit(nn.Layer): def __init__(self, num_channels, num_in_filter, num_filters, stride, filter_size, padding, expansion_factor, name): super(InvertedResidualUnit, self).__init__() num_expfilter = int(round(num_in_filter * expansion_factor)) self._expand_conv = ConvBNLayer( num_channels=num_channels, num_filters=num_expfilter, filter_size=1, stride=1, padding=0, num_groups=1, name=name + "_expand") self._bottleneck_conv = ConvBNLayer( num_channels=num_expfilter, num_filters=num_expfilter, filter_size=filter_size, stride=stride, padding=padding, num_groups=num_expfilter, use_cudnn=False, name=name + "_dwise") self._linear_conv = ConvBNLayer( num_channels=num_expfilter, num_filters=num_filters, filter_size=1, stride=1, padding=0, num_groups=1, name=name + "_linear") def forward(self, inputs, ifshortcut): y = self._expand_conv(inputs, if_act=True) y = self._bottleneck_conv(y, if_act=True) y = self._linear_conv(y, if_act=False) if ifshortcut: y = paddle.add(inputs, y) return y class InvresiBlocks(nn.Layer): def __init__(self, in_c, t, c, n, s, name): super(InvresiBlocks, self).__init__() self._first_block = InvertedResidualUnit( num_channels=in_c, num_in_filter=in_c, num_filters=c, stride=s, filter_size=3, padding=1, expansion_factor=t, name=name + "_1") self._block_list = [] for i in range(1, n): block = self.add_sublayer( name + "_" + str(i + 1), sublayer=InvertedResidualUnit( num_channels=c, num_in_filter=c, num_filters=c, stride=1, filter_size=3, padding=1, expansion_factor=t, name=name + "_" + str(i + 1))) self._block_list.append(block) def forward(self, inputs): y = self._first_block(inputs, ifshortcut=False) for block in self._block_list: y = block(y, ifshortcut=True) return y class MobileNet(nn.Layer): def __init__(self, input_channels=3, scale=1.0, pretrained=None, prefix_name=""): super(MobileNet, self).__init__() self.scale = scale bottleneck_params_list = [ (1, 16, 1, 1), (6, 24, 2, 2), (6, 32, 3, 2), (6, 64, 4, 2), (6, 96, 3, 1), (6, 160, 3, 2), (6, 320, 1, 1), ] self.conv1 = ConvBNLayer( num_channels=input_channels, num_filters=int(32 * scale), filter_size=3, stride=2, padding=1, name=prefix_name + "conv1_1") self.block_list = [] i = 1 in_c = int(32 * scale) for layer_setting in bottleneck_params_list: t, c, n, s = layer_setting i += 1 block = self.add_sublayer( prefix_name + "conv" + str(i), sublayer=InvresiBlocks( in_c=in_c, t=t, c=int(c * scale), n=n, s=s, name=prefix_name + "conv" + str(i))) self.block_list.append(block) in_c = int(c * scale) self.out_c = int(1280 * scale) if scale > 1.0 else 1280 self.conv9 = ConvBNLayer( num_channels=in_c, num_filters=self.out_c, filter_size=1, stride=1, padding=0, name=prefix_name + "conv9") self.feat_channels = [int(i * scale) for i in [16, 24, 32, 96, 1280]] self.pretrained = pretrained self.init_weight() def forward(self, inputs): feat_list = [] y = self.conv1(inputs, if_act=True) block_index = 0 for block in self.block_list: y = block(y) if block_index in [0, 1, 2, 4]: feat_list.append(y) block_index += 1 y = self.conv9(y, if_act=True) feat_list.append(y) return feat_list def init_weight(self): utils.load_pretrained_model(self, self.pretrained) @manager.BACKBONES.add_component def MobileNetV2(**kwargs): model = MobileNet(scale=1.0, **kwargs) return model