mindspore2022/mindspore/model_zoo/vgg.py

105 lines
3.6 KiB
Python

# Copyright 2020 Huawei Technologies Co., Ltd
#
# 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.
# ============================================================================
"""VGG."""
import mindspore.nn as nn
from mindspore.common.initializer import initializer
import mindspore.common.dtype as mstype
def _make_layer(base, batch_norm):
"""Make stage network of VGG."""
layers = []
in_channels = 3
for v in base:
if v == 'M':
layers += [nn.MaxPool2d(kernel_size=2, stride=2)]
else:
weight_shape = (v, in_channels, 3, 3)
weight = initializer('XavierUniform', shape=weight_shape, dtype=mstype.float32).to_tensor()
conv2d = nn.Conv2d(in_channels=in_channels,
out_channels=v,
kernel_size=3,
padding=0,
pad_mode='same',
weight_init=weight)
if batch_norm:
layers += [conv2d, nn.BatchNorm2d(v), nn.ReLU()]
else:
layers += [conv2d, nn.ReLU()]
in_channels = v
return nn.SequentialCell(layers)
class Vgg(nn.Cell):
"""
VGG network definition.
Args:
base (list): Configuration for different layers, mainly the channel number of Conv layer.
num_classes (int): Class numbers. Default: 1000.
batch_norm (bool): Whether to do the batchnorm. Default: False.
batch_size (int): Batch size. Default: 1.
Returns:
Tensor, infer output tensor.
Examples:
>>> Vgg([64, 64, 'M', 128, 128, 'M', 256, 256, 256, 'M', 512, 512, 512, 'M', 512, 512, 512, 'M'],
>>> num_classes=1000, batch_norm=False, batch_size=1)
"""
def __init__(self, base, num_classes=1000, batch_norm=False, batch_size=1):
super(Vgg, self).__init__()
_ = batch_size
self.layers = _make_layer(base, batch_norm=batch_norm)
self.flatten = nn.Flatten()
self.classifier = nn.SequentialCell([
nn.Dense(512 * 7 * 7, 4096),
nn.ReLU(),
nn.Dense(4096, 4096),
nn.ReLU(),
nn.Dense(4096, num_classes)])
def construct(self, x):
x = self.layers(x)
x = self.flatten(x)
x = self.classifier(x)
return x
cfg = {
'11': [64, 'M', 128, 'M', 256, 256, 'M', 512, 512, 'M', 512, 512, 'M'],
'13': [64, 64, 'M', 128, 128, 'M', 256, 256, 'M', 512, 512, 'M', 512, 512, 'M'],
'16': [64, 64, 'M', 128, 128, 'M', 256, 256, 256, 'M', 512, 512, 512, 'M', 512, 512, 512, 'M'],
'19': [64, 64, 'M', 128, 128, 'M', 256, 256, 256, 256, 'M', 512, 512, 512, 512, 'M', 512, 512, 512, 512, 'M'],
}
def vgg16(num_classes=1000):
"""
Get Vgg16 neural network with batch normalization.
Args:
num_classes (int): Class numbers. Default: 1000.
Returns:
Cell, cell instance of Vgg16 neural network with batch normalization.
Examples:
>>> vgg16(num_classes=1000)
"""
net = Vgg(cfg['16'], num_classes=num_classes, batch_norm=True)
return net