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# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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# http://www.apache.org/licenses/LICENSE-2.0
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# ============================================================================
"""LeNet5 backbone."""
import mindspore.nn as nn
from mindspore.common.initializer import Normal
from mindvision.engine.class_factory import ClassFactory, ModuleType
__all__ = ["LeNet5"]
[docs]@ClassFactory.register(ModuleType.BACKBONE)
class LeNet5(nn.Cell):
"""
LeNet backbone.
Args:
num_class (int): The number of classes. Default: 10.
num_channel (int): The number of channels. Default: 1.
include_top (bool): Whether to use the TOP architecture. Default: True.
Inputs:
- **x** (Tensor) - Tensor of shape :math:`(N, C_{in}, H_{in}, W_{in})`
Outputs:
Tensor of shape :math:`(N, 10)`
Supported Platforms:
``GPU``
Examples:
>>> import numpy as np
>>>
>>> import mindspore as ms
>>> from mindvision.classification.models.backbones import LeNet5
>>>
>>> net = LeNet5()
>>> x = ms.Tensor(np.ones([1, 1, 32, 32]), ms.float32)
>>> output = net(x)
>>> print(output.shape)
(1, 10)
About LeNet5:
LeNet5 trained with the back-propagation algorithm constitute the best example of
a successful gradient based learning technique. Given an appropriate network architecture,
gradient-based learning algorithms can be used to synthesize a complex decision surface
that can classify high-dimensional patterns, such as handwritten characters, with
minimal preprocessing.
Citation:
.. code-block::
@article{1998Gradient,
title={Gradient-based learning applied to document recognition},
author={ Lecun, Y. and Bottou, L. },
journal={Proceedings of the IEEE},
volume={86},
number={11},
pages={2278-2324},
year={1998}
}
"""
def __init__(self, num_classes=10, num_channel=1, include_top=True):
super(LeNet5, self).__init__()
self.include_top = include_top
self.conv1 = nn.Conv2d(num_channel, 6, 5, pad_mode='valid')
self.conv2 = nn.Conv2d(6, 16, 5, pad_mode='valid')
self.relu = nn.ReLU()
self.max_pool2d = nn.MaxPool2d(kernel_size=2, stride=2)
if self.include_top:
self.flatten = nn.Flatten()
self.fc1 = nn.Dense(16 * 5 * 5, 120, weight_init=Normal(0.02))
self.fc2 = nn.Dense(120, 84, weight_init=Normal(0.02))
self.fc3 = nn.Dense(84, num_classes, weight_init=Normal(0.02))
def construct(self, x):
"""
LeNet5 construct.
"""
x = self.conv1(x)
x = self.relu(x)
x = self.max_pool2d(x)
x = self.conv2(x)
x = self.relu(x)
x = self.max_pool2d(x)
if self.include_top:
x = self.flatten(x)
x = self.relu(self.fc1(x))
x = self.relu(self.fc2(x))
x = self.fc3(x)
return x