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OctConv:八度卷积复现
来源:cnblogs  作者:华为云开发者联盟  时间:2023/4/12 15:46:39  对本文有异议
摘要:不同于传统的卷积,八度卷积主要针对图像的高频信号与低频信号。

本文分享自华为云社区《OctConv:八度卷积复现》,作者:李长安 。

论文解读

八度卷积于2019年在论文《Drop an Octave: Reducing Spatial Redundancy in Convolutional Neural Networks with Octave Convol》提出,在当时引起了不小的反响。八度卷积对传统的convolution进行改进,以降低空间冗余。其中“Drop an Octave”指降低八个音阶,代表频率减半。

不同于传统的卷积,八度卷积主要针对图像的高频信号与低频信号。首先,我们回忆一下数字图像处理中的高频信号与低频信号的概念。图像中的低频信号和高频信号也叫做低频分量和高频分量。图像中的高频分量,指的是图像强度(亮度/灰度)变化剧烈的像素点,例如边缘(轮廓)、图像的细节处、噪声(即噪点)(该点之所以称为噪点,是因为它与周边像素点灰度值有明显差别,也就是图像强度有剧烈的变化,所以噪声是高频部分)。图像中的低频分量,指的是图像强度(亮度/灰度)变换平缓的像素点,例如大片色块的地方。例如当我们在读书的时候,我们会聚焦于书上的文字而不是书纸本身,这里的文字就是高频分量,白纸即为低频分量。

下图是论文中给出的例子,左图是原图,中图表示低频信号,右图表示高频信号。

在论文中,作者提出较高的频率通常用精细的细节编码,较低的频率通常用全局结构编码。所以作者认为那么既然图像分为高低频,那么卷积产生的特征图自然也存在高低频之分。在图像处理中,模型通过高频特征图去学习图像包含的信息,因为它包含了轮廓、边缘等的信息,有助于进行显著性检测。相反,低频特征图包含的信息较少。如果我们用相同的处理方法来处理高频特征图和低频特征图,显然,前者的效益是远大于后者的。这就是特征图的冗余信息:包含信息较少的低频部分。所以在论文中作者提出了一种分而治之的方法,称之为Octave Feature Representation,对高频特征图与低频特征图分离开来进行处理。如下图所示,作者将低频特征图的分辨率降为1/2,这不仅有助于减少冗余数据,还有利于得到全局信息。

根据尺度空间理念,我们可以知道特征具有尺度不变性和旋转不变性。

  • 尺度不变性:人类在识别一个物体时,不管这个物体或远或近,都能对它进行正确的辨认,这就是所谓的尺度不变性。
  • 旋转不变性:当这个物体发生旋转时,我们照样可以正确地辨认它,这就是所谓的旋转不变性。
    当用一个机器视觉系统分析未知场景时,计算机没有办法预先知识图像中物体尺度,因此,我们需要同时考虑图像在多尺度下的描述,获知感兴趣物体的最佳尺度。例如,高分辨率的图是人近距离的观察得到的,低分辨率的图是远距离观察得到的。

2、复现详情

2.1 Oct-Conv复现

为了同时做到同一频率内的更新和不同频率之间的交流,卷积核分成四部分:

  • 高频到高频的卷积核
  • 高频到低频的卷积核
  • 低频到高频的卷积核
  • 低频到低频的卷积核

下图直观地展示了八度卷积的卷积核,可以看出四个部分共同组成了大小为 k*k 的卷积核。其中,in和out分别表示输入和输出特征图的相关属性,在这篇文章中,输入的低频占比、通道数量都和输出的一致。

在了解了卷积核之后,下面介绍输入如何进行八度卷积操作得到输出结果。如下图所示,低频和高频的输入经过八度卷积操作得到了低频和高频的输出。红色表示高频,蓝色表示低频。绿色的箭头表示同一频率内的更新,红色的箭头表示不同频率之间的交流。

H和W分别表示特征图的长宽,可以看出低频特征图的长宽都是高频特征图的一半。因为分辨率不同,所以不同频率之间交流之前需要进行分辨率的调整:高频到低频需要进行池化(降采样)操作;低频到高频需要进行上采样操作。

  1. import paddle
  2. import paddle.nn as nn
  3. import math
  4. class OctaveConv(nn.Layer):
  5. def __init__(self, in_channels, out_channels, kernel_size, alpha_in=0.5, alpha_out=0.5, stride=1, padding=0, dilation=1,
  6. groups=1, bias=False):
  7. super(OctaveConv, self).__init__()
  8. self.downsample = nn.AvgPool2D(kernel_size=(2, 2), stride=2)
  9. self.upsample = nn.Upsample(scale_factor=2, mode='nearest')
  10. assert stride == 1 or stride == 2, "Stride should be 1 or 2."
  11. self.stride = stride
  12. self.is_dw = groups == in_channels
  13. assert 0 <= alpha_in <= 1 and 0 <= alpha_out <= 1, "Alphas should be in the interval from 0 to 1."
  14. self.alpha_in, self.alpha_out = alpha_in, alpha_out
  15. self.conv_l2l = None if alpha_in == 0 or alpha_out == 0 else nn.Conv2D(int(alpha_in * in_channels), int(alpha_out * out_channels),
  16. kernel_size, 1, padding, dilation, math.ceil(alpha_in * groups))
  17. self.conv_l2h = None if alpha_in == 0 or alpha_out == 1 or self.is_dw else nn.Conv2D(int(alpha_in * in_channels), out_channels - int(alpha_out * out_channels),
  18. kernel_size, 1, padding, dilation, groups)
  19. self.conv_h2l = None if alpha_in == 1 or alpha_out == 0 or self.is_dw else nn.Conv2D(in_channels - int(alpha_in * in_channels), int(alpha_out * out_channels),
  20. kernel_size, 1, padding, dilation, groups)
  21. self.conv_h2h = None if alpha_in == 1 or alpha_out == 1 else nn.Conv2D(in_channels - int(alpha_in * in_channels), out_channels - int(alpha_out * out_channels),
  22. kernel_size, 1, padding, dilation, math.ceil(groups - alpha_in * groups))
  23. def forward(self, x):
  24. x_h, x_l = x if type(x) is tuple else (x, None)
  25. x_h = self.downsample(x_h) if self.stride == 2 else x_h
  26. x_h2h = self.conv_h2h(x_h)
  27. x_h2l = self.conv_h2l(self.downsample(x_h)) if self.alpha_out > 0 and not self.is_dw else None
  28. if x_l is not None:
  29. x_l2l = self.downsample(x_l) if self.stride == 2 else x_l
  30. x_l2l = self.conv_l2l(x_l2l) if self.alpha_out > 0 else None
  31. if self.is_dw:
  32. return x_h2h, x_l2l
  33. else:
  34. x_l2h = self.conv_l2h(x_l)
  35. x_l2h = self.upsample(x_l2h) if self.stride == 1 else x_l2h
  36. x_h = x_l2h + x_h2h
  37. x_l = x_h2l + x_l2l if x_h2l is not None and x_l2l is not None else None
  38. return x_h, x_l
  39. else:
  40. return x_h2h, x_h2l
  41. class Conv_BN(nn.Layer):
  42. def __init__(self, in_channels, out_channels, kernel_size, alpha_in=0.5, alpha_out=0.5, stride=1, padding=0, dilation=1,
  43. groups=1, bias=False, norm_layer=nn.BatchNorm2D):
  44. super(Conv_BN, self).__init__()
  45. self.conv = OctaveConv(in_channels, out_channels, kernel_size, alpha_in, alpha_out, stride, padding, dilation,
  46. groups, bias)
  47. self.bn_h = None if alpha_out == 1 else norm_layer(int(out_channels * (1 - alpha_out)))
  48. self.bn_l = None if alpha_out == 0 else norm_layer(int(out_channels * alpha_out))
  49. def forward(self, x):
  50. x_h, x_l = self.conv(x)
  51. x_h = self.bn_h(x_h)
  52. x_l = self.bn_l(x_l) if x_l is not None else None
  53. return x_h, x_l
  54. class Conv_BN_ACT(nn.Layer):
  55. def __init__(self, in_channels=3, out_channels=32, kernel_size=3, alpha_in=0.5, alpha_out=0.5, stride=1, padding=0, dilation=1,
  56. groups=1, bias=False, norm_layer=nn.BatchNorm2D, activation_layer=nn.ReLU):
  57. super(Conv_BN_ACT, self).__init__()
  58. self.conv = OctaveConv(in_channels, out_channels, kernel_size, alpha_in, alpha_out, stride, padding, dilation,
  59. groups, bias)
  60. self.bn_h = None if alpha_out == 1 else norm_layer(int(out_channels * (1 - alpha_out)))
  61. self.bn_l = None if alpha_out == 0 else norm_layer(int(out_channels * alpha_out))
  62. self.act = activation_layer()
  63. def forward(self, x):
  64. x_h, x_l = self.conv(x)
  65. x_h = self.act(self.bn_h(x_h))
  66. x_l = self.act(self.bn_l(x_l)) if x_l is not None else None
  67. return x_h, x_l

2.2 Oct-Mobilnetv1复现

Oct-Mobilnetv1的复现即将Mobilnetv1中的原始的Conv2D替换为Oct-Conv,其他均保持不变,在后面打印了Oct-Mobilnetv1的网络结构以及参数量,方便大家查看。

  1. # Oct-Mobilnetv1
  2. import paddle.nn as nn
  3. __all__ = ['oct_mobilenet']
  4. def conv_bn(inp, oup, stride):
  5. return nn.Sequential(
  6. nn.Conv2D(inp, oup, 3, stride, 1),
  7. nn.BatchNorm2D(oup),
  8. nn.ReLU()
  9. )
  10. def conv_dw(inp, oup, stride, alpha_in=0.5, alpha_out=0.5):
  11. return nn.Sequential(
  12. Conv_BN_ACT(inp, inp, kernel_size=3, stride=stride, padding=1, groups=inp, alpha_in=alpha_in, alpha_out=alpha_in if alpha_out != alpha_in else alpha_out),
  13. Conv_BN_ACT(inp, oup, kernel_size=1, alpha_in=alpha_in, alpha_out=alpha_out)
  14. )
  15. class OctMobileNet(nn.Layer):
  16. def __init__(self, num_classes=1000):
  17. super(OctMobileNet, self).__init__()
  18. self.features = nn.Sequential(
  19. conv_bn( 3, 32, 2),
  20. conv_dw( 32, 64, 1, 0, 0.5),
  21. conv_dw( 64, 128, 2),
  22. conv_dw(128, 128, 1),
  23. conv_dw(128, 256, 2),
  24. conv_dw(256, 256, 1),
  25. conv_dw(256, 512, 2),
  26. conv_dw(512, 512, 1),
  27. conv_dw(512, 512, 1),
  28. conv_dw(512, 512, 1),
  29. conv_dw(512, 512, 1),
  30. conv_dw(512, 512, 1, 0.5, 0),
  31. conv_dw(512, 1024, 2, 0, 0),
  32. conv_dw(1024, 1024, 1, 0, 0),
  33. )
  34. self.avgpool = nn.AdaptiveAvgPool2D((1, 1))
  35. self.fc = nn.Linear(1024, num_classes)
  36. def forward(self, x):
  37. x_h, x_l = self.features(x)
  38. x = self.avgpool(x_h)
  39. x = x.reshape([-1, 1024])
  40. x = self.fc(x)
  41. return x
  42. def oct_mobilenet(**kwargs):
  43. """
  44. Constructs a Octave MobileNet V1 model
  45. """
  46. return OctMobileNet(**kwargs)

2.3 OctResNet的复现

Oct-ResNet的复现即将ResNet中的原始的Conv2D替换为Oct-Conv,其他均保持不变,在后面打印了Oct-ResNet的网络结构以及参数量,方便大家查看。

  1. import paddle.nn as nn
  2. __all__ = ['OctResNet', 'oct_resnet50', 'oct_resnet101', 'oct_resnet152', 'oct_resnet200']
  3. class Bottleneck(nn.Layer):
  4. expansion = 4
  5. def __init__(self, inplanes, planes, stride=1, downsample=None, groups=1,
  6. base_width=64, alpha_in=0.5, alpha_out=0.5, norm_layer=None, output=False):
  7. super(Bottleneck, self).__init__()
  8. if norm_layer is None:
  9. norm_layer = nn.BatchNorm2D
  10. width = int(planes * (base_width / 64.)) * groups
  11. # Both self.conv2 and self.downsample layers downsample the input when stride != 1
  12. self.conv1 = Conv_BN_ACT(inplanes, width, kernel_size=1, alpha_in=alpha_in, alpha_out=alpha_out, norm_layer=norm_layer)
  13. self.conv2 = Conv_BN_ACT(width, width, kernel_size=3, stride=stride, padding=1, groups=groups, norm_layer=norm_layer,
  14. alpha_in=0 if output else 0.5, alpha_out=0 if output else 0.5)
  15. self.conv3 = Conv_BN(width, planes * self.expansion, kernel_size=1, norm_layer=norm_layer,
  16. alpha_in=0 if output else 0.5, alpha_out=0 if output else 0.5)
  17. self.relu = nn.ReLU()
  18. self.downsample = downsample
  19. self.stride = stride
  20. def forward(self, x):
  21. identity_h = x[0] if type(x) is tuple else x
  22. identity_l = x[1] if type(x) is tuple else None
  23. x_h, x_l = self.conv1(x)
  24. x_h, x_l = self.conv2((x_h, x_l))
  25. x_h, x_l = self.conv3((x_h, x_l))
  26. if self.downsample is not None:
  27. identity_h, identity_l = self.downsample(x)
  28. x_h += identity_h
  29. x_l = x_l + identity_l if identity_l is not None else None
  30. x_h = self.relu(x_h)
  31. x_l = self.relu(x_l) if x_l is not None else None
  32. return x_h, x_l
  33. class OctResNet(nn.Layer):
  34. def __init__(self, block, layers, num_classes=1000, zero_init_residual=False,
  35. groups=1, width_per_group=64, norm_layer=None):
  36. super(OctResNet, self).__init__()
  37. if norm_layer is None:
  38. norm_layer = nn.BatchNorm2D
  39. self.inplanes = 64
  40. self.groups = groups
  41. self.base_width = width_per_group
  42. self.conv1 = nn.Conv2D(3, self.inplanes, kernel_size=7, stride=2, padding=3,
  43. )
  44. self.bn1 = norm_layer(self.inplanes)
  45. self.relu = nn.ReLU()
  46. self.maxpool = nn.MaxPool2D(kernel_size=3, stride=2, padding=1)
  47. self.layer1 = self._make_layer(block, 64, layers[0], norm_layer=norm_layer, alpha_in=0)
  48. self.layer2 = self._make_layer(block, 128, layers[1], stride=2, norm_layer=norm_layer)
  49. self.layer3 = self._make_layer(block, 256, layers[2], stride=2, norm_layer=norm_layer)
  50. self.layer4 = self._make_layer(block, 512, layers[3], stride=2, norm_layer=norm_layer, alpha_out=0, output=True)
  51. self.avgpool = nn.AdaptiveAvgPool2D((1, 1))
  52. self.fc = nn.Linear(512 * block.expansion, num_classes)
  53. def _make_layer(self, block, planes, blocks, stride=1, alpha_in=0.5, alpha_out=0.5, norm_layer=None, output=False):
  54. if norm_layer is None:
  55. norm_layer = nn.BatchNorm2D
  56. downsample = None
  57. if stride != 1 or self.inplanes != planes * block.expansion:
  58. downsample = nn.Sequential(
  59. Conv_BN(self.inplanes, planes * block.expansion, kernel_size=1, stride=stride, alpha_in=alpha_in, alpha_out=alpha_out)
  60. )
  61. layers = []
  62. layers.append(block(self.inplanes, planes, stride, downsample, self.groups,
  63. self.base_width, alpha_in, alpha_out, norm_layer, output))
  64. self.inplanes = planes * block.expansion
  65. for _ in range(1, blocks):
  66. layers.append(block(self.inplanes, planes, groups=self.groups,
  67. base_width=self.base_width, norm_layer=norm_layer,
  68. alpha_in=0 if output else 0.5, alpha_out=0 if output else 0.5, output=output))
  69. return nn.Sequential(*layers)
  70. def forward(self, x):
  71. x = self.conv1(x)
  72. x = self.bn1(x)
  73. x = self.relu(x)
  74. x = self.maxpool(x)
  75. x_h, x_l = self.layer1(x)
  76. x_h, x_l = self.layer2((x_h,x_l))
  77. x_h, x_l = self.layer3((x_h,x_l))
  78. x_h, x_l = self.layer4((x_h,x_l))
  79. x = self.avgpool(x_h)
  80. x = x.reshape([x.shape[0], -1])
  81. x = self.fc(x)
  82. return x
  83. def oct_resnet50(pretrained=False, **kwargs):
  84. """Constructs a Octave ResNet-50 model.
  85. Args:
  86. pretrained (bool): If True, returns a model pre-trained on ImageNet
  87. """
  88. model = OctResNet(Bottleneck, [3, 4, 6, 3], **kwargs)
  89. return model
  90. def oct_resnet101(pretrained=False, **kwargs):
  91. """Constructs a Octave ResNet-101 model.
  92. Args:
  93. pretrained (bool): If True, returns a model pre-trained on ImageNet
  94. """
  95. model = OctResNet(Bottleneck, [3, 4, 23, 3], **kwargs)
  96. return model
  97. def oct_resnet152(pretrained=False, **kwargs):
  98. """Constructs a Octave ResNet-152 model.
  99. Args:
  100. pretrained (bool): If True, returns a model pre-trained on ImageNet
  101. """
  102. model = OctResNet(Bottleneck, [3, 8, 36, 3], **kwargs)
  103. return model
  104. def oct_resnet200(pretrained=False, **kwargs):
  105. """Constructs a Octave ResNet-200 model.
  106. Args:
  107. pretrained (bool): If True, returns a model pre-trained on ImageNet
  108. """
  109. model = OctResNet(Bottleneck, [3, 24, 36, 3], **kwargs)
  110. return model

3、对比实验

实验数据:Cifar10

CIFAR-10 是由 Hinton 的学生 Alex Krizhevsky 和 Ilya Sutskever 整理的一个用于识别普适物体的小型数据集。一共包含 10 个类别的 RGB 彩色图 片:飞机( a叩lane )、汽车( automobile )、鸟类( bird )、猫( cat )、鹿( deer )、狗( dog )、蛙类( frog )、马( horse )、船( ship )和卡车( truck )。图片的尺寸为 32×32 ,数据集中一共有 50000 张训练圄片和 10000 张测试图片。 CIFAR-10 的图片样例如图所示。

3.1 Oct_MobilNetv1模型网络结构可视化

  1. Octmobilnet_model = oct_mobilenet(num_classes=10)
  2. # inputs = paddle.randn((1, 2, 224, 224))
  3. # print(model(inputs))
  4. paddle.summary(Octmobilnet_model,(16,3,224,224))

3.2 Oct_MobilNetV1模型训练

  1. import paddle
  2. from paddle.metric import Accuracy
  3. from paddle.vision.transforms import Compose, Normalize, Resize, Transpose, ToTensor
  4. callback = paddle.callbacks.VisualDL(log_dir='visualdl_log_dir_octmobilenet')
  5. normalize = Normalize(mean=[0.5, 0.5, 0.5],
  6. std=[0.5, 0.5, 0.5],
  7. data_format='HWC')
  8. transform = Compose([ToTensor(), Normalize(), Resize(size=(224,224))])
  9. cifar10_train = paddle.vision.datasets.Cifar10(mode='train',
  10. transform=transform)
  11. cifar10_test = paddle.vision.datasets.Cifar10(mode='test',
  12. transform=transform)
  13. # 构建训练集数据加载器
  14. train_loader = paddle.io.DataLoader(cifar10_train, batch_size=768, shuffle=True, drop_last=True)
  15. # 构建测试集数据加载器
  16. test_loader = paddle.io.DataLoader(cifar10_test, batch_size=768, shuffle=True, drop_last=True)
  17. Octmobilnet_model = paddle.Model(oct_mobilenet(num_classes=10))
  18. optim = paddle.optimizer.Adam(learning_rate=0.001, parameters=Octmobilnet_model.parameters())
  19. Octmobilnet_model.prepare(
  20. optim,
  21. paddle.nn.CrossEntropyLoss(),
  22. Accuracy()
  23. )
  24. Octmobilnet_model.fit(train_data=train_loader,
  25. eval_data=test_loader,
  26. epochs=12,
  27. callbacks=callback,
  28. verbose=1
  29. )

3.3 MobileNetV1模型网络结构可视化

  1. from paddle.vision.models import MobileNetV1
  2. mobile_model = MobileNetV1(num_classes=10)
  3. # inputs = paddle.randn((1, 2, 224, 224))
  4. # print(model(inputs))
  5. paddle.summary(mobile_model,(16,3,224,224))

3.4 MobileNetV1模型训练

  1. import paddle
  2. from paddle.metric import Accuracy
  3. from paddle.vision.transforms import Compose, Normalize, Resize, Transpose, ToTensor
  4. callback = paddle.callbacks.VisualDL(log_dir='visualdl_log_dir_mobilenet')
  5. normalize = Normalize(mean=[0.5, 0.5, 0.5],
  6. std=[0.5, 0.5, 0.5],
  7. data_format='HWC')
  8. transform = Compose([ToTensor(), Normalize(), Resize(size=(224,224))])
  9. cifar10_train = paddle.vision.datasets.Cifar10(mode='train',
  10. transform=transform)
  11. cifar10_test = paddle.vision.datasets.Cifar10(mode='test',
  12. transform=transform)
  13. # 构建训练集数据加载器
  14. train_loader = paddle.io.DataLoader(cifar10_train, batch_size=768, shuffle=True, drop_last=True)
  15. # 构建测试集数据加载器
  16. test_loader = paddle.io.DataLoader(cifar10_test, batch_size=768, shuffle=True, drop_last=True)
  17. mobile_model = paddle.Model(MobileNetV1(num_classes=10))
  18. optim = paddle.optimizer.Adam(learning_rate=0.001, parameters=mobile_model.parameters())
  19. mobile_model.prepare(
  20. optim,
  21. paddle.nn.CrossEntropyLoss(),
  22. Accuracy()
  23. )
  24. mobile_model.fit(train_data=train_loader,
  25. eval_data=test_loader,
  26. epochs=12,
  27. callbacks=callback,
  28. verbose=1
  29. )

3.5 Oct_ResNet50模型网络结构可视化

  1. octresnet50_model = oct_resnet50(num_classes=10)
  2. paddle.summary(octresnet50_model,(16,3,224,224))

3.6 Oct_ResNet50模型训练

  1. import paddle
  2. from paddle.metric import Accuracy
  3. from paddle.vision.transforms import Compose, Normalize, Resize, Transpose, ToTensor
  4. callback = paddle.callbacks.VisualDL(log_dir='visualdl_log_dir_octresnet')
  5. normalize = Normalize(mean=[0.5, 0.5, 0.5],
  6. std=[0.5, 0.5, 0.5],
  7. data_format='HWC')
  8. transform = Compose([ToTensor(), Normalize(), Resize(size=(224,224))])
  9. cifar10_train = paddle.vision.datasets.Cifar10(mode='train',
  10. transform=transform)
  11. cifar10_test = paddle.vision.datasets.Cifar10(mode='test',
  12. transform=transform)
  13. # 构建训练集数据加载器
  14. train_loader = paddle.io.DataLoader(cifar10_train, batch_size=256, shuffle=True, drop_last=True)
  15. # 构建测试集数据加载器
  16. test_loader = paddle.io.DataLoader(cifar10_test, batch_size=256, shuffle=True, drop_last=True)
  17. oct_resnet50 = paddle.Model(oct_resnet50(num_classes=10))
  18. optim = paddle.optimizer.Adam(learning_rate=0.001, parameters=oct_resnet50.parameters())
  19. oct_resnet50.prepare(
  20. optim,
  21. paddle.nn.CrossEntropyLoss(),
  22. Accuracy()
  23. )
  24. oct_resnet50.fit(train_data=train_loader,
  25. eval_data=test_loader,
  26. epochs=12,
  27. callbacks=callback,
  28. verbose=1
  29. )

3.7 ResNet50模型网络结构可视化

  1. import paddle
  2. # build model
  3. resmodel = resnet50(num_classes=10)
  4. paddle.summary(resmodel,(16,3,224,224))

3.8 ResNet50模型训练

  1. import paddle
  2. from paddle.metric import Accuracy
  3. from paddle.vision.transforms import Compose, Normalize, Resize, Transpose, ToTensor
  4. from paddle.vision.models import resnet50
  5. callback = paddle.callbacks.VisualDL(log_dir='visualdl_log_dir_resnet')
  6. normalize = Normalize(mean=[0.5, 0.5, 0.5],
  7. std=[0.5, 0.5, 0.5],
  8. data_format='HWC')
  9. transform = Compose([ToTensor(), Normalize(), Resize(size=(224,224))])
  10. cifar10_train = paddle.vision.datasets.Cifar10(mode='train',
  11. transform=transform)
  12. cifar10_test = paddle.vision.datasets.Cifar10(mode='test',
  13. transform=transform)
  14. # 构建训练集数据加载器
  15. train_loader = paddle.io.DataLoader(cifar10_train, batch_size=256, shuffle=True, drop_last=True)
  16. # 构建测试集数据加载器
  17. test_loader = paddle.io.DataLoader(cifar10_test, batch_size=256, shuffle=True, drop_last=True)
  18. res_model = paddle.Model(resnet50(num_classes=10))
  19. optim = paddle.optimizer.Adam(learning_rate=0.001, parameters=res_model.parameters())
  20. res_model.prepare(
  21. optim,
  22. paddle.nn.CrossEntropyLoss(),
  23. Accuracy()
  24. )
  25. res_model.fit(train_data=train_loader,
  26. eval_data=test_loader,
  27. epochs=12,
  28. callbacks=callback,
  29. verbose=1
  30. )

3.9 实验结果

本小节提供消融实验的结果以及可视化训练结果,共计包含四个实验,分别为octmobinetv1、mobinetv1、octresnet50以及resnet50在数据集Cifar10上的结果对比。

<style> table { margin: auto; } </style>

图1:Oct_MobileNetV1对比实验结果图

图2:Oct_ResNet50对比实验结果图

4、参考资料

d-li14/octconv.pytorch

神经网络学习之OctConv:八度卷积

Drop an Octave: Reducing Spatial Redundancy in Convolutional Neural Networks with Octave Convolution

5、总结

目前我们得到的结论与论文中的结论不符,论文提供的代码为MXnet框架,本复现参考了PyTorch版本的复现,不能确定是否为框架原因,或者一些训练设置原因,比如初始化方式或模型迭代次数不够,有待查证,大家感兴趣的也可以就这个问题与我在评论区进行交流。

 

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原文链接:https://www.cnblogs.com/huaweiyun/p/17310055.html

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