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Update blurpool.py 

clean up code for PR
pull/101/head
Chris Ha 2020-03-11 22:19:10 +09:00
parent 3a287a6e76
commit ce3d82b58b
1 changed files with 9 additions and 23 deletions
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32
timm/models/layers/blurpool.py
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@ -1,7 +1,7 @@
'''independent attempt to implement
MaxBlurPool2d in a more general fashion(separate maxpooling from BlurPool)
which was again inspired by
'''
BlurPool layer inspired by
Kornia's Max_BlurPool2d
and
Making Convolutional Networks Shift-Invariant Again :cite:`zhang2019shiftinvar`
'''
@ -17,8 +17,7 @@ class BlurPool2d(nn.Module):
Corresponds to the Downsample class, which does blurring and subsampling
Args:
channels = Number of input channels
blur_filter_size (int): filter size for blurring. currently supports either 3 or 5 (most common)
defaults to 3.
blur_filter_size (int): binomial filter size for blurring. currently supports 3(default) and 5.
stride (int): downsampling filter stride
Shape:
Returns:
@ -35,16 +34,16 @@ class BlurPool2d(nn.Module):
if blur_filter_size == 3:
pad_size = [1] * 4
blur_matrix = torch.Tensor([[1., 2., 1]]) / 4 # binomial kernel b2
blur_matrix = torch.Tensor([[1., 2., 1]]) / 4 # binomial filter b2
else:
pad_size = [2] * 4
blur_matrix = torch.Tensor([[1., 4., 6., 4., 1.]]) / 16 # binomial filter kernel b4
blur_matrix = torch.Tensor([[1., 4., 6., 4., 1.]]) / 16 # binomial filter b4
self.padding = nn.ReflectionPad2d(pad_size)
blur_filter = blur_matrix * blur_matrix.T
self.register_buffer('blur_filter', blur_filter[None, None, :, :].repeat((self.channels, 1, 1, 1)))
def forward(self, input_tensor: torch.Tensor) -> torch.Tensor: # type: ignore
def forward(self, input_tensor: torch.Tensor) -> torch.Tensor: # type: ignore
if not torch.is_tensor(input_tensor):
raise TypeError("Input input type is not a torch.Tensor. Got {}"
.format(type(input_tensor)))
@ -52,17 +51,4 @@ class BlurPool2d(nn.Module):
raise ValueError("Invalid input shape, we expect BxCxHxW. Got: {}"
.format(input_tensor.shape))
# apply blur_filter on input
return F.conv2d(self.padding(input_tensor), self.blur_filter, stride=self.stride, groups=input_tensor.shape[1])
######################
# functional interface
######################
'''def blur_pool2d() -> torch.Tensor:
r"""Creates a module that computes pools and blurs and downsample a given
feature map.
See :class:`~kornia.contrib.MaxBlurPool2d` for details.
"""
return BlurPool2d(kernel_size, ceil_mode)(input)'''
return F.conv2d(self.padding(input_tensor), self.blur_filter, stride=self.stride, groups=input_tensor.shape[1])