使用 PyTorch,当我有填充时我的 Conv1d 维度如何减少?

With PyTorch, how is my Conv1d dimension reducing when I have padding?

我的conv module是:

        return torch.nn.Sequential(
            torch.nn.Conv1d(
                in_channels=in_channels,
                out_channels=in_channels,
                kernel_size=2,
                stride=1,
                dilation=1,
                padding=1
            ),
            torch.nn.ReLU(),
            torch.nn.Conv1d(
                in_channels=in_channels,
                out_channels=in_channels,
                kernel_size=2,
                stride=1,
                dilation=2,
                padding=1
            ),
            torch.nn.ReLU(),
            torch.nn.Conv1d(
                in_channels=in_channels,
                out_channels=in_channels,
                kernel_size=2,
                stride=1,
                dilation=4,
                padding=1
            ),
            torch.nn.ReLU()
        )

forward 中,我有:

down_out = self.downscale_time_conv(inputs)

inputs.sizetorch.Size([8, 161, 24])。我希望 down_out 具有相同的大小,但它具有:torch.Size([8, 161, 23])

最后一个元素去哪儿了?

答案可以在 Pytorch 在线文档 (here) 上找到。对于每个操作,输出形状都是相对于输入参数表示的:

对于每个 conv1D:

- L1 = 25 → int((24 + 2*1 - 1*(2 - 1) - 1) / 1 + 1)
- L2 = 25 → int((25 + 2*1 - 2*(2 - 1) - 1) / 1 + 1)
- L3 = 23 → int((25 + 2*1 - 4*(2 - 1) - 1) / 1 + 1)

不要忘记Lin是以前的尺寸。