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@@ -0,0 +1,689 @@
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+import math
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+import torch
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+import torch.nn as nn
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+import torch.nn.functional as F
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+
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+
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+class _BatchNorm1d(nn.Module):
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+ def __init__(
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+ self,
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+ input_shape=None,
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+ input_size=None,
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+ eps=1e-05,
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+ momentum=0.1,
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+ affine=True,
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+ track_running_stats=True,
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+ combine_batch_time=False,
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+ skip_transpose=False,
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+ ):
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+ super().__init__()
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+ self.combine_batch_time = combine_batch_time
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+ self.skip_transpose = skip_transpose
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+
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+ if input_size is None and skip_transpose:
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+ input_size = input_shape[1]
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+ elif input_size is None:
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+ input_size = input_shape[-1]
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+
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+ self.norm = nn.BatchNorm1d(
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+ input_size,
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+ eps=eps,
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+ momentum=momentum,
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+ affine=affine,
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+ track_running_stats=track_running_stats,
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+ )
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+
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+ def forward(self, x):
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+ shape_or = x.shape
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+ if self.combine_batch_time:
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+ if x.ndim == 3:
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+ x = x.reshape(shape_or[0] * shape_or[1], shape_or[2])
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+ else:
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+ x = x.reshape(
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+ shape_or[0] * shape_or[1], shape_or[3], shape_or[2]
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+ )
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+
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+ elif not self.skip_transpose:
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+ x = x.transpose(-1, 1)
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+
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+ x_n = self.norm(x)
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+
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+ if self.combine_batch_time:
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+ x_n = x_n.reshape(shape_or)
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+ elif not self.skip_transpose:
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+ x_n = x_n.transpose(1, -1)
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+
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+ return x_n
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+
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+
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+class _Conv1d(nn.Module):
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+ def __init__(
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+ self,
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+ out_channels,
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+ kernel_size,
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+ input_shape=None,
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+ in_channels=None,
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+ stride=1,
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+ dilation=1,
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+ padding="same",
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+ groups=1,
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+ bias=True,
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+ padding_mode="reflect",
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+ skip_transpose=False,
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+ ):
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+ super().__init__()
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+ self.kernel_size = kernel_size
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+ self.stride = stride
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+ self.dilation = dilation
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+ self.padding = padding
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+ self.padding_mode = padding_mode
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+ self.unsqueeze = False
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+ self.skip_transpose = skip_transpose
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+
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+ if input_shape is None and in_channels is None:
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+ raise ValueError("Must provide one of input_shape or in_channels")
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+
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+ if in_channels is None:
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+ in_channels = self._check_input_shape(input_shape)
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+
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+ self.conv = nn.Conv1d(
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+ in_channels,
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+ out_channels,
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+ self.kernel_size,
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+ stride=self.stride,
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+ dilation=self.dilation,
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+ padding=0,
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+ groups=groups,
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+ bias=bias,
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+ )
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+
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+ def forward(self, x):
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+ if not self.skip_transpose:
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+ x = x.transpose(1, -1)
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+
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+ if self.unsqueeze:
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+ x = x.unsqueeze(1)
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+
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+ if self.padding == "same":
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+ x = self._manage_padding(
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+ x, self.kernel_size, self.dilation, self.stride
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+ )
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+
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+ elif self.padding == "causal":
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+ num_pad = (self.kernel_size - 1) * self.dilation
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+ x = F.pad(x, (num_pad, 0))
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+
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+ elif self.padding == "valid":
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+ pass
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+
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+ else:
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+ raise ValueError(
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+ "Padding must be 'same', 'valid' or 'causal'. Got "
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+ + self.padding
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+ )
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+
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+ wx = self.conv(x)
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+
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+ if self.unsqueeze:
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+ wx = wx.squeeze(1)
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+
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+ if not self.skip_transpose:
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+ wx = wx.transpose(1, -1)
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+
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+ return wx
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+
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+ def _manage_padding(
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+ self, x, kernel_size: int, dilation: int, stride: int,
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+ ):
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+ # Detecting input shape
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+ L_in = x.shape[-1]
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+
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+ # Time padding
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+ padding = get_padding_elem(L_in, stride, kernel_size, dilation)
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+
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+ # Applying padding
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+ x = F.pad(x, padding, mode=self.padding_mode)
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+
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+ return x
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+
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+ def _check_input_shape(self, shape):
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+ """Checks the input shape and returns the number of input channels.
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+ """
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+
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+ if len(shape) == 2:
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+ self.unsqueeze = True
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+ in_channels = 1
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+ elif self.skip_transpose:
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+ in_channels = shape[1]
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+ elif len(shape) == 3:
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+ in_channels = shape[2]
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+ else:
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+ raise ValueError(
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+ "conv1d expects 2d, 3d inputs. Got " + str(len(shape))
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+ )
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+
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+ # Kernel size must be odd
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+ if self.kernel_size % 2 == 0:
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+ raise ValueError(
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+ "The field kernel size must be an odd number. Got %s."
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+ % (self.kernel_size)
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+ )
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+ return in_channels
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+
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+
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+def get_padding_elem(L_in: int, stride: int, kernel_size: int, dilation: int):
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+ if stride > 1:
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+ n_steps = math.ceil(((L_in - kernel_size * dilation) / stride) + 1)
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+ L_out = stride * (n_steps - 1) + kernel_size * dilation
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+ padding = [kernel_size // 2, kernel_size // 2]
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+
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+ else:
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+ L_out = (L_in - dilation * (kernel_size - 1) - 1) // stride + 1
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+
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+ padding = [(L_in - L_out) // 2, (L_in - L_out) // 2]
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+ return padding
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+
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+
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+# Skip transpose as much as possible for efficiency
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+class Conv1d(_Conv1d):
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+ def __init__(self, *args, **kwargs):
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+ super().__init__(skip_transpose=True, *args, **kwargs)
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+
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+
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+class BatchNorm1d(_BatchNorm1d):
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+ def __init__(self, *args, **kwargs):
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+ super().__init__(skip_transpose=True, *args, **kwargs)
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+
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+
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+def length_to_mask(length, max_len=None, dtype=None, device=None):
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+ assert len(length.shape) == 1
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+
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+ if max_len is None:
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+ max_len = length.max().long().item() # using arange to generate mask
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+ mask = torch.arange(
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+ max_len, device=length.device, dtype=length.dtype
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+ ).expand(len(length), max_len) < length.unsqueeze(1)
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+
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+ if dtype is None:
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+ dtype = length.dtype
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+
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+ if device is None:
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+ device = length.device
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+
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+ mask = torch.as_tensor(mask, dtype=dtype, device=device)
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+ return mask
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+
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+
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+class TDNNBlock(nn.Module):
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+ def __init__(
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+ self,
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+ in_channels,
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+ out_channels,
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+ kernel_size,
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+ dilation,
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+ activation=nn.ReLU,
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+ groups=1,
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+ ):
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+ super(TDNNBlock, self).__init__()
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+ self.conv = Conv1d(
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+ in_channels=in_channels,
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+ out_channels=out_channels,
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+ kernel_size=kernel_size,
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+ dilation=dilation,
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+ groups=groups,
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+ )
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+ self.activation = activation()
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+ self.norm = BatchNorm1d(input_size=out_channels)
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+
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+ def forward(self, x):
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+ return self.norm(self.activation(self.conv(x)))
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+
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+
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+class Res2NetBlock(torch.nn.Module):
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+ """An implementation of Res2NetBlock w/ dilation.
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+
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+ Arguments
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+ ---------
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+ in_channels : int
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+ The number of channels expected in the input.
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+ out_channels : int
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+ The number of output channels.
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+ scale : int
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+ The scale of the Res2Net block.
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+ kernel_size: int
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+ The kernel size of the Res2Net block.
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+ dilation : int
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+ The dilation of the Res2Net block.
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+
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+ Example
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+ -------
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+ >>> inp_tensor = torch.rand([8, 120, 64]).transpose(1, 2)
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+ >>> layer = Res2NetBlock(64, 64, scale=4, dilation=3)
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+ >>> out_tensor = layer(inp_tensor).transpose(1, 2)
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+ >>> out_tensor.shape
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+ torch.Size([8, 120, 64])
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+ """
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+
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+ def __init__(
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+ self, in_channels, out_channels, scale=8, kernel_size=3, dilation=1
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+ ):
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+ super(Res2NetBlock, self).__init__()
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+ assert in_channels % scale == 0
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+ assert out_channels % scale == 0
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+
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+ in_channel = in_channels // scale
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+ hidden_channel = out_channels // scale
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+
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+ self.blocks = nn.ModuleList(
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+ [
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+ TDNNBlock(
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+ in_channel,
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+ hidden_channel,
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+ kernel_size=kernel_size,
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+ dilation=dilation,
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+ )
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+ for i in range(scale - 1)
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+ ]
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+ )
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+ self.scale = scale
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+
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+ def forward(self, x):
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+ y = []
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+ for i, x_i in enumerate(torch.chunk(x, self.scale, dim=1)):
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+ if i == 0:
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+ y_i = x_i
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+ elif i == 1:
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+ y_i = self.blocks[i - 1](x_i)
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+ else:
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+ y_i = self.blocks[i - 1](x_i + y_i)
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+ y.append(y_i)
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+ y = torch.cat(y, dim=1)
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+ return y
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+
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+
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+class SEBlock(nn.Module):
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+ """An implementation of squeeze-and-excitation block.
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+
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+ Arguments
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+ ---------
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+ in_channels : int
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+ The number of input channels.
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+ se_channels : int
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+ The number of output channels after squeeze.
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+ out_channels : int
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+ The number of output channels.
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+
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+ Example
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+ -------
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+ >>> inp_tensor = torch.rand([8, 120, 64]).transpose(1, 2)
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+ >>> se_layer = SEBlock(64, 16, 64)
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+ >>> lengths = torch.rand((8,))
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+ >>> out_tensor = se_layer(inp_tensor, lengths).transpose(1, 2)
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+ >>> out_tensor.shape
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+ torch.Size([8, 120, 64])
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+ """
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+
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+ def __init__(self, in_channels, se_channels, out_channels):
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+ super(SEBlock, self).__init__()
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+
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+ self.conv1 = Conv1d(
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+ in_channels=in_channels, out_channels=se_channels, kernel_size=1
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+ )
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+ self.relu = torch.nn.ReLU(inplace=True)
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+ self.conv2 = Conv1d(
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+ in_channels=se_channels, out_channels=out_channels, kernel_size=1
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+ )
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+ self.sigmoid = torch.nn.Sigmoid()
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+
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+ def forward(self, x, lengths=None):
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+ L = x.shape[-1]
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+ if lengths is not None:
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+ mask = length_to_mask(lengths * L, max_len=L, device=x.device)
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+ mask = mask.unsqueeze(1)
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+ total = mask.sum(dim=2, keepdim=True)
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+ s = (x * mask).sum(dim=2, keepdim=True) / total
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+ else:
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+ s = x.mean(dim=2, keepdim=True)
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+
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+ s = self.relu(self.conv1(s))
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+ s = self.sigmoid(self.conv2(s))
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+
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+ return s * x
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+
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+
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+class AttentiveStatisticsPooling(nn.Module):
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+ """This class implements an attentive statistic pooling layer for each channel.
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+ It returns the concatenated mean and std of the input tensor.
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+
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+ Arguments
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+ ---------
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+ channels: int
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+ The number of input channels.
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+ attention_channels: int
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+ The number of attention channels.
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+
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+ Example
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+ -------
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+ >>> inp_tensor = torch.rand([8, 120, 64]).transpose(1, 2)
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+ >>> asp_layer = AttentiveStatisticsPooling(64)
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+ >>> lengths = torch.rand((8,))
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+ >>> out_tensor = asp_layer(inp_tensor, lengths).transpose(1, 2)
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+ >>> out_tensor.shape
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+ torch.Size([8, 1, 128])
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+ """
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+
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+ def __init__(self, channels, attention_channels=128, global_context=True):
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+ super().__init__()
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+
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+ self.eps = 1e-12
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+ self.global_context = global_context
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+ if global_context:
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+ self.tdnn = TDNNBlock(channels * 3, attention_channels, 1, 1)
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+ else:
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+ self.tdnn = TDNNBlock(channels, attention_channels, 1, 1)
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+ self.tanh = nn.Tanh()
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+ self.conv = Conv1d(
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+ in_channels=attention_channels, out_channels=channels, kernel_size=1
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+ )
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+
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+ def forward(self, x, lengths=None):
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+ """Calculates mean and std for a batch (input tensor).
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+
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+ Arguments
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+ ---------
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+ x : torch.Tensor
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+ Tensor of shape [N, C, L].
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+ """
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+ L = x.shape[-1]
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+
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+ def _compute_statistics(x, m, dim=2, eps=self.eps):
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+ mean = (m * x).sum(dim)
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+ std = torch.sqrt(
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+ (m * (x - mean.unsqueeze(dim)).pow(2)).sum(dim).clamp(eps)
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+ )
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+ return mean, std
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+
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+ if lengths is None:
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+ lengths = torch.ones(x.shape[0], device=x.device)
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+
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+ # Make binary mask of shape [N, 1, L]
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+ mask = length_to_mask(lengths * L, max_len=L, device=x.device)
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+ mask = mask.unsqueeze(1)
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+
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+ # Expand the temporal context of the pooling layer by allowing the
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+ # self-attention to look at global properties of the utterance.
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+ if self.global_context:
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+ # torch.std is unstable for backward computation
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+ # https://github.com/pytorch/pytorch/issues/4320
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+ total = mask.sum(dim=2, keepdim=True).float()
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+ mean, std = _compute_statistics(x, mask / total)
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+ mean = mean.unsqueeze(2).repeat(1, 1, L)
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+ std = std.unsqueeze(2).repeat(1, 1, L)
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+ attn = torch.cat([x, mean, std], dim=1)
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+ else:
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+ attn = x
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+
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+ # Apply layers
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+ attn = self.conv(self.tanh(self.tdnn(attn)))
|
|
|
+
|
|
|
+ # Filter out zero-paddings
|
|
|
+ attn = attn.masked_fill(mask == 0, float("-inf"))
|
|
|
+
|
|
|
+ attn = F.softmax(attn, dim=2)
|
|
|
+ mean, std = _compute_statistics(x, attn)
|
|
|
+ # Append mean and std of the batch
|
|
|
+ pooled_stats = torch.cat((mean, std), dim=1)
|
|
|
+ pooled_stats = pooled_stats.unsqueeze(2)
|
|
|
+
|
|
|
+ return pooled_stats
|
|
|
+
|
|
|
+
|
|
|
+class SERes2NetBlock(nn.Module):
|
|
|
+ """An implementation of building block in ECAPA-TDNN, i.e.,
|
|
|
+ TDNN-Res2Net-TDNN-SEBlock.
|
|
|
+
|
|
|
+ Arguments
|
|
|
+ ----------
|
|
|
+ out_channels: int
|
|
|
+ The number of output channels.
|
|
|
+ res2net_scale: int
|
|
|
+ The scale of the Res2Net block.
|
|
|
+ kernel_size: int
|
|
|
+ The kernel size of the TDNN blocks.
|
|
|
+ dilation: int
|
|
|
+ The dilation of the Res2Net block.
|
|
|
+ activation : torch class
|
|
|
+ A class for constructing the activation layers.
|
|
|
+ groups: int
|
|
|
+ Number of blocked connections from input channels to output channels.
|
|
|
+
|
|
|
+ Example
|
|
|
+ -------
|
|
|
+ >>> x = torch.rand(8, 120, 64).transpose(1, 2)
|
|
|
+ >>> conv = SERes2NetBlock(64, 64, res2net_scale=4)
|
|
|
+ >>> out = conv(x).transpose(1, 2)
|
|
|
+ >>> out.shape
|
|
|
+ torch.Size([8, 120, 64])
|
|
|
+ """
|
|
|
+
|
|
|
+ def __init__(
|
|
|
+ self,
|
|
|
+ in_channels,
|
|
|
+ out_channels,
|
|
|
+ res2net_scale=8,
|
|
|
+ se_channels=128,
|
|
|
+ kernel_size=1,
|
|
|
+ dilation=1,
|
|
|
+ activation=torch.nn.ReLU,
|
|
|
+ groups=1,
|
|
|
+ ):
|
|
|
+ super().__init__()
|
|
|
+ self.out_channels = out_channels
|
|
|
+ self.tdnn1 = TDNNBlock(
|
|
|
+ in_channels,
|
|
|
+ out_channels,
|
|
|
+ kernel_size=1,
|
|
|
+ dilation=1,
|
|
|
+ activation=activation,
|
|
|
+ groups=groups,
|
|
|
+ )
|
|
|
+ self.res2net_block = Res2NetBlock(
|
|
|
+ out_channels, out_channels, res2net_scale, kernel_size, dilation
|
|
|
+ )
|
|
|
+ self.tdnn2 = TDNNBlock(
|
|
|
+ out_channels,
|
|
|
+ out_channels,
|
|
|
+ kernel_size=1,
|
|
|
+ dilation=1,
|
|
|
+ activation=activation,
|
|
|
+ groups=groups,
|
|
|
+ )
|
|
|
+ self.se_block = SEBlock(out_channels, se_channels, out_channels)
|
|
|
+
|
|
|
+ self.shortcut = None
|
|
|
+ if in_channels != out_channels:
|
|
|
+ self.shortcut = Conv1d(
|
|
|
+ in_channels=in_channels,
|
|
|
+ out_channels=out_channels,
|
|
|
+ kernel_size=1,
|
|
|
+ )
|
|
|
+
|
|
|
+ def forward(self, x, lengths=None):
|
|
|
+ residual = x
|
|
|
+ if self.shortcut:
|
|
|
+ residual = self.shortcut(x)
|
|
|
+
|
|
|
+ x = self.tdnn1(x)
|
|
|
+ x = self.res2net_block(x)
|
|
|
+ x = self.tdnn2(x)
|
|
|
+ x = self.se_block(x, lengths)
|
|
|
+
|
|
|
+ return x + residual
|
|
|
+
|
|
|
+
|
|
|
+class ECAPA_TDNN(torch.nn.Module):
|
|
|
+ """An implementation of the speaker embedding model in a paper.
|
|
|
+ "ECAPA-TDNN: Emphasized Channel Attention, Propagation and Aggregation in
|
|
|
+ TDNN Based Speaker Verification" (https://arxiv.org/abs/2005.07143).
|
|
|
+
|
|
|
+ Arguments
|
|
|
+ ---------
|
|
|
+ device : str
|
|
|
+ Device used, e.g., "cpu" or "cuda".
|
|
|
+ activation : torch class
|
|
|
+ A class for constructing the activation layers.
|
|
|
+ channels : list of ints
|
|
|
+ Output channels for TDNN/SERes2Net layer.
|
|
|
+ kernel_sizes : list of ints
|
|
|
+ List of kernel sizes for each layer.
|
|
|
+ dilations : list of ints
|
|
|
+ List of dilations for kernels in each layer.
|
|
|
+ lin_neurons : int
|
|
|
+ Number of neurons in linear layers.
|
|
|
+ groups : list of ints
|
|
|
+ List of groups for kernels in each layer.
|
|
|
+
|
|
|
+ Example
|
|
|
+ -------
|
|
|
+ >>> input_feats = torch.rand([5, 120, 80])
|
|
|
+ >>> compute_embedding = ECAPA_TDNN(80, lin_neurons=192)
|
|
|
+ >>> outputs = compute_embedding(input_feats)
|
|
|
+ >>> outputs.shape
|
|
|
+ torch.Size([5, 1, 192])
|
|
|
+ """
|
|
|
+
|
|
|
+ def __init__(
|
|
|
+ self,
|
|
|
+ input_size,
|
|
|
+ device="cpu",
|
|
|
+ lin_neurons=192,
|
|
|
+ activation=torch.nn.ReLU,
|
|
|
+ channels=[512, 512, 512, 512, 1536],
|
|
|
+ kernel_sizes=[5, 3, 3, 3, 1],
|
|
|
+ dilations=[1, 2, 3, 4, 1],
|
|
|
+ attention_channels=128,
|
|
|
+ res2net_scale=8,
|
|
|
+ se_channels=128,
|
|
|
+ global_context=True,
|
|
|
+ groups=[1, 1, 1, 1, 1],
|
|
|
+ window_size=20,
|
|
|
+ window_shift=1,
|
|
|
+ ):
|
|
|
+
|
|
|
+ super().__init__()
|
|
|
+ assert len(channels) == len(kernel_sizes)
|
|
|
+ assert len(channels) == len(dilations)
|
|
|
+ self.channels = channels
|
|
|
+ self.blocks = nn.ModuleList()
|
|
|
+ self.window_size = window_size
|
|
|
+ self.window_shift = window_shift
|
|
|
+
|
|
|
+ # The initial TDNN layer
|
|
|
+ self.blocks.append(
|
|
|
+ TDNNBlock(
|
|
|
+ input_size,
|
|
|
+ channels[0],
|
|
|
+ kernel_sizes[0],
|
|
|
+ dilations[0],
|
|
|
+ activation,
|
|
|
+ groups[0],
|
|
|
+ )
|
|
|
+ )
|
|
|
+
|
|
|
+ # SE-Res2Net layers
|
|
|
+ for i in range(1, len(channels) - 1):
|
|
|
+ self.blocks.append(
|
|
|
+ SERes2NetBlock(
|
|
|
+ channels[i - 1],
|
|
|
+ channels[i],
|
|
|
+ res2net_scale=res2net_scale,
|
|
|
+ se_channels=se_channels,
|
|
|
+ kernel_size=kernel_sizes[i],
|
|
|
+ dilation=dilations[i],
|
|
|
+ activation=activation,
|
|
|
+ groups=groups[i],
|
|
|
+ )
|
|
|
+ )
|
|
|
+
|
|
|
+ # Multi-layer feature aggregation
|
|
|
+ self.mfa = TDNNBlock(
|
|
|
+ channels[-1],
|
|
|
+ channels[-1],
|
|
|
+ kernel_sizes[-1],
|
|
|
+ dilations[-1],
|
|
|
+ activation,
|
|
|
+ groups=groups[-1],
|
|
|
+ )
|
|
|
+
|
|
|
+ # Attentive Statistical Pooling
|
|
|
+ self.asp = AttentiveStatisticsPooling(
|
|
|
+ channels[-1],
|
|
|
+ attention_channels=attention_channels,
|
|
|
+ global_context=global_context,
|
|
|
+ )
|
|
|
+ self.asp_bn = BatchNorm1d(input_size=channels[-1] * 2)
|
|
|
+
|
|
|
+ # Final linear transformation
|
|
|
+ self.fc = Conv1d(
|
|
|
+ in_channels=channels[-1] * 2,
|
|
|
+ out_channels=lin_neurons,
|
|
|
+ kernel_size=1,
|
|
|
+ )
|
|
|
+
|
|
|
+ def windowed_pooling(self, x, lengths=None):
|
|
|
+ # x: Batch, Channel, Time
|
|
|
+ tt = x.shape[2]
|
|
|
+ num_chunk = int(math.ceil(tt / self.window_shift))
|
|
|
+ pad = self.window_size // 2
|
|
|
+ x = F.pad(x, (pad, pad, 0, 0), "reflect")
|
|
|
+ stat_list = []
|
|
|
+
|
|
|
+ for i in range(num_chunk):
|
|
|
+ # B x C
|
|
|
+ st, ed = i * self.window_shift, i * self.window_shift + self.window_size
|
|
|
+ x = self.asp(x[:, :, st: ed],
|
|
|
+ lengths=torch.clamp(lengths - i, 0, self.window_size)
|
|
|
+ if lengths is not None else None)
|
|
|
+ x = self.asp_bn(x)
|
|
|
+ x = self.fc(x)
|
|
|
+ stat_list.append(x)
|
|
|
+
|
|
|
+ return torch.cat(stat_list, dim=2)
|
|
|
+
|
|
|
+ def forward(self, x, lengths=None):
|
|
|
+ """Returns the embedding vector.
|
|
|
+
|
|
|
+ Arguments
|
|
|
+ ---------
|
|
|
+ x : torch.Tensor
|
|
|
+ Tensor of shape (batch, time, channel).
|
|
|
+ lengths: torch.Tensor
|
|
|
+ Tensor of shape (batch, )
|
|
|
+ """
|
|
|
+ # Minimize transpose for efficiency
|
|
|
+ x = x.transpose(1, 2)
|
|
|
+
|
|
|
+ xl = []
|
|
|
+ for layer in self.blocks:
|
|
|
+ try:
|
|
|
+ x = layer(x, lengths=lengths)
|
|
|
+ except TypeError:
|
|
|
+ x = layer(x)
|
|
|
+ xl.append(x)
|
|
|
+
|
|
|
+ # Multi-layer feature aggregation
|
|
|
+ x = torch.cat(xl[1:], dim=1)
|
|
|
+ x = self.mfa(x)
|
|
|
+
|
|
|
+ if self.window_size is None:
|
|
|
+ # Attentive Statistical Pooling
|
|
|
+ x = self.asp(x, lengths=lengths)
|
|
|
+ x = self.asp_bn(x)
|
|
|
+ # Final linear transformation
|
|
|
+ x = self.fc(x)
|
|
|
+ # x = x.transpose(1, 2)
|
|
|
+ x = x.squeeze(2) # -> B, C
|
|
|
+ else:
|
|
|
+ x = self.windowed_pooling(x, lengths)
|
|
|
+ x = x.transpose(1, 2) # -> B, T, C
|
|
|
+ return x
|