# Copyright 2020 Nagoya University (Tomoki Hayashi)
# Apache 2.0 (http://www.apache.org/licenses/LICENSE-2.0)
"""Fastspeech related modules for ESPnet2."""
import logging
from typing import Dict, Optional, Sequence, Tuple
import torch
import torch.nn.functional as F
from typeguard import check_argument_types
from espnet2.torch_utils.device_funcs import force_gatherable
from espnet2.torch_utils.initialize import initialize
from espnet2.tts.abs_tts import AbsTTS
from espnet2.tts.gst.style_encoder import StyleEncoder
from espnet.nets.pytorch_backend.conformer.encoder import Encoder as ConformerEncoder
from espnet.nets.pytorch_backend.e2e_tts_fastspeech import (
FeedForwardTransformerLoss as FastSpeechLoss,
)
from espnet.nets.pytorch_backend.fastspeech.duration_predictor import DurationPredictor
from espnet.nets.pytorch_backend.fastspeech.length_regulator import LengthRegulator
from espnet.nets.pytorch_backend.nets_utils import make_non_pad_mask, make_pad_mask
from espnet.nets.pytorch_backend.tacotron2.decoder import Postnet
from espnet.nets.pytorch_backend.transformer.embedding import (
PositionalEncoding,
ScaledPositionalEncoding,
)
from espnet.nets.pytorch_backend.transformer.encoder import (
Encoder as TransformerEncoder,
)
[docs]class FastSpeech(AbsTTS):
"""FastSpeech module for end-to-end text-to-speech.
This is a module of FastSpeech, feed-forward Transformer with duration predictor
described in `FastSpeech: Fast, Robust and Controllable Text to Speech`_, which
does not require any auto-regressive processing during inference, resulting in
fast decoding compared with auto-regressive Transformer.
.. _`FastSpeech: Fast, Robust and Controllable Text to Speech`:
https://arxiv.org/pdf/1905.09263.pdf
"""
def __init__(
self,
# network structure related
idim: int,
odim: int,
adim: int = 384,
aheads: int = 4,
elayers: int = 6,
eunits: int = 1536,
dlayers: int = 6,
dunits: int = 1536,
postnet_layers: int = 5,
postnet_chans: int = 512,
postnet_filts: int = 5,
postnet_dropout_rate: float = 0.5,
positionwise_layer_type: str = "conv1d",
positionwise_conv_kernel_size: int = 1,
use_scaled_pos_enc: bool = True,
use_batch_norm: bool = True,
encoder_normalize_before: bool = True,
decoder_normalize_before: bool = True,
encoder_concat_after: bool = False,
decoder_concat_after: bool = False,
duration_predictor_layers: int = 2,
duration_predictor_chans: int = 384,
duration_predictor_kernel_size: int = 3,
duration_predictor_dropout_rate: float = 0.1,
reduction_factor: int = 1,
encoder_type: str = "transformer",
decoder_type: str = "transformer",
transformer_enc_dropout_rate: float = 0.1,
transformer_enc_positional_dropout_rate: float = 0.1,
transformer_enc_attn_dropout_rate: float = 0.1,
transformer_dec_dropout_rate: float = 0.1,
transformer_dec_positional_dropout_rate: float = 0.1,
transformer_dec_attn_dropout_rate: float = 0.1,
# only for conformer
conformer_rel_pos_type: str = "legacy",
conformer_pos_enc_layer_type: str = "rel_pos",
conformer_self_attn_layer_type: str = "rel_selfattn",
conformer_activation_type: str = "swish",
use_macaron_style_in_conformer: bool = True,
use_cnn_in_conformer: bool = True,
conformer_enc_kernel_size: int = 7,
conformer_dec_kernel_size: int = 31,
zero_triu: bool = False,
# extra embedding related
spks: Optional[int] = None,
langs: Optional[int] = None,
spk_embed_dim: Optional[int] = None,
spk_embed_integration_type: str = "add",
use_gst: bool = False,
gst_tokens: int = 10,
gst_heads: int = 4,
gst_conv_layers: int = 6,
gst_conv_chans_list: Sequence[int] = (32, 32, 64, 64, 128, 128),
gst_conv_kernel_size: int = 3,
gst_conv_stride: int = 2,
gst_gru_layers: int = 1,
gst_gru_units: int = 128,
# training related
init_type: str = "xavier_uniform",
init_enc_alpha: float = 1.0,
init_dec_alpha: float = 1.0,
use_masking: bool = False,
use_weighted_masking: bool = False,
):
"""Initialize FastSpeech module.
Args:
idim (int): Dimension of the inputs.
odim (int): Dimension of the outputs.
elayers (int): Number of encoder layers.
eunits (int): Number of encoder hidden units.
dlayers (int): Number of decoder layers.
dunits (int): Number of decoder hidden units.
postnet_layers (int): Number of postnet layers.
postnet_chans (int): Number of postnet channels.
postnet_filts (int): Kernel size of postnet.
postnet_dropout_rate (float): Dropout rate in postnet.
use_scaled_pos_enc (bool): Whether to use trainable scaled pos encoding.
use_batch_norm (bool): Whether to use batch normalization in encoder prenet.
encoder_normalize_before (bool): Whether to apply layernorm layer before
encoder block.
decoder_normalize_before (bool): Whether to apply layernorm layer before
decoder block.
encoder_concat_after (bool): Whether to concatenate attention layer's input
and output in encoder.
decoder_concat_after (bool): Whether to concatenate attention layer's input
and output in decoder.
duration_predictor_layers (int): Number of duration predictor layers.
duration_predictor_chans (int): Number of duration predictor channels.
duration_predictor_kernel_size (int): Kernel size of duration predictor.
duration_predictor_dropout_rate (float): Dropout rate in duration predictor.
reduction_factor (int): Reduction factor.
encoder_type (str): Encoder type ("transformer" or "conformer").
decoder_type (str): Decoder type ("transformer" or "conformer").
transformer_enc_dropout_rate (float): Dropout rate in encoder except
attention and positional encoding.
transformer_enc_positional_dropout_rate (float): Dropout rate after encoder
positional encoding.
transformer_enc_attn_dropout_rate (float): Dropout rate in encoder
self-attention module.
transformer_dec_dropout_rate (float): Dropout rate in decoder except
attention & positional encoding.
transformer_dec_positional_dropout_rate (float): Dropout rate after decoder
positional encoding.
transformer_dec_attn_dropout_rate (float): Dropout rate in decoder
self-attention module.
conformer_rel_pos_type (str): Relative pos encoding type in conformer.
conformer_pos_enc_layer_type (str): Pos encoding layer type in conformer.
conformer_self_attn_layer_type (str): Self-attention layer type in conformer
conformer_activation_type (str): Activation function type in conformer.
use_macaron_style_in_conformer: Whether to use macaron style FFN.
use_cnn_in_conformer: Whether to use CNN in conformer.
conformer_enc_kernel_size: Kernel size of encoder conformer.
conformer_dec_kernel_size: Kernel size of decoder conformer.
zero_triu: Whether to use zero triu in relative self-attention module.
spks (Optional[int]): Number of speakers. If set to > 1, assume that the
sids will be provided as the input and use sid embedding layer.
langs (Optional[int]): Number of languages. If set to > 1, assume that the
lids will be provided as the input and use sid embedding layer.
spk_embed_dim (Optional[int]): Speaker embedding dimension. If set to > 0,
assume that spembs will be provided as the input.
spk_embed_integration_type: How to integrate speaker embedding.
use_gst (str): Whether to use global style token.
gst_tokens (int): The number of GST embeddings.
gst_heads (int): The number of heads in GST multihead attention.
gst_conv_layers (int): The number of conv layers in GST.
gst_conv_chans_list: (Sequence[int]):
List of the number of channels of conv layers in GST.
gst_conv_kernel_size (int): Kernel size of conv layers in GST.
gst_conv_stride (int): Stride size of conv layers in GST.
gst_gru_layers (int): The number of GRU layers in GST.
gst_gru_units (int): The number of GRU units in GST.
init_type (str): How to initialize transformer parameters.
init_enc_alpha (float): Initial value of alpha in scaled pos encoding of the
encoder.
init_dec_alpha (float): Initial value of alpha in scaled pos encoding of the
decoder.
use_masking (bool): Whether to apply masking for padded part in loss
calculation.
use_weighted_masking (bool): Whether to apply weighted masking in loss
calculation.
"""
assert check_argument_types()
super().__init__()
# store hyperparameters
self.idim = idim
self.odim = odim
self.eos = idim - 1
self.reduction_factor = reduction_factor
self.encoder_type = encoder_type
self.decoder_type = decoder_type
self.use_scaled_pos_enc = use_scaled_pos_enc
self.use_gst = use_gst
# use idx 0 as padding idx
self.padding_idx = 0
# get positional encoding class
pos_enc_class = (
ScaledPositionalEncoding if self.use_scaled_pos_enc else PositionalEncoding
)
# check relative positional encoding compatibility
if "conformer" in [encoder_type, decoder_type]:
if conformer_rel_pos_type == "legacy":
if conformer_pos_enc_layer_type == "rel_pos":
conformer_pos_enc_layer_type = "legacy_rel_pos"
logging.warning(
"Fallback to conformer_pos_enc_layer_type = 'legacy_rel_pos' "
"due to the compatibility. If you want to use the new one, "
"please use conformer_pos_enc_layer_type = 'latest'."
)
if conformer_self_attn_layer_type == "rel_selfattn":
conformer_self_attn_layer_type = "legacy_rel_selfattn"
logging.warning(
"Fallback to "
"conformer_self_attn_layer_type = 'legacy_rel_selfattn' "
"due to the compatibility. If you want to use the new one, "
"please use conformer_pos_enc_layer_type = 'latest'."
)
elif conformer_rel_pos_type == "latest":
assert conformer_pos_enc_layer_type != "legacy_rel_pos"
assert conformer_self_attn_layer_type != "legacy_rel_selfattn"
else:
raise ValueError(f"Unknown rel_pos_type: {conformer_rel_pos_type}")
# define encoder
encoder_input_layer = torch.nn.Embedding(
num_embeddings=idim, embedding_dim=adim, padding_idx=self.padding_idx
)
if encoder_type == "transformer":
self.encoder = TransformerEncoder(
idim=idim,
attention_dim=adim,
attention_heads=aheads,
linear_units=eunits,
num_blocks=elayers,
input_layer=encoder_input_layer,
dropout_rate=transformer_enc_dropout_rate,
positional_dropout_rate=transformer_enc_positional_dropout_rate,
attention_dropout_rate=transformer_enc_attn_dropout_rate,
pos_enc_class=pos_enc_class,
normalize_before=encoder_normalize_before,
concat_after=encoder_concat_after,
positionwise_layer_type=positionwise_layer_type,
positionwise_conv_kernel_size=positionwise_conv_kernel_size,
)
elif encoder_type == "conformer":
self.encoder = ConformerEncoder(
idim=idim,
attention_dim=adim,
attention_heads=aheads,
linear_units=eunits,
num_blocks=elayers,
input_layer=encoder_input_layer,
dropout_rate=transformer_enc_dropout_rate,
positional_dropout_rate=transformer_enc_positional_dropout_rate,
attention_dropout_rate=transformer_enc_attn_dropout_rate,
normalize_before=encoder_normalize_before,
concat_after=encoder_concat_after,
positionwise_layer_type=positionwise_layer_type,
positionwise_conv_kernel_size=positionwise_conv_kernel_size,
macaron_style=use_macaron_style_in_conformer,
pos_enc_layer_type=conformer_pos_enc_layer_type,
selfattention_layer_type=conformer_self_attn_layer_type,
activation_type=conformer_activation_type,
use_cnn_module=use_cnn_in_conformer,
cnn_module_kernel=conformer_enc_kernel_size,
)
else:
raise ValueError(f"{encoder_type} is not supported.")
# define GST
if self.use_gst:
self.gst = StyleEncoder(
idim=odim, # the input is mel-spectrogram
gst_tokens=gst_tokens,
gst_token_dim=adim,
gst_heads=gst_heads,
conv_layers=gst_conv_layers,
conv_chans_list=gst_conv_chans_list,
conv_kernel_size=gst_conv_kernel_size,
conv_stride=gst_conv_stride,
gru_layers=gst_gru_layers,
gru_units=gst_gru_units,
)
# define spk and lang embedding
self.spks = None
if spks is not None and spks > 1:
self.spks = spks
self.sid_emb = torch.nn.Embedding(spks, adim)
self.langs = None
if langs is not None and langs > 1:
self.langs = langs
self.lid_emb = torch.nn.Embedding(langs, adim)
# define additional projection for speaker embedding
self.spk_embed_dim = None
if spk_embed_dim is not None and spk_embed_dim > 0:
self.spk_embed_dim = spk_embed_dim
self.spk_embed_integration_type = spk_embed_integration_type
if self.spk_embed_dim is not None:
if self.spk_embed_integration_type == "add":
self.projection = torch.nn.Linear(self.spk_embed_dim, adim)
else:
self.projection = torch.nn.Linear(adim + self.spk_embed_dim, adim)
# define duration predictor
self.duration_predictor = DurationPredictor(
idim=adim,
n_layers=duration_predictor_layers,
n_chans=duration_predictor_chans,
kernel_size=duration_predictor_kernel_size,
dropout_rate=duration_predictor_dropout_rate,
)
# define length regulator
self.length_regulator = LengthRegulator()
# define decoder
# NOTE: we use encoder as decoder
# because fastspeech's decoder is the same as encoder
if decoder_type == "transformer":
self.decoder = TransformerEncoder(
idim=0,
attention_dim=adim,
attention_heads=aheads,
linear_units=dunits,
num_blocks=dlayers,
input_layer=None,
dropout_rate=transformer_dec_dropout_rate,
positional_dropout_rate=transformer_dec_positional_dropout_rate,
attention_dropout_rate=transformer_dec_attn_dropout_rate,
pos_enc_class=pos_enc_class,
normalize_before=decoder_normalize_before,
concat_after=decoder_concat_after,
positionwise_layer_type=positionwise_layer_type,
positionwise_conv_kernel_size=positionwise_conv_kernel_size,
)
elif decoder_type == "conformer":
self.decoder = ConformerEncoder(
idim=0,
attention_dim=adim,
attention_heads=aheads,
linear_units=dunits,
num_blocks=dlayers,
input_layer=None,
dropout_rate=transformer_dec_dropout_rate,
positional_dropout_rate=transformer_dec_positional_dropout_rate,
attention_dropout_rate=transformer_dec_attn_dropout_rate,
normalize_before=decoder_normalize_before,
concat_after=decoder_concat_after,
positionwise_layer_type=positionwise_layer_type,
positionwise_conv_kernel_size=positionwise_conv_kernel_size,
macaron_style=use_macaron_style_in_conformer,
pos_enc_layer_type=conformer_pos_enc_layer_type,
selfattention_layer_type=conformer_self_attn_layer_type,
activation_type=conformer_activation_type,
use_cnn_module=use_cnn_in_conformer,
cnn_module_kernel=conformer_dec_kernel_size,
)
else:
raise ValueError(f"{decoder_type} is not supported.")
# define final projection
self.feat_out = torch.nn.Linear(adim, odim * reduction_factor)
# define postnet
self.postnet = (
None
if postnet_layers == 0
else Postnet(
idim=idim,
odim=odim,
n_layers=postnet_layers,
n_chans=postnet_chans,
n_filts=postnet_filts,
use_batch_norm=use_batch_norm,
dropout_rate=postnet_dropout_rate,
)
)
# initialize parameters
self._reset_parameters(
init_type=init_type,
init_enc_alpha=init_enc_alpha,
init_dec_alpha=init_dec_alpha,
)
# define criterions
self.criterion = FastSpeechLoss(
use_masking=use_masking, use_weighted_masking=use_weighted_masking
)
def _forward(
self,
xs: torch.Tensor,
ilens: torch.Tensor,
ys: Optional[torch.Tensor] = None,
olens: Optional[torch.Tensor] = None,
ds: Optional[torch.Tensor] = None,
spembs: Optional[torch.Tensor] = None,
sids: Optional[torch.Tensor] = None,
lids: Optional[torch.Tensor] = None,
is_inference: bool = False,
alpha: float = 1.0,
) -> Sequence[torch.Tensor]:
# forward encoder
x_masks = self._source_mask(ilens)
hs, _ = self.encoder(xs, x_masks) # (B, T_text, adim)
# integrate with GST
if self.use_gst:
style_embs = self.gst(ys)
hs = hs + style_embs.unsqueeze(1)
# integrate with SID and LID embeddings
if self.spks is not None:
sid_embs = self.sid_emb(sids.view(-1))
hs = hs + sid_embs.unsqueeze(1)
if self.langs is not None:
lid_embs = self.lid_emb(lids.view(-1))
hs = hs + lid_embs.unsqueeze(1)
# integrate speaker embedding
if self.spk_embed_dim is not None:
hs = self._integrate_with_spk_embed(hs, spembs)
# forward duration predictor and length regulator
d_masks = make_pad_mask(ilens).to(xs.device)
if is_inference:
d_outs = self.duration_predictor.inference(hs, d_masks) # (B, T_text)
hs = self.length_regulator(hs, d_outs, alpha) # (B, T_feats, adim)
else:
d_outs = self.duration_predictor(hs, d_masks) # (B, T_text)
hs = self.length_regulator(hs, ds) # (B, T_feats, adim)
# forward decoder
if olens is not None and not is_inference:
if self.reduction_factor > 1:
olens_in = olens.new([olen // self.reduction_factor for olen in olens])
else:
olens_in = olens
h_masks = self._source_mask(olens_in)
else:
h_masks = None
zs, _ = self.decoder(hs, h_masks) # (B, T_feats, adim)
before_outs = self.feat_out(zs).view(
zs.size(0), -1, self.odim
) # (B, T_feats, odim)
# postnet -> (B, T_feats//r * r, odim)
if self.postnet is None:
after_outs = before_outs
else:
after_outs = before_outs + self.postnet(
before_outs.transpose(1, 2)
).transpose(1, 2)
return before_outs, after_outs, d_outs
[docs] def forward(
self,
text: torch.Tensor,
text_lengths: torch.Tensor,
feats: torch.Tensor,
feats_lengths: torch.Tensor,
durations: torch.Tensor,
durations_lengths: torch.Tensor,
spembs: Optional[torch.Tensor] = None,
sids: Optional[torch.Tensor] = None,
lids: Optional[torch.Tensor] = None,
joint_training: bool = False,
) -> Tuple[torch.Tensor, Dict[str, torch.Tensor], torch.Tensor]:
"""Calculate forward propagation.
Args:
text (LongTensor): Batch of padded character ids (B, T_text).
text_lengths (LongTensor): Batch of lengths of each input (B,).
feats (Tensor): Batch of padded target features (B, T_feats, odim).
feats_lengths (LongTensor): Batch of the lengths of each target (B,).
durations (LongTensor): Batch of padded durations (B, T_text + 1).
durations_lengths (LongTensor): Batch of duration lengths (B, T_text + 1).
spembs (Optional[Tensor]): Batch of speaker embeddings (B, spk_embed_dim).
sids (Optional[Tensor]): Batch of speaker IDs (B, 1).
lids (Optional[Tensor]): Batch of language IDs (B, 1).
joint_training (bool): Whether to perform joint training with vocoder.
Returns:
Tensor: Loss scalar value.
Dict: Statistics to be monitored.
Tensor: Weight value if not joint training else model outputs.
"""
text = text[:, : text_lengths.max()] # for data-parallel
feats = feats[:, : feats_lengths.max()] # for data-parallel
durations = durations[:, : durations_lengths.max()] # for data-parallel
batch_size = text.size(0)
# Add eos at the last of sequence
xs = F.pad(text, [0, 1], "constant", self.padding_idx)
for i, l in enumerate(text_lengths):
xs[i, l] = self.eos
ilens = text_lengths + 1
ys, ds = feats, durations
olens = feats_lengths
# forward propagation
before_outs, after_outs, d_outs = self._forward(
xs,
ilens,
ys,
olens,
ds,
spembs=spembs,
sids=sids,
lids=lids,
is_inference=False,
)
# modifiy mod part of groundtruth
if self.reduction_factor > 1:
olens = olens.new([olen - olen % self.reduction_factor for olen in olens])
max_olen = max(olens)
ys = ys[:, :max_olen]
# calculate loss
if self.postnet is None:
after_outs = None
l1_loss, duration_loss = self.criterion(
after_outs, before_outs, d_outs, ys, ds, ilens, olens
)
loss = l1_loss + duration_loss
stats = dict(
l1_loss=l1_loss.item(),
duration_loss=duration_loss.item(),
)
# report extra information
if self.encoder_type == "transformer" and self.use_scaled_pos_enc:
stats.update(
encoder_alpha=self.encoder.embed[-1].alpha.data.item(),
)
if self.decoder_type == "transformer" and self.use_scaled_pos_enc:
stats.update(
decoder_alpha=self.decoder.embed[-1].alpha.data.item(),
)
if not joint_training:
stats.update(loss=loss.item())
loss, stats, weight = force_gatherable(
(loss, stats, batch_size), loss.device
)
return loss, stats, weight
else:
return loss, stats, after_outs if after_outs is not None else before_outs
[docs] def inference(
self,
text: torch.Tensor,
feats: Optional[torch.Tensor] = None,
durations: Optional[torch.Tensor] = None,
spembs: Optional[torch.Tensor] = None,
sids: Optional[torch.Tensor] = None,
lids: Optional[torch.Tensor] = None,
alpha: float = 1.0,
use_teacher_forcing: bool = False,
) -> Dict[str, torch.Tensor]:
"""Generate the sequence of features given the sequences of characters.
Args:
text (LongTensor): Input sequence of characters (T_text,).
feats (Optional[Tensor]): Feature sequence to extract style (N, idim).
durations (Optional[LongTensor]): Groundtruth of duration (T_text + 1,).
spembs (Optional[Tensor]): Speaker embedding (spk_embed_dim,).
sids (Optional[Tensor]): Speaker ID (1,).
lids (Optional[Tensor]): Language ID (1,).
alpha (float): Alpha to control the speed.
use_teacher_forcing (bool): Whether to use teacher forcing.
If true, groundtruth of duration, pitch and energy will be used.
Returns:
Dict[str, Tensor]: Output dict including the following items:
* feat_gen (Tensor): Output sequence of features (T_feats, odim).
* duration (Tensor): Duration sequence (T_text + 1,).
"""
x, y = text, feats
spemb, d = spembs, durations
# add eos at the last of sequence
x = F.pad(x, [0, 1], "constant", self.eos)
# setup batch axis
ilens = torch.tensor([x.shape[0]], dtype=torch.long, device=x.device)
xs, ys = x.unsqueeze(0), None
if y is not None:
ys = y.unsqueeze(0)
if spemb is not None:
spembs = spemb.unsqueeze(0)
if use_teacher_forcing:
# use groundtruth of duration
ds = d.unsqueeze(0)
_, outs, d_outs = self._forward(
xs,
ilens,
ys,
ds=ds,
spembs=spembs,
sids=sids,
lids=lids,
) # (1, T_feats, odim)
else:
# inference
_, outs, d_outs = self._forward(
xs,
ilens,
ys,
spembs=spembs,
sids=sids,
lids=lids,
is_inference=True,
alpha=alpha,
) # (1, T_feats, odim)
return dict(feat_gen=outs[0], duration=d_outs[0])
def _integrate_with_spk_embed(
self, hs: torch.Tensor, spembs: torch.Tensor
) -> torch.Tensor:
"""Integrate speaker embedding with hidden states.
Args:
hs (Tensor): Batch of hidden state sequences (B, T_text, adim).
spembs (Tensor): Batch of speaker embeddings (B, spk_embed_dim).
Returns:
Tensor: Batch of integrated hidden state sequences (B, T_text, adim).
"""
if self.spk_embed_integration_type == "add":
# apply projection and then add to hidden states
spembs = self.projection(F.normalize(spembs))
hs = hs + spembs.unsqueeze(1)
elif self.spk_embed_integration_type == "concat":
# concat hidden states with spk embeds and then apply projection
spembs = F.normalize(spembs).unsqueeze(1).expand(-1, hs.size(1), -1)
hs = self.projection(torch.cat([hs, spembs], dim=-1))
else:
raise NotImplementedError("support only add or concat.")
return hs
def _source_mask(self, ilens: torch.Tensor) -> torch.Tensor:
"""Make masks for self-attention.
Args:
ilens (LongTensor): Batch of lengths (B,).
Returns:
Tensor: Mask tensor for self-attention.
dtype=torch.uint8 in PyTorch 1.2-
dtype=torch.bool in PyTorch 1.2+ (including 1.2)
Examples:
>>> ilens = [5, 3]
>>> self._source_mask(ilens)
tensor([[[1, 1, 1, 1, 1],
[1, 1, 1, 0, 0]]], dtype=torch.uint8)
"""
x_masks = make_non_pad_mask(ilens).to(next(self.parameters()).device)
return x_masks.unsqueeze(-2)
def _reset_parameters(
self, init_type: str, init_enc_alpha: float, init_dec_alpha: float
):
# initialize parameters
if init_type != "pytorch":
initialize(self, init_type)
# initialize alpha in scaled positional encoding
if self.encoder_type == "transformer" and self.use_scaled_pos_enc:
self.encoder.embed[-1].alpha.data = torch.tensor(init_enc_alpha)
if self.decoder_type == "transformer" and self.use_scaled_pos_enc:
self.decoder.embed[-1].alpha.data = torch.tensor(init_dec_alpha)