MockingBird/synthesizer/models/tacotron.py

299 lines
14 KiB
Python

import torch
import torch.nn as nn
from .sublayer.global_style_token import GlobalStyleToken
from .sublayer.pre_net import PreNet
from .sublayer.cbhg import CBHG
from .sublayer.lsa import LSA
from .base import Base
from synthesizer.gst_hyperparameters import GSTHyperparameters as gst_hp
from synthesizer.hparams import hparams
class Encoder(nn.Module):
def __init__(self, num_chars, embed_dims=512, encoder_dims=256, K=5, num_highways=4, dropout=0.5):
""" Encoder for SV2TTS
Args:
num_chars (int): length of symbols
embed_dims (int, optional): embedding dim for input texts. Defaults to 512.
encoder_dims (int, optional): output dim for encoder. Defaults to 256.
K (int, optional): _description_. Defaults to 5.
num_highways (int, optional): _description_. Defaults to 4.
dropout (float, optional): _description_. Defaults to 0.5.
"""
super().__init__()
self.embedding = nn.Embedding(num_chars, embed_dims)
self.pre_net = PreNet(embed_dims, fc1_dims=encoder_dims, fc2_dims=encoder_dims,
dropout=dropout)
self.cbhg = CBHG(K=K, in_channels=encoder_dims, channels=encoder_dims,
proj_channels=[encoder_dims, encoder_dims],
num_highways=num_highways)
def forward(self, x):
"""forward pass for encoder
Args:
x (2D tensor with size `[batch_size, text_num_chars]`): input texts list
Returns:
3D tensor with size `[batch_size, text_num_chars, encoder_dims]`
"""
x = self.embedding(x) # return: [batch_size, text_num_chars, tts_embed_dims]
x = self.pre_net(x) # return: [batch_size, text_num_chars, encoder_dims]
x.transpose_(1, 2) # return: [batch_size, encoder_dims, text_num_chars]
return self.cbhg(x) # return: [batch_size, text_num_chars, encoder_dims]
class Decoder(nn.Module):
# Class variable because its value doesn't change between classes
# yet ought to be scoped by class because its a property of a Decoder
max_r = 20
def __init__(self, n_mels, input_dims, decoder_dims, lstm_dims,
dropout, speaker_embedding_size):
super().__init__()
self.register_buffer("r", torch.tensor(1, dtype=torch.int))
self.n_mels = n_mels
self.prenet = PreNet(n_mels, fc1_dims=decoder_dims * 2, fc2_dims=decoder_dims * 2,
dropout=dropout)
self.attn_net = LSA(decoder_dims)
if hparams.use_gst:
speaker_embedding_size += gst_hp.E
self.attn_rnn = nn.GRUCell(input_dims + decoder_dims * 2, decoder_dims)
self.rnn_input = nn.Linear(input_dims + decoder_dims, lstm_dims)
self.res_rnn1 = nn.LSTMCell(lstm_dims, lstm_dims)
self.res_rnn2 = nn.LSTMCell(lstm_dims, lstm_dims)
self.mel_proj = nn.Linear(lstm_dims, n_mels * self.max_r, bias=False)
self.stop_proj = nn.Linear(input_dims + lstm_dims, 1)
def zoneout(self, prev, current, device, p=0.1):
mask = torch.zeros(prev.size(),device=device).bernoulli_(p)
return prev * mask + current * (1 - mask)
def forward(self, encoder_seq, encoder_seq_proj, prenet_in,
hidden_states, cell_states, context_vec, times, chars):
"""_summary_
Args:
encoder_seq (3D tensor `[batch_size, text_num_chars, project_dim(default to 512)]`): _description_
encoder_seq_proj (3D tensor `[batch_size, text_num_chars, decoder_dims(default to 128)]`): _description_
prenet_in (2D tensor `[batch_size, n_mels]`): _description_
hidden_states (_type_): _description_
cell_states (_type_): _description_
context_vec (2D tensor `[batch_size, project_dim(default to 512)]`): _description_
times (int): the number of times runned
chars (2D tensor with size `[batch_size, text_num_chars]`): original texts list input
"""
# Need this for reshaping mels
batch_size = encoder_seq.size(0)
device = encoder_seq.device
# Unpack the hidden and cell states
attn_hidden, rnn1_hidden, rnn2_hidden = hidden_states
rnn1_cell, rnn2_cell = cell_states
# PreNet for the Attention RNN
prenet_out = self.prenet(prenet_in) # return: `[batch_size, decoder_dims * 2(256)]`
# Compute the Attention RNN hidden state
attn_rnn_in = torch.cat([context_vec, prenet_out], dim=-1) # `[batch_size, project_dim + decoder_dims * 2 (768)]`
attn_hidden = self.attn_rnn(attn_rnn_in.squeeze(1), attn_hidden) # `[batch_size, decoder_dims (128)]`
# Compute the attention scores
scores = self.attn_net(encoder_seq_proj, attn_hidden, times, chars)
# Dot product to create the context vector
context_vec = scores @ encoder_seq
context_vec = context_vec.squeeze(1)
# Concat Attention RNN output w. Context Vector & project
x = torch.cat([context_vec, attn_hidden], dim=1) # `[batch_size, project_dim + decoder_dims (630)]`
x = self.rnn_input(x) # `[batch_size, lstm_dims(1024)]`
# Compute first Residual RNN, training with fixed zoneout rate 0.1
rnn1_hidden_next, rnn1_cell = self.res_rnn1(x, (rnn1_hidden, rnn1_cell)) # `[batch_size, lstm_dims(1024)]`
if self.training:
rnn1_hidden = self.zoneout(rnn1_hidden, rnn1_hidden_next,device=device)
else:
rnn1_hidden = rnn1_hidden_next
x = x + rnn1_hidden
# Compute second Residual RNN
rnn2_hidden_next, rnn2_cell = self.res_rnn2(x, (rnn2_hidden, rnn2_cell)) # `[batch_size, lstm_dims(1024)]`
if self.training:
rnn2_hidden = self.zoneout(rnn2_hidden, rnn2_hidden_next, device=device)
else:
rnn2_hidden = rnn2_hidden_next
x = x + rnn2_hidden
# Project Mels
mels = self.mel_proj(x) # `[batch_size, 1600]`
mels = mels.view(batch_size, self.n_mels, self.max_r)[:, :, :self.r] # `[batch_size, n_mels, r]`
hidden_states = (attn_hidden, rnn1_hidden, rnn2_hidden)
cell_states = (rnn1_cell, rnn2_cell)
# Stop token prediction
s = torch.cat((x, context_vec), dim=1)
s = self.stop_proj(s)
stop_tokens = torch.sigmoid(s)
return mels, scores, hidden_states, cell_states, context_vec, stop_tokens
class Tacotron(Base):
def __init__(self, embed_dims, num_chars, encoder_dims, decoder_dims, n_mels,
fft_bins, postnet_dims, encoder_K, lstm_dims, postnet_K, num_highways,
dropout, stop_threshold, speaker_embedding_size):
super().__init__(stop_threshold)
self.n_mels = n_mels
self.lstm_dims = lstm_dims
self.encoder_dims = encoder_dims
self.decoder_dims = decoder_dims
self.speaker_embedding_size = speaker_embedding_size
self.encoder = Encoder(num_chars, embed_dims, encoder_dims,
encoder_K, num_highways, dropout)
self.project_dims = encoder_dims + speaker_embedding_size
if hparams.use_gst:
self.project_dims += gst_hp.E
self.encoder_proj = nn.Linear(self.project_dims, decoder_dims, bias=False)
if hparams.use_gst:
self.gst = GlobalStyleToken(speaker_embedding_size)
self.decoder = Decoder(n_mels, self.project_dims, decoder_dims, lstm_dims,
dropout, speaker_embedding_size)
self.postnet = CBHG(postnet_K, n_mels, postnet_dims,
[postnet_dims, fft_bins], num_highways)
self.post_proj = nn.Linear(postnet_dims, fft_bins, bias=False)
@staticmethod
def _concat_speaker_embedding(outputs, speaker_embeddings):
speaker_embeddings_ = speaker_embeddings.expand(
outputs.size(0), outputs.size(1), -1)
outputs = torch.cat([outputs, speaker_embeddings_], dim=-1)
return outputs
@staticmethod
def _add_speaker_embedding(x, speaker_embedding):
"""Add speaker embedding
This concats the speaker embedding for each char in the encoder output
Args:
x (3D tensor with size `[batch_size, text_num_chars, encoder_dims]`): the encoder output
speaker_embedding (2D tensor `[batch_size, speaker_embedding_size]`): the speaker embedding
Returns:
3D tensor with size `[batch_size, text_num_chars, encoder_dims+speaker_embedding_size]`
"""
# Save the dimensions as human-readable names
batch_size = x.size()[0]
text_num_chars = x.size()[1]
# Start by making a copy of each speaker embedding to match the input text length
# The output of this has size (batch_size, text_num_chars * speaker_embedding_size)
speaker_embedding_size = speaker_embedding.size()[1]
e = speaker_embedding.repeat_interleave(text_num_chars, dim=1)
# Reshape it and transpose
e = e.reshape(batch_size, speaker_embedding_size, text_num_chars)
e = e.transpose(1, 2)
# Concatenate the tiled speaker embedding with the encoder output
x = torch.cat((x, e), 2)
return x
def forward(self, texts, mels, speaker_embedding, steps=2000, style_idx=0, min_stop_token=5):
"""Forward pass for Tacotron
Args:
texts (`[batch_size, text_num_chars]`): input texts list
mels (`[batch_size, varied_mel_lengths, steps]`): mels for comparison (training only)
speaker_embedding (`[batch_size, speaker_embedding_size(default to 256)]`): referring embedding.
steps (int, optional): . Defaults to 2000.
style_idx (int, optional): GST style selected. Defaults to 0.
min_stop_token (int, optional): decoder min_stop_token. Defaults to 5.
"""
device = texts.device # use same device as parameters
if self.training:
self.step += 1
batch_size, _, steps = mels.size()
else:
batch_size, _ = texts.size()
# Initialise all hidden states and pack into tuple
attn_hidden = torch.zeros(batch_size, self.decoder_dims, device=device)
rnn1_hidden = torch.zeros(batch_size, self.lstm_dims, device=device)
rnn2_hidden = torch.zeros(batch_size, self.lstm_dims, device=device)
hidden_states = (attn_hidden, rnn1_hidden, rnn2_hidden)
# Initialise all lstm cell states and pack into tuple
rnn1_cell = torch.zeros(batch_size, self.lstm_dims, device=device)
rnn2_cell = torch.zeros(batch_size, self.lstm_dims, device=device)
cell_states = (rnn1_cell, rnn2_cell)
# <GO> Frame for start of decoder loop
go_frame = torch.zeros(batch_size, self.n_mels, device=device)
# SV2TTS: Run the encoder with the speaker embedding
# The projection avoids unnecessary matmuls in the decoder loop
encoder_seq = self.encoder(texts)
encoder_seq = self._add_speaker_embedding(encoder_seq, speaker_embedding)
if hparams.use_gst and self.gst is not None:
if self.training:
style_embed = self.gst(speaker_embedding, speaker_embedding) # for training, speaker embedding can represent both style inputs and referenced
# style_embed = style_embed.expand_as(encoder_seq)
# encoder_seq = torch.cat((encoder_seq, style_embed), 2)
elif style_idx >= 0 and style_idx < 10:
query = torch.zeros(1, 1, self.gst.stl.attention.num_units)
if device.type == 'cuda':
query = query.cuda()
gst_embed = torch.tanh(self.gst.stl.embed)
key = gst_embed[style_idx].unsqueeze(0).expand(1, -1, -1)
style_embed = self.gst.stl.attention(query, key)
else:
speaker_embedding_style = torch.zeros(speaker_embedding.size()[0], 1, self.speaker_embedding_size).to(device)
style_embed = self.gst(speaker_embedding_style, speaker_embedding)
encoder_seq = self._concat_speaker_embedding(encoder_seq, style_embed) # return: [batch_size, text_num_chars, project_dims]
encoder_seq_proj = self.encoder_proj(encoder_seq) # return: [batch_size, text_num_chars, decoder_dims]
# Need a couple of lists for outputs
mel_outputs, attn_scores, stop_outputs = [], [], []
# Need an initial context vector
context_vec = torch.zeros(batch_size, self.project_dims, device=device)
# Run the decoder loop
for t in range(0, steps, self.r):
if self.training:
prenet_in = mels[:, :, t -1] if t > 0 else go_frame
else:
prenet_in = mel_outputs[-1][:, :, -1] if t > 0 else go_frame
mel_frames, scores, hidden_states, cell_states, context_vec, stop_tokens = \
self.decoder(encoder_seq, encoder_seq_proj, prenet_in,
hidden_states, cell_states, context_vec, t, texts)
mel_outputs.append(mel_frames)
attn_scores.append(scores)
stop_outputs.extend([stop_tokens] * self.r)
if not self.training and (stop_tokens * 10 > min_stop_token).all() and t > 10: break
# Concat the mel outputs into sequence
mel_outputs = torch.cat(mel_outputs, dim=2)
# Post-Process for Linear Spectrograms
postnet_out = self.postnet(mel_outputs)
linear = self.post_proj(postnet_out)
linear = linear.transpose(1, 2)
# For easy visualisation
attn_scores = torch.cat(attn_scores, 1)
# attn_scores = attn_scores.cpu().data.numpy()
stop_outputs = torch.cat(stop_outputs, 1)
if self.training:
self.train()
return mel_outputs, linear, attn_scores, stop_outputs
def generate(self, x, speaker_embedding, steps=2000, style_idx=0, min_stop_token=5):
self.eval()
mel_outputs, linear, attn_scores, _ = self.forward(x, None, speaker_embedding, steps, style_idx, min_stop_token)
return mel_outputs, linear, attn_scores