2025-06-16 09:45:34 +08:00

579 lines
20 KiB
Python

# Copyright 2024 Xiaomi Corp. (authors: Wei Kang
# Han Zhu)
#
# See ../../../../LICENSE for clarification regarding multiple authors
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from typing import List, Optional
import torch
import torch.nn as nn
from scaling import ScheduledFloat
from solver import EulerSolver
from torch.nn.parallel import DistributedDataParallel as DDP
from utils import (
AttributeDict,
condition_time_mask,
get_tokens_index,
make_pad_mask,
pad_labels,
prepare_avg_tokens_durations,
to_int_tuple,
)
from zipformer import TTSZipformer
def get_model(params: AttributeDict) -> nn.Module:
"""Get the normal TTS model."""
fm_decoder = get_fm_decoder_model(params)
text_encoder = get_text_encoder_model(params)
model = TtsModel(
fm_decoder=fm_decoder,
text_encoder=text_encoder,
text_embed_dim=params.text_embed_dim,
feat_dim=params.feat_dim,
vocab_size=params.vocab_size,
pad_id=params.pad_id,
)
return model
def get_distill_model(params: AttributeDict) -> nn.Module:
"""Get the distillation TTS model."""
fm_decoder = get_fm_decoder_model(params, distill=True)
text_encoder = get_text_encoder_model(params)
model = DistillTTSModelTrainWrapper(
fm_decoder=fm_decoder,
text_encoder=text_encoder,
text_embed_dim=params.text_embed_dim,
feat_dim=params.feat_dim,
vocab_size=params.vocab_size,
pad_id=params.pad_id,
)
return model
def get_fm_decoder_model(params: AttributeDict, distill: bool = False) -> nn.Module:
"""Get the Zipformer-based FM decoder model."""
encoder = TTSZipformer(
in_dim=params.feat_dim * 3,
out_dim=params.feat_dim,
downsampling_factor=to_int_tuple(params.fm_decoder_downsampling_factor),
num_encoder_layers=to_int_tuple(params.fm_decoder_num_layers),
cnn_module_kernel=to_int_tuple(params.fm_decoder_cnn_module_kernel),
encoder_dim=params.fm_decoder_dim,
feedforward_dim=params.fm_decoder_feedforward_dim,
num_heads=params.fm_decoder_num_heads,
query_head_dim=params.query_head_dim,
pos_head_dim=params.pos_head_dim,
value_head_dim=params.value_head_dim,
pos_dim=params.pos_dim,
dropout=ScheduledFloat((0.0, 0.3), (20000.0, 0.1)),
warmup_batches=4000.0,
use_time_embed=True,
time_embed_dim=192,
use_guidance_scale_embed=distill,
)
return encoder
def get_text_encoder_model(params: AttributeDict) -> nn.Module:
"""Get the Zipformer-based text encoder model."""
encoder = TTSZipformer(
in_dim=params.text_embed_dim,
out_dim=params.feat_dim,
downsampling_factor=to_int_tuple(params.text_encoder_downsampling_factor),
num_encoder_layers=to_int_tuple(params.text_encoder_num_layers),
cnn_module_kernel=to_int_tuple(params.text_encoder_cnn_module_kernel),
encoder_dim=params.text_encoder_dim,
feedforward_dim=params.text_encoder_feedforward_dim,
num_heads=params.text_encoder_num_heads,
query_head_dim=params.query_head_dim,
pos_head_dim=params.pos_head_dim,
value_head_dim=params.value_head_dim,
pos_dim=params.pos_dim,
dropout=ScheduledFloat((0.0, 0.3), (20000.0, 0.1)),
warmup_batches=4000.0,
use_time_embed=False,
)
return encoder
class TtsModel(nn.Module):
"""The normal TTS model."""
def __init__(
self,
fm_decoder: nn.Module,
text_encoder: nn.Module,
text_embed_dim: int,
feat_dim: int,
vocab_size: int,
pad_id: int = 0,
):
"""
Args:
fm_decoder: the flow-matching encoder model, inputs are the
input condition embeddings and noisy acoustic features,
outputs are better acoustic features.
text_encoder: the text encoder model. input are text
embeddings, output are contextualized text embeddings.
text_embed_dim: dimension of text embedding.
feat_dim: dimension of acoustic features.
vocab_size: vocabulary size.
pad_id: padding id.
"""
super().__init__()
self.feat_dim = feat_dim
self.text_embed_dim = text_embed_dim
self.pad_id = pad_id
self.fm_decoder = fm_decoder
self.text_encoder = text_encoder
self.embed = nn.Embedding(vocab_size, text_embed_dim)
self.distill = False
def forward_fm_decoder(
self,
t: torch.Tensor,
xt: torch.Tensor,
text_condition: torch.Tensor,
speech_condition: torch.Tensor,
padding_mask: Optional[torch.Tensor] = None,
guidance_scale: Optional[torch.Tensor] = None,
) -> torch.Tensor:
"""Compute velocity.
Args:
t: A tensor of shape (N, 1, 1) or a tensor of a float,
in the range of (0, 1).
xt: the input of the current timestep, including condition
embeddings and noisy acoustic features.
text_condition: the text condition embeddings, with the
shape (batch, seq_len, emb_dim).
speech_condition: the speech condition embeddings, with the
shape (batch, seq_len, emb_dim).
padding_mask: The mask for padding, True means masked
position, with the shape (N, T).
guidance_scale: The guidance scale in classifier-free guidance,
which is a tensor of shape (N, 1, 1) or a tensor of a float.
Returns:
predicted velocity, with the shape (batch, seq_len, emb_dim).
"""
assert t.dim() in (0, 3)
# Handle t with the shape (N, 1, 1):
# squeeze the last dimension if it's size is 1.
while t.dim() > 1 and t.size(-1) == 1:
t = t.squeeze(-1)
if guidance_scale is not None:
while guidance_scale.dim() > 1 and guidance_scale.size(-1) == 1:
guidance_scale = guidance_scale.squeeze(-1)
# Handle t with a single value: expand to the size of batch size.
if t.dim() == 0:
t = t.repeat(xt.shape[0])
if guidance_scale is not None and guidance_scale.dim() == 0:
guidance_scale = guidance_scale.repeat(xt.shape[0])
xt = torch.cat([xt, text_condition, speech_condition], dim=2)
vt = self.fm_decoder(
x=xt, t=t, padding_mask=padding_mask, guidance_scale=guidance_scale
)
return vt
def forward_text_embed(
self,
tokens: List[List[int]],
):
"""
Get the text embeddings.
Args:
tokens: a list of list of token ids.
Returns:
embed: the text embeddings, shape (batch, seq_len, emb_dim).
tokens_lens: the length of each token sequence, shape (batch,).
"""
device = (
self.device if isinstance(self, DDP) else next(self.parameters()).device
)
tokens_padded = pad_labels(tokens, pad_id=self.pad_id, device=device) # (B, S)
embed = self.embed(tokens_padded) # (B, S, C)
tokens_lens = torch.tensor(
[len(token) for token in tokens], dtype=torch.int64, device=device
)
tokens_padding_mask = make_pad_mask(tokens_lens, embed.shape[1]) # (B, S)
embed = self.text_encoder(
x=embed, t=None, padding_mask=tokens_padding_mask
) # (B, S, C)
return embed, tokens_lens
def forward_text_condition(
self,
embed: torch.Tensor,
tokens_lens: torch.Tensor,
features_lens: torch.Tensor,
):
"""
Get the text condition with the same length of the acoustic feature.
Args:
embed: the text embeddings, shape (batch, token_seq_len, emb_dim).
tokens_lens: the length of each token sequence, shape (batch,).
features_lens: the length of each acoustic feature sequence,
shape (batch,).
Returns:
text_condition: the text condition, shape
(batch, feature_seq_len, emb_dim).
padding_mask: the padding mask of text condition, shape
(batch, feature_seq_len).
"""
num_frames = int(features_lens.max())
padding_mask = make_pad_mask(features_lens, max_len=num_frames) # (B, T)
tokens_durations = prepare_avg_tokens_durations(features_lens, tokens_lens)
tokens_index = get_tokens_index(tokens_durations, num_frames).to(
embed.device
) # (B, T)
text_condition = torch.gather(
embed,
dim=1,
index=tokens_index.unsqueeze(-1).expand(
embed.size(0), num_frames, embed.size(-1)
),
) # (B, T, F)
return text_condition, padding_mask
def forward_text_train(
self,
tokens: List[List[int]],
features_lens: torch.Tensor,
):
"""
Process text for training, given text tokens and real feature lengths.
"""
embed, tokens_lens = self.forward_text_embed(tokens)
text_condition, padding_mask = self.forward_text_condition(
embed, tokens_lens, features_lens
)
return (
text_condition,
padding_mask,
)
def forward_text_inference_gt_duration(
self,
tokens: List[List[int]],
features_lens: torch.Tensor,
prompt_tokens: List[List[int]],
prompt_features_lens: torch.Tensor,
):
"""
Process text for inference, given text tokens, real feature lengths and prompts.
"""
tokens = [
prompt_token + token for prompt_token, token in zip(prompt_tokens, tokens)
]
features_lens = prompt_features_lens + features_lens
embed, tokens_lens = self.forward_text_embed(tokens)
text_condition, padding_mask = self.forward_text_condition(
embed, tokens_lens, features_lens
)
return text_condition, padding_mask
def forward_text_inference_ratio_duration(
self,
tokens: List[List[int]],
prompt_tokens: List[List[int]],
prompt_features_lens: torch.Tensor,
speed: float,
):
"""
Process text for inference, given text tokens and prompts,
feature lengths are predicted with the ratio of token numbers.
"""
device = (
self.device if isinstance(self, DDP) else next(self.parameters()).device
)
cat_tokens = [
prompt_token + token for prompt_token, token in zip(prompt_tokens, tokens)
]
prompt_tokens_lens = torch.tensor(
[len(token) for token in prompt_tokens], dtype=torch.int64, device=device
)
cat_embed, cat_tokens_lens = self.forward_text_embed(cat_tokens)
features_lens = torch.ceil(
(prompt_features_lens / prompt_tokens_lens * cat_tokens_lens / speed)
).to(dtype=torch.int64)
text_condition, padding_mask = self.forward_text_condition(
cat_embed, cat_tokens_lens, features_lens
)
return text_condition, padding_mask
def forward(
self,
tokens: List[List[int]],
features: torch.Tensor,
features_lens: torch.Tensor,
noise: torch.Tensor,
t: torch.Tensor,
condition_drop_ratio: float = 0.0,
) -> torch.Tensor:
"""Forward pass of the model for training.
Args:
tokens: a list of list of token ids.
features: the acoustic features, with the shape (batch, seq_len, feat_dim).
features_lens: the length of each acoustic feature sequence, shape (batch,).
noise: the intitial noise, with the shape (batch, seq_len, feat_dim).
t: the time step, with the shape (batch, 1, 1).
condition_drop_ratio: the ratio of dropped text condition.
Returns:
fm_loss: the flow-matching loss.
"""
(text_condition, padding_mask,) = self.forward_text_train(
tokens=tokens,
features_lens=features_lens,
)
speech_condition_mask = condition_time_mask(
features_lens=features_lens,
mask_percent=(0.7, 1.0),
max_len=features.size(1),
)
speech_condition = torch.where(speech_condition_mask.unsqueeze(-1), 0, features)
if condition_drop_ratio > 0.0:
drop_mask = (
torch.rand(text_condition.size(0), 1, 1).to(text_condition.device)
> condition_drop_ratio
)
text_condition = text_condition * drop_mask
xt = features * t + noise * (1 - t)
ut = features - noise # (B, T, F)
vt = self.forward_fm_decoder(
t=t,
xt=xt,
text_condition=text_condition,
speech_condition=speech_condition,
padding_mask=padding_mask,
)
loss_mask = speech_condition_mask & (~padding_mask)
fm_loss = torch.mean((vt[loss_mask] - ut[loss_mask]) ** 2)
return fm_loss
def sample(
self,
tokens: List[List[int]],
prompt_tokens: List[List[int]],
prompt_features: torch.Tensor,
prompt_features_lens: torch.Tensor,
features_lens: Optional[torch.Tensor] = None,
speed: float = 1.0,
t_shift: float = 1.0,
duration: str = "predict",
num_step: int = 5,
guidance_scale: float = 0.5,
) -> torch.Tensor:
"""
Generate acoustic features, given text tokens, prompts feature
and prompt transcription's text tokens.
Args:
tokens: a list of list of text tokens.
prompt_tokens: a list of list of prompt tokens.
prompt_features: the prompt feature with the shape
(batch_size, seq_len, feat_dim).
prompt_features_lens: the length of each prompt feature,
with the shape (batch_size,).
features_lens: the length of the predicted eature, with the
shape (batch_size,). It is used only when duration is "real".
duration: "real" or "predict". If "real", the predicted
feature length is given by features_lens.
num_step: the number of steps to use in the ODE solver.
guidance_scale: the guidance scale for classifier-free guidance.
distill: whether to use the distillation model for sampling.
"""
assert duration in ["real", "predict"]
if duration == "predict":
(
text_condition,
padding_mask,
) = self.forward_text_inference_ratio_duration(
tokens=tokens,
prompt_tokens=prompt_tokens,
prompt_features_lens=prompt_features_lens,
speed=speed,
)
else:
assert features_lens is not None
text_condition, padding_mask = self.forward_text_inference_gt_duration(
tokens=tokens,
features_lens=features_lens,
prompt_tokens=prompt_tokens,
prompt_features_lens=prompt_features_lens,
)
batch_size, num_frames, _ = text_condition.shape
speech_condition = torch.nn.functional.pad(
prompt_features, (0, 0, 0, num_frames - prompt_features.size(1))
) # (B, T, F)
# False means speech condition positions.
speech_condition_mask = make_pad_mask(prompt_features_lens, num_frames)
speech_condition = torch.where(
speech_condition_mask.unsqueeze(-1),
torch.zeros_like(speech_condition),
speech_condition,
)
x0 = torch.randn(
batch_size, num_frames, self.feat_dim, device=text_condition.device
)
solver = EulerSolver(self, distill=self.distill, func_name="forward_fm_decoder")
x1 = solver.sample(
x=x0,
text_condition=text_condition,
speech_condition=speech_condition,
padding_mask=padding_mask,
num_step=num_step,
guidance_scale=guidance_scale,
t_shift=t_shift,
)
x1_wo_prompt_lens = (~padding_mask).sum(-1) - prompt_features_lens
x1_prompt = torch.zeros(
x1.size(0), prompt_features_lens.max(), x1.size(2), device=x1.device
)
x1_wo_prompt = torch.zeros(
x1.size(0), x1_wo_prompt_lens.max(), x1.size(2), device=x1.device
)
for i in range(x1.size(0)):
x1_wo_prompt[i, : x1_wo_prompt_lens[i], :] = x1[
i,
prompt_features_lens[i] : prompt_features_lens[i]
+ x1_wo_prompt_lens[i],
]
x1_prompt[i, : prompt_features_lens[i], :] = x1[
i, : prompt_features_lens[i]
]
return x1_wo_prompt, x1_wo_prompt_lens, x1_prompt, prompt_features_lens
def sample_intermediate(
self,
tokens: List[List[int]],
features: torch.Tensor,
features_lens: torch.Tensor,
noise: torch.Tensor,
speech_condition_mask: torch.Tensor,
t_start: torch.Tensor,
t_end: torch.Tensor,
num_step: int = 1,
guidance_scale: torch.Tensor = None,
) -> torch.Tensor:
"""
Generate acoustic features in intermediate timesteps.
Args:
tokens: List of list of token ids.
features: The acoustic features, with the shape (batch, seq_len, feat_dim).
features_lens: The length of each acoustic feature sequence,
with the shape (batch,).
noise: The initial noise, with the shape (batch, seq_len, feat_dim).
speech_condition_mask: The mask for speech condition, True means
non-condition positions, with the shape (batch, seq_len).
t_start: The start timestep, with the shape (batch, 1, 1).
t_end: The end timestep, with the shape (batch, 1, 1).
num_step: The number of steps for sampling.
guidance_scale: The scale for classifier-free guidance inference,
with the shape (batch, 1, 1).
distill: Whether to use distillation model.
"""
(text_condition, padding_mask,) = self.forward_text_train(
tokens=tokens,
features_lens=features_lens,
)
speech_condition = torch.where(speech_condition_mask.unsqueeze(-1), 0, features)
solver = EulerSolver(self, distill=self.distill, func_name="forward_fm_decoder")
x_t_end = solver.sample(
x=noise,
text_condition=text_condition,
speech_condition=speech_condition,
padding_mask=padding_mask,
num_step=num_step,
guidance_scale=guidance_scale,
t_start=t_start,
t_end=t_end,
)
x_t_end_lens = (~padding_mask).sum(-1)
return x_t_end, x_t_end_lens
class DistillTTSModelTrainWrapper(TtsModel):
"""Wrapper for training the distilled TTS model."""
def __init__(self, *args, **kwargs):
super().__init__(*args, **kwargs)
self.distill = True
def forward(
self,
tokens: List[List[int]],
features: torch.Tensor,
features_lens: torch.Tensor,
noise: torch.Tensor,
speech_condition_mask: torch.Tensor,
t_start: torch.Tensor,
t_end: torch.Tensor,
num_step: int = 1,
guidance_scale: torch.Tensor = None,
) -> torch.Tensor:
return self.sample_intermediate(
tokens=tokens,
features=features,
features_lens=features_lens,
noise=noise,
speech_condition_mask=speech_condition_mask,
t_start=t_start,
t_end=t_end,
num_step=num_step,
guidance_scale=guidance_scale,
)