FunASR/funasr/punctuation/target_delay_transformer.py

131 lines
4.4 KiB
Python

from typing import Any
from typing import List
from typing import Tuple
import torch
import torch.nn as nn
from funasr.modules.embedding import PositionalEncoding
from funasr.modules.embedding import SinusoidalPositionEncoder
#from funasr.models.encoder.transformer_encoder import TransformerEncoder as Encoder
from funasr.punctuation.sanm_encoder import SANMEncoder as Encoder
#from funasr.modules.mask import subsequent_n_mask
from funasr.punctuation.abs_model import AbsPunctuation
class TargetDelayTransformer(AbsPunctuation):
def __init__(
self,
vocab_size: int,
punc_size: int,
pos_enc: str = None,
embed_unit: int = 128,
att_unit: int = 256,
head: int = 2,
unit: int = 1024,
layer: int = 4,
dropout_rate: float = 0.5,
):
super().__init__()
if pos_enc == "sinusoidal":
# pos_enc_class = PositionalEncoding
pos_enc_class = SinusoidalPositionEncoder
elif pos_enc is None:
def pos_enc_class(*args, **kwargs):
return nn.Sequential() # indentity
else:
raise ValueError(f"unknown pos-enc option: {pos_enc}")
self.embed = nn.Embedding(vocab_size, embed_unit)
self.encoder = Encoder(
input_size=embed_unit,
output_size=att_unit,
attention_heads=head,
linear_units=unit,
num_blocks=layer,
dropout_rate=dropout_rate,
input_layer="pe",
# pos_enc_class=pos_enc_class,
padding_idx=0,
)
self.decoder = nn.Linear(att_unit, punc_size)
# def _target_mask(self, ys_in_pad):
# ys_mask = ys_in_pad != 0
# m = subsequent_n_mask(ys_mask.size(-1), 5, device=ys_mask.device).unsqueeze(0)
# return ys_mask.unsqueeze(-2) & m
def forward(self, input: torch.Tensor, text_lengths: torch.Tensor) -> Tuple[torch.Tensor, None]:
"""Compute loss value from buffer sequences.
Args:
input (torch.Tensor): Input ids. (batch, len)
hidden (torch.Tensor): Target ids. (batch, len)
"""
x = self.embed(input)
# mask = self._target_mask(input)
h, _, _ = self.encoder(x, text_lengths)
y = self.decoder(h)
return y, None
def with_vad(self):
return False
def score(self, y: torch.Tensor, state: Any, x: torch.Tensor) -> Tuple[torch.Tensor, Any]:
"""Score new token.
Args:
y (torch.Tensor): 1D torch.int64 prefix tokens.
state: Scorer state for prefix tokens
x (torch.Tensor): encoder feature that generates ys.
Returns:
tuple[torch.Tensor, Any]: Tuple of
torch.float32 scores for next token (vocab_size)
and next state for ys
"""
y = y.unsqueeze(0)
h, _, cache = self.encoder.forward_one_step(self.embed(y), self._target_mask(y), cache=state)
h = self.decoder(h[:, -1])
logp = h.log_softmax(dim=-1).squeeze(0)
return logp, cache
def batch_score(self, ys: torch.Tensor, states: List[Any], xs: torch.Tensor) -> Tuple[torch.Tensor, List[Any]]:
"""Score new token batch.
Args:
ys (torch.Tensor): torch.int64 prefix tokens (n_batch, ylen).
states (List[Any]): Scorer states for prefix tokens.
xs (torch.Tensor):
The encoder feature that generates ys (n_batch, xlen, n_feat).
Returns:
tuple[torch.Tensor, List[Any]]: Tuple of
batchfied scores for next token with shape of `(n_batch, vocab_size)`
and next state list for ys.
"""
# merge states
n_batch = len(ys)
n_layers = len(self.encoder.encoders)
if states[0] is None:
batch_state = None
else:
# transpose state of [batch, layer] into [layer, batch]
batch_state = [torch.stack([states[b][i] for b in range(n_batch)]) for i in range(n_layers)]
# batch decoding
h, _, states = self.encoder.forward_one_step(self.embed(ys), self._target_mask(ys), cache=batch_state)
h = self.decoder(h[:, -1])
logp = h.log_softmax(dim=-1)
# transpose state of [layer, batch] into [batch, layer]
state_list = [[states[i][b] for i in range(n_layers)] for b in range(n_batch)]
return logp, state_list