"""ASR Interface module."""
import argparse
from espnet.bin.asr_train import get_parser
from espnet.utils.dynamic_import import dynamic_import
from espnet.utils.fill_missing_args import fill_missing_args
[docs]class ASRInterface:
"""ASR Interface for ESPnet model implementation."""
[docs] @staticmethod
def add_arguments(parser):
"""Add arguments to parser."""
return parser
[docs] @classmethod
def build(cls, idim: int, odim: int, **kwargs):
"""Initialize this class with python-level args.
Args:
idim (int): The number of an input feature dim.
odim (int): The number of output vocab.
Returns:
ASRinterface: A new instance of ASRInterface.
"""
def wrap(parser):
return get_parser(parser, required=False)
args = argparse.Namespace(**kwargs)
args = fill_missing_args(args, wrap)
args = fill_missing_args(args, cls.add_arguments)
return cls(idim, odim, args)
[docs] def forward(self, xs, ilens, ys):
"""Compute loss for training.
:param xs:
For pytorch, batch of padded source sequences torch.Tensor (B, Tmax, idim)
For chainer, list of source sequences chainer.Variable
:param ilens: batch of lengths of source sequences (B)
For pytorch, torch.Tensor
For chainer, list of int
:param ys:
For pytorch, batch of padded source sequences torch.Tensor (B, Lmax)
For chainer, list of source sequences chainer.Variable
:return: loss value
:rtype: torch.Tensor for pytorch, chainer.Variable for chainer
"""
raise NotImplementedError("forward method is not implemented")
[docs] def recognize(self, x, recog_args, char_list=None, rnnlm=None):
"""Recognize x for evaluation.
:param ndarray x: input acouctic feature (B, T, D) or (T, D)
:param namespace recog_args: argment namespace contraining options
:param list char_list: list of characters
:param torch.nn.Module rnnlm: language model module
:return: N-best decoding results
:rtype: list
"""
raise NotImplementedError("recognize method is not implemented")
[docs] def recognize_batch(self, x, recog_args, char_list=None, rnnlm=None):
"""Beam search implementation for batch.
:param torch.Tensor x: encoder hidden state sequences (B, Tmax, Henc)
:param namespace recog_args: argument namespace containing options
:param list char_list: list of characters
:param torch.nn.Module rnnlm: language model module
:return: N-best decoding results
:rtype: list
"""
raise NotImplementedError("Batch decoding is not supported yet.")
[docs] def calculate_all_attentions(self, xs, ilens, ys):
"""Calculate attention.
:param list xs: list of padded input sequences [(T1, idim), (T2, idim), ...]
:param ndarray ilens: batch of lengths of input sequences (B)
:param list ys: list of character id sequence tensor [(L1), (L2), (L3), ...]
:return: attention weights (B, Lmax, Tmax)
:rtype: float ndarray
"""
raise NotImplementedError("calculate_all_attentions method is not implemented")
[docs] def calculate_all_ctc_probs(self, xs, ilens, ys):
"""Calculate CTC probability.
:param list xs_pad: list of padded input sequences [(T1, idim), (T2, idim), ...]
:param ndarray ilens: batch of lengths of input sequences (B)
:param list ys: list of character id sequence tensor [(L1), (L2), (L3), ...]
:return: CTC probabilities (B, Tmax, vocab)
:rtype: float ndarray
"""
raise NotImplementedError("calculate_all_ctc_probs method is not implemented")
@property
def attention_plot_class(self):
"""Get attention plot class."""
from espnet.asr.asr_utils import PlotAttentionReport
return PlotAttentionReport
@property
def ctc_plot_class(self):
"""Get CTC plot class."""
from espnet.asr.asr_utils import PlotCTCReport
return PlotCTCReport
[docs] def get_total_subsampling_factor(self):
"""Get total subsampling factor."""
raise NotImplementedError(
"get_total_subsampling_factor method is not implemented"
)
[docs] def encode(self, feat):
"""Encode feature in `beam_search` (optional).
Args:
x (numpy.ndarray): input feature (T, D)
Returns:
torch.Tensor for pytorch, chainer.Variable for chainer:
encoded feature (T, D)
"""
raise NotImplementedError("encode method is not implemented")
[docs] def scorers(self):
"""Get scorers for `beam_search` (optional).
Returns:
dict[str, ScorerInterface]: dict of `ScorerInterface` objects
"""
raise NotImplementedError("decoders method is not implemented")
predefined_asr = {
"pytorch": {
"rnn": "espnet.nets.pytorch_backend.e2e_asr:E2E",
"transducer": "espnet.nets.pytorch_backend.e2e_asr_transducer:E2E",
"transformer": "espnet.nets.pytorch_backend.e2e_asr_transformer:E2E",
"conformer": "espnet.nets.pytorch_backend.e2e_asr_conformer:E2E",
},
"chainer": {
"rnn": "espnet.nets.chainer_backend.e2e_asr:E2E",
"transformer": "espnet.nets.chainer_backend.e2e_asr_transformer:E2E",
},
}
[docs]def dynamic_import_asr(module, backend):
"""Import ASR models dynamically.
Args:
module (str): module_name:class_name or alias in `predefined_asr`
backend (str): NN backend. e.g., pytorch, chainer
Returns:
type: ASR class
"""
model_class = dynamic_import(module, predefined_asr.get(backend, dict()))
assert issubclass(
model_class, ASRInterface
), f"{module} does not implement ASRInterface"
return model_class