espnet2.asr_transducer.decoder.abs_decoder.AbsDecoder

source

class espnet2.asr_transducer.decoder.abs_decoder.AbsDecoder(*args, **kwargs)

Bases: Module, ABC

Abstract decoder module.

Initialize internal Module state, shared by both nn.Module and ScriptModule.

abstractmethod batch_score(hyps: List[Any]) → Tuple[Tensor, List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None]]

One-step forward hypotheses.

• Parameters:hyps – Hypotheses.
• Returns: Decoder output sequences. states: Decoder hidden states.
• Return type: out

abstractmethod create_batch_states(new_states: List[List[Dict[str, Tensor | None]] | List[List[Tensor]] | Tuple[Tensor, Tensor | None]]) → List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None]

Create batch of decoder hidden states given a list of new states.

• Parameters:new_states – Decoder hidden states.
• Returns: Decoder hidden states.

abstractmethod forward(labels: Tensor) → Tensor

Encode source label sequences.

• Parameters:labels – Label ID sequences.
• Returns: Decoder output sequences.

abstractmethod init_state(batch_size: int) → List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, tensor | None]

Initialize decoder states.

• Parameters:batch_size – Batch size.
• Returns: Decoder hidden states.

abstractmethod score(label_sequence: List[int], states: List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None]) → Tuple[Tensor, List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None]]

One-step forward hypothesis.

• Parameters:
  • label_sequence – Current label sequence.
  • state – Decoder hidden states.
• Returns: Decoder output sequence. state: Decoder hidden states.
• Return type: out

abstractmethod select_state(states: List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None], idx: int = 0) → List[Dict[str, Tensor]] | List[Tensor] | Tuple[Tensor, Tensor | None]

Get specified ID state from batch of states, if provided.

• Parameters:
  • states – Decoder hidden states.
  • idx – State ID to extract.
• Returns: Decoder hidden state for given ID.

abstractmethod set_device(device: Tensor) → None

Set GPU device to use.

• Parameters:device – Device ID.