DeepSpeech/native_client/ctcdecode/ctc_beam_search_decoder.h
Reuben Morais 440893c58d Simplify ctcdecode API signatures to avoid nested STL structures
Flatten structure to avoid nested STL structures which are awkward to
wrap with SWIG and slower at runtime.
2018-11-03 07:48:02 -03:00

71 lines
2.2 KiB
C++

#ifndef CTC_BEAM_SEARCH_DECODER_H_
#define CTC_BEAM_SEARCH_DECODER_H_
#include <string>
#include <vector>
#include "scorer.h"
#include "output.h"
#include "alphabet.h"
/* CTC Beam Search Decoder
* Parameters:
* probs_seq: 2-D vector that each element is a vector of probabilities
* over alphabet of one time step.
* alphabet: The alphabet.
* beam_size: The width of beam search.
* cutoff_prob: Cutoff probability for pruning.
* cutoff_top_n: Cutoff number for pruning.
* ext_scorer: External scorer to evaluate a prefix, which consists of
* n-gram language model scoring and word insertion term.
* Default null, decoding the input sample without scorer.
* Return:
* A vector that each element is a pair of score and decoding result,
* in desending order.
*/
std::vector<Output> ctc_beam_search_decoder(
const double* probs,
int time_dim,
int class_dim,
const Alphabet &alphabet,
size_t beam_size,
double cutoff_prob,
size_t cutoff_top_n,
Scorer *ext_scorer);
/* CTC Beam Search Decoder for batch data
* Parameters:
* probs_seq: 3-D vector that each element is a 2-D vector that can be used
* by ctc_beam_search_decoder().
* alphabet: The alphabet.
* beam_size: The width of beam search.
* num_processes: Number of threads for beam search.
* cutoff_prob: Cutoff probability for pruning.
* cutoff_top_n: Cutoff number for pruning.
* ext_scorer: External scorer to evaluate a prefix, which consists of
* n-gram language model scoring and word insertion term.
* Default null, decoding the input sample without scorer.
* Return:
* A 2-D vector that each element is a vector of beam search decoding
* result for one audio sample.
*/
std::vector<std::vector<Output>>
ctc_beam_search_decoder_batch(
const double* probs,
int batch_size,
int time_dim,
int class_dim,
const int* seq_lengths,
int seq_lengths_size,
const Alphabet &alphabet,
size_t beam_size,
size_t num_processes,
double cutoff_prob,
size_t cutoff_top_n,
Scorer *ext_scorer);
#endif // CTC_BEAM_SEARCH_DECODER_H_