mosesdecoder/lm/wrappers/nplm.hh
2015-04-30 12:05:11 +07:00

86 lines
1.9 KiB
C++

#ifndef LM_WRAPPERS_NPLM_H
#define LM_WRAPPERS_NPLM_H
#include "lm/facade.hh"
#include "lm/max_order.hh"
#include "util/string_piece.hh"
#include <boost/thread/tss.hpp>
#include <boost/scoped_ptr.hpp>
/* Wrapper to NPLM "by Ashish Vaswani, with contributions from David Chiang
* and Victoria Fossum."
* http://nlg.isi.edu/software/nplm/
*/
namespace nplm {
class vocabulary;
class neuralLM;
} // namespace nplm
namespace lm {
namespace np {
class Vocabulary : public base::Vocabulary {
public:
Vocabulary(const nplm::vocabulary &vocab);
~Vocabulary();
WordIndex Index(const std::string &str) const;
// TODO: lobby them to support StringPiece
WordIndex Index(const StringPiece &str) const {
return Index(std::string(str.data(), str.size()));
}
lm::WordIndex NullWord() const { return null_word_; }
private:
const nplm::vocabulary &vocab_;
const lm::WordIndex null_word_;
};
// Sorry for imposing my limitations on your code.
#define NPLM_MAX_ORDER 7
struct State {
WordIndex words[NPLM_MAX_ORDER - 1];
};
class Backend;
class Model : public lm::base::ModelFacade<Model, State, Vocabulary> {
private:
typedef lm::base::ModelFacade<Model, State, Vocabulary> P;
public:
// Does this look like an NPLM?
static bool Recognize(const std::string &file);
explicit Model(const std::string &file, std::size_t cache_size = 1 << 20);
~Model();
FullScoreReturn FullScore(const State &from, const WordIndex new_word, State &out_state) const;
FullScoreReturn FullScoreForgotState(const WordIndex *context_rbegin, const WordIndex *context_rend, const WordIndex new_word, State &out_state) const;
private:
boost::scoped_ptr<nplm::neuralLM> base_instance_;
mutable boost::thread_specific_ptr<Backend> backend_;
Vocabulary vocab_;
lm::WordIndex null_word_;
const std::size_t cache_size_;
};
} // namespace np
} // namespace lm
#endif // LM_WRAPPERS_NPLM_H