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authorAvneesh Saluja <asaluja@gmail.com>2013-03-28 18:28:16 -0700
committerAvneesh Saluja <asaluja@gmail.com>2013-03-28 18:28:16 -0700
commit3d8d656fa7911524e0e6885647173474524e0784 (patch)
tree81b1ee2fcb67980376d03f0aa48e42e53abff222 /decoder/incremental.cc
parentbe7f57fdd484e063775d7abf083b9fa4c403b610 (diff)
parent96fedabebafe7a38a6d5928be8fff767e411d705 (diff)
fixed conflicts
Diffstat (limited to 'decoder/incremental.cc')
-rw-r--r--decoder/incremental.cc167
1 files changed, 167 insertions, 0 deletions
diff --git a/decoder/incremental.cc b/decoder/incremental.cc
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+#include "incremental.h"
+
+#include "hg.h"
+#include "fdict.h"
+#include "tdict.h"
+
+#include "lm/enumerate_vocab.hh"
+#include "lm/model.hh"
+#include "search/applied.hh"
+#include "search/config.hh"
+#include "search/context.hh"
+#include "search/edge.hh"
+#include "search/edge_generator.hh"
+#include "search/rule.hh"
+#include "search/vertex.hh"
+#include "search/vertex_generator.hh"
+#include "util/exception.hh"
+
+#include <boost/scoped_ptr.hpp>
+#include <boost/scoped_array.hpp>
+
+#include <iostream>
+#include <vector>
+
+namespace {
+
+struct MapVocab : public lm::EnumerateVocab {
+ public:
+ MapVocab() {}
+
+ // Do not call after Lookup.
+ void Add(lm::WordIndex index, const StringPiece &str) {
+ const WordID cdec_id = TD::Convert(str.as_string());
+ if (cdec_id >= out_.size()) out_.resize(cdec_id + 1);
+ out_[cdec_id] = index;
+ }
+
+ // Assumes Add has been called and will never be called again.
+ lm::WordIndex FromCDec(WordID id) const {
+ return out_[out_.size() > id ? id : 0];
+ }
+
+ private:
+ std::vector<lm::WordIndex> out_;
+};
+
+template <class Model> class Incremental : public IncrementalBase {
+ public:
+ Incremental(const char *model_file, const std::vector<weight_t> &weights) :
+ IncrementalBase(weights),
+ m_(model_file, GetConfig()),
+ lm_(weights[FD::Convert("KLanguageModel")]),
+ oov_(weights[FD::Convert("KLanguageModel_OOV")]),
+ word_penalty_(weights[FD::Convert("WordPenalty")]) {
+ std::cerr << "Weights KLanguageModel " << lm_ << " KLanguageModel_OOV " << oov_ << " WordPenalty " << word_penalty_ << std::endl;
+ }
+
+ void Search(unsigned int pop_limit, const Hypergraph &hg) const;
+
+ private:
+ void ConvertEdge(const search::Context<Model> &context, search::Vertex *vertices, const Hypergraph::Edge &in, search::EdgeGenerator &gen) const;
+
+ lm::ngram::Config GetConfig() {
+ lm::ngram::Config ret;
+ ret.enumerate_vocab = &vocab_;
+ return ret;
+ }
+
+ MapVocab vocab_;
+
+ const Model m_;
+
+ const float lm_, oov_, word_penalty_;
+};
+
+void PrintApplied(const Hypergraph &hg, const search::Applied final) {
+ const std::vector<WordID> &words = static_cast<const Hypergraph::Edge*>(final.GetNote().vp)->rule_->e();
+ const search::Applied *child(final.Children());
+ for (std::vector<WordID>::const_iterator i = words.begin(); i != words.end(); ++i) {
+ if (*i > 0) {
+ std::cout << TD::Convert(*i) << ' ';
+ } else {
+ PrintApplied(hg, *child++);
+ }
+ }
+}
+
+template <class Model> void Incremental<Model>::Search(unsigned int pop_limit, const Hypergraph &hg) const {
+ boost::scoped_array<search::Vertex> out_vertices(new search::Vertex[hg.nodes_.size()]);
+ search::Config config(lm_, pop_limit, search::NBestConfig(1));
+ search::Context<Model> context(config, m_);
+ search::SingleBest best;
+
+ for (unsigned int i = 0; i < hg.nodes_.size() - 1; ++i) {
+ search::EdgeGenerator gen;
+ const Hypergraph::EdgesVector &down_edges = hg.nodes_[i].in_edges_;
+ for (unsigned int j = 0; j < down_edges.size(); ++j) {
+ unsigned int edge_index = down_edges[j];
+ ConvertEdge(context, out_vertices.get(), hg.edges_[edge_index], gen);
+ }
+ search::VertexGenerator<search::SingleBest> vertex_gen(context, out_vertices[i], best);
+ gen.Search(context, vertex_gen);
+ }
+ const search::Applied top = out_vertices[hg.nodes_.size() - 2].BestChild();
+ if (!top.Valid()) {
+ std::cout << "NO PATH FOUND" << std::endl;
+ } else {
+ PrintApplied(hg, top);
+ std::cout << "||| " << top.GetScore() << std::endl;
+ }
+}
+
+template <class Model> void Incremental<Model>::ConvertEdge(const search::Context<Model> &context, search::Vertex *vertices, const Hypergraph::Edge &in, search::EdgeGenerator &gen) const {
+ const std::vector<WordID> &e = in.rule_->e();
+ std::vector<lm::WordIndex> words;
+ words.reserve(e.size());
+ std::vector<search::PartialVertex> nts;
+ unsigned int terminals = 0;
+ float score = 0.0;
+ for (std::vector<WordID>::const_iterator word = e.begin(); word != e.end(); ++word) {
+ if (*word <= 0) {
+ nts.push_back(vertices[in.tail_nodes_[-*word]].RootPartial());
+ if (nts.back().Empty()) return;
+ score += nts.back().Bound();
+ words.push_back(lm::kMaxWordIndex);
+ } else {
+ ++terminals;
+ words.push_back(vocab_.FromCDec(*word));
+ }
+ }
+
+ search::PartialEdge out(gen.AllocateEdge(nts.size()));
+
+ memcpy(out.NT(), &nts[0], sizeof(search::PartialVertex) * nts.size());
+
+ search::Note note;
+ note.vp = &in;
+ out.SetNote(note);
+
+ score += in.rule_->GetFeatureValues().dot(cdec_weights_);
+ score -= static_cast<float>(terminals) * word_penalty_ / M_LN10;
+ search::ScoreRuleRet res(search::ScoreRule(context.LanguageModel(), words, out.Between()));
+ score += res.prob * lm_ + static_cast<float>(res.oov) * oov_;
+
+ out.SetScore(score);
+
+ gen.AddEdge(out);
+}
+
+} // namespace
+
+IncrementalBase *IncrementalBase::Load(const char *model_file, const std::vector<weight_t> &weights) {
+ lm::ngram::ModelType model_type;
+ if (!lm::ngram::RecognizeBinary(model_file, model_type)) model_type = lm::ngram::PROBING;
+ switch (model_type) {
+ case lm::ngram::PROBING:
+ return new Incremental<lm::ngram::ProbingModel>(model_file, weights);
+ case lm::ngram::REST_PROBING:
+ return new Incremental<lm::ngram::RestProbingModel>(model_file, weights);
+ default:
+ UTIL_THROW(util::Exception, "Sorry this lm type isn't supported yet.");
+ }
+}
+
+IncrementalBase::~IncrementalBase() {}
+
+IncrementalBase::IncrementalBase(const std::vector<weight_t> &weights) : cdec_weights_(weights) {}