main routine to collect frame level MPE style posteriors

git-svn-id: https://svn.code.sf.net/p/kaldi/code/trunk@894 5e6a8d80-dfce-4ca6-a32a-6e07a63d50c8

src/latbin/lattice-to-mpe-post.cc

+// latbin/lattice-to-mpe-post.cc
+
+// Copyright 2009-2012  Chao Weng 
+
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//  http://www.apache.org/licenses/LICENSE-2.0
+//
+// THIS CODE IS PROVIDED *AS IS* BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+// KIND, EITHER EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION ANY IMPLIED
+// WARRANTIES OR CONDITIONS OF TITLE, FITNESS FOR A PARTICULAR PURPOSE,
+// MERCHANTABLITY OR NON-INFRINGEMENT.
+// See the Apache 2 License for the specific language governing permissions and
+// limitations under the License.
+
+#include "base/kaldi-common.h"
+#include "util/common-utils.h"
+#include "fstext/fstext-lib.h"
+#include "lat/kaldi-lattice.h"
+#include "lat/lattice-functions.h"
+#include "gmm/am-diag-gmm.h"
+#include "hmm/transition-model.h"
+
+int main(int argc, char *argv[]) {
+  try {
+    typedef kaldi::int32 int32;
+    using fst::SymbolTable;
+    using fst::VectorFst;
+    using fst::StdArc;
+    using namespace kaldi;
+  
+    const char *usage =
+        "Do forward-backward and collect frame level MPE posteriors over\n" 
+        "lattices, which can be fed into gmm-acc-stats2 to do MPE traning,\n"
+        "Note: output posteriors do NOT fulfill the condition as regular one,\n"
+        "i.e., positive, and summed up to 1 within one frame.\n"
+        "Usage: lattice-to-mpe-post [options] <model> <num-posteriors-rspecifier>\n"
+        " <lats-rspecifier> <posteriors-wspecifier> \n"
+        "e.g.: lattice-to-mpe-post --acoustic-scale=0.1 1.mdl ark:num.post\n"
+        " ark:1.lats ark:1.post\n";
+
+    kaldi::BaseFloat acoustic_scale = 1.0, lm_scale = 1.0;
+    kaldi::ParseOptions po(usage);
+    po.Register("acoustic-scale", &acoustic_scale,
+                "Scaling factor for acoustic likelihoods");
+    po.Register("lm-scale", &lm_scale,
+                "Scaling factor for \"graph costs\" (including LM costs)");
+    po.Read(argc, argv);
+
+    if (po.NumArgs() != 4) {
+      po.PrintUsage();
+      exit(1);
+    }
+
+    if (acoustic_scale == 0.0)
+      KALDI_ERR << "Do not use a zero acoustic scale (cannot be inverted)";
+
+    std::string model_filename = po.GetArg(1), 
+        posteriors_rspecifier = po.GetArg(2),  
+        lats_rspecifier = po.GetArg(3),
+        posteriors_wspecifier = po.GetArg(4);
+
+    // Read as regular lattice
+    kaldi::SequentialLatticeReader lattice_reader(lats_rspecifier);
+    kaldi::RandomAccessPosteriorReader posteriors_reader(posteriors_rspecifier);
+    kaldi::PosteriorWriter posterior_writer(posteriors_wspecifier);
+
+    TransitionModel trans_model;
+    {
+      bool binary;
+      Input ki(model_filename, &binary);
+      trans_model.Read(ki.Stream(), binary);
+    }
+
+    int32 num_done = 0, num_err = 0;
+    double total_lat_frame_acc = 0.0, lat_frame_acc;
+    double total_time = 0, lat_time;
+
+    for (; !lattice_reader.Done(); lattice_reader.Next()) {
+      std::string key = lattice_reader.Key();
+      kaldi::Lattice lat = lattice_reader.Value();
+      lattice_reader.FreeCurrent();
+      if (acoustic_scale != 1.0 || lm_scale != 1.0)
+        fst::ScaleLattice(fst::LatticeScale(lm_scale, acoustic_scale), &lat);
+      
+      kaldi::uint64 props = lat.Properties(fst::kFstProperties, false);
+      if (!(props & fst::kTopSorted)) {
+        if (fst::TopSort(&lat) == false)
+          KALDI_ERR << "Cycles detected in lattice.";
+      }
+      
+      vector< std::map<int32, char> > arc_accs;
+      if (!posteriors_reader.HasKey(key)) {
+        num_err++;
+      } else {
+        const Posterior &posterior = posteriors_reader.Value(key);
+        for (size_t i = 0; i < posterior.size(); i++) {
+          for (size_t j = 0; j < posterior[i].size(); j++) {
+            int32 tid = posterior[i][j].first,  // transition identifier.
+                tstate = trans_model.TransitionIdToTransitionState(tid),
+                phone = trans_model.TransitionStateToPhone(tstate);
+            arc_accs[i][phone] = 1;
+          }
+        }
+      }
+       
+      kaldi::Posterior post;
+      lat_frame_acc = kaldi::LatticeForwardBackwardMpe(lat, trans_model,
+                                                       arc_accs, &post);
+      total_lat_frame_acc += lat_frame_acc;
+      lat_time = post.size();
+      total_time += lat_time;
+
+      KALDI_VLOG(2) << "Processed lattice for utterance: " << key << "; found "
+                    << lat.NumStates() << " states and " << fst::NumArcs(lat)
+                    << " arcs. Average frame accuracies = " << (lat_frame_acc/lat_time)
+                    << " over " << lat_time << " frames.";
+      
+      posterior_writer.Write(key, post);
+      num_done++;
+    }
+
+    KALDI_LOG << "Overall average log-like/frame is "
+              << (total_lat_frame_acc/total_time) << " over " << total_time
+              << " frames.";
+    KALDI_LOG << "Done " << num_done << " lattices.";
+    return (num_done != 0 ? 0 : 1);
+  } catch(const std::exception& e) {
+    std::cerr << e.what();
+    return -1;
+  }
+}