text: // bin/est-mllt.cc
  // Copyright 2009-2011  Microsoft Corporation
  
  // See ../../COPYING for clarification regarding multiple authors
  //
  // 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 "gmm/am-diag-gmm.h"
  #include "tree/context-dep.h"
  #include "hmm/transition-model.h"
  #include "transform/mllt.h"
  
  int main(int argc, char *argv[]) {
    try {
      using namespace kaldi;
      typedef kaldi::int32 int32;
  
      const char *usage =
          "Do MLLT update\n"
          "Usage:  est-mllt [options] <mllt-mat-out> <stats-in1> <stats-in2> ... \n"
          "e.g.: est-mllt 2.mat 1a.macc 1b.macc ... \n"
          "Note: use compose-transforms <mllt-mat-out> <prev-mllt-mat> to combine with previous\n"
          "  MLLT or LDA transform, if any, and\n"
          "  gmm-transform-means to apply <mllt-mat-out> to GMM means.\n";
  
      bool binary = true;  // write in binary if true.
  
      ParseOptions po(usage);
      po.Register("binary", &binary, "Write output in binary mode");
  
      po.Read(argc, argv);
  
      if (po.NumArgs() < 2) {
        po.PrintUsage();
        exit(1);
      }
  
      std::string mllt_out_filename = po.GetArg(1);
  
      MlltAccs mllt_accs;
      for (int32 i = 2; i <= po.NumArgs(); i++) {
        std::string acc_filename = po.GetArg(i);
        bool binary_in, add = true;
        Input ki(acc_filename, &binary_in);
        mllt_accs.Read(ki.Stream(), binary_in, add);
      }
  
      Matrix<BaseFloat> mat(mllt_accs.Dim(), mllt_accs.Dim());
      mat.SetUnit();
      BaseFloat objf_impr, count;
      mllt_accs.Update(&mat, &objf_impr, &count);
  
      KALDI_LOG << "Overall objective function improvement for MLLT is "
                << (objf_impr/count) << " over " << count << " frames, logdet is "
                << mat.LogDet();
  
      Output ko(mllt_out_filename, binary);
      mat.Write(ko.Stream(), binary);
  
      return 0;
    } catch(const std::exception &e) {
      std::cerr << e.what() << '\n';
      return -1;
    }
  }
  
  
  