nnet-combine.cc File Reference

#include "base/kaldi-common.h"
#include "util/common-utils.h"
#include "hmm/transition-model.h"
#include "nnet2/combine-nnet.h"
#include "nnet2/am-nnet.h"

Include dependency graph for nnet-combine.cc:

Go to the source code of this file.

Functions
int	main (int argc, char *argv[])

Function Documentation

main()

int main	(	int	argc,
		char *	argv[]
	)

Definition at line 27 of file nnet-combine.cc.

References kaldi::nnet2::CombineNnets(), SequentialTableReader< Holder >::Done(), ParseOptions::GetArg(), AmNnet::GetNnet(), KALDI_ASSERT, KALDI_LOG, rnnlm::n, SequentialTableReader< Holder >::Next(), ParseOptions::NumArgs(), ParseOptions::PrintUsage(), AmNnet::Read(), ParseOptions::Read(), TransitionModel::Read(), NnetCombineConfig::Register(), ParseOptions::Register(), Output::Stream(), Input::Stream(), SequentialTableReader< Holder >::Value(), AmNnet::Write(), and TransitionModel::Write().

                                 {
  try {
    using namespace kaldi;
    using namespace kaldi::nnet2;
    typedef kaldi::int32 int32;
    typedef kaldi::int64 int64;

    const char *usage =
        "Using a validation set, compute an optimal combination of a number of\n"
        "neural nets (the combination weights are separate for each layer and\n"
        "do not have to sum to one).  The optimization is BFGS, which is initialized\n"
        "from the best of the individual input neural nets (or as specified by\n"
        "--initial-model)\n"
        "\n"
        "Usage:  nnet-combine [options] <model-in1> <model-in2> ... <model-inN> <valid-examples-in> <model-out>\n"
        "\n"
        "e.g.:\n"
        " nnet-combine 1.1.nnet 1.2.nnet 1.3.nnet ark:valid.egs 2.nnet\n"
        "Caution: the first input neural net must not be a gradient.\n";
    
    bool binary_write = true;
    NnetCombineConfig combine_config;
    
    ParseOptions po(usage);
    po.Register("binary", &binary_write, "Write output in binary mode");
    
    combine_config.Register(&po);
    
    po.Read(argc, argv);
    
    if (po.NumArgs() < 3) {
      po.PrintUsage();
      exit(1);
    }
    
    std::string
        nnet1_rxfilename = po.GetArg(1),
        valid_examples_rspecifier = po.GetArg(po.NumArgs() - 1),
        nnet_wxfilename = po.GetArg(po.NumArgs());
    
    TransitionModel trans_model;
    AmNnet am_nnet1;
    {
      bool binary_read;
      Input ki(nnet1_rxfilename, &binary_read);
      trans_model.Read(ki.Stream(), binary_read);
      am_nnet1.Read(ki.Stream(), binary_read);
    }

    int32 num_nnets = po.NumArgs() - 2;
    std::vector<Nnet> nnets(num_nnets);
    nnets[0] = am_nnet1.GetNnet();
    am_nnet1.GetNnet() = Nnet(); // Clear it to save memory.

    for (int32 n = 1; n < num_nnets; n++) {
      TransitionModel trans_model;
      AmNnet am_nnet;
      bool binary_read;
      Input ki(po.GetArg(1 + n), &binary_read);
      trans_model.Read(ki.Stream(), binary_read);
      am_nnet.Read(ki.Stream(), binary_read);
      nnets[n] = am_nnet.GetNnet();
    }      
    
    std::vector<NnetExample> validation_set; // stores validation
    // frames.

    { // This block adds samples to "validation_set".
      SequentialNnetExampleReader example_reader(
          valid_examples_rspecifier);
      for (; !example_reader.Done(); example_reader.Next())
        validation_set.push_back(example_reader.Value());
      KALDI_LOG << "Read " << validation_set.size() << " examples from the "
                << "validation set.";
      KALDI_ASSERT(validation_set.size() > 0);
    }

    CombineNnets(combine_config,
                 validation_set,
                 nnets,
                 &(am_nnet1.GetNnet()));
    
    {
      Output ko(nnet_wxfilename, binary_write);
      trans_model.Write(ko.Stream(), binary_write);
      am_nnet1.Write(ko.Stream(), binary_write);
    }
    
    KALDI_LOG << "Finished combining neural nets, wrote model to "
              << nnet_wxfilename;
    return (validation_set.size() == 0 ? 1 : 0);
  } catch(const std::exception &e) {
    std::cerr << e.what() << '\n';
    return -1;
  }
}