Blame view

src/nnet2bin/nnet-subset-egs.cc 3.28 KB
8dcb6dfcb   Yannick Estève   first commit
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
  // nnet2bin/nnet-subset-egs.cc
  
  // Copyright 2012  Johns Hopkins University (author:  Daniel Povey)
  // Copyright 2014  Vimal Manohar
  
  // 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 "hmm/transition-model.h"
  #include "nnet2/nnet-example-functions.h"
  
  int main(int argc, char *argv[]) {
    try {
      using namespace kaldi;
      using namespace kaldi::nnet2;
      typedef kaldi::int32 int32;
      typedef kaldi::int64 int64;
  
      const char *usage =
          "Creates a random subset of the input examples, of a specified size.
  "
          "Uses no more memory than the size of the subset.
  "
          "
  "
          "Usage:  nnet-subset-egs [options] <egs-rspecifier> [<egs-wspecifier2> ...]
  "
          "
  "
          "e.g.
  "
          "nnet-subset-egs [args] ark:- | nnet-subset-egs --n=1000 ark:- ark:subset.egs
  ";
      
      int32 srand_seed = 0;
      int32 n = 1000;
      bool randomize_order = true;
      ParseOptions po(usage);
      po.Register("srand", &srand_seed, "Seed for random number generator ");
      po.Register("n", &n, "Number of examples to output");
      po.Register("randomize-order", &randomize_order, "If true, randomize the order "
                  "of the output");
      
      po.Read(argc, argv);
      
      srand(srand_seed);
      
      if (po.NumArgs() != 2) {
        po.PrintUsage();
        exit(1);
      }
  
      std::string examples_rspecifier = po.GetArg(1),
          examples_wspecifier = po.GetArg(2);
  
      std::vector<std::pair<std::string, NnetExample> > egs;
      egs.reserve(n);    
      
      SequentialNnetExampleReader example_reader(examples_rspecifier);
  
      int64 num_read = 0;
      for (; !example_reader.Done(); example_reader.Next()) {
        num_read++;
        if (num_read <= n) {
          egs.resize(egs.size() + 1);
          egs.back().first = example_reader.Key();
          egs.back().second = example_reader.Value();
        } else {
          BaseFloat keep_prob = n / static_cast<BaseFloat>(num_read);
          if (WithProb(keep_prob)) { // With probability "keep_prob"
            int32 index = RandInt(0, n-1);
            egs[index].first = example_reader.Key();
            egs[index].second = example_reader.Value();
          }
        }
      }
      if (randomize_order)
        std::random_shuffle(egs.begin(), egs.end());
  
      NnetExampleWriter writer(examples_wspecifier);
      for (size_t i = 0; i < egs.size(); i++) {
        writer.Write(egs[i].first, egs[i].second);
      }
      
      KALDI_LOG << "Selected a subset of " << egs.size() << " out of " << num_read
                << " neural-network training examples ";
      
      return (num_read != 0 ? 0 : 1);
    } catch(const std::exception &e) {
      std::cerr << e.what() << '
  ';
      return -1;
    }
  }