1 // fstprune.cc
2
3 // Licensed under the Apache License, Version 2.0 (the "License");
4 // you may not use this file except in compliance with the License.
5 // You may obtain a copy of the License at
6 //
7 // http://www.apache.org/licenses/LICENSE-2.0
8 //
9 // Unless required by applicable law or agreed to in writing, software
10 // distributed under the License is distributed on an "AS IS" BASIS,
11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 // See the License for the specific language governing permissions and
13 // limitations under the License.
14 //
15 // Copyright 2005-2010 Google, Inc.
16 // Author: allauzen@google.com (Cyril Allauzen)
17 // Modified: jpr@google.com (Jake Ratkiewicz) to use FstClass
18 //
19 // \file
20 // Prunes states and arcs of an FST w.r.t. the shortest path weight.
21 //
22
23 #include <fst/script/prune.h>
24
25 DEFINE_double(delta, fst::kDelta, "Comparison/quantization delta");
26 DEFINE_int64(nstate, fst::kNoStateId, "State number threshold");
27 DEFINE_string(weight, "", "Weight threshold");
28
29
main(int argc,char ** argv)30 int main(int argc, char **argv) {
31 namespace s = fst::script;
32 using fst::script::FstClass;
33 using fst::script::MutableFstClass;
34 using fst::script::WeightClass;
35
36 string usage = "Prunes states and arcs of an FST.\n\n Usage: ";
37 usage += argv[0];
38 usage += " [in.fst [out.fst]]\n";
39
40 std::set_new_handler(FailedNewHandler);
41 SET_FLAGS(usage.c_str(), &argc, &argv, true);
42 if (argc > 3) {
43 ShowUsage();
44 return 1;
45 }
46
47 string in_name = (argc > 1 && strcmp(argv[1], "-") != 0) ? argv[1] : "";
48 string out_name = argc > 2 ? argv[2] : "";
49
50 MutableFstClass *fst = MutableFstClass::Read(in_name, true);
51 if (!fst) return 1;
52
53 WeightClass weight_threshold = FLAGS_weight.empty() ?
54 WeightClass::Zero() :
55 WeightClass(fst->WeightType(), FLAGS_weight);
56
57 s::PruneOptions opts(weight_threshold, FLAGS_nstate, 0, FLAGS_delta);
58
59 s::Prune(fst, opts);
60
61 fst->Write(out_name);
62
63 return 0;
64 }
65