1 // fstrmepsilon.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: riley@google.com (Michael Riley)
17 // Modified: jpr@google.com (Jake Ratkiewicz) to use FstClass
18 //
19 // \file
20 // Removes epsilons from an FST.
21 //
22
23 #include <fst/script/rmepsilon.h>
24
25 DEFINE_bool(connect, true, "Trim output");
26 DEFINE_double(delta, fst::kDelta, "Comparison/quantization delta");
27 DEFINE_int64(nstate, fst::kNoStateId, "State number threshold");
28 DEFINE_bool(reverse, false, "Perform in the reverse direction");
29 DEFINE_string(weight, "", "Weight threshold");
30 DEFINE_string(queue_type, "auto", "Queue type: one of: \"auto\", "
31 "\"fifo\", \"lifo\", \"shortest\", \"state\", \"top\"");
32
main(int argc,char ** argv)33 int main(int argc, char **argv) {
34 namespace s = fst::script;
35 using fst::script::FstClass;
36 using fst::script::MutableFstClass;
37 using fst::script::VectorFstClass;
38 using fst::script::WeightClass;
39
40 string usage = "Removes epsilons from an FST.\n\n Usage: ";
41 usage += argv[0];
42 usage += " [in.fst [out.fst]]\n";
43
44 std::set_new_handler(FailedNewHandler);
45 SET_FLAGS(usage.c_str(), &argc, &argv, true);
46 if (argc > 3) {
47 ShowUsage();
48 return 1;
49 }
50
51 string in_fname = (argc > 1 && strcmp(argv[1], "-") != 0) ? argv[1] : "";
52 string out_fname = argc > 2 ? argv[2] : "";
53
54 FstClass *ifst = FstClass::Read(in_fname);
55 if (!ifst) return 1;
56
57 WeightClass weight_threshold = FLAGS_weight.empty() ?
58 WeightClass::Zero() :
59 WeightClass(ifst->WeightType(), FLAGS_weight);
60
61 fst::QueueType qt;
62
63 if (FLAGS_queue_type == "auto") {
64 qt = fst::AUTO_QUEUE;
65 } else if (FLAGS_queue_type == "fifo") {
66 qt = fst::FIFO_QUEUE;
67 } else if (FLAGS_queue_type == "lifo") {
68 qt = fst::LIFO_QUEUE;
69 } else if (FLAGS_queue_type == "shortest") {
70 qt = fst::SHORTEST_FIRST_QUEUE;
71 } else if (FLAGS_queue_type == "state") {
72 qt = fst::STATE_ORDER_QUEUE;
73 } else if (FLAGS_queue_type == "top") {
74 qt = fst::TOP_ORDER_QUEUE;
75 } else {
76 LOG(ERROR) << "Unknown or unsupported queue type: " << FLAGS_queue_type;
77 return 1;
78 }
79
80 s::RmEpsilonOptions opts(qt, FLAGS_delta, FLAGS_connect,
81 weight_threshold, FLAGS_nstate);
82
83 MutableFstClass *ofst = new VectorFstClass(ifst->ArcType());
84 s::RmEpsilon(*ifst, ofst, FLAGS_reverse, opts);
85
86 ofst->Write(out_fname);
87
88 return 0;
89 }
90