Add sentence WER for NLP input (#35)

Author: nishchalb

src/fstalign.cpp

@@ -678,9 +678,10 @@ void HandleWer(FstLoader *refLoader, FstLoader *hypLoader, SynonymEngine *engine
       RecordSpeakerSwitchWer(stitches, alignerOptions.speaker_switch_context_size);
     }
 
-    // Calculate and record per-speaker WER
+    // Calculate and record supplementary WER
     RecordSpeakerWer(stitches);
     RecordTagWer(stitches);
+    RecordSentenceWer(stitches);
 
     if (!output_nlp.empty()) {
       ofstream nlp_ostream(output_nlp);

src/wer.cpp

@@ -74,6 +74,34 @@ void RecordWer(spWERA topAlignment) {
   }
 }
 
+void RecordSentenceWer(vector<shared_ptr<Stitching>> stitches) {
+  std::set<std::string> eos_punc{".", "?", "!"};
+  vector<WerResult> sentence_wers;
+  WerResult curr_wer = {0, 0, 0, 0, 0};
+  for (auto &stitch : stitches) {
+      curr_wer.deletions += stitch->comment.rfind("del", 0) == 0;
+      curr_wer.insertions += stitch->comment.rfind("ins", 0) == 0;
+      curr_wer.substitutions += stitch->comment.rfind("sub", 0) == 0;
+      curr_wer.numWordsInReference += stitch->comment.rfind("ins", 0) != 0;
+
+      // Check if we hit EOS
+      if (eos_punc.find(stitch->nlpRow.punctuation) != eos_punc.end()) {
+        sentence_wers.push_back(curr_wer);
+        curr_wer = {0, 0, 0, 0, 0};
+      }
+  }
+  // Add last one if its empty case
+  if (curr_wer.numWordsInReference > 0) {
+    sentence_wers.push_back(curr_wer);
+  }
+
+  // Add to log
+  for (int i=0; i < sentence_wers.size(); i++) {
+    RecordWerResult(jsonLogger::JsonLogger::getLogger().root["wer"]["sentenceWer"][i], sentence_wers[i]);
+  }
+}
+
+
 void RecordSpeakerWer(vector<shared_ptr<Stitching>> stitches) {
   // Note: stitches must have already been aligned to NLP rows
   // Logic for segment boundaries copied from speaker switch WER code

src/wer.h

@@ -39,6 +39,7 @@ void RecordWerResult(Json::Value &json, WerResult wr);
 void RecordWer(spWERA topAlignment);
 void RecordSpeakerWer(vector<shared_ptr<Stitching>> stitches);
 void RecordSpeakerSwitchWer(vector<shared_ptr<Stitching>> stitches, int speaker_switch_context_size);
+void RecordSentenceWer(vector<shared_ptr<Stitching>> stitches);
 void RecordTagWer(vector<shared_ptr<Stitching>> stitches);
 void RecordCaseWer(vector<shared_ptr<Stitching>> aligned_stitches);