[scripts] improve some comments

egs/wsj/s5/utils/data/combine_short_segments.sh

@@ -16,17 +16,22 @@
 
 # begin configuration section
 cleanup=true
-speaker_only=false
+speaker_only=false  # If true, utterances are only combined from the same speaker.
+                    # It may be useful for the speaker recognition task.
+                    # If false, utterances are preferentially combined from the same speaker,
+                    # and then combined across different speakers.
 # end configuration section
 
+
 . utils/parse_options.sh
 
 if [ $# != 3 ]; then
   echo "Usage: "
   echo "  $0 [options] <srcdir> <min-segment-length-in-seconds> <dir>"
   echo "e.g.:"
   echo " $0 data/train 1.55 data/train_comb"
-  # options documentation here.
+  echo " Options:"
+  echo "  --speaker-only <true|false>  # options to internal/choose_utts_to_combine.py, default false."
   exit 1;
 fi
 

egs/wsj/s5/utils/data/internal/choose_utts_to_combine.py

@@ -39,9 +39,9 @@
                     help="Minimum utterance duration")
 parser.add_argument("--merge-within-speakers-only", type = str, default = 'false',
                     choices = ['true', 'false'],
-                    help="If true, utterances were only combined from the same speaker."
+                    help="If true, utterances are only combined from the same speaker."
                     "It may be useful for the speaker recognition task."
-                    "If false, utterances were preferentially combined from the same speaker,"
+                    "If false, utterances are preferentially combined from the same speaker,"
                     "and then combined across different speakers.")
 parser.add_argument("spk2utt_in", type = str, metavar = "<spk2utt-in>",
                     help="Filename of [input] speaker to utterance map needed "
@@ -222,8 +222,8 @@ def SelfTest():
 # This function figures out the grouping of utterances.
 # The input is:
 # 'min_duration' which is the minimum utterance length in seconds.
-# 'merge_within_speakers_only' which is the option to control if 
-# utterances were only combined from the same speaker.
+# 'merge_within_speakers_only' which is a ['true', 'false'] choice.
+# If true, then utterances are only combined if they belong to the same speaker.
 # 'spk2utt' which is a list of pairs (speaker-id, [list-of-utterances])
 # 'utt2dur' which is a dict from utterance-id to duration (as a float)
 # It returns a lists of lists of utterances; each list corresponds to