Filter the training data of T < S for Wenet train recipe (#753)

* filter the case of T <  S  for training data

* fix style issues

* fix style issues

* fix style issues

Co-authored-by: 张云斌 <zhangyunbin@MacBook-Air.local>

egs/wenetspeech/ASR/pruned_transducer_stateless2/train.py

@@ -861,15 +861,41 @@ def run(rank, world_size, args):
     valid_cuts = wenetspeech.valid_cuts()
 
     def remove_short_and_long_utt(c: Cut):
-        # Keep only utterances with duration between 1 second and 15.0 seconds
+        # Keep only utterances with duration between 1 second and 10 seconds
         #
-        # Caution: There is a reason to select 15.0 here. Please see
+        # Caution: There is a reason to select 10.0 here. Please see
         # ../local/display_manifest_statistics.py
         #
         # You should use ../local/display_manifest_statistics.py to get
         # an utterance duration distribution for your dataset to select
         # the threshold
-        return 1.0 <= c.duration <= 15.0
+        if c.duration < 1.0 or c.duration > 10.0:
+            logging.warning(
+                f"Exclude cut with ID {c.id} from training. Duration: {c.duration}"
+            )
+            return False
+
+        # In pruned RNN-T, we require that T >= S
+        # where T is the number of feature frames after subsampling
+        # and S is the number of tokens in the utterance
+
+        # In ./conformer.py, the conv module uses the following expression
+        # for subsampling
+        T = ((c.num_frames - 1) // 2 - 1) // 2
+        tokens = c.supervisions[0].text.replace(" ", "")
+
+        if T < len(tokens):
+            logging.warning(
+                f"Exclude cut with ID {c.id} from training. "
+                f"Number of frames (before subsampling): {c.num_frames}. "
+                f"Number of frames (after subsampling): {T}. "
+                f"Text: {c.supervisions[0].text}. "
+                f"Tokens: {tokens}. "
+                f"Number of tokens: {len(tokens)}"
+            )
+            return False
+
+        return True
 
     train_cuts = train_cuts.filter(remove_short_and_long_utt)
 

egs/wenetspeech/ASR/pruned_transducer_stateless5/train.py

@@ -1006,15 +1006,41 @@ def run(rank, world_size, args):
     valid_cuts = wenetspeech.valid_cuts()
 
     def remove_short_and_long_utt(c: Cut):
-        # Keep only utterances with duration between 1 second and 15.0 seconds
+        # Keep only utterances with duration between 1 second and 10 seconds
         #
-        # Caution: There is a reason to select 15.0 here. Please see
+        # Caution: There is a reason to select 10.0 here. Please see
         # ../local/display_manifest_statistics.py
         #
         # You should use ../local/display_manifest_statistics.py to get
         # an utterance duration distribution for your dataset to select
         # the threshold
-        return 1.0 <= c.duration <= 15.0
+        if c.duration < 1.0 or c.duration > 10.0:
+            logging.warning(
+                f"Exclude cut with ID {c.id} from training. Duration: {c.duration}"
+            )
+            return False
+
+        # In pruned RNN-T, we require that T >= S
+        # where T is the number of feature frames after subsampling
+        # and S is the number of tokens in the utterance
+
+        # In ./conformer.py, the conv module uses the following expression
+        # for subsampling
+        T = ((c.num_frames - 1) // 2 - 1) // 2
+        tokens = c.supervisions[0].text.replace(" ", "")
+
+        if T < len(tokens):
+            logging.warning(
+                f"Exclude cut with ID {c.id} from training. "
+                f"Number of frames (before subsampling): {c.num_frames}. "
+                f"Number of frames (after subsampling): {T}. "
+                f"Text: {c.supervisions[0].text}. "
+                f"Tokens: {tokens}. "
+                f"Number of tokens: {len(tokens)}"
+            )
+            return False
+
+        return True
 
     train_cuts = train_cuts.filter(remove_short_and_long_utt)