Merge pull request #817 from PaddlePaddle/ctc

export ctc grad norm config

deepspeech/models/ds2/deepspeech2.py

@@ -128,8 +128,8 @@ class DeepSpeech2Model(nn.Layer):
                 num_rnn_layers=3,  #Number of stacking RNN layers.
                 rnn_layer_size=1024,  #RNN layer size (number of RNN cells).
                 use_gru=True,  #Use gru if set True. Use simple rnn if set False.
-                share_rnn_weights=True  #Whether to share input-hidden weights between forward and backward directional RNNs.Notice that for GRU, weight sharing is not supported.
-            ))
+                share_rnn_weights=True,  #Whether to share input-hidden weights between forward and backward directional RNNs.Notice that for GRU, weight sharing is not supported.
+                ctc_grad_norm_type='instance', ))
         if config is not None:
             config.merge_from_other_cfg(default)
         return default
@@ -142,7 +142,8 @@ class DeepSpeech2Model(nn.Layer):
                  rnn_size=1024,
                  use_gru=False,
                  share_rnn_weights=True,
-                 blank_id=0):
+                 blank_id=0,
+                 ctc_grad_norm_type='instance'):
         super().__init__()
         self.encoder = CRNNEncoder(
             feat_size=feat_size,
@@ -160,7 +161,8 @@ class DeepSpeech2Model(nn.Layer):
             blank_id=blank_id,
             dropout_rate=0.0,
             reduction=True,  # sum
-            batch_average=True)  # sum / batch_size
+            batch_average=True,  # sum / batch_size
+            grad_norm_type=ctc_grad_norm_type)
 
     def forward(self, audio, audio_len, text, text_len):
         """Compute Model loss

deepspeech/models/ds2_online/deepspeech2.py

@@ -289,7 +289,8 @@ class DeepSpeech2ModelOnline(nn.Layer):
             blank_id=blank_id,
             dropout_rate=0.0,
             reduction=True,  # sum
-            batch_average=True)  # sum / batch_size
+            batch_average=True,  # sum / batch_size
+            grad_norm_type='instance')
 
     def forward(self, audio, audio_len, text, text_len):
         """Compute Model loss

deepspeech/models/u2.py

@@ -864,7 +864,8 @@ class U2Model(U2BaseModel):
             blank_id=0,
             dropout_rate=0.0,
             reduction=True,  # sum
-            batch_average=True)  # sum / batch_size
+            batch_average=True,  # sum / batch_size
+            grad_norm_type='instance')
 
         return vocab_size, encoder, decoder, ctc
 

deepspeech/models/u2_st.py

@@ -649,7 +649,8 @@ class U2STModel(U2STBaseModel):
                 blank_id=0,
                 dropout_rate=0.0,
                 reduction=True,  # sum
-                batch_average=True)  # sum / batch_size
+                batch_average=True,  # sum / batch_size
+                grad_norm_type='instance')
 
             return vocab_size, encoder, (st_decoder, decoder, ctc)
         else:

deepspeech/modules/ctc.py

@@ -39,7 +39,8 @@ class CTCDecoder(nn.Layer):
                  blank_id=0,
                  dropout_rate: float=0.0,
                  reduction: bool=True,
-                 batch_average: bool=True):
+                 batch_average: bool=True,
+                 grad_norm_type: str="instance"):
         """CTC decoder
 
         Args:
@@ -48,6 +49,7 @@ class CTCDecoder(nn.Layer):
             dropout_rate (float): dropout rate (0.0 ~ 1.0)
             reduction (bool): reduce the CTC loss into a scalar, True for 'sum' or 'none'
             batch_average (bool): do batch dim wise average.
+            grad_norm_type (str): one of 'instance', 'batchsize', 'frame', None.
         """
         assert check_argument_types()
         super().__init__()
@@ -60,7 +62,8 @@ class CTCDecoder(nn.Layer):
         self.criterion = CTCLoss(
             blank=self.blank_id,
             reduction=reduction_type,
-            batch_average=batch_average)
+            batch_average=batch_average,
+            grad_norm_type=grad_norm_type)
 
         # CTCDecoder LM Score handle
         self._ext_scorer = None

deepspeech/modules/loss.py

@@ -23,11 +23,32 @@ __all__ = ['CTCLoss', "LabelSmoothingLoss"]
 
 
 class CTCLoss(nn.Layer):
-    def __init__(self, blank=0, reduction='sum', batch_average=False):
+    def __init__(self,
+                 blank=0,
+                 reduction='sum',
+                 batch_average=False,
+                 grad_norm_type=None):
         super().__init__()
         # last token id as blank id
         self.loss = nn.CTCLoss(blank=blank, reduction=reduction)
         self.batch_average = batch_average
+        logger.info(
+            f"CTCLoss Loss reduction: {reduction}, div-bs: {batch_average}")
+
+        # instance for norm_by_times
+        # batchsize for norm_by_batchsize
+        # frame for norm_by_total_logits_len
+        assert grad_norm_type in ('instance', 'batchsize', 'frame', None)
+        self.norm_by_times = False
+        self.norm_by_batchsize = False
+        self.norm_by_total_logits_len = False
+        logger.info(f"CTCLoss Grad Norm Type: {grad_norm_type}")
+        if grad_norm_type == 'instance':
+            self.norm_by_times = True
+        if grad_norm_type == 'batchsize':
+            self.norm_by_times = True
+        if grad_norm_type == 'frame':
+            self.norm_by_total_logits_len = True
 
     def forward(self, logits, ys_pad, hlens, ys_lens):
         """Compute CTC loss.
@@ -48,7 +69,13 @@ class CTCLoss(nn.Layer):
         logits = logits.transpose([1, 0, 2])
         ys_pad = ys_pad.astype(paddle.int32)
         loss = self.loss(
-            logits, ys_pad, hlens, ys_lens, norm_by_times=self.batch_average)
+            logits,
+            ys_pad,
+            hlens,
+            ys_lens,
+            norm_by_times=self.norm_by_times,
+            norm_by_batchsize=self.norm_by_batchsize,
+            norm_by_total_logits_len=self.norm_by_total_logits_len)
         if self.batch_average:
             # Batch-size average
             loss = loss / B

examples/aishell/s0/conf/deepspeech2.yaml

@@ -41,6 +41,7 @@ model:
   use_gru: True 
   share_rnn_weights: False
   blank_id: 0
+  ctc_grad_norm_type: instance
 
 training:
   n_epoch: 80

examples/aishell/s0/conf/deepspeech2_online.yaml

@@ -43,6 +43,7 @@ model:
   fc_layers_size_list: -1,
   use_gru: False 
   blank_id: 0
+  ctc_grad_norm_type: instance
   
 training:
   n_epoch: 50

examples/librispeech/s0/conf/deepspeech2.yaml

@@ -41,6 +41,7 @@ model:
   use_gru: False 
   share_rnn_weights: True
   blank_id: 0
+  ctc_grad_norm_type: instance
 
 training:
   n_epoch: 50

examples/librispeech/s0/conf/deepspeech2_online.yaml

@@ -43,6 +43,7 @@ model:
   fc_layers_size_list: 512, 256
   use_gru: False 
   blank_id: 0
+  ctc_grad_norm_type: instance
 
 training:
   n_epoch: 50

examples/tiny/s0/conf/deepspeech2.yaml

@@ -42,6 +42,7 @@ model:
   use_gru: False 
   share_rnn_weights: True 
   blank_id: 0
+  ctc_grad_norm_type: instance
 
 training:
   n_epoch: 10

examples/tiny/s0/conf/deepspeech2_online.yaml

@@ -44,6 +44,7 @@ model:
   fc_layers_size_list: 512, 256
   use_gru: True 
   blank_id: 0
+  ctc_grad_norm_type: instance
 
 training:
   n_epoch: 10