text: # Copyright 2020 Huy Le Nguyen (@usimarit)
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  import tensorflow as tf
  
  
  @tf.function
  def ctc_loss(y_true, y_pred, input_length, label_length, blank):
      return tf.nn.ctc_loss(
          labels=tf.cast(y_true, tf.int32),
          logit_length=tf.cast(input_length, tf.int32),
          logits=tf.cast(y_pred, tf.float32),
          label_length=tf.cast(label_length, tf.int32),
          logits_time_major=False,
          blank_index=blank
      )
  