1. update to tf2.x for deep_speech (#8696)

Update to TF 2 for deep_speech

research/deep_speech/data/dataset.py

@@ -71,8 +71,8 @@ class DatasetConfig(object):
     """
 
     self.audio_config = audio_config
-    assert tf.gfile.Exists(data_path)
-    assert tf.gfile.Exists(vocab_file_path)
+    assert tf.io.gfile.exists(data_path)
+    assert tf.io.gfile.exists(vocab_file_path)
     self.data_path = data_path
     self.vocab_file_path = vocab_file_path
     self.sortagrad = sortagrad
@@ -125,8 +125,8 @@ def _preprocess_data(file_path):
     A list of tuples (wav_filename, wav_filesize, transcript) sorted by
     file_size.
   """
-  tf.logging.info("Loading data set {}".format(file_path))
-  with tf.gfile.Open(file_path, "r") as f:
+  tf.compat.v1.logging.info("Loading data set {}".format(file_path))
+  with tf.io.gfile.GFile(file_path, "r") as f:
     lines = f.read().splitlines()
   # Skip the csv header in lines[0].
   lines = lines[1:]

research/deep_speech/data/download.py

@@ -59,13 +59,13 @@ def download_and_extract(directory, url):
     url: the url to download the data file.
   """
 
-  if not tf.gfile.Exists(directory):
-    tf.gfile.MakeDirs(directory)
+  if not tf.io.gfile.exists(directory):
+    tf.io.gfile.makedirs(directory)
 
   _, tar_filepath = tempfile.mkstemp(suffix=".tar.gz")
 
   try:
-    tf.logging.info("Downloading %s to %s" % (url, tar_filepath))
+    tf.compat.v1.logging.info("Downloading %s to %s" % (url, tar_filepath))
 
     def _progress(count, block_size, total_size):
       sys.stdout.write("\r>> Downloading {} {:.1f}%".format(
@@ -75,12 +75,12 @@ def download_and_extract(directory, url):
     urllib.request.urlretrieve(url, tar_filepath, _progress)
     print()
     statinfo = os.stat(tar_filepath)
-    tf.logging.info(
+    tf.compat.v1.logging.info(
         "Successfully downloaded %s, size(bytes): %d" % (url, statinfo.st_size))
     with tarfile.open(tar_filepath, "r") as tar:
       tar.extractall(directory)
   finally:
-    tf.gfile.Remove(tar_filepath)
+    tf.io.gfile.remove(tar_filepath)
 
 
 def convert_audio_and_split_transcript(input_dir, source_name, target_name,
@@ -112,18 +112,18 @@ def convert_audio_and_split_transcript(input_dir, source_name, target_name,
     output_file: the name of the newly generated csv file. e.g. test-clean.csv
   """
 
-  tf.logging.info("Preprocessing audio and transcript for %s" % source_name)
+  tf.compat.v1.logging.info("Preprocessing audio and transcript for %s" % source_name)
   source_dir = os.path.join(input_dir, source_name)
   target_dir = os.path.join(input_dir, target_name)
 
-  if not tf.gfile.Exists(target_dir):
-    tf.gfile.MakeDirs(target_dir)
+  if not tf.io.gfile.exists(target_dir):
+    tf.io.gfile.makedirs(target_dir)
 
   files = []
   tfm = Transformer()
   # Convert all FLAC file into WAV format. At the same time, generate the csv
   # file.
-  for root, _, filenames in tf.gfile.Walk(source_dir):
+  for root, _, filenames in tf.io.gfile.walk(source_dir):
     for filename in fnmatch.filter(filenames, "*.trans.txt"):
       trans_file = os.path.join(root, filename)
       with codecs.open(trans_file, "r", "utf-8") as fin:
@@ -137,7 +137,7 @@ def convert_audio_and_split_transcript(input_dir, source_name, target_name,
           # Convert FLAC to WAV.
           flac_file = os.path.join(root, seqid + ".flac")
           wav_file = os.path.join(target_dir, seqid + ".wav")
-          if not tf.gfile.Exists(wav_file):
+          if not tf.io.gfile.exists(wav_file):
             tfm.build(flac_file, wav_file)
           wav_filesize = os.path.getsize(wav_file)
 
@@ -149,7 +149,7 @@ def convert_audio_and_split_transcript(input_dir, source_name, target_name,
   df = pandas.DataFrame(
       data=files, columns=["wav_filename", "wav_filesize", "transcript"])
   df.to_csv(csv_file_path, index=False, sep="\t")
-  tf.logging.info("Successfully generated csv file {}".format(csv_file_path))
+  tf.compat.v1.logging.info("Successfully generated csv file {}".format(csv_file_path))
 
 
 def download_and_process_datasets(directory, datasets):
@@ -160,10 +160,10 @@ def download_and_process_datasets(directory, datasets):
     datasets: list of dataset names that will be downloaded and processed.
   """
 
-  tf.logging.info("Preparing LibriSpeech dataset: {}".format(
+  tf.compat.v1.logging.info("Preparing LibriSpeech dataset: {}".format(
       ",".join(datasets)))
   for dataset in datasets:
-    tf.logging.info("Preparing dataset %s", dataset)
+    tf.compat.v1.logging.info("Preparing dataset %s", dataset)
     dataset_dir = os.path.join(directory, dataset)
     download_and_extract(dataset_dir, LIBRI_SPEECH_URLS[dataset])
     convert_audio_and_split_transcript(
@@ -185,8 +185,8 @@ def define_data_download_flags():
 
 
 def main(_):
-  if not tf.gfile.Exists(FLAGS.data_dir):
-    tf.gfile.MakeDirs(FLAGS.data_dir)
+  if not tf.io.gfile.exists(FLAGS.data_dir):
+    tf.io.gfile.makedirs(FLAGS.data_dir)
 
   if FLAGS.train_only:
     download_and_process_datasets(
@@ -202,7 +202,7 @@ def main(_):
 
 
 if __name__ == "__main__":
-  tf.logging.set_verbosity(tf.logging.INFO)
+  tf.compat.v1.logging.set_verbosity(tf.compat.v1.logging.INFO)
   define_data_download_flags()
   FLAGS = absl_flags.FLAGS
   absl_app.run(main)

research/deep_speech/deep_speech.py

@@ -61,25 +61,10 @@ def compute_length_after_conv(max_time_steps, ctc_time_steps, input_length):
   Returns:
     the ctc_input_length after convolution layer.
   """
-  ctc_input_length = tf.to_float(tf.multiply(
-      input_length, ctc_time_steps))
-  return tf.to_int32(tf.floordiv(
-      ctc_input_length, tf.to_float(max_time_steps)))
-
-
-def ctc_loss(label_length, ctc_input_length, labels, logits):
-  """Computes the ctc loss for the current batch of predictions."""
-  label_length = tf.to_int32(tf.squeeze(label_length))
-  ctc_input_length = tf.to_int32(tf.squeeze(ctc_input_length))
-  sparse_labels = tf.to_int32(
-      tf.keras.backend.ctc_label_dense_to_sparse(labels, label_length))
-  y_pred = tf.log(tf.transpose(
-      logits, perm=[1, 0, 2]) + tf.keras.backend.epsilon())
-
-  return tf.expand_dims(
-      tf.nn.ctc_loss(labels=sparse_labels, inputs=y_pred,
-                     sequence_length=ctc_input_length),
-      axis=1)
+  ctc_input_length = tf.cast(tf.multiply(
+      input_length, ctc_time_steps), dtype=tf.float32)
+  return tf.cast(tf.math.floordiv(
+      ctc_input_length, tf.cast(max_time_steps, dtype=tf.float32)), dtype=tf.int32)
 
 
 def evaluate_model(estimator, speech_labels, entries, input_fn_eval):
@@ -123,11 +108,11 @@ def evaluate_model(estimator, speech_labels, entries, input_fn_eval):
   total_cer /= num_of_examples
   total_wer /= num_of_examples
 
-  global_step = estimator.get_variable_value(tf.GraphKeys.GLOBAL_STEP)
+  global_step = estimator.get_variable_value(tf.compat.v1.GraphKeys.GLOBAL_STEP)
   eval_results = {
       _WER_KEY: total_wer,
       _CER_KEY: total_cer,
-      tf.GraphKeys.GLOBAL_STEP: global_step,
+      tf.compat.v1.GraphKeys.GLOBAL_STEP: global_step,
   }
 
   return eval_results
@@ -163,7 +148,7 @@ def model_fn(features, labels, mode, params):
     logits = model(features, training=False)
     predictions = {
         "classes": tf.argmax(logits, axis=2),
-        "probabilities": tf.nn.softmax(logits),
+        "probabilities": logits,
         "logits": logits
     }
     return tf.estimator.EstimatorSpec(
@@ -172,17 +157,16 @@ def model_fn(features, labels, mode, params):
 
   # In training mode.
   logits = model(features, training=True)
-  probs = tf.nn.softmax(logits)
   ctc_input_length = compute_length_after_conv(
-      tf.shape(features)[1], tf.shape(probs)[1], input_length)
+      tf.shape(features)[1], tf.shape(logits)[1], input_length)
   # Compute CTC loss
-  loss = tf.reduce_mean(ctc_loss(
-      label_length, ctc_input_length, labels, probs))
+  loss = tf.reduce_mean(tf.keras.backend.ctc_batch_cost(
+      labels, logits, ctc_input_length, label_length))
 
-  optimizer = tf.train.AdamOptimizer(learning_rate=flags_obj.learning_rate)
-  global_step = tf.train.get_or_create_global_step()
+  optimizer = tf.compat.v1.train.AdamOptimizer(learning_rate=flags_obj.learning_rate)
+  global_step = tf.compat.v1.train.get_or_create_global_step()
   minimize_op = optimizer.minimize(loss, global_step=global_step)
-  update_ops = tf.get_collection(tf.GraphKeys.UPDATE_OPS)
+  update_ops = tf.compat.v1.get_collection(tf.compat.v1.GraphKeys.UPDATE_OPS)
   # Create the train_op that groups both minimize_ops and update_ops
   train_op = tf.group(minimize_op, update_ops)
 
@@ -239,9 +223,9 @@ def per_device_batch_size(batch_size, num_gpus):
 
 def run_deep_speech(_):
   """Run deep speech training and eval loop."""
-  tf.set_random_seed(flags_obj.seed)
+  tf.compat.v1.set_random_seed(flags_obj.seed)
   # Data preprocessing
-  tf.logging.info("Data preprocessing...")
+  tf.compat.v1.logging.info("Data preprocessing...")
   train_speech_dataset = generate_dataset(flags_obj.train_data_dir)
   eval_speech_dataset = generate_dataset(flags_obj.eval_data_dir)
 
@@ -287,7 +271,7 @@ def run_deep_speech(_):
   total_training_cycle = (flags_obj.train_epochs //
                           flags_obj.epochs_between_evals)
   for cycle_index in range(total_training_cycle):
-    tf.logging.info("Starting a training cycle: %d/%d",
+    tf.compat.v1.logging.info("Starting a training cycle: %d/%d",
                     cycle_index + 1, total_training_cycle)
 
     # Perform batch_wise dataset shuffling
@@ -298,7 +282,7 @@ def run_deep_speech(_):
     estimator.train(input_fn=input_fn_train)
 
     # Evaluation
-    tf.logging.info("Starting to evaluate...")
+    tf.compat.v1.logging.info("Starting to evaluate...")
 
     eval_results = evaluate_model(
         estimator, eval_speech_dataset.speech_labels,
@@ -306,7 +290,7 @@ def run_deep_speech(_):
 
     # Log the WER and CER results.
     benchmark_logger.log_evaluation_result(eval_results)
-    tf.logging.info(
+    tf.compat.v1.logging.info(
         "Iteration {}: WER = {:.2f}, CER = {:.2f}".format(
             cycle_index + 1, eval_results[_WER_KEY], eval_results[_CER_KEY]))
 
@@ -425,7 +409,7 @@ def main(_):
 
 
 if __name__ == "__main__":
-  tf.logging.set_verbosity(tf.logging.INFO)
+  tf.compat.v1.logging.set_verbosity(tf.compat.v1.logging.INFO)
   define_deep_speech_flags()
   flags_obj = flags.FLAGS
   absl_app.run(main)

research/deep_speech/deep_speech_model.py

@@ -22,9 +22,9 @@ import tensorflow as tf
 
 # Supported rnn cells.
 SUPPORTED_RNNS = {
-    "lstm": tf.contrib.rnn.BasicLSTMCell,
-    "rnn": tf.contrib.rnn.RNNCell,
-    "gru": tf.contrib.rnn.GRUCell,
+    "lstm": tf.keras.layers.LSTMCell,
+    "rnn": tf.keras.layers.SimpleRNNCell,
+    "gru": tf.keras.layers.GRUCell,
 }
 
 # Parameters for batch normalization.
@@ -53,9 +53,8 @@ def batch_norm(inputs, training):
   Returns:
     tensor output from batch norm layer.
   """
-  return tf.layers.batch_normalization(
-      inputs=inputs, momentum=_BATCH_NORM_DECAY, epsilon=_BATCH_NORM_EPSILON,
-      fused=True, training=training)
+  return tf.keras.layers.BatchNormalization(
+      momentum=_BATCH_NORM_DECAY, epsilon=_BATCH_NORM_EPSILON)(inputs, training=training)
 
 
 def _conv_bn_layer(inputs, padding, filters, kernel_size, strides, layer_id,
@@ -81,10 +80,10 @@ def _conv_bn_layer(inputs, padding, filters, kernel_size, strides, layer_id,
   inputs = tf.pad(
       inputs,
       [[0, 0], [padding[0], padding[0]], [padding[1], padding[1]], [0, 0]])
-  inputs = tf.layers.conv2d(
-      inputs=inputs, filters=filters, kernel_size=kernel_size, strides=strides,
+  inputs = tf.keras.layers.Conv2D(
+      filters=filters, kernel_size=kernel_size, strides=strides,
       padding="valid", use_bias=False, activation=tf.nn.relu6,
-      name="cnn_{}".format(layer_id))
+      name="cnn_{}".format(layer_id))(inputs)
   return batch_norm(inputs, training)
 
 
@@ -109,24 +108,16 @@ def _rnn_layer(inputs, rnn_cell, rnn_hidden_size, layer_id, is_batch_norm,
   if is_batch_norm:
     inputs = batch_norm(inputs, training)
 
-  # Construct forward/backward RNN cells.
-  fw_cell = rnn_cell(num_units=rnn_hidden_size,
-                     name="rnn_fw_{}".format(layer_id))
-  bw_cell = rnn_cell(num_units=rnn_hidden_size,
-                     name="rnn_bw_{}".format(layer_id))
-
   if is_bidirectional:
-    outputs, _ = tf.nn.bidirectional_dynamic_rnn(
-        cell_fw=fw_cell, cell_bw=bw_cell, inputs=inputs, dtype=tf.float32,
-        swap_memory=True)
-    rnn_outputs = tf.concat(outputs, -1)
+    rnn_outputs = tf.keras.layers.Bidirectional(
+        tf.keras.layers.RNN(rnn_cell(rnn_hidden_size),
+                            return_sequences=True))(inputs)
   else:
-    rnn_outputs = tf.nn.dynamic_rnn(
-        fw_cell, inputs, dtype=tf.float32, swap_memory=True)
+    rnn_outputs = tf.keras.layers.RNN(
+        rnn_cell(rnn_hidden_size), return_sequences=True)(inputs)
 
   return rnn_outputs
 
-
 class DeepSpeech2(object):
   """Define DeepSpeech2 model."""
 
@@ -179,7 +170,8 @@ class DeepSpeech2(object):
 
     # FC layer with batch norm.
     inputs = batch_norm(inputs, training)
-    logits = tf.layers.dense(inputs, self.num_classes, use_bias=self.use_bias)
+    logits = tf.keras.layers.Dense(
+        self.num_classes, use_bias=self.use_bias, activation="softmax")(inputs)
 
     return logits