gauravkaila · December 5, 2017 18:46 · salman-ghauri · Aug 28, 2018 · anshkumar · Apr 30, 2019
diff --git a/exporter.py b/exporter.py
 # Copyright 2017 The TensorFlow Authors. All Rights Reserved.
 #
 # 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.
 # ==============================================================================

 """Functions to export object detection inference graph."""
 import logging
 import os
 import tempfile
 import tensorflow as tf
 from tensorflow.core.protobuf import rewriter_config_pb2
 from tensorflow.python import pywrap_tensorflow
 from tensorflow.python.client import session
 from tensorflow.python.framework import graph_util
 from tensorflow.python.platform import gfile
 from tensorflow.python.saved_model import signature_constants
 from tensorflow.python.training import saver as saver_lib
 from object_detection.builders import model_builder
 from object_detection.core import standard_fields as fields
 from object_detection.data_decoders import tf_example_decoder

 slim = tf.contrib.slim


 # TODO: Replace with freeze_graph.freeze_graph_with_def_protos when
 # newer version of Tensorflow becomes more common.
 def freeze_graph_with_def_protos(
    input_graph_def,
    input_saver_def,
    input_checkpoint,
    output_node_names,
    restore_op_name,
    filename_tensor_name,
    clear_devices,
    initializer_nodes,
    optimize_graph=True,
    variable_names_blacklist=''):
  """Converts all variables in a graph and checkpoint into constants."""
  del restore_op_name, filename_tensor_name  # Unused by updated loading code.

  # 'input_checkpoint' may be a prefix if we're using Saver V2 format
  if not saver_lib.checkpoint_exists(input_checkpoint):
    raise ValueError(
        'Input checkpoint "' + input_checkpoint + '" does not exist!')

  if not output_node_names:
    raise ValueError(
        'You must supply the name of a node to --output_node_names.')

  # Remove all the explicit device specifications for this node. This helps to
  # make the graph more portable.
  if clear_devices:
    for node in input_graph_def.node:
      node.device = ''

  with tf.Graph().as_default():
    tf.import_graph_def(input_graph_def, name='')

    if optimize_graph:
      logging.info('Graph Rewriter optimizations enabled')
      rewrite_options = rewriter_config_pb2.RewriterConfig(
          optimize_tensor_layout=True)
      rewrite_options.optimizers.append('pruning')
      rewrite_options.optimizers.append('constfold')
      rewrite_options.optimizers.append('layout')
      graph_options = tf.GraphOptions(
          rewrite_options=rewrite_options, infer_shapes=True)
    else:
      logging.info('Graph Rewriter optimizations disabled')
      graph_options = tf.GraphOptions()
    config = tf.ConfigProto(graph_options=graph_options)
    with session.Session(config=config) as sess:
      if input_saver_def:
        saver = saver_lib.Saver(saver_def=input_saver_def)
        saver.restore(sess, input_checkpoint)
      else:
        var_list = {}
        reader = pywrap_tensorflow.NewCheckpointReader(input_checkpoint)
        var_to_shape_map = reader.get_variable_to_shape_map()
        for key in var_to_shape_map:
          try:
            tensor = sess.graph.get_tensor_by_name(key + ':0')
          except KeyError:
            # This tensor doesn't exist in the graph (for example it's
            # 'global_step' or a similar housekeeping element) so skip it.
            continue
          var_list[key] = tensor
        saver = saver_lib.Saver(var_list=var_list)
        saver.restore(sess, input_checkpoint)
        if initializer_nodes:
          sess.run(initializer_nodes)

      variable_names_blacklist = (variable_names_blacklist.split(',') if
                                  variable_names_blacklist else None)
      output_graph_def = graph_util.convert_variables_to_constants(
          sess,
          input_graph_def,
          output_node_names.split(','),
          variable_names_blacklist=variable_names_blacklist)

  return output_graph_def


 def replace_variable_values_with_moving_averages(graph,
                                                 current_checkpoint_file,
                                                 new_checkpoint_file):
  """Replaces variable values in the checkpoint with their moving averages.

  If the current checkpoint has shadow variables maintaining moving averages of
  the variables defined in the graph, this function generates a new checkpoint
  where the variables contain the values of their moving averages.

  Args:
    graph: a tf.Graph object.
    current_checkpoint_file: a checkpoint containing both original variables and
      their moving averages.
    new_checkpoint_file: file path to write a new checkpoint.
  """
  with graph.as_default():
    variable_averages = tf.train.ExponentialMovingAverage(0.0)
    ema_variables_to_restore = variable_averages.variables_to_restore()
    with tf.Session() as sess:
      read_saver = tf.train.Saver(ema_variables_to_restore)
      read_saver.restore(sess, current_checkpoint_file)
      write_saver = tf.train.Saver()
      write_saver.save(sess, new_checkpoint_file)


 def _image_tensor_input_placeholder(input_shape=None):
  """Returns input placeholder and a 4-D uint8 image tensor."""
  if input_shape is None:
    input_shape = (None, None, None, 3)
  input_tensor = tf.placeholder(
      dtype=tf.uint8, shape=input_shape, name='image_tensor')
  return input_tensor, input_tensor


 def _tf_example_input_placeholder():
  """Returns input that accepts a batch of strings with tf examples.

  Returns:
    a tuple of input placeholder and the output decoded images.
  """
  batch_tf_example_placeholder = tf.placeholder(
      tf.string, shape=[None], name='tf_example')
  def decode(tf_example_string_tensor):
    tensor_dict = tf_example_decoder.TfExampleDecoder().decode(
        tf_example_string_tensor)
    image_tensor = tensor_dict[fields.InputDataFields.image]
    return image_tensor
  return (batch_tf_example_placeholder,
          tf.map_fn(decode,
                    elems=batch_tf_example_placeholder,
                    dtype=tf.uint8,
                    parallel_iterations=32,
                    back_prop=False))


 def _encoded_image_string_tensor_input_placeholder():
  """Returns input that accepts a batch of PNG or JPEG strings.

  Returns:
    a tuple of input placeholder and the output decoded images.
  """
  batch_image_str_placeholder = tf.placeholder(
      dtype=tf.string,
      shape=[None],
      name='encoded_image_string_tensor')
  def decode(encoded_image_string_tensor):
    image_tensor = tf.image.decode_image(encoded_image_string_tensor,
                                         channels=3)
    image_tensor.set_shape((None, None, 3))
    return image_tensor
  return (batch_image_str_placeholder,
          tf.map_fn(
              decode,
              elems=batch_image_str_placeholder,
              dtype=tf.uint8,
              parallel_iterations=32,
              back_prop=False))


 input_placeholder_fn_map = {
    'image_tensor': _image_tensor_input_placeholder,
    'encoded_image_string_tensor':
    _encoded_image_string_tensor_input_placeholder,
    'tf_example': _tf_example_input_placeholder,
 }


 def _add_output_tensor_nodes(postprocessed_tensors,
                             output_collection_name='inference_op'):
  """Adds output nodes for detection boxes and scores.

  Adds the following nodes for output tensors -
    * num_detections: float32 tensor of shape [batch_size].
    * detection_boxes: float32 tensor of shape [batch_size, num_boxes, 4]
      containing detected boxes.
    * detection_scores: float32 tensor of shape [batch_size, num_boxes]
      containing scores for the detected boxes.
    * detection_classes: float32 tensor of shape [batch_size, num_boxes]
      containing class predictions for the detected boxes.
    * detection_masks: (Optional) float32 tensor of shape
      [batch_size, num_boxes, mask_height, mask_width] containing masks for each
      detection box.

  Args:
    postprocessed_tensors: a dictionary containing the following fields
      'detection_boxes': [batch, max_detections, 4]
      'detection_scores': [batch, max_detections]
      'detection_classes': [batch, max_detections]
      'detection_masks': [batch, max_detections, mask_height, mask_width]
        (optional).
      'num_detections': [batch]
    output_collection_name: Name of collection to add output tensors to.

  Returns:
    A tensor dict containing the added output tensor nodes.
  """
  label_id_offset = 1
  boxes = postprocessed_tensors.get('detection_boxes')
  scores = postprocessed_tensors.get('detection_scores')
  classes = postprocessed_tensors.get('detection_classes') + label_id_offset
  masks = postprocessed_tensors.get('detection_masks')
  num_detections = postprocessed_tensors.get('num_detections')
  outputs = {}
  outputs['detection_boxes'] = tf.identity(boxes, name='detection_boxes')
  outputs['detection_scores'] = tf.identity(scores, name='detection_scores')
  outputs['detection_classes'] = tf.identity(classes, name='detection_classes')
  outputs['num_detections'] = tf.identity(num_detections, name='num_detections')
  if masks is not None:
    outputs['detection_masks'] = tf.identity(masks, name='detection_masks')
  for output_key in outputs:
    tf.add_to_collection(output_collection_name, outputs[output_key])
  if masks is not None:
    tf.add_to_collection(output_collection_name, outputs['detection_masks'])
  return outputs


 # def _write_frozen_graph(frozen_graph_path, frozen_graph_def):
 #   """Writes frozen graph to disk.
 #
 #   Args:
 #     frozen_graph_path: Path to write inference graph.
 #     frozen_graph_def: tf.GraphDef holding frozen graph.
 #   """
 #   with gfile.GFile(frozen_graph_path, 'wb') as f:
 #     f.write(frozen_graph_def.SerializeToString())
 #   logging.info('%d ops in the final graph.', len(frozen_graph_def.node))

 def _write_saved_model(saved_model_path,
                       trained_checkpoint_prefix,
                       inputs,
                       outputs):
  """Writes SavedModel to disk.
  Args:
    saved_model_path: Path to write SavedModel.
    trained_checkpoint_prefix: path to trained_checkpoint_prefix.
    inputs: The input image tensor to use for detection.
    outputs: A tensor dictionary containing the outputs of a DetectionModel.
  """
  saver = tf.train.Saver()
  with session.Session() as sess:
    saver.restore(sess, trained_checkpoint_prefix)
    builder = tf.saved_model.builder.SavedModelBuilder(saved_model_path)

    tensor_info_inputs = {
          'inputs': tf.saved_model.utils.build_tensor_info(inputs)}
    tensor_info_outputs = {}
    for k, v in outputs.items():
      tensor_info_outputs[k] = tf.saved_model.utils.build_tensor_info(v)

    detection_signature = (
        tf.saved_model.signature_def_utils.build_signature_def(
              inputs=tensor_info_inputs,
              outputs=tensor_info_outputs,
              method_name=signature_constants.PREDICT_METHOD_NAME))

    builder.add_meta_graph_and_variables(
          sess, [tf.saved_model.tag_constants.SERVING],
          signature_def_map={
              'detection_signature':
                  detection_signature,
              signature_constants.DEFAULT_SERVING_SIGNATURE_DEF_KEY:
                  detection_signature,
          },
      )
    builder.save()

 def _export_inference_graph(input_type,
                            detection_model,
                            use_moving_averages,
                            trained_checkpoint_prefix,
                            output_directory,
                            additional_output_tensor_names=None,
                            input_shape=None,
                            optimize_graph=True,
                            output_collection_name='inference_op'):
  """Export helper."""
  #tf.gfile.MakeDirs(output_directory)
  #frozen_graph_path = os.path.join(output_directory,
  #                                 'frozen_inference_graph.pb')
  #saved_model_path = os.path.join(output_directory, 'saved_model')
  saved_model_path = output_directory

  if input_type not in input_placeholder_fn_map:
    raise ValueError('Unknown input type: {}'.format(input_type))
  placeholder_args = {}
  if input_shape is not None:
    if input_type != 'image_tensor':
      raise ValueError('Can only specify input shape for `image_tensor` '
                       'inputs.')
    placeholder_args['input_shape'] = input_shape
  placeholder_tensor, input_tensors = input_placeholder_fn_map[input_type](
      **placeholder_args)
  inputs = tf.to_float(input_tensors)
  preprocessed_inputs = detection_model.preprocess(inputs)
  output_tensors = detection_model.predict(preprocessed_inputs)
  postprocessed_tensors = detection_model.postprocess(output_tensors)
  outputs = _add_output_tensor_nodes(postprocessed_tensors,
                                     output_collection_name)
  # Add global step to the graph.
  slim.get_or_create_global_step()

  if use_moving_averages:
    temp_checkpoint_file = tempfile.NamedTemporaryFile()
    replace_variable_values_with_moving_averages(
        tf.get_default_graph(), trained_checkpoint_prefix,
        temp_checkpoint_file.name)
    checkpoint_to_use = temp_checkpoint_file.name
  else:
    checkpoint_to_use = trained_checkpoint_prefix

  saver = tf.train.Saver()
  input_saver_def = saver.as_saver_def()

  if additional_output_tensor_names is not None:
    output_node_names = ','.join(outputs.keys()+additional_output_tensor_names)
  else:
    output_node_names = ','.join(outputs.keys())

  frozen_graph_def = freeze_graph_with_def_protos(
      input_graph_def=tf.get_default_graph().as_graph_def(),
      input_saver_def=input_saver_def,
      input_checkpoint=checkpoint_to_use,
      output_node_names=output_node_names,
      restore_op_name='save/restore_all',
      filename_tensor_name='save/Const:0',
      clear_devices=True,
      optimize_graph=optimize_graph,
      initializer_nodes='')
  #_write_frozen_graph(frozen_graph_path, frozen_graph_def)
  _write_saved_model(saved_model_path, trained_checkpoint_prefix,
                     placeholder_tensor, outputs)


 def export_inference_graph(input_type,
                           pipeline_config,
                           trained_checkpoint_prefix,
                           output_directory,
                           input_shape=None,
                           optimize_graph=True,
                           output_collection_name='inference_op',
                           additional_output_tensor_names=None):
  """Exports inference graph for the model specified in the pipeline config.

  Args:
    input_type: Type of input for the graph. Can be one of [`image_tensor`,
      `tf_example`].
    pipeline_config: pipeline_pb2.TrainAndEvalPipelineConfig proto.
    trained_checkpoint_prefix: Path to the trained checkpoint file.
    output_directory: Path to write outputs.
    input_shape: Sets a fixed shape for an `image_tensor` input. If not
      specified, will default to [None, None, None, 3].
    optimize_graph: Whether to optimize graph using Grappler.
    output_collection_name: Name of collection to add output tensors to.
      If None, does not add output tensors to a collection.
    additional_output_tensor_names: list of additional output
    tensors to include in the frozen graph.
  """
  detection_model = model_builder.build(pipeline_config.model,
                                        is_training=False)
  _export_inference_graph(input_type, detection_model,
                          pipeline_config.eval_config.use_moving_averages,
                          trained_checkpoint_prefix,
                          output_directory, additional_output_tensor_names,
                          input_shape, optimize_graph, output_collection_name)
	# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
	#
	# 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.
	# ==============================================================================

	"""Functions to export object detection inference graph."""
	import logging
	import os
	import tempfile
	import tensorflow as tf
	from tensorflow.core.protobuf import rewriter_config_pb2
	from tensorflow.python import pywrap_tensorflow
	from tensorflow.python.client import session
	from tensorflow.python.framework import graph_util
	from tensorflow.python.platform import gfile
	from tensorflow.python.saved_model import signature_constants
	from tensorflow.python.training import saver as saver_lib
	from object_detection.builders import model_builder
	from object_detection.core import standard_fields as fields
	from object_detection.data_decoders import tf_example_decoder

	slim = tf.contrib.slim


	# TODO: Replace with freeze_graph.freeze_graph_with_def_protos when
	# newer version of Tensorflow becomes more common.
	def freeze_graph_with_def_protos(
	input_graph_def,
	input_saver_def,
	input_checkpoint,
	output_node_names,
	restore_op_name,
	filename_tensor_name,
	clear_devices,
	initializer_nodes,
	optimize_graph=True,
	variable_names_blacklist=''):
	"""Converts all variables in a graph and checkpoint into constants."""
	del restore_op_name, filename_tensor_name # Unused by updated loading code.

	# 'input_checkpoint' may be a prefix if we're using Saver V2 format
	if not saver_lib.checkpoint_exists(input_checkpoint):
	raise ValueError(
	'Input checkpoint "' + input_checkpoint + '" does not exist!')

	if not output_node_names:
	raise ValueError(
	'You must supply the name of a node to --output_node_names.')

	# Remove all the explicit device specifications for this node. This helps to
	# make the graph more portable.
	if clear_devices:
	for node in input_graph_def.node:
	node.device = ''

	with tf.Graph().as_default():
	tf.import_graph_def(input_graph_def, name='')

	if optimize_graph:
	logging.info('Graph Rewriter optimizations enabled')
	rewrite_options = rewriter_config_pb2.RewriterConfig(
	optimize_tensor_layout=True)
	rewrite_options.optimizers.append('pruning')
	rewrite_options.optimizers.append('constfold')
	rewrite_options.optimizers.append('layout')
	graph_options = tf.GraphOptions(
	rewrite_options=rewrite_options, infer_shapes=True)
	else:
	logging.info('Graph Rewriter optimizations disabled')
	graph_options = tf.GraphOptions()
	config = tf.ConfigProto(graph_options=graph_options)
	with session.Session(config=config) as sess:
	if input_saver_def:
	saver = saver_lib.Saver(saver_def=input_saver_def)
	saver.restore(sess, input_checkpoint)
	else:
	var_list = {}
	reader = pywrap_tensorflow.NewCheckpointReader(input_checkpoint)
	var_to_shape_map = reader.get_variable_to_shape_map()
	for key in var_to_shape_map:
	try:
	tensor = sess.graph.get_tensor_by_name(key + ':0')
	except KeyError:
	# This tensor doesn't exist in the graph (for example it's
	# 'global_step' or a similar housekeeping element) so skip it.
	continue
	var_list[key] = tensor
	saver = saver_lib.Saver(var_list=var_list)
	saver.restore(sess, input_checkpoint)
	if initializer_nodes:
	sess.run(initializer_nodes)

	variable_names_blacklist = (variable_names_blacklist.split(',') if
	variable_names_blacklist else None)
	output_graph_def = graph_util.convert_variables_to_constants(
	sess,
	input_graph_def,
	output_node_names.split(','),
	variable_names_blacklist=variable_names_blacklist)

	return output_graph_def


	def replace_variable_values_with_moving_averages(graph,
	current_checkpoint_file,
	new_checkpoint_file):
	"""Replaces variable values in the checkpoint with their moving averages.

	If the current checkpoint has shadow variables maintaining moving averages of
	the variables defined in the graph, this function generates a new checkpoint
	where the variables contain the values of their moving averages.

	Args:
	graph: a tf.Graph object.
	current_checkpoint_file: a checkpoint containing both original variables and
	their moving averages.
	new_checkpoint_file: file path to write a new checkpoint.
	"""
	with graph.as_default():
	variable_averages = tf.train.ExponentialMovingAverage(0.0)
	ema_variables_to_restore = variable_averages.variables_to_restore()
	with tf.Session() as sess:
	read_saver = tf.train.Saver(ema_variables_to_restore)
	read_saver.restore(sess, current_checkpoint_file)
	write_saver = tf.train.Saver()
	write_saver.save(sess, new_checkpoint_file)


	def _image_tensor_input_placeholder(input_shape=None):
	"""Returns input placeholder and a 4-D uint8 image tensor."""
	if input_shape is None:
	input_shape = (None, None, None, 3)
	input_tensor = tf.placeholder(
	dtype=tf.uint8, shape=input_shape, name='image_tensor')
	return input_tensor, input_tensor


	def _tf_example_input_placeholder():
	"""Returns input that accepts a batch of strings with tf examples.

	Returns:
	a tuple of input placeholder and the output decoded images.
	"""
	batch_tf_example_placeholder = tf.placeholder(
	tf.string, shape=[None], name='tf_example')
	def decode(tf_example_string_tensor):
	tensor_dict = tf_example_decoder.TfExampleDecoder().decode(
	tf_example_string_tensor)
	image_tensor = tensor_dict[fields.InputDataFields.image]
	return image_tensor
	return (batch_tf_example_placeholder,
	tf.map_fn(decode,
	elems=batch_tf_example_placeholder,
	dtype=tf.uint8,
	parallel_iterations=32,
	back_prop=False))


	def _encoded_image_string_tensor_input_placeholder():
	"""Returns input that accepts a batch of PNG or JPEG strings.

	Returns:
	a tuple of input placeholder and the output decoded images.
	"""
	batch_image_str_placeholder = tf.placeholder(
	dtype=tf.string,
	shape=[None],
	name='encoded_image_string_tensor')
	def decode(encoded_image_string_tensor):
	image_tensor = tf.image.decode_image(encoded_image_string_tensor,
	channels=3)
	image_tensor.set_shape((None, None, 3))
	return image_tensor
	return (batch_image_str_placeholder,
	tf.map_fn(
	decode,
	elems=batch_image_str_placeholder,
	dtype=tf.uint8,
	parallel_iterations=32,
	back_prop=False))


	input_placeholder_fn_map = {
	'image_tensor': _image_tensor_input_placeholder,
	'encoded_image_string_tensor':
	_encoded_image_string_tensor_input_placeholder,
	'tf_example': _tf_example_input_placeholder,
	}


	def _add_output_tensor_nodes(postprocessed_tensors,
	output_collection_name='inference_op'):
	"""Adds output nodes for detection boxes and scores.

	Adds the following nodes for output tensors -
	* num_detections: float32 tensor of shape [batch_size].
	* detection_boxes: float32 tensor of shape [batch_size, num_boxes, 4]
	containing detected boxes.
	* detection_scores: float32 tensor of shape [batch_size, num_boxes]
	containing scores for the detected boxes.
	* detection_classes: float32 tensor of shape [batch_size, num_boxes]
	containing class predictions for the detected boxes.
	* detection_masks: (Optional) float32 tensor of shape
	[batch_size, num_boxes, mask_height, mask_width] containing masks for each
	detection box.

	Args:
	postprocessed_tensors: a dictionary containing the following fields
	'detection_boxes': [batch, max_detections, 4]
	'detection_scores': [batch, max_detections]
	'detection_classes': [batch, max_detections]
	'detection_masks': [batch, max_detections, mask_height, mask_width]
	(optional).
	'num_detections': [batch]
	output_collection_name: Name of collection to add output tensors to.

	Returns:
	A tensor dict containing the added output tensor nodes.
	"""
	label_id_offset = 1
	boxes = postprocessed_tensors.get('detection_boxes')
	scores = postprocessed_tensors.get('detection_scores')
	classes = postprocessed_tensors.get('detection_classes') + label_id_offset
	masks = postprocessed_tensors.get('detection_masks')
	num_detections = postprocessed_tensors.get('num_detections')
	outputs = {}
	outputs['detection_boxes'] = tf.identity(boxes, name='detection_boxes')
	outputs['detection_scores'] = tf.identity(scores, name='detection_scores')
	outputs['detection_classes'] = tf.identity(classes, name='detection_classes')
	outputs['num_detections'] = tf.identity(num_detections, name='num_detections')
	if masks is not None:
	outputs['detection_masks'] = tf.identity(masks, name='detection_masks')
	for output_key in outputs:
	tf.add_to_collection(output_collection_name, outputs[output_key])
	if masks is not None:
	tf.add_to_collection(output_collection_name, outputs['detection_masks'])
	return outputs


	# def _write_frozen_graph(frozen_graph_path, frozen_graph_def):
	# """Writes frozen graph to disk.
	#
	# Args:
	# frozen_graph_path: Path to write inference graph.
	# frozen_graph_def: tf.GraphDef holding frozen graph.
	# """
	# with gfile.GFile(frozen_graph_path, 'wb') as f:
	# f.write(frozen_graph_def.SerializeToString())
	# logging.info('%d ops in the final graph.', len(frozen_graph_def.node))

	def _write_saved_model(saved_model_path,
	trained_checkpoint_prefix,
	inputs,
	outputs):
	"""Writes SavedModel to disk.
	Args:
	saved_model_path: Path to write SavedModel.
	trained_checkpoint_prefix: path to trained_checkpoint_prefix.
	inputs: The input image tensor to use for detection.
	outputs: A tensor dictionary containing the outputs of a DetectionModel.
	"""
	saver = tf.train.Saver()
	with session.Session() as sess:
	saver.restore(sess, trained_checkpoint_prefix)
	builder = tf.saved_model.builder.SavedModelBuilder(saved_model_path)

	tensor_info_inputs = {
	'inputs': tf.saved_model.utils.build_tensor_info(inputs)}
	tensor_info_outputs = {}
	for k, v in outputs.items():
	tensor_info_outputs[k] = tf.saved_model.utils.build_tensor_info(v)

	detection_signature = (
	tf.saved_model.signature_def_utils.build_signature_def(
	inputs=tensor_info_inputs,
	outputs=tensor_info_outputs,
	method_name=signature_constants.PREDICT_METHOD_NAME))

	builder.add_meta_graph_and_variables(
	sess, [tf.saved_model.tag_constants.SERVING],
	signature_def_map={
	'detection_signature':
	detection_signature,
	signature_constants.DEFAULT_SERVING_SIGNATURE_DEF_KEY:
	detection_signature,
	},
	)
	builder.save()

	def _export_inference_graph(input_type,
	detection_model,
	use_moving_averages,
	trained_checkpoint_prefix,
	output_directory,
	additional_output_tensor_names=None,
	input_shape=None,
	optimize_graph=True,
	output_collection_name='inference_op'):
	"""Export helper."""
	#tf.gfile.MakeDirs(output_directory)
	#frozen_graph_path = os.path.join(output_directory,
	# 'frozen_inference_graph.pb')
	#saved_model_path = os.path.join(output_directory, 'saved_model')
	saved_model_path = output_directory

	if input_type not in input_placeholder_fn_map:
	raise ValueError('Unknown input type: {}'.format(input_type))
	placeholder_args = {}
	if input_shape is not None:
	if input_type != 'image_tensor':
	raise ValueError('Can only specify input shape for `image_tensor` '
	'inputs.')
	placeholder_args['input_shape'] = input_shape
	placeholder_tensor, input_tensors = input_placeholder_fn_map[input_type](
	**placeholder_args)
	inputs = tf.to_float(input_tensors)
	preprocessed_inputs = detection_model.preprocess(inputs)
	output_tensors = detection_model.predict(preprocessed_inputs)
	postprocessed_tensors = detection_model.postprocess(output_tensors)
	outputs = _add_output_tensor_nodes(postprocessed_tensors,
	output_collection_name)
	# Add global step to the graph.
	slim.get_or_create_global_step()

	if use_moving_averages:
	temp_checkpoint_file = tempfile.NamedTemporaryFile()
	replace_variable_values_with_moving_averages(
	tf.get_default_graph(), trained_checkpoint_prefix,
	temp_checkpoint_file.name)
	checkpoint_to_use = temp_checkpoint_file.name
	else:
	checkpoint_to_use = trained_checkpoint_prefix

	saver = tf.train.Saver()
	input_saver_def = saver.as_saver_def()

	if additional_output_tensor_names is not None:
	output_node_names = ','.join(outputs.keys()+additional_output_tensor_names)
	else:
	output_node_names = ','.join(outputs.keys())

	frozen_graph_def = freeze_graph_with_def_protos(
	input_graph_def=tf.get_default_graph().as_graph_def(),
	input_saver_def=input_saver_def,
	input_checkpoint=checkpoint_to_use,
	output_node_names=output_node_names,
	restore_op_name='save/restore_all',
	filename_tensor_name='save/Const:0',
	clear_devices=True,
	optimize_graph=optimize_graph,
	initializer_nodes='')
	#_write_frozen_graph(frozen_graph_path, frozen_graph_def)
	_write_saved_model(saved_model_path, trained_checkpoint_prefix,
	placeholder_tensor, outputs)


	def export_inference_graph(input_type,
	pipeline_config,
	trained_checkpoint_prefix,
	output_directory,
	input_shape=None,
	optimize_graph=True,
	output_collection_name='inference_op',
	additional_output_tensor_names=None):
	"""Exports inference graph for the model specified in the pipeline config.

	Args:
	input_type: Type of input for the graph. Can be one of [`image_tensor`,
	`tf_example`].
	pipeline_config: pipeline_pb2.TrainAndEvalPipelineConfig proto.
	trained_checkpoint_prefix: Path to the trained checkpoint file.
	output_directory: Path to write outputs.
	input_shape: Sets a fixed shape for an `image_tensor` input. If not
	specified, will default to [None, None, None, 3].
	optimize_graph: Whether to optimize graph using Grappler.
	output_collection_name: Name of collection to add output tensors to.
	If None, does not add output tensors to a collection.
	additional_output_tensor_names: list of additional output
	tensors to include in the frozen graph.
	"""
	detection_model = model_builder.build(pipeline_config.model,
	is_training=False)
	_export_inference_graph(input_type, detection_model,
	pipeline_config.eval_config.use_moving_averages,
	trained_checkpoint_prefix,
	output_directory, additional_output_tensor_names,
	input_shape, optimize_graph, output_collection_name)