def scalar(name, tensor, collections=None, family=None):
  """Outputs a `Summary` protocol buffer containing a single scalar value.

  The generated Summary has a Tensor.proto containing the input Tensor.

  Args:
    name: A name for the generated node. Will also serve as the series name in
      TensorBoard.
    tensor: A real numeric Tensor containing a single value.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. Which contains a `Summary` protobuf.

  Raises:
    ValueError: If tensor has the wrong shape or type.
  """
  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  with _summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = _gen_logging_ops.scalar_summary(tags=tag, values=tensor, name=scope)
    _summary_op_util.collect(val, collections, [_ops.GraphKeys.SUMMARIES])
  return val

def merge(inputs, collections=None, name=None):
  # pylint: disable=line-too-long
  """Merges summaries.

  This op creates a
  [`Summary`](https://www.tensorflow.org/code/tensorflow/core/framework/summary.proto)
  protocol buffer that contains the union of all the values in the input
  summaries.

  When the Op is run, it reports an `InvalidArgument` error if multiple values
  in the summaries to merge use the same tag.

  Args:
    inputs: A list of `string` `Tensor` objects containing serialized `Summary`
      protocol buffers.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[]`.
    name: A name for the operation (optional).

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer resulting from the merging.
  """
  # pylint: enable=line-too-long
  name = _summary_op_util.clean_tag(name)
  with _ops.name_scope(name, 'Merge', inputs):
    # pylint: disable=protected-access
    val = _gen_logging_ops._merge_summary(inputs=inputs, name=name)
    _summary_op_util.collect(val, collections, [])
  return val

def _tensor_summary_v2(  # pylint: disable=invalid-name
    name,
    tensor,
    summary_description=None,
    collections=None,
    summary_metadata=None,
    family=None):
  # pylint: disable=line-too-long
  """Outputs a `Summary` protocol buffer with a serialized tensor.proto.

  NOTE(chizeng): This method is temporary. It should never make it into
  TensorFlow 1.3, and nothing should depend on it. This method should be deleted
  before August 2017 (ideally, earlier). This method exists to unblock the
  TensorBoard plugin refactoring effort. We will later modify the tensor_summary
  method to directly make use of the TensorSummaryV2 op. There must be a 3-week
  difference between adding a new op (C++) and changing a python interface to
  use it.

  The generated
  [`Summary`](https://www.tensorflow.org/code/tensorflow/core/framework/summary.proto)
  has one summary value containing the input tensor.

  Args:
    name: A name for the generated node. Will also serve as the series name in
      TensorBoard.
    tensor: A tensor of any type and shape to serialize.
    summary_description: This is currently un-used but must be kept for
      backwards compatibility.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.
    summary_metadata: Optional SummaryMetadata proto (which describes which
      plugins may use the summary value).
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  # pylint: enable=line-too-long

  # The summary description is unused now.
  del summary_description

  serialized_summary_metadata = ""
  if summary_metadata:
    serialized_summary_metadata = summary_metadata.SerializeToString()

  with summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = gen_logging_ops._tensor_summary_v2(
        tensor=tensor,
        tag=tag,
        description="",
        name=scope,
        serialized_summary_metadata=serialized_summary_metadata)
    summary_op_util.collect(val, collections, [ops.GraphKeys.SUMMARIES])
  return val

def image(name, tensor, max_outputs=3, collections=None, family=None):
  """Outputs a `Summary` protocol buffer with images.

  The summary has up to `max_outputs` summary values containing images. The
  images are built from `tensor` which must be 4-D with shape `[batch_size,
  height, width, channels]` and where `channels` can be:

  *  1: `tensor` is interpreted as Grayscale.
  *  3: `tensor` is interpreted as RGB.
  *  4: `tensor` is interpreted as RGBA.

  The images have the same number of channels as the input tensor. For float
  input, the values are normalized one image at a time to fit in the range
  `[0, 255]`.  `uint8` values are unchanged.  The op uses two different
  normalization algorithms:

  *  If the input values are all positive, they are rescaled so the largest one
     is 255.

  *  If any input value is negative, the values are shifted so input value 0.0
     is at 127.  They are then rescaled so that either the smallest value is 0,
     or the largest one is 255.

  The `tag` in the outputted Summary.Value protobufs is generated based on the
  name, with a suffix depending on the max_outputs setting:

  *  If `max_outputs` is 1, the summary value tag is '*name*/image'.
  *  If `max_outputs` is greater than 1, the summary value tags are
     generated sequentially as '*name*/image/0', '*name*/image/1', etc.

  Args:
    name: A name for the generated node. Will also serve as a series name in
      TensorBoard.
    tensor: A 4-D `uint8` or `float32` `Tensor` of shape `[batch_size, height,
      width, channels]` where `channels` is 1, 3, or 4.
    max_outputs: Max number of batch elements to generate images for.
    collections: Optional list of ops.GraphKeys.  The collections to add the
      summary to.  Defaults to [_ops.GraphKeys.SUMMARIES]
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  with _summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = _gen_logging_ops.image_summary(
        tag=tag, tensor=tensor, max_images=max_outputs, name=scope)
    _summary_op_util.collect(val, collections, [_ops.GraphKeys.SUMMARIES])
  return val

def tensor_summary(name,
                   tensor,
                   summary_description=None,
                   collections=None,
                   summary_metadata=None,
                   family=None,
                   display_name=None):
  """Outputs a `Summary` protocol buffer with a serialized tensor.proto.

  Args:
    name: A name for the generated node. If display_name is not set, it will
      also serve as the tag name in TensorBoard. (In that case, the tag
      name will inherit tf name scopes.)
    tensor: A tensor of any type and shape to serialize.
    summary_description: A long description of the summary sequence. Markdown
      is supported.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.
    summary_metadata: Optional SummaryMetadata proto (which describes which
      plugins may use the summary value).
    family: Optional; if provided, used as the prefix of the summary tag,
      which controls the name used for display on TensorBoard when
      display_name is not set.
    display_name: A string used to name this data in TensorBoard. If this is
      not set, then the node name will be used instead.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """

  if summary_metadata is None:
    summary_metadata = _SummaryMetadata()

  if summary_description is not None:
    summary_metadata.summary_description = summary_description

  if display_name is not None:
    summary_metadata.display_name = display_name

  serialized_summary_metadata = summary_metadata.SerializeToString()

  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  with _summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = _gen_logging_ops.tensor_summary_v2(
        tensor=tensor,
        tag=tag,
        name=scope,
        serialized_summary_metadata=serialized_summary_metadata)
    _summary_op_util.collect(val, collections, [_ops.GraphKeys.SUMMARIES])
  return val

def audio(name, tensor, sample_rate, max_outputs=3, collections=None,
          family=None):
  # pylint: disable=line-too-long
  """Outputs a `Summary` protocol buffer with audio.

  The summary has up to `max_outputs` summary values containing audio. The
  audio is built from `tensor` which must be 3-D with shape `[batch_size,
  frames, channels]` or 2-D with shape `[batch_size, frames]`. The values are
  assumed to be in the range of `[-1.0, 1.0]` with a sample rate of
  `sample_rate`.

  The `tag` in the outputted Summary.Value protobufs is generated based on the
  name, with a suffix depending on the max_outputs setting:

  *  If `max_outputs` is 1, the summary value tag is '*name*/audio'.
  *  If `max_outputs` is greater than 1, the summary value tags are
     generated sequentially as '*name*/audio/0', '*name*/audio/1', etc

  Args:
    name: A name for the generated node. Will also serve as a series name in
      TensorBoard.
    tensor: A 3-D `float32` `Tensor` of shape `[batch_size, frames, channels]`
      or a 2-D `float32` `Tensor` of shape `[batch_size, frames]`.
    sample_rate: A Scalar `float32` `Tensor` indicating the sample rate of the
      signal in hertz.
    max_outputs: Max number of batch elements to generate audio for.
    collections: Optional list of ops.GraphKeys.  The collections to add the
      summary to.  Defaults to [_ops.GraphKeys.SUMMARIES]
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  with _summary_op_util.summary_scope(
      name, family=family, values=[tensor]) as (tag, scope):
    sample_rate = _ops.convert_to_tensor(
        sample_rate, dtype=_dtypes.float32, name='sample_rate')
    val = _gen_logging_ops.audio_summary_v2(
        tag=tag, tensor=tensor, max_outputs=max_outputs,
        sample_rate=sample_rate, name=scope)
    _summary_op_util.collect(val, collections, [_ops.GraphKeys.SUMMARIES])
  return val

def merge(inputs, collections=None, name=None):
  # pylint: disable=line-too-long
  """Merges summaries.

  This op creates a
  [`Summary`](https://www.tensorflow.org/code/tensorflow/core/framework/summary.proto)
  protocol buffer that contains the union of all the values in the input
  summaries.

  When the Op is run, it reports an `InvalidArgument` error if multiple values
  in the summaries to merge use the same tag.

  Args:
    inputs: A list of `string` `Tensor` objects containing serialized `Summary`
      protocol buffers.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[]`.
    name: A name for the operation (optional).

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer resulting from the merging.

  Raises:
    RuntimeError: If called with eager mode enabled.

  @compatibility(eager)
  Not compatible with eager execution. To write TensorBoard
  summaries under eager execution, use `tf.contrib.summary` instead.
  @end_compatibility
  """
  # pylint: enable=line-too-long
  if _context.executing_eagerly():
    raise RuntimeError(
        'Merging tf.summary.* ops is not compatible with eager execution. '
        'Use tf.contrib.summary instead.')
  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  name = _summary_op_util.clean_tag(name)
  with _ops.name_scope(name, 'Merge', inputs):
    val = _gen_logging_ops.merge_summary(inputs=inputs, name=name)
    _summary_op_util.collect(val, collections, [])
  return val

def tensor_summary(
    name,
    tensor,
    summary_description=None,
    collections=None,
    summary_metadata=None,
    family=None):
  """Outputs a `Summary` protocol buffer with a serialized tensor.proto.

  Args:
    name: A name for the generated node. Will also serve as the series name in
      TensorBoard.
    tensor: A tensor of any type and shape to serialize.
    summary_description: This is currently un-used but must be kept for
      backwards compatibility.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.
    summary_metadata: Optional SummaryMetadata proto (which describes which
      plugins may use the summary value).
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  # The summary description is unused now.
  del summary_description

  serialized_summary_metadata = ""
  if summary_metadata:
    serialized_summary_metadata = summary_metadata.SerializeToString()

  with summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = gen_logging_ops._tensor_summary_v2(
        tensor=tensor,
        tag=tag,
        name=scope,
        serialized_summary_metadata=serialized_summary_metadata)
    summary_op_util.collect(val, collections, [ops.GraphKeys.SUMMARIES])
  return val

def gif_summary(name, tensor, max_outputs=3, fps=10, collections=None,
                family=None):
  """Outputs a `Summary` protocol buffer with gif animations.

  Args:
    name: Name of the summary.
    tensor: A 5-D `uint8` `Tensor` of shape `[batch_size, time, height, width,
      channels]` where `channels` is 1 or 3.
    max_outputs: Max number of batch elements to generate gifs for.
    fps: frames per second of the animation
    collections: Optional list of tf.GraphKeys.  The collections to add the
      summary to.  Defaults to [tf.GraphKeys.SUMMARIES]
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.

  Raises:
    ValueError: if the given tensor has the wrong shape.
  """
  tensor = tf.convert_to_tensor(tensor)
  if len(tensor.get_shape()) != 5:
    raise ValueError("Assuming videos given as tensors in the format "
                     "[batch, time, height, width, channels] but got one "
                     "of shape: %s" % str(tensor.get_shape()))
  tensor = tf.cast(tensor, tf.uint8)
  if summary_op_util.skip_summary():
    return tf.constant("")
  with summary_op_util.summary_scope(
      name, family, values=[tensor]) as (tag, scope):
    val = tf.py_func(
        py_gif_summary,
        [tag, tensor, max_outputs, fps],
        tf.string,
        stateful=False,
        name=scope)
    summary_op_util.collect(val, collections, [tf.GraphKeys.SUMMARIES])
  return val

def histogram(name, values, collections=None, family=None):
  # pylint: disable=line-too-long
  """Outputs a `Summary` protocol buffer with a histogram.

  Adding a histogram summary makes it possible to visualize your data's
  distribution in TensorBoard. You can see a detailed explanation of the
  TensorBoard histogram dashboard
  [here](https://www.tensorflow.org/get_started/tensorboard_histograms).

  The generated
  [`Summary`](https://www.tensorflow.org/code/tensorflow/core/framework/summary.proto)
  has one summary value containing a histogram for `values`.

  This op reports an `InvalidArgument` error if any value is not finite.

  Args:
    name: A name for the generated node. Will also serve as a series name in
      TensorBoard.
    values: A real numeric `Tensor`. Any shape. Values to use to
      build the histogram.
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.
    family: Optional; if provided, used as the prefix of the summary tag name,
      which controls the tab name used for display on Tensorboard.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  if _summary_op_util.skip_summary():
    return _constant_op.constant('')
  with _summary_op_util.summary_scope(
      name, family, values=[values],
      default_name='HistogramSummary') as (tag, scope):
    val = _gen_logging_ops.histogram_summary(
        tag=tag, values=values, name=scope)
    _summary_op_util.collect(val, collections, [_ops.GraphKeys.SUMMARIES])
  return val

def tensor_summary(  # pylint: disable=invalid-name
    name,
    tensor,
    summary_description=None,
    collections=None):
  # pylint: disable=line-too-long
  """Outputs a `Summary` protocol buffer with a serialized tensor.proto.

  The generated
  [`Summary`](https://www.tensorflow.org/code/tensorflow/core/framework/summary.proto)
  has one summary value containing the input tensor.

  Args:
    name: A name for the generated node. Will also serve as the series name in
      TensorBoard.
    tensor: A tensor of any type and shape to serialize.
    summary_description: Optional summary_pb2.SummaryDescription()
    collections: Optional list of graph collections keys. The new summary op is
      added to these collections. Defaults to `[GraphKeys.SUMMARIES]`.

  Returns:
    A scalar `Tensor` of type `string`. The serialized `Summary` protocol
    buffer.
  """
  # pylint: enable=line-too-long

  if summary_description is None:
    summary_description = summary_pb2.SummaryDescription()

  description = json_format.MessageToJson(summary_description)
  with ops.name_scope(name, None, [tensor]) as scope:
    val = gen_logging_ops._tensor_summary(
        tensor=tensor,
        description=description,
        name=scope)
    summary_op_util.collect(val, collections, [ops.GraphKeys.SUMMARIES])
  return val