# 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.
# ==============================================================================
r"""Creates and runs `Experiment` for object detection model.
This uses the TF.learn framework to define and run an object detection model
wrapped in an `Estimator`.
Note that this module is only compatible with SSD Meta architecture at the
moment.
"""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import functools
import os
import tensorflow as tf
from google.protobuf import text_format
from tensorflow.contrib.learn.python.learn import learn_runner
from tensorflow.contrib.tpu.python.tpu import tpu_optimizer
from tensorflow.python.lib.io import file_io
from object_detection import eval_util
from object_detection import inputs
from object_detection import model_hparams
from object_detection.builders import model_builder
from object_detection.builders import optimizer_builder
from object_detection.core import standard_fields as fields
from object_detection.utils import config_util
from object_detection.utils import label_map_util
from object_detection.utils import shape_utils
from object_detection.utils import variables_helper
from object_detection.utils import visualization_utils as vis_utils
tf.flags.DEFINE_string('model_dir', None, 'Path to output model directory '
'where event and checkpoint files will be written.')
tf.flags.DEFINE_string('pipeline_config_path', None, 'Path to pipeline config '
'file.')
tf.flags.DEFINE_integer('num_train_steps', 500000, 'Number of train steps.')
tf.flags.DEFINE_integer('num_eval_steps', 10000, 'Number of train steps.')
FLAGS = tf.flags.FLAGS
# A map of names to methods that help build the model.
MODEL_BUILD_UTIL_MAP = {
'get_configs_from_pipeline_file':
config_util.get_configs_from_pipeline_file,
'create_pipeline_proto_from_configs':
config_util.create_pipeline_proto_from_configs,
'merge_external_params_with_configs':
config_util.merge_external_params_with_configs,
'create_train_input_fn': inputs.create_train_input_fn,
'create_eval_input_fn': inputs.create_eval_input_fn,
'create_predict_input_fn': inputs.create_predict_input_fn,
}
def _get_groundtruth_data(detection_model, class_agnostic):
"""Extracts groundtruth data from detection_model.
Args:
detection_model: A `DetectionModel` object.
class_agnostic: Whether the detections are class_agnostic.
Returns:
A tuple of:
groundtruth: Dictionary with the following fields:
'groundtruth_boxes': [num_boxes, 4] float32 tensor of boxes, in
normalized coordinates.
'groundtruth_classes': [num_boxes] int64 tensor of 1-indexed classes.
'groundtruth_masks': 3D float32 tensor of instance masks (if provided in
groundtruth)
class_agnostic: Boolean indicating whether detections are class agnostic.
"""
input_data_fields = fields.InputDataFields()
groundtruth_boxes = detection_model.groundtruth_lists(
fields.BoxListFields.boxes)[0]
# For class-agnostic models, groundtruth one-hot encodings collapse to all
# ones.
if class_agnostic:
groundtruth_boxes_shape = tf.shape(groundtruth_boxes)
groundtruth_classes_one_hot = tf.ones([groundtruth_boxes_shape[0], 1])
else:
groundtruth_classes_one_hot = detection_model.groundtruth_lists(
fields.BoxListFields.classes)[0]
label_id_offset = 1 # Applying label id offset (b/63711816)
groundtruth_classes = (
tf.argmax(groundtruth_classes_one_hot, axis=1) + label_id_offset)
groundtruth = {
input_data_fields.groundtruth_boxes: groundtruth_boxes,
input_data_fields.groundtruth_classes: groundtruth_classes
}
if detection_model.groundtruth_has_field(fields.BoxListFields.masks):
groundtruth[input_data_fields.groundtruth_instance_masks] = (
detection_model.groundtruth_lists(fields.BoxListFields.masks)[0])
return groundtruth
def unstack_batch(tensor_dict, unpad_groundtruth_tensors=True):
"""Unstacks all tensors in `tensor_dict` along 0th dimension.
Unstacks tensor from the tensor dict along 0th dimension and returns a
tensor_dict containing values that are lists of unstacked tensors.
Tensors in the `tensor_dict` are expected to be of one of the three shapes:
1. [batch_size]
2. [batch_size, height, width, channels]
3. [batch_size, num_boxes, d1, d2, ... dn]
When unpad_groundtruth_tensors is set to true, unstacked tensors of form 3
above are sliced along the `num_boxes` dimension using the value in tensor
field.InputDataFields.num_groundtruth_boxes.
Note that this function has a static list of input data fields and has to be
kept in sync with the InputDataFields defined in core/standard_fields.py
Args:
tensor_dict: A dictionary of batched groundtruth tensors.
unpad_groundtruth_tensors: Whether to remove padding along `num_boxes`
dimension of the groundtruth tensors.
Returns:
A dictionary where the keys are from fields.InputDataFields and values are
a list of unstacked (optionally unpadded) tensors.
Raises:
ValueError: If unpad_tensors is True and `tensor_dict` does not contain
`num_groundtruth_boxes` tensor.
"""
unbatched_tensor_dict = {key: tf.unstack(tensor)
for key, tensor in tensor_dict.items()}
if unpad_groundtruth_tensors:
if (fields.InputDataFields.num_groundtruth_boxes not in
unbatched_tensor_dict):
raise ValueError('`num_groundtruth_boxes` not found in tensor_dict. '
'Keys available: {}'.format(
unbatched_tensor_dict.keys()))
unbatched_unpadded_tensor_dict = {}
unpad_keys = set([
# List of input data fields that are padded along the num_boxes
# dimension. This list has to be kept in sync with InputDataFields in
# standard_fields.py.
fields.InputDataFields.groundtruth_instance_masks,
fields.InputDataFields.groundtruth_classes,
fields.InputDataFields.groundtruth_boxes,
fields.InputDataFields.groundtruth_keypoints,
fields.InputDataFields.groundtruth_group_of,
fields.InputDataFields.groundtruth_difficult,
fields.InputDataFields.groundtruth_is_crowd,
fields.InputDataFields.groundtruth_area,
fields.InputDataFields.groundtruth_weights
]).intersection(set(unbatched_tensor_dict.keys()))
for key in unpad_keys:
unpadded_tensor_list = []
for num_gt, padded_tensor in zip(
unbatched_tensor_dict[fields.InputDataFields.num_groundtruth_boxes],
unbatched_tensor_dict[key]):
tensor_shape = shape_utils.combined_static_and_dynamic_shape(
padded_tensor)
slice_begin = tf.zeros([len(tensor_shape)], dtype=tf.int32)
slice_size = tf.stack(
[num_gt] + [-1 if dim is None else dim for dim in tensor_shape[1:]])
unpadded_tensor = tf.slice(padded_tensor, slice_begin, slice_size)
unpadded_tensor_list.append(unpadded_tensor)
unbatched_unpadded_tensor_dict[key] = unpadded_tensor_list
unbatched_tensor_dict.update(unbatched_unpadded_tensor_dict)
return unbatched_tensor_dict
def create_model_fn(detection_model_fn, configs, hparams, use_tpu=False):
"""Creates a model function for `Estimator`.
Args:
detection_model_fn: Function that returns a `DetectionModel` instance.
configs: Dictionary of pipeline config objects.
hparams: `HParams` object.
use_tpu: Boolean indicating whether model should be constructed for
use on TPU.
Returns:
`model_fn` for `Estimator`.
"""
train_config = configs['train_config']
eval_input_config = configs['eval_input_config']
eval_config = configs['eval_config']
def model_fn(features, labels, mode, params=None):
"""Constructs the object detection model.
Args:
features: Dictionary of feature tensors, returned from `input_fn`.
labels: Dictionary of groundtruth tensors if mode is TRAIN or EVAL,
otherwise None.
mode: Mode key from tf.estimator.ModeKeys.
params: Parameter dictionary passed from the estimator.
Returns:
An `EstimatorSpec` that encapsulates the model and its serving
configurations.
"""
params = params or {}
total_loss, train_op, detections, export_outputs = None, None, None, None
is_training = mode == tf.estimator.ModeKeys.TRAIN
detection_model = detection_model_fn(is_training=is_training,
add_summaries=(not use_tpu))
scaffold_fn = None
if mode == tf.estimator.ModeKeys.TRAIN:
labels = unstack_batch(
labels,
unpad_groundtruth_tensors=train_config.unpad_groundtruth_tensors)
elif mode == tf.estimator.ModeKeys.EVAL:
labels = unstack_batch(labels, unpad_groundtruth_tensors=False)
if mode in (tf.estimator.ModeKeys.TRAIN, tf.estimator.ModeKeys.EVAL):
gt_boxes_list = labels[fields.InputDataFields.groundtruth_boxes]
gt_classes_list = labels[fields.InputDataFields.groundtruth_classes]
gt_masks_list = None
if fields.InputDataFields.groundtruth_instance_masks in labels:
gt_masks_list = labels[
fields.InputDataFields.groundtruth_instance_masks]
gt_keypoints_list = None
if fields.InputDataFields.groundtruth_keypoints in labels:
gt_keypoints_list = labels[fields.InputDataFields.groundtruth_keypoints]
detection_model.provide_groundtruth(
groundtruth_boxes_list=gt_boxes_list,
groundtruth_classes_list=gt_classes_list,
groundtruth_masks_list=gt_masks_list,
groundtruth_keypoints_list=gt_keypoints_list)
preprocessed_images = features[fields.InputDataFields.image]
prediction_dict = detection_model.predict(
preprocessed_images, features[fields.InputDataFields.true_image_shape])
detections = detection_model.postprocess(
prediction_dict, features[fields.InputDataFields.true_image_shape])
if mode == tf.estimator.ModeKeys.TRAIN:
if not train_config.fine_tune_checkpoint_type:
# train_config.from_detection_checkpoint field is deprecated. For
# backward compatibility, sets finetune_checkpoint_type based on
# from_detection_checkpoint.
if train_config.from_detection_checkpoint:
train_config.fine_tune_checkpoint_type = 'detection'
else:
train_config.fine_tune_checkpoint_type = 'classification'
if train_config.fine_tune_checkpoint and hparams.load_pretrained:
if not train_config.fine_tune_checkpoint_type:
# train_config.from_detection_checkpoint field is deprecated. For
# backward compatibility, set train_config.fine_tune_checkpoint_type
# based on train_config.from_detection_checkpoint.
if train_config.from_detection_checkpoint:
train_config.fine_tune_checkpoint_type = 'detection'
else:
train_config.fine_tune_checkpoint_type = 'classification'
asg_map = detection_model.restore_map(
fine_tune_checkpoint_type=train_config.fine_tune_checkpoint_type,
load_all_detection_checkpoint_vars=(
train_config.load_all_detection_checkpoint_vars))
available_var_map = (
variables_helper.get_variables_available_in_checkpoint(
asg_map, train_config.fine_tune_checkpoint,
include_global_step=False))
if use_tpu:
def tpu_scaffold():
tf.train.init_from_checkpoint(train_config.fine_tune_checkpoint,
available_var_map)
return tf.train.Scaffold()
scaffold_fn = tpu_scaffold
else:
tf.train.init_from_checkpoint(train_config.fine_tune_checkpoint,
available_var_map)
if mode in (tf.estimator.ModeKeys.TRAIN, tf.estimator.ModeKeys.EVAL):
losses_dict = detection_model.loss(
prediction_dict, features[fields.InputDataFields.true_image_shape])
losses = [loss_tensor for loss_tensor in losses_dict.itervalues()]
if train_config.add_regularization_loss:
regularization_losses = tf.get_collection(
tf.GraphKeys.REGULARIZATION_LOSSES)
if regularization_losses:
regularization_loss = tf.add_n(regularization_losses,
name='regularization_loss')
losses.append(regularization_loss)
if not use_tpu:
tf.summary.scalar('regularization_loss', regularization_loss)
total_loss = tf.add_n(losses, name='total_loss')
if mode == tf.estimator.ModeKeys.TRAIN:
global_step = tf.train.get_or_create_global_step()
training_optimizer, optimizer_summary_vars = optimizer_builder.build(
train_config.optimizer)
if use_tpu:
training_optimizer = tpu_optimizer.CrossShardOptimizer(
training_optimizer)
# Optionally freeze some layers by setting their gradients to be zero.
trainable_variables = None
if train_config.freeze_variables:
trainable_variables = tf.contrib.framework.filter_variables(
tf.trainable_variables(),
exclude_patterns=train_config.freeze_variables)
clip_gradients_value = None
if train_config.gradient_clipping_by_norm > 0:
clip_gradients_value = train_config.gradient_clipping_by_norm
if not use_tpu:
for var in optimizer_summary_vars:
tf.summary.scalar(var.op.name, var)
summaries = [] if use_tpu else None
train_op = tf.contrib.layers.optimize_loss(
loss=total_loss,
global_step=global_step,
learning_rate=None,
clip_gradients=clip_gradients_value,
optimizer=training_optimizer,
variables=trainable_variables,
summaries=summaries,
name='') # Preventing scope prefix on all variables.
if mode == tf.estimator.ModeKeys.PREDICT:
export_outputs = {
tf.saved_model.signature_constants.PREDICT_METHOD_NAME:
tf.estimator.export.PredictOutput(detections)
}
eval_metric_ops = None
if mode == tf.estimator.ModeKeys.EVAL:
# Detection summaries during eval.
class_agnostic = (fields.DetectionResultFields.detection_classes
not in detections)
groundtruth = _get_groundtruth_data(detection_model, class_agnostic)
use_original_images = fields.InputDataFields.original_image in features
eval_images = (
features[fields.InputDataFields.original_image] if use_original_images
else features[fields.InputDataFields.image])
eval_dict = eval_util.result_dict_for_single_example(
eval_images[0:1],
features[inputs.HASH_KEY][0],
detections,
groundtruth,
class_agnostic=class_agnostic,
scale_to_absolute=False)
if class_agnostic:
category_index = label_map_util.create_class_agnostic_category_index()
else:
category_index = label_map_util.create_category_index_from_labelmap(
eval_input_config.label_map_path)
if not use_tpu and use_original_images:
detection_and_groundtruth = (
vis_utils.draw_side_by_side_evaluation_image(
eval_dict, category_index, max_boxes_to_draw=20,
min_score_thresh=0.2))
tf.summary.image('Detections_Left_Groundtruth_Right',
detection_and_groundtruth)
# Eval metrics on a single image.
eval_metrics = eval_config.metrics_set
if not eval_metrics:
eval_metrics = ['coco_detection_metrics']
eval_metric_ops = eval_util.get_eval_metric_ops_for_evaluators(
eval_metrics, category_index.values(), eval_dict,
include_metrics_per_category=False)
if use_tpu:
return tf.contrib.tpu.TPUEstimatorSpec(
mode=mode,
scaffold_fn=scaffold_fn,
predictions=detections,
loss=total_loss,
train_op=train_op,
eval_metrics=eval_metric_ops,
export_outputs=export_outputs)
else:
return tf.estimator.EstimatorSpec(
mode=mode,
predictions=detections,
loss=total_loss,
train_op=train_op,
eval_metric_ops=eval_metric_ops,
export_outputs=export_outputs)
return model_fn
def build_experiment_fn(train_steps, eval_steps):
"""Returns a function that creates an `Experiment`."""
def build_experiment(run_config, hparams):
"""Builds an `Experiment` from configuration and hyperparameters.
Args:
run_config: A `RunConfig`.
hparams: A `HParams`.
Returns:
An `Experiment` object.
"""
return populate_experiment(run_config, hparams, FLAGS.pipeline_config_path,
train_steps, eval_steps)
return build_experiment
def populate_experiment(run_config,
hparams,
pipeline_config_path,
train_steps=None,
eval_steps=None,
model_fn_creator=create_model_fn,
**kwargs):
"""Populates an `Experiment` object.
Args:
run_config: A `RunConfig`.
hparams: A `HParams`.
pipeline_config_path: A path to a pipeline config file.
train_steps: Number of training steps. If None, the number of training steps
is set from the `TrainConfig` proto.
eval_steps: Number of evaluation steps per evaluation cycle. If None, the
number of evaluation steps is set from the `EvalConfig` proto.
model_fn_creator: A function that creates a `model_fn` for `Estimator`.
Follows the signature:
* Args:
* `detection_model_fn`: Function that returns `DetectionModel` instance.
* `configs`: Dictionary of pipeline config objects.
* `hparams`: `HParams` object.
* Returns:
`model_fn` for `Estimator`.
**kwargs: Additional keyword arguments for configuration override.
Returns:
An `Experiment` that defines all aspects of training, evaluation, and
export.
"""
get_configs_from_pipeline_file = MODEL_BUILD_UTIL_MAP[
'get_configs_from_pipeline_file']
create_pipeline_proto_from_configs = MODEL_BUILD_UTIL_MAP[
'create_pipeline_proto_from_configs']
merge_external_params_with_configs = MODEL_BUILD_UTIL_MAP[
'merge_external_params_with_configs']
create_train_input_fn = MODEL_BUILD_UTIL_MAP['create_train_input_fn']
create_eval_input_fn = MODEL_BUILD_UTIL_MAP['create_eval_input_fn']
create_predict_input_fn = MODEL_BUILD_UTIL_MAP['create_predict_input_fn']
configs = get_configs_from_pipeline_file(pipeline_config_path)
configs = merge_external_params_with_configs(
configs,
hparams,
train_steps=train_steps,
eval_steps=eval_steps,
**kwargs)
model_config = configs['model']
train_config = configs['train_config']
train_input_config = configs['train_input_config']
eval_config = configs['eval_config']
eval_input_config = configs['eval_input_config']
if train_steps is None and train_config.num_steps:
train_steps = train_config.num_steps
if eval_steps is None and eval_config.num_examples:
eval_steps = eval_config.num_examples
detection_model_fn = functools.partial(
model_builder.build, model_config=model_config)
# Create the input functions for TRAIN/EVAL.
train_input_fn = create_train_input_fn(
train_config=train_config,
train_input_config=train_input_config,
model_config=model_config)
eval_input_fn = create_eval_input_fn(
eval_config=eval_config,
eval_input_config=eval_input_config,
model_config=model_config)
export_strategies = [
tf.contrib.learn.utils.saved_model_export_utils.make_export_strategy(
serving_input_fn=create_predict_input_fn(
model_config=model_config))
]
estimator = tf.estimator.Estimator(
model_fn=model_fn_creator(detection_model_fn, configs, hparams),
config=run_config)
if run_config.is_chief:
# Store the final pipeline config for traceability.
pipeline_config_final = create_pipeline_proto_from_configs(
configs)
if not file_io.file_exists(estimator.model_dir):
file_io.recursive_create_dir(estimator.model_dir)
pipeline_config_final_path = os.path.join(estimator.model_dir,
'pipeline.config')
config_text = text_format.MessageToString(pipeline_config_final)
with tf.gfile.Open(pipeline_config_final_path, 'wb') as f:
tf.logging.info('Writing as-run pipeline config file to %s',
pipeline_config_final_path)
f.write(config_text)
return tf.contrib.learn.Experiment(
estimator=estimator,
train_input_fn=train_input_fn,
eval_input_fn=eval_input_fn,
train_steps=train_steps,
eval_steps=eval_steps,
export_strategies=export_strategies,
eval_delay_secs=120,)
def main(unused_argv):
tf.flags.mark_flag_as_required('model_dir')
tf.flags.mark_flag_as_required('pipeline_config_path')
config = tf.contrib.learn.RunConfig(model_dir=FLAGS.model_dir)
learn_runner.run(
experiment_fn=build_experiment_fn(FLAGS.num_train_steps,
FLAGS.num_eval_steps),
run_config=config,
hparams=model_hparams.create_hparams())
if __name__ == '__main__':
tf.app.run()
