Exemplo n.º 1
0
def setup_model(config):
    """Build and compile model."""
    model = train_lib.EfficientDetNetTrain(config=config)
    model.build((None, *config.image_size, 3))
    model.compile(
        optimizer=train_lib.get_optimizer(config.as_dict()),
        loss={
            train_lib.BoxLoss.__name__:
            train_lib.BoxLoss(config.delta,
                              reduction=tf.keras.losses.Reduction.NONE),
            train_lib.BoxIouLoss.__name__:
            train_lib.BoxIouLoss(config.iou_loss_type,
                                 config.min_level,
                                 config.max_level,
                                 config.num_scales,
                                 config.aspect_ratios,
                                 config.anchor_scale,
                                 config.image_size,
                                 reduction=tf.keras.losses.Reduction.NONE),
            train_lib.FocalLoss.__name__:
            train_lib.FocalLoss(config.alpha,
                                config.gamma,
                                label_smoothing=config.label_smoothing,
                                reduction=tf.keras.losses.Reduction.NONE),
            tf.keras.losses.SparseCategoricalCrossentropy.__name__:
            tf.keras.losses.SparseCategoricalCrossentropy(
                from_logits=True, reduction=tf.keras.losses.Reduction.NONE)
        })
    return model
Exemplo n.º 2
0
    def _build_model(self, grad_checkpoint=False):
        tf.random.set_seed(1111)
        config = hparams_config.get_detection_config('efficientdet-d0')
        config.heads = ['object_detection', 'segmentation']
        config.batch_size = 1
        config.num_examples_per_epoch = 1
        config.model_dir = tempfile.mkdtemp()
        config.steps_per_epoch = 1
        config.mixed_precision = True
        config.grad_checkpoint = grad_checkpoint
        x = tf.ones((1, 512, 512, 3))
        labels = {
            'box_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 36))
            for i in range(3, 8)
        }
        labels.update({
            'cls_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 9),
                                          dtype=tf.int32)
            for i in range(3, 8)
        })
        labels.update({'image_masks': tf.ones((1, 128, 128, 1))})
        labels.update({'mean_num_positives': tf.constant([10.0])})

        params = config.as_dict()
        params['num_shards'] = 1
        params['steps_per_execution'] = 100
        params['model_dir'] = tempfile.mkdtemp()
        params['profile'] = False
        config.override(params, allow_new_keys=True)
        model = train_lib.EfficientDetNetTrain(config=config)
        model.build((1, 512, 512, 3))
        model.compile(
            optimizer=train_lib.get_optimizer(params),
            loss={
                train_lib.BoxLoss.__name__:
                train_lib.BoxLoss(params['delta'],
                                  reduction=tf.keras.losses.Reduction.NONE),
                train_lib.BoxIouLoss.__name__:
                train_lib.BoxIouLoss(params['iou_loss_type'],
                                     params['min_level'],
                                     params['max_level'],
                                     params['num_scales'],
                                     params['aspect_ratios'],
                                     params['anchor_scale'],
                                     params['image_size'],
                                     reduction=tf.keras.losses.Reduction.NONE),
                train_lib.FocalLoss.__name__:
                train_lib.FocalLoss(params['alpha'],
                                    params['gamma'],
                                    label_smoothing=params['label_smoothing'],
                                    reduction=tf.keras.losses.Reduction.NONE),
                tf.keras.losses.SparseCategoricalCrossentropy.__name__:
                tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True)
            })
        return params, x, labels, model
Exemplo n.º 3
0
 def test_display_callback(self):
   config = hparams_config.get_detection_config('efficientdet-d0')
   config.batch_size = 1
   config.num_examples_per_epoch = 1
   config.model_dir = tempfile.mkdtemp()
   sample_image = tf.ones([416, 416, 3])
   display_callback = train_lib.DisplayCallback(sample_image)
   model = train_lib.EfficientDetNetTrain(config=config)
   model.build((1, 512, 512, 3))
   display_callback.set_model(model)
   display_callback.on_epoch_end(0, {})
Exemplo n.º 4
0
    def test_train(self):
        tf.random.set_seed(1111)
        config = hparams_config.get_detection_config('efficientdet-d0')
        config.batch_size = 1
        config.num_examples_per_epoch = 1
        config.model_dir = tempfile.mkdtemp()
        x = tf.ones((1, 512, 512, 3))
        labels = {
            'box_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 36))
            for i in range(3, 8)
        }
        labels.update({
            'cls_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 9),
                                          dtype=tf.int32)
            for i in range(3, 8)
        })
        labels.update({'mean_num_positives': tf.constant([10.0])})

        params = config.as_dict()
        params['num_shards'] = 1
        model = train_lib.EfficientDetNetTrain(config=config)
        model.build((1, 512, 512, 3))
        model.compile(
            optimizer=train_lib.get_optimizer(params),
            loss={
                'box_loss':
                train_lib.BoxLoss(params['delta'],
                                  reduction=tf.keras.losses.Reduction.NONE),
                'box_iou_loss':
                train_lib.BoxIouLoss(params['iou_loss_type'],
                                     reduction=tf.keras.losses.Reduction.NONE),
                'class_loss':
                train_lib.FocalLoss(params['alpha'],
                                    params['gamma'],
                                    label_smoothing=params['label_smoothing'],
                                    reduction=tf.keras.losses.Reduction.NONE)
            })

        # Test single-batch
        outputs = model.train_on_batch(x, labels, return_dict=True)
        self.assertAllClose(outputs, {'loss': 26278.2539}, rtol=.1, atol=100.)
        outputs = model.test_on_batch(x, labels, return_dict=True)
        self.assertAllClose(outputs, {'loss': 26061.1582}, rtol=.1, atol=100.)

        # Test fit.
        hist = model.fit(x,
                         labels,
                         steps_per_epoch=1,
                         epochs=1,
                         callbacks=train_lib.get_callbacks(params))
        self.assertAllClose(hist.history, {'loss': [26061.1582]},
                            rtol=.1,
                            atol=100.)
Exemplo n.º 5
0
 def test_display_callback(self):
   config = hparams_config.get_detection_config('efficientdet-d0')
   config.batch_size = 1
   config.num_examples_per_epoch = 1
   config.model_dir = tempfile.mkdtemp()
   fake_image = tf.ones([512, 512, 3], dtype=tf.uint8)
   fake_jpeg = tf.image.encode_jpeg(fake_image)
   sample_image = 'ram://fake_image.jpg'
   tf.io.write_file(sample_image, fake_jpeg)
   display_callback = train_lib.DisplayCallback(sample_image, config.model_dir)
   model = train_lib.EfficientDetNetTrain(config=config)
   model.build((1, 512, 512, 3))
   display_callback.set_model(model)
   display_callback.on_epoch_end(0, {})
Exemplo n.º 6
0
 def test_predict(self):
     x = np.random.random((1, 512, 512, 3)).astype(np.float32)
     model = train_lib.EfficientDetNetTrain('efficientdet-d0')
     cls_outputs, box_outputs = model(x)
     self.assertLen(cls_outputs, 5)
     self.assertLen(box_outputs, 5)
Exemplo n.º 7
0
  def test_train(self):
    tf.random.set_seed(1111)
    config = hparams_config.get_detection_config('efficientdet-d0')
    config.batch_size = 1
    config.num_examples_per_epoch = 1
    config.model_dir = tempfile.mkdtemp()
    x = tf.ones((1, 512, 512, 3))
    labels = {
        'box_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 36))
        for i in range(3, 8)
    }
    labels.update({
        'cls_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 9),
                                      dtype=tf.int32) for i in range(3, 8)
    })
    labels.update({'mean_num_positives': tf.constant([10.0])})

    params = config.as_dict()
    params['num_shards'] = 1
    model = train_lib.EfficientDetNetTrain(config=config)
    model.build((1, 512, 512, 3))
    model.compile(
        optimizer=train_lib.get_optimizer(params),
        loss={
            'box_loss':
                train_lib.BoxLoss(
                    params['delta'], reduction=tf.keras.losses.Reduction.NONE),
            'box_iou_loss':
                train_lib.BoxIouLoss(
                    params['iou_loss_type'],
                    reduction=tf.keras.losses.Reduction.NONE),
            'class_loss':
                train_lib.FocalLoss(
                    params['alpha'],
                    params['gamma'],
                    label_smoothing=params['label_smoothing'],
                    reduction=tf.keras.losses.Reduction.NONE)
        })

    # Test single-batch
    outputs = model.train_on_batch(x, labels, return_dict=True)
    expect_results = {'loss': 26278.25,
                      'det_loss': 26277.033203125,
                      'cls_loss': 5060.716796875,
                      'box_loss': 424.3263244628906,
                      'box_iou_loss': 0,
                      'gnorm': 5873.78759765625}
    self.assertAllClose(outputs, expect_results, rtol=.1, atol=100.)
    outputs = model.test_on_batch(x, labels, return_dict=True)
    expect_results = {'loss': 26079.712890625,
                      'det_loss': 26078.49609375,
                      'cls_loss': 5063.3759765625,
                      'box_loss': 420.30242919921875,
                      'box_iou_loss': 0}
    self.assertAllClose(outputs, expect_results, rtol=.1, atol=100.)

    # Test fit.
    hist = model.fit(
        x,
        labels,
        steps_per_epoch=1,
        epochs=1,
        callbacks=train_lib.get_callbacks(params))
    expect_results = {'loss': [26063.099609375],
                      'det_loss': [26061.8828125],
                      'cls_loss': [5058.1337890625],
                      'box_loss': [420.074951171875],
                      'box_iou_loss': [0],
                      'gnorm': [5107.46435546875]}
    self.assertAllClose(
        hist.history, expect_results, rtol=.1, atol=100.)
Exemplo n.º 8
0
def main(_):
    # Parse and override hparams
    config = hparams_config.get_detection_config(FLAGS.model_name)
    config.override(FLAGS.hparams)
    if FLAGS.num_epochs:  # NOTE: remove this flag after updating all docs.
        config.num_epochs = FLAGS.num_epochs

    # Parse image size in case it is in string format.
    config.image_size = utils.parse_image_size(config.image_size)

    if FLAGS.use_xla and FLAGS.strategy != 'tpu':
        tf.config.optimizer.set_jit(True)
        for gpu in tf.config.list_physical_devices('GPU'):
            tf.config.experimental.set_memory_growth(gpu, True)

    if FLAGS.debug:
        tf.config.experimental_run_functions_eagerly(True)
        tf.debugging.set_log_device_placement(True)
        tf.random.set_seed(111111)
        logging.set_verbosity(logging.DEBUG)

    if FLAGS.strategy == 'tpu':
        tpu_cluster_resolver = tf.distribute.cluster_resolver.TPUClusterResolver(
            FLAGS.tpu, zone=FLAGS.tpu_zone, project=FLAGS.gcp_project)
        tf.config.experimental_connect_to_cluster(tpu_cluster_resolver)
        tf.tpu.experimental.initialize_tpu_system(tpu_cluster_resolver)
        ds_strategy = tf.distribute.TPUStrategy(tpu_cluster_resolver)
        logging.info('All devices: %s', tf.config.list_logical_devices('TPU'))
    elif FLAGS.strategy == 'gpus':
        ds_strategy = tf.distribute.MirroredStrategy()
        logging.info('All devices: %s', tf.config.list_physical_devices('GPU'))
    else:
        if tf.config.list_physical_devices('GPU'):
            ds_strategy = tf.distribute.OneDeviceStrategy('device:GPU:0')
        else:
            ds_strategy = tf.distribute.OneDeviceStrategy('device:CPU:0')

    # Check data path
    if FLAGS.mode in (
            'train', 'train_and_eval') and FLAGS.training_file_pattern is None:
        raise RuntimeError(
            'You must specify --training_file_pattern for training.')
    if FLAGS.mode in ('eval', 'train_and_eval'):
        if FLAGS.validation_file_pattern is None:
            raise RuntimeError('You must specify --validation_file_pattern '
                               'for evaluation.')

    params = dict(config.as_dict(),
                  model_name=FLAGS.model_name,
                  iterations_per_loop=FLAGS.iterations_per_loop,
                  model_dir=FLAGS.model_dir,
                  num_examples_per_epoch=FLAGS.num_examples_per_epoch,
                  strategy=FLAGS.strategy,
                  batch_size=FLAGS.batch_size //
                  ds_strategy.num_replicas_in_sync,
                  num_shards=ds_strategy.num_replicas_in_sync,
                  val_json_file=FLAGS.val_json_file,
                  testdev_dir=FLAGS.testdev_dir,
                  mode=FLAGS.mode)

    # set mixed precision policy by keras api.
    precision = utils.get_precision(params['strategy'],
                                    params['mixed_precision'])
    policy = tf.keras.mixed_precision.experimental.Policy(precision)
    tf.keras.mixed_precision.experimental.set_policy(policy)

    def get_dataset(is_training, params):
        file_pattern = (FLAGS.training_file_pattern
                        if is_training else FLAGS.validation_file_pattern)
        return dataloader.InputReader(
            file_pattern,
            is_training=is_training,
            use_fake_data=FLAGS.use_fake_data,
            max_instances_per_image=config.max_instances_per_image)(params)

    with ds_strategy.scope():
        model = train_lib.EfficientDetNetTrain(params['model_name'], config)
        height, width = utils.parse_image_size(params['image_size'])
        model.build((params['batch_size'], height, width, 3))
        model.compile(
            optimizer=train_lib.get_optimizer(params),
            loss={
                'box_loss':
                train_lib.BoxLoss(params['delta'],
                                  reduction=tf.keras.losses.Reduction.NONE),
                'box_iou_loss':
                train_lib.BoxIouLoss(params['iou_loss_type'],
                                     params['min_level'],
                                     params['max_level'],
                                     params['num_scales'],
                                     params['aspect_ratios'],
                                     params['anchor_scale'],
                                     params['image_size'],
                                     reduction=tf.keras.losses.Reduction.NONE),
                'class_loss':
                train_lib.FocalLoss(params['alpha'],
                                    params['gamma'],
                                    label_smoothing=params['label_smoothing'],
                                    reduction=tf.keras.losses.Reduction.NONE)
            })
    ckpt_path = tf.train.latest_checkpoint(FLAGS.model_dir)
    if ckpt_path:
        model.load_weights(ckpt_path)
    model.freeze_vars(params['var_freeze_expr'])
    model.fit(get_dataset(True, params=params),
              steps_per_epoch=FLAGS.num_examples_per_epoch,
              callbacks=train_lib.get_callbacks(params, FLAGS.profile),
              validation_data=get_dataset(False, params=params),
              validation_steps=FLAGS.eval_samples)
    model.save_weights(os.path.join(FLAGS.model_dir, 'model'))
Exemplo n.º 9
0
    def test_train(self):
        tf.random.set_seed(1111)
        config = hparams_config.get_detection_config('efficientdet-d0')
        config.heads = ['object_detection', 'segmentation']
        config.batch_size = 1
        config.num_examples_per_epoch = 1
        config.model_dir = tempfile.mkdtemp()
        config.steps_per_epoch = 1
        x = tf.ones((1, 512, 512, 3))
        labels = {
            'box_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 36))
            for i in range(3, 8)
        }
        labels.update({
            'cls_targets_%d' % i: tf.ones((1, 512 // 2**i, 512 // 2**i, 9),
                                          dtype=tf.int32)
            for i in range(3, 8)
        })
        labels.update({'image_masks': tf.ones((1, 128, 128, 1))})
        labels.update({'mean_num_positives': tf.constant([10.0])})

        params = config.as_dict()
        params['num_shards'] = 1
        model = train_lib.EfficientDetNetTrain(config=config)
        model.build((1, 512, 512, 3))
        model.compile(
            optimizer=train_lib.get_optimizer(params),
            loss={
                'box_loss':
                train_lib.BoxLoss(params['delta'],
                                  reduction=tf.keras.losses.Reduction.NONE),
                'box_iou_loss':
                train_lib.BoxIouLoss(params['iou_loss_type'],
                                     params['min_level'],
                                     params['max_level'],
                                     params['num_scales'],
                                     params['aspect_ratios'],
                                     params['anchor_scale'],
                                     params['image_size'],
                                     reduction=tf.keras.losses.Reduction.NONE),
                'class_loss':
                train_lib.FocalLoss(params['alpha'],
                                    params['gamma'],
                                    label_smoothing=params['label_smoothing'],
                                    reduction=tf.keras.losses.Reduction.NONE),
                'seg_loss':
                tf.keras.losses.SparseCategoricalCrossentropy(from_logits=True)
            })

        # Test single-batch
        outputs = model.train_on_batch(x, labels, return_dict=True)
        expect_results = {
            'loss': [26278.3, 5061.9, 425.5, 1.217],
            'det_loss': 26277.033203125,
            'cls_loss': 5060.716796875,
            'box_loss': 424.3263244628906,
            'gnorm': 5873.78759765625,
            'seg_loss': 1.2215478420257568,
        }
        self.assertAllClose(outputs, expect_results, rtol=.1, atol=100.)
        outputs = model.test_on_batch(x, labels, return_dict=True)
        expect_results = {
            'loss': [26278.3, 5061.9, 425.5, 1.217],
            'det_loss': 26078.49609375,
            'cls_loss': 5063.3759765625,
            'box_loss': 420.30242919921875,
            'seg_loss': 1.2299377918243408,
        }
        self.assertAllClose(outputs, expect_results, rtol=.1, atol=100.)

        # Test fit.
        hist = model.fit(x,
                         labels,
                         steps_per_epoch=1,
                         epochs=1,
                         callbacks=train_lib.get_callbacks(params))

        self.assertAllClose(hist.history['loss'],
                            [[26067, 5057.5, 421.4, 1.2]],
                            rtol=.1,
                            atol=10.)
        self.assertAllClose(hist.history['det_loss'], [26061.],
                            rtol=.1,
                            atol=10.)
        self.assertAllClose(hist.history['cls_loss'], [5058.],
                            rtol=.1,
                            atol=10.)
        self.assertAllClose(hist.history['box_loss'], [420.],
                            rtol=.1,
                            atol=100.)
        self.assertAllClose(hist.history['seg_loss'], [1.2299],
                            rtol=.1,
                            atol=100.)
Exemplo n.º 10
0
def main(_):
  # Parse and override hparams
  config = hparams_config.get_detection_config(FLAGS.model_name)
  config.override(FLAGS.hparams)
  if FLAGS.num_epochs:  # NOTE: remove this flag after updating all docs.
    config.num_epochs = FLAGS.num_epochs

  # Parse image size in case it is in string format.
  config.image_size = utils.parse_image_size(config.image_size)

  if FLAGS.use_xla and FLAGS.strategy != 'tpu':
    tf.config.optimizer.set_jit(True)
    for gpu in tf.config.list_physical_devices('GPU'):
      tf.config.experimental.set_memory_growth(gpu, True)

  if FLAGS.debug:
    tf.config.run_functions_eagerly(True)
    tf.debugging.set_log_device_placement(True)
    os.environ['TF_DETERMINISTIC_OPS'] = '1'
    tf.random.set_seed(FLAGS.tf_random_seed)
    logging.set_verbosity(logging.DEBUG)

  if FLAGS.strategy == 'tpu':
    tpu_cluster_resolver = tf.distribute.cluster_resolver.TPUClusterResolver(
        FLAGS.tpu, zone=FLAGS.tpu_zone, project=FLAGS.gcp_project)
    tf.config.experimental_connect_to_cluster(tpu_cluster_resolver)
    tf.tpu.experimental.initialize_tpu_system(tpu_cluster_resolver)
    ds_strategy = tf.distribute.TPUStrategy(tpu_cluster_resolver)
    logging.info('All devices: %s', tf.config.list_logical_devices('TPU'))
  elif FLAGS.strategy == 'gpus':
    ds_strategy = tf.distribute.MirroredStrategy()
    logging.info('All devices: %s', tf.config.list_physical_devices('GPU'))
  else:
    if tf.config.list_physical_devices('GPU'):
      ds_strategy = tf.distribute.OneDeviceStrategy('device:GPU:0')
    else:
      ds_strategy = tf.distribute.OneDeviceStrategy('device:CPU:0')

  steps_per_epoch = FLAGS.num_examples_per_epoch // FLAGS.batch_size
  params = dict(
      profile=FLAGS.profile,
      model_name=FLAGS.model_name,
      steps_per_execution=FLAGS.steps_per_execution,
      model_dir=FLAGS.model_dir,
      steps_per_epoch=steps_per_epoch,
      strategy=FLAGS.strategy,
      batch_size=FLAGS.batch_size,
      tf_random_seed=FLAGS.tf_random_seed,
      debug=FLAGS.debug,
      val_json_file=FLAGS.val_json_file,
      eval_samples=FLAGS.eval_samples,
      num_shards=ds_strategy.num_replicas_in_sync)
  config.override(params, True)
  # set mixed precision policy by keras api.
  precision = utils.get_precision(config.strategy, config.mixed_precision)
  policy = tf.keras.mixed_precision.Policy(precision)
  tf.keras.mixed_precision.set_global_policy(policy)

  def get_dataset(is_training, config):
    file_pattern = (
        FLAGS.train_file_pattern
        if is_training else FLAGS.val_file_pattern)
    if not file_pattern:
      raise ValueError('No matching files.')

    return dataloader.InputReader(
        file_pattern,
        is_training=is_training,
        use_fake_data=FLAGS.use_fake_data,
        max_instances_per_image=config.max_instances_per_image,
        debug=FLAGS.debug)(
            config.as_dict())

  with ds_strategy.scope():
    if config.model_optimizations:
      tfmot.set_config(config.model_optimizations.as_dict())
    if FLAGS.hub_module_url:
      model = train_lib.EfficientDetNetTrainHub(
          config=config, hub_module_url=FLAGS.hub_module_url)
    else:
      model = train_lib.EfficientDetNetTrain(config=config)
    model = setup_model(model, config)
    if FLAGS.pretrained_ckpt and not FLAGS.hub_module_url:
      ckpt_path = tf.train.latest_checkpoint(FLAGS.pretrained_ckpt)
      util_keras.restore_ckpt(model, ckpt_path, config.moving_average_decay)
    init_experimental(config)
    if 'train' in FLAGS.mode:
      val_dataset = get_dataset(False, config) if 'eval' in FLAGS.mode else None
      model.fit(
          get_dataset(True, config),
          epochs=config.num_epochs,
          steps_per_epoch=steps_per_epoch,
          callbacks=train_lib.get_callbacks(config.as_dict(), val_dataset),
          validation_data=val_dataset,
          validation_steps=(FLAGS.eval_samples // FLAGS.batch_size))
    else:
      # Continuous eval.
      for ckpt in tf.train.checkpoints_iterator(
          FLAGS.model_dir, min_interval_secs=180):
        logging.info('Starting to evaluate.')
        # Terminate eval job when final checkpoint is reached.
        try:
          current_epoch = int(os.path.basename(ckpt).split('-')[1])
        except IndexError:
          current_epoch = 0

        val_dataset = get_dataset(False, config)
        logging.info('start loading model.')
        model.load_weights(tf.train.latest_checkpoint(FLAGS.model_dir))
        logging.info('finish loading model.')
        coco_eval = train_lib.COCOCallback(val_dataset, 1)
        coco_eval.set_model(model)
        eval_results = coco_eval.on_epoch_end(current_epoch)
        logging.info('eval results for %s: %s', ckpt, eval_results)

        try:
          utils.archive_ckpt(eval_results, eval_results['AP'], ckpt)
        except tf.errors.NotFoundError:
          # Checkpoint might be not already deleted by the time eval finished.
          logging.info('Checkpoint %s no longer exists, skipping.', ckpt)

        if current_epoch >= config.num_epochs or not current_epoch:
          logging.info('Eval epoch %d / %d', current_epoch, config.num_epochs)
          break
Exemplo n.º 11
0
def main(_):
    # Parse and override hparams
    config = hparams_config.get_detection_config(FLAGS.model_name)
    config.override(FLAGS.hparams)
    if FLAGS.num_epochs:  # NOTE: remove this flag after updating all docs.
        config.num_epochs = FLAGS.num_epochs

    # Parse image size in case it is in string format.
    config.image_size = utils.parse_image_size(config.image_size)

    if FLAGS.use_xla and FLAGS.strategy != 'tpu':
        tf.config.optimizer.set_jit(True)
        for gpu in tf.config.list_physical_devices('GPU'):
            tf.config.experimental.set_memory_growth(gpu, True)

    if FLAGS.debug:
        tf.config.experimental_run_functions_eagerly(True)
        tf.debugging.set_log_device_placement(True)
        tf.random.set_seed(111111)
        logging.set_verbosity(logging.DEBUG)

    if FLAGS.strategy == 'tpu':
        tpu_cluster_resolver = tf.distribute.cluster_resolver.TPUClusterResolver(
            FLAGS.tpu, zone=FLAGS.tpu_zone, project=FLAGS.gcp_project)
        tf.config.experimental_connect_to_cluster(tpu_cluster_resolver)
        tf.tpu.experimental.initialize_tpu_system(tpu_cluster_resolver)
        ds_strategy = tf.distribute.TPUStrategy(tpu_cluster_resolver)
        logging.info('All devices: %s', tf.config.list_logical_devices('TPU'))
    elif FLAGS.strategy == 'gpus':
        ds_strategy = tf.distribute.MirroredStrategy()
        logging.info('All devices: %s', tf.config.list_physical_devices('GPU'))
    else:
        if tf.config.list_physical_devices('GPU'):
            ds_strategy = tf.distribute.OneDeviceStrategy('device:GPU:0')
        else:
            ds_strategy = tf.distribute.OneDeviceStrategy('device:CPU:0')

    steps_per_epoch = FLAGS.num_examples_per_epoch // FLAGS.batch_size
    params = dict(config.as_dict(),
                  profile=FLAGS.profile,
                  model_name=FLAGS.model_name,
                  iterations_per_loop=FLAGS.iterations_per_loop,
                  model_dir=FLAGS.model_dir,
                  steps_per_epoch=steps_per_epoch,
                  strategy=FLAGS.strategy,
                  batch_size=FLAGS.batch_size,
                  num_shards=ds_strategy.num_replicas_in_sync)

    # set mixed precision policy by keras api.
    precision = utils.get_precision(params['strategy'],
                                    params['mixed_precision'])
    policy = tf.keras.mixed_precision.experimental.Policy(precision)
    tf.keras.mixed_precision.experimental.set_policy(policy)

    def get_dataset(is_training, params):
        file_pattern = (FLAGS.training_file_pattern
                        if is_training else FLAGS.validation_file_pattern)
        if not file_pattern:
            raise ValueError('No matching files.')

        return dataloader.InputReader(
            file_pattern,
            is_training=is_training,
            use_fake_data=FLAGS.use_fake_data,
            max_instances_per_image=config.max_instances_per_image)(params)

    with ds_strategy.scope():
        model = train_lib.EfficientDetNetTrain(params['model_name'], config)
        model.compile(
            optimizer=train_lib.get_optimizer(params),
            loss={
                'box_loss':
                train_lib.BoxLoss(params['delta'],
                                  reduction=tf.keras.losses.Reduction.NONE),
                'box_iou_loss':
                train_lib.BoxIouLoss(params['iou_loss_type'],
                                     params['min_level'],
                                     params['max_level'],
                                     params['num_scales'],
                                     params['aspect_ratios'],
                                     params['anchor_scale'],
                                     params['image_size'],
                                     reduction=tf.keras.losses.Reduction.NONE),
                'class_loss':
                train_lib.FocalLoss(params['alpha'],
                                    params['gamma'],
                                    label_smoothing=params['label_smoothing'],
                                    reduction=tf.keras.losses.Reduction.NONE),
                'seg_loss':
                tf.keras.losses.SparseCategoricalCrossentropy(
                    from_logits=True, reduction=tf.keras.losses.Reduction.NONE)
            })

        if FLAGS.pretrained_ckpt:
            ckpt_path = tf.train.latest_checkpoint(FLAGS.pretrained_ckpt)
            util_keras.restore_ckpt(model, ckpt_path,
                                    params['moving_average_decay'])
        tf.io.gfile.makedirs(FLAGS.model_dir)
        if params['model_optimizations']:
            model_optimization.set_config(params['model_optimizations'])
        model.build((FLAGS.batch_size, *config.image_size, 3))
        model.fit(get_dataset(True, params=params),
                  epochs=params['num_epochs'],
                  steps_per_epoch=steps_per_epoch,
                  callbacks=train_lib.get_callbacks(params),
                  validation_data=get_dataset(False, params=params).repeat(),
                  validation_steps=(FLAGS.eval_samples // FLAGS.batch_size))
    model.save_weights(os.path.join(FLAGS.model_dir, 'ckpt-final'))