image_resizer_builder_test.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.
# ==============================================================================

"""Tests for object_detection.builders.image_resizer_builder."""
import tensorflow as tf
from google.protobuf import text_format
from object_detection.builders import image_resizer_builder
from object_detection.protos import image_resizer_pb2


class ImageResizerBuilderTest(tf.test.TestCase):

  def _shape_of_resized_random_image_given_text_proto(
      self, input_shape, text_proto):
    image_resizer_config = image_resizer_pb2.ImageResizer()
    text_format.Merge(text_proto, image_resizer_config)
    image_resizer_fn = image_resizer_builder.build(image_resizer_config)
    images = tf.to_float(tf.random_uniform(
        input_shape, minval=0, maxval=255, dtype=tf.int32))
    resized_images = image_resizer_fn(images)
    with self.test_session() as sess:
      return sess.run(resized_images).shape

  def test_built_keep_aspect_ratio_resizer_returns_expected_shape(self):
    image_resizer_text_proto = """
      keep_aspect_ratio_resizer {
        min_dimension: 10
        max_dimension: 20
      }
    """
    input_shape = (50, 25, 3)
    expected_output_shape = (20, 10, 3)
    output_shape = self._shape_of_resized_random_image_given_text_proto(
        input_shape, image_resizer_text_proto)
    self.assertEqual(output_shape, expected_output_shape)

  def test_built_fixed_shape_resizer_returns_expected_shape(self):
    image_resizer_text_proto = """
      fixed_shape_resizer {
        height: 10
        width: 20
      }
    """
    input_shape = (50, 25, 3)
    expected_output_shape = (10, 20, 3)
    output_shape = self._shape_of_resized_random_image_given_text_proto(
        input_shape, image_resizer_text_proto)
    self.assertEqual(output_shape, expected_output_shape)

  def test_raises_error_on_invalid_input(self):
    invalid_input = 'invalid_input'
    with self.assertRaises(ValueError):
      image_resizer_builder.build(invalid_input)


if __name__ == '__main__':
  tf.test.main()