# Copyright 2015 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 draw_bounding_box_op."""
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import numpy as np
import tensorflow as tf


class DrawBoundingBoxOpTest(tf.test.TestCase):

  def _fillBorder(self, image, color):
    """Fill the border of the image.

    Args:
      image: Numpy array of shape [height, width, depth].
      color: Numpy color of shape [depth] and either contents RGB/RGBA.

    Returns:
      image of original shape with border filled with "color".

    Raises:
      ValueError: Depths of image and color don"t match.
    """
    height, width, depth = image.shape
    if depth != color.shape[0]:
      raise ValueError("Image (%d) and color (%d) depths must match." %
                       (depth, color.shape[0]))
    image[0:height, 0, 0:depth] = color
    image[0:height, width - 1, 0:depth] = color
    image[0, 0:width, 0:depth] = color
    image[height - 1, 0:width, 0:depth] = color
    return image

  def _testDrawBoundingBoxColorCycling(self, img):
    """Tests if cycling works appropriately.

    Args:
      img: 3-D numpy image on which to draw.
    """
    # THIS TABLE MUST MATCH draw_bounding_box_op.cc
    color_table = np.asarray([[1, 1, 0, 1], [0, 0, 1, 1], [1, 0, 0, 1],
                              [0, 1, 0, 1], [0.5, 0, 0.5, 1],
                              [0.5, 0.5, 0, 1], [0.5, 0, 0, 1],
                              [0, 0, 0.5, 1], [0, 1, 1, 1],
                              [1, 0, 1, 1]])
    assert len(img.shape) == 3
    depth = img.shape[2]
    assert depth <= color_table.shape[1]
    assert depth == 1 or depth == 3 or depth == 4
    ## Set red channel to 1 if image is GRY.
    if depth == 1:
      color_table[:, 0] = 1
    num_colors = color_table.shape[0]
    for num_boxes in range(1, num_colors + 2):
      # Generate draw_bounding_box_op drawn image
      image = np.copy(img)
      color = color_table[(num_boxes - 1) % num_colors, 0:depth]
      test_drawn_image = self._fillBorder(image, color)
      bboxes = np.asarray([0, 0, 1, 1])
      bboxes = np.vstack([bboxes for _ in range(num_boxes)])
      bboxes = tf.to_float(bboxes)
      bboxes = tf.expand_dims(bboxes, 0)
      image = tf.convert_to_tensor(image)
      image = tf.image.convert_image_dtype(image, tf.float32)
      image = tf.expand_dims(image, 0)
      image = tf.image.draw_bounding_boxes(image, bboxes)
      with self.test_session(use_gpu=False) as sess:
        op_drawn_image = np.squeeze(sess.run(image), 0)
        self.assertAllEqual(test_drawn_image, op_drawn_image)

  def testDrawBoundingBoxRGBColorCycling(self):
    """Test if RGB color cycling works correctly."""
    image = np.zeros([10, 10, 3], "float32")
    self._testDrawBoundingBoxColorCycling(image)

  def testDrawBoundingBoxRGBAColorCycling(self):
    """Test if RGBA color cycling works correctly."""
    image = np.zeros([10, 10, 4], "float32")
    self._testDrawBoundingBoxColorCycling(image)

  def testDrawBoundingBoxGRY(self):
    """Test if drawing bounding box on a GRY image works."""
    image = np.zeros([4, 4, 1], "float32")
    self._testDrawBoundingBoxColorCycling(image)

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