1# Copyright 2016 The Android Open Source Project
2#
3# Licensed under the Apache License, Version 2.0 (the "License");
4# you may not use this file except in compliance with the License.
5# You may obtain a copy of the License at
6#
7#      http://www.apache.org/licenses/LICENSE-2.0
8#
9# Unless required by applicable law or agreed to in writing, software
10# distributed under the License is distributed on an "AS IS" BASIS,
11# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12# See the License for the specific language governing permissions and
13# limitations under the License.
14"""Test lens shading and color uniformity with diffuser over camera."""
15
16
17import logging
18import math
19import os.path
20
21import cv2
22from mobly import test_runner
23import numpy
24
25import its_base_test
26import camera_properties_utils
27import capture_request_utils
28import image_processing_utils
29import its_session_utils
30
31_NAME = os.path.basename(__file__).split('.')[0]
32_NSEC_TO_MSEC = 1E-6
33
34# List to create NUM-1 blocks around the center block for sampling grid in image
35_NUM_RADIUS = 8
36_BLOCK_R = 1/2/(_NUM_RADIUS*2-1)  # 'radius' of block (x/2 & y/2 in rel values)
37_BLOCK_POSITION_LIST = numpy.arange(_BLOCK_R, 1/2, _BLOCK_R*2)
38
39# Thresholds for PASS/FAIL
40_THRESH_SHADING_CT = 0.9  # len shading allowance for center
41_THRESH_SHADING_CN = 0.6  # len shading allowance for corner
42_THRESH_SHADING_HIGH = 0.2  # max allowed % for patch to be brighter than center
43_THRESH_UNIFORMITY = 0.2  # uniformity allowance
44
45# cv2 drawing colors
46_CV2_RED = (1, 0, 0)   # blocks failed the test
47_CV2_GREEN = (0, 0.7, 0.3)   # blocks passed the test
48
49
50def _calc_block_lens_shading_thresh_l(
51    block_center_x, block_center_y, center_luma, img_w, img_h, dist_max):
52  dist_to_img_center = math.sqrt(pow(abs(block_center_x-0.5)*img_w, 2) +
53                                 pow(abs(block_center_y-0.5)*img_h, 2))
54  return ((_THRESH_SHADING_CT - _THRESH_SHADING_CN) *
55          (1 - dist_to_img_center/dist_max) + _THRESH_SHADING_CN) * center_luma
56
57
58def _calc_color_plane_ratios(img_rgb):
59  """Calculate R/G and B/G ratios."""
60  img_g_plus_delta = img_rgb[:, :, 1] + 0.001  # in case G channel has 0 value.
61  img_r_g = img_rgb[:, :, 0] / img_g_plus_delta
62  img_b_g = img_rgb[:, :, 2] / img_g_plus_delta
63  return img_r_g, img_b_g
64
65
66def _create_block_center_vals(block_center):
67  """Create lists of x and y values for sub-block centers."""
68  num_sample = int(((1-block_center*2)/_BLOCK_R/2 + 1).item())
69  center_xs = numpy.concatenate(
70      (numpy.arange(block_center, 1-block_center+_BLOCK_R, _BLOCK_R*2),
71       block_center*numpy.ones((num_sample-1)),
72       (1-block_center)*numpy.ones((num_sample-1)),
73       numpy.arange(block_center, 1-block_center+_BLOCK_R, _BLOCK_R*2)))
74  center_ys = numpy.concatenate(
75      (block_center*numpy.ones(num_sample+1),
76       numpy.arange(block_center+_BLOCK_R*2, 1-block_center, _BLOCK_R*2),
77       numpy.arange(block_center+_BLOCK_R*2, 1-block_center, _BLOCK_R*2),
78       (1-block_center)*numpy.ones(num_sample+1)))
79  return zip(center_xs, center_ys)
80
81
82def _assert_results(ls_test_failed, cu_test_failed, center_luma, ls_thresh_h):
83  """Check the lens shading and color uniformity results."""
84  if ls_test_failed:
85    logging.error('Lens shading test summary')
86    logging.error('Center block average Y value: %.3f', center_luma)
87    logging.error('Blocks failed in the lens shading test:')
88    for block in ls_test_failed:
89      top, bottom, left, right = block['position']
90      logging.error('Block[top: %d, bottom: %d, left: %d, right: %d]; '
91                    'avg Y value: %.3f; valid range: %.3f ~ %.3f', top, bottom,
92                    left, right, block['val'], block['thresh_l'], ls_thresh_h)
93  if cu_test_failed:
94    logging.error('Color uniformity test summary')
95    logging.error('Valid color uniformity range: 0 ~ %.2f', _THRESH_UNIFORMITY)
96    logging.error('Areas that failed the color uniformity test:')
97    for rd in cu_test_failed:
98      logging.error('Radius position: %.3f; R/G uniformity: %.3f; B/G '
99                    'uniformity: %.3f', rd['position'], rd['uniformity_r_g'],
100                    rd['uniformity_b_g'])
101  if ls_test_failed:
102    raise AssertionError('Lens shading test failed.')
103  if cu_test_failed:
104    raise AssertionError('Color uniformity test failed.')
105
106
107def _draw_legend(img, texts, text_org, font_scale, text_offset, color,
108                 line_width):
109  """Draw legend on an image.
110
111  Args:
112    img: Numpy float image array in RGB, with pixel values in [0,1].
113    texts: List of legends. Each element in the list is a line of legend.
114    text_org: Tuple of the bottom left corner of the text position in
115              pixels, horizontal and vertical.
116    font_scale: Float number. Font scale of the basic font size.
117    text_offset: Text line width in pixels.
118    color: Text color in rgb value.
119    line_width: Text line width in pixels.
120  """
121  for text in texts:
122    cv2.putText(img, text, (text_org[0], text_org[1]),
123                cv2.FONT_HERSHEY_SIMPLEX, font_scale, color, line_width)
124    text_org[1] += text_offset
125
126
127class LensShadingAndColorUniformityTest(its_base_test.ItsBaseTest):
128  """Test lens shading correction and uniform scene is evenly distributed.
129
130  Test runs with a diffuser (manually) placed in front of the camera.
131  Performs this test on a YUV frame with auto 3A. Lens shading is evaluated
132  based on the Y channel. Measure the average Y value for each sample block
133  specified, and then determine PASS/FAIL by comparing with the center Y value.
134
135  Evaluates the color uniformity in R/G and B/G color space. At specified
136  radius of the image, the variance of R/G and B/G values need to be less than
137  a threshold in order to pass the test.
138  """
139
140  def test_lens_shading_and_color_uniformity(self):
141
142    with its_session_utils.ItsSession(
143        device_id=self.dut.serial,
144        camera_id=self.camera_id,
145        hidden_physical_id=self.hidden_physical_id) as cam:
146      props = cam.get_camera_properties()
147      props = cam.override_with_hidden_physical_camera_props(props)
148      debug_mode = self.debug_mode
149      name_with_log_path = os.path.join(self.log_path, _NAME)
150
151      # Check SKIP conditions.
152      camera_properties_utils.skip_unless(
153          camera_properties_utils.ae_lock(props) and
154          camera_properties_utils.awb_lock(props))
155
156      if camera_properties_utils.read_3a(props):
157        # Converge 3A and get the estimates.
158        sens, exp, awb_gains, awb_xform, _ = cam.do_3a(
159            get_results=True, do_af=False, lock_ae=True, lock_awb=True)
160        logging.debug('AE sensitivity: %d, exp: %dms', sens, exp*_NSEC_TO_MSEC)
161        logging.debug('AWB gains: %s', str(awb_gains))
162        logging.debug('AWB transform: %s', str(awb_xform))
163
164      req = capture_request_utils.auto_capture_request()
165      w, h = capture_request_utils.get_available_output_sizes('yuv', props)[0]
166      out_surface = {'format': 'yuv', 'width': w, 'height': h}
167      if debug_mode:
168        out_surfaces = [{'format': 'raw'}, out_surface]
169        cap_raw, cap = cam.do_capture(req, out_surfaces)
170        img_raw = image_processing_utils.convert_capture_to_rgb_image(
171            cap_raw, props=props)
172        image_processing_utils.write_image(
173            img_raw, f'{name_with_log_path}_raw.png', True)
174        logging.debug('Captured RAW %dx%d', img_raw.shape[1], img_raw.shape[0])
175      else:
176        cap = cam.do_capture(req, out_surface)
177      logging.debug('Captured YUV %dx%d', w, h)
178      # Get Y channel
179      img_y = image_processing_utils.convert_capture_to_planes(cap)[0]
180      image_processing_utils.write_image(
181          img_y, f'{name_with_log_path}_y_plane.png', True)
182      # Convert RGB image & calculate R/G, R/B ratioed images
183      img_rgb = image_processing_utils.convert_capture_to_rgb_image(cap)
184      img_r_g, img_b_g = _calc_color_plane_ratios(img_rgb)
185
186      # Make copies for images with legends and set legend parameters.
187      img_lens_shading = numpy.copy(img_rgb)
188      img_uniformity = numpy.copy(img_rgb)
189      line_width = max(2, int(max(h, w)/500))  # line width of legend
190      font_scale = line_width / 7.0   # font scale of the basic font size
191      font_line_width = int(line_width/2)
192      text_height = cv2.getTextSize('gf', cv2.FONT_HERSHEY_SIMPLEX,
193                                    font_scale, line_width)[0][1]
194      text_offset = int(text_height*1.5)
195
196      # Calculate center block average Y, R/G, and B/G values.
197      top = int((0.5-_BLOCK_R)*h)
198      bottom = int((0.5+_BLOCK_R)*h)
199      left = int((0.5-_BLOCK_R)*w)
200      right = int((0.5+_BLOCK_R)*w)
201      center_luma = numpy.mean(img_y[top:bottom, left:right])
202      center_r_g = numpy.mean(img_r_g[top:bottom, left:right])
203      center_b_g = numpy.mean(img_b_g[top:bottom, left:right])
204
205      # Add center patch legend to lens shading and color uniformity images
206      cv2.rectangle(img_lens_shading, (left, top), (right, bottom), _CV2_GREEN,
207                    line_width)
208      _draw_legend(img_lens_shading, [f'Y: {center_luma}:.2f'],
209                   [left+text_offset, bottom-text_offset],
210                   font_scale, text_offset, _CV2_GREEN, font_line_width)
211
212      cv2.rectangle(img_uniformity, (left, top), (right, bottom), _CV2_GREEN,
213                    line_width)
214      _draw_legend(img_uniformity,
215                   [f'R/G: {center_r_g}:.2f', f'B/G: {center_b_g}:.2f'],
216                   [left+text_offset, bottom-text_offset*2],
217                   font_scale, text_offset, _CV2_GREEN, font_line_width)
218
219      # Evaluate Y, R/G, and B/G for each block
220      ls_test_failed = []
221      cu_test_failed = []
222      ls_thresh_h = center_luma * (1 + _THRESH_SHADING_HIGH)
223      dist_max = math.sqrt(pow(w, 2)+pow(h, 2))/2
224      for position in _BLOCK_POSITION_LIST:
225        # Create sample block centers' positions in all directions around center
226        block_centers = _create_block_center_vals(position)
227
228        blocks_info = []
229        max_r_g = 0
230        min_r_g = float('inf')
231        max_b_g = 0
232        min_b_g = float('inf')
233        for block_center_x, block_center_y in block_centers:
234          top = int((block_center_y-_BLOCK_R)*h)
235          bottom = int((block_center_y+_BLOCK_R)*h)
236          left = int((block_center_x-_BLOCK_R)*w)
237          right = int((block_center_x+_BLOCK_R)*w)
238
239          # Compute block average values and running mins and maxes
240          block_y = numpy.mean(img_y[top:bottom, left:right])
241          block_r_g = numpy.mean(img_r_g[top:bottom, left:right])
242          block_b_g = numpy.mean(img_b_g[top:bottom, left:right])
243          max_r_g = max(max_r_g, block_r_g)
244          min_r_g = min(min_r_g, block_r_g)
245          max_b_g = max(max_b_g, block_b_g)
246          min_b_g = min(min_b_g, block_b_g)
247          blocks_info.append({'position': [top, bottom, left, right],
248                              'block_r_g': block_r_g,
249                              'block_b_g': block_b_g})
250          # Check lens shading
251          ls_thresh_l = _calc_block_lens_shading_thresh_l(
252              block_center_x, block_center_y, center_luma, w, h, dist_max)
253
254          if not ls_thresh_h > block_y > ls_thresh_l:
255            ls_test_failed.append({'position': [top, bottom, left, right],
256                                   'val': block_y,
257                                   'thresh_l': ls_thresh_l})
258            legend_color = _CV2_RED
259          else:
260            legend_color = _CV2_GREEN
261
262          # Overlay legend rectangle on lens shading image.
263          text_bottom = bottom - text_offset
264          cv2.rectangle(img_lens_shading, (left, top), (right, bottom),
265                        legend_color, line_width)
266          _draw_legend(img_lens_shading, [f'Y: {block_y:.2f}'],
267                       [left+text_offset, text_bottom], font_scale,
268                       text_offset, legend_color, int(line_width/2))
269
270        # Check color uniformity
271        uniformity_r_g = (max_r_g-min_r_g) / center_r_g
272        uniformity_b_g = (max_b_g-min_b_g) / center_b_g
273        if (uniformity_r_g > _THRESH_UNIFORMITY or
274            uniformity_b_g > _THRESH_UNIFORMITY):
275          cu_test_failed.append({'position': position,
276                                 'uniformity_r_g': uniformity_r_g,
277                                 'uniformity_b_g': uniformity_b_g})
278          legend_color = _CV2_RED
279        else:
280          legend_color = _CV2_GREEN
281
282        # Overlay legend blocks on uniformity image based on PASS/FAIL above.
283        for block in blocks_info:
284          top, bottom, left, right = block['position']
285          cv2.rectangle(img_uniformity, (left, top), (right, bottom),
286                        legend_color, line_width)
287          texts = [f"R/G: {block['block_r_g']:.2f}",
288                   f"B/G: {block['block_b_g']:.2f}"]
289          text_bottom = bottom - text_offset * 2
290          _draw_legend(img_uniformity, texts,
291                       [left+text_offset, text_bottom], font_scale,
292                       text_offset, legend_color, font_line_width)
293
294      # Save images
295      image_processing_utils.write_image(
296          img_uniformity, f'{name_with_log_path}_color_uniformity_result.png',
297          True)
298      image_processing_utils.write_image(
299          img_lens_shading, f'{name_with_log_path}_lens_shading_result.png',
300          True)
301
302      # Assert results
303      _assert_results(ls_test_failed, cu_test_failed, center_luma, ls_thresh_h)
304
305
306if __name__ == '__main__':
307  test_runner.main()
308