def center_crop_and_resize(img: ImageT,
bbox: BBox,
target_size: SizeT,
border: Optional[Union[int, Tuple[int,
...]]] = None,
interpolation=Image.BICUBIC) -> ImageT:
bbox_corners = bbox.as_corners()
paddings = np.concatenate((-bbox_corners[:2], bbox_corners[2:] - img.size))
max_padding = np.maximum(paddings, 0).max()
if max_padding > 0:
if border is None:
border = tuple(int(round(c)) for c in ImageStat.Stat(img).mean)
img = ImageOps.expand(img, border=max_padding, fill=border)
bbox_corners += max_padding
bbox_corners = tuple((bbox_corners).astype(int))
patch = img.crop(bbox_corners)
patch = patch.resize(target_size, interpolation)
return patch
class TestBBox(unittest.TestCase):
def setUp(self) -> None:
self.bbox = BBox(10, 20, 300, 400)
def test_negative_width(self):
with self.assertRaises(AssertionError):
BBox(100, 100, -10, 200)
def test_negative_height(self):
with self.assertRaises(AssertionError):
BBox(100, 100, 10, -200)
def test_center(self):
self.assertEqual(self.bbox.center.tolist(), [160, 220])
def test_size(self):
self.assertEqual(self.bbox.size.tolist(), [300, 400])
def test_set_size_negative(self):
with self.assertRaises(AssertionError):
self.bbox.size = np.asarray((-10, 100))
def test_set_size_float(self):
with self.assertRaises(AssertionError):
self.bbox.size = np.asarray((10.0, 100.0))
def test_corners_calculation(self):
self.assertEqual(self.bbox.as_corners().tolist(), [10, 20, 310, 420])
def test_top_left_bottom_right_calculation(self):
tl, br = self.bbox.as_tl_br()
self.assertEqual(tl.tolist(), [10, 20])
self.assertEqual(br.tolist(), [310, 420])
def test_x_y_width_height_calculation_zero_based(self):
self.assertEqual(self.bbox.as_xywh().tolist(), [10, 20, 300, 400])
def test_x_y_width_height_calculation_one_based(self):
self.assertEqual(self.bbox.as_xywh(False).tolist(), [11, 21, 300, 400])
def test_negative_width_scale_factor(self):
with self.assertRaises(AssertionError):
self.bbox.rescale(-0.5, 2)
def test_negative_height_scale_factor(self):
with self.assertRaises(AssertionError):
self.bbox.rescale(0.5, -2)
def test_center_shift(self):
bbox_shifted = self.bbox.shift(np.asarray((100, -100)), in_place=False)
self.assertEqual(bbox_shifted.center.tolist(), [260, 120])
def test_center_shift_inplace(self):
bbox_shifted = self.bbox.shift(np.asarray((100, -100)), in_place=True)
self.assertTrue(bbox_shifted is None)
self.assertEqual(self.bbox.center.tolist(), [260, 120])
def test_float_center_shift(self):
with self.assertRaises(AssertionError):
self.bbox.shift(np.asarray((2.0, -5.5)))
def test_upscale_twice(self):
scale = 2
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=False)
self.assertEqual(bbox_rescaled.size.tolist(), [600, 800])
def test_downscale_twice(self):
scale = 0.5
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=False)
self.assertEqual(bbox_rescaled.size.tolist(), [150, 200])
def test_no_scale_change(self):
scale = 1
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=False)
self.assertEqual(bbox_rescaled.size.tolist(), [300, 400])
def test_upscale_twice_inplace(self):
scale = 2
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=True)
self.assertTrue(bbox_rescaled is None)
self.assertEqual(self.bbox.size.tolist(), [600, 800])
def test_downscale_twice_inplace(self):
scale = 0.5
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=True)
self.assertTrue(bbox_rescaled is None)
self.assertEqual(self.bbox.size.tolist(), [150, 200])
def test_no_scale_change_inplace(self):
scale = 1
bbox_rescaled = self.bbox.rescale(scale, scale, in_place=True)
self.assertTrue(bbox_rescaled is None)
self.assertEqual(self.bbox.size.tolist(), [300, 400])
def test_repr_str(self):
self.assertEqual(repr(self.bbox), 'BBox(10,20,300,400)')
def test_build_from_repr(self):
bbox_new = eval(repr(self.bbox))
self.assertEqual(self.bbox.center.tolist(), bbox_new.center.tolist())
self.assertEqual(self.bbox.size.tolist(), bbox_new.size.tolist())