Better crop

sbrunner · Apr 12, 2019 · 4a584c5 · 4a584c5
1 parent 617dded
commit 4a584c5
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Showing 2 changed files with 9 additions and 19 deletions.
diff --git a/process b/process
@@ -39,25 +39,11 @@ def crop_image(  # pylint: disable=too-many-arguments
         image: np.ndarray, x: int, y: int, width: int, height: int,
         background: Union[Tuple[int], Tuple[int, int, int]]
 ) -> np.ndarray:
-    if x < 0:
-        indices = np.zeros(-x, dtype=int)
-        image = np.insert(image, indices, background, axis=1)
-        x = 0
-    if y < 0:
-        indices = np.zeros(-y, dtype=int)
-        image = np.insert(image, indices, background, axis=0)
-        y = 0
-
-    overflow_x = x + width - image.shape[1]
-    if overflow_x > 0:
-        indices = np.zeros(overflow_x, dtype=int) + image.shape[1]
-        image = np.insert(image, indices, background, axis=1)
-    overflow_y = y + height - image.shape[0]
-    if overflow_y > 0:
-        indices = np.zeros(overflow_y, dtype=int) + int(image.shape[0])
-        image = np.insert(image, indices, background, axis=0)
-
-    return image[y:y + height, x:x + width]
+    matrice = np.array([
+        [1.0, 0.0, -x],
+        [0.0, 1.0, -y],
+    ])
+    return cv2.warpAffine(image, matrice, (int(round(width)), int(round(height))), borderValue=background)
 
 
 class Context:  # pylint: disable=too-many-instance-attributes

diff --git a/tests/test_process.py b/tests/test_process.py
@@ -48,6 +48,8 @@ def check_image(root_folder, image, name):
 def test_crop():
     image = load_image('image-1.png')
     root_folder = '/results/crop'
+    if not os.path.exists(root_folder):
+        os.makedirs(root_folder)
     check_image(root_folder, process.crop_image(image, 100, 0, 100, 300, (255, 255, 255)), 'crop-1')
     check_image(root_folder, process.crop_image(image, 0, 100, 300, 100, (255, 255, 255)), 'crop-2')
     check_image(root_folder, process.crop_image(image, 100, -100, 100, 200, (255, 255, 255)), 'crop-3')
@@ -59,6 +61,8 @@ def test_crop():
 def test_rotate():
     image = load_image('image-1.png')
     root_folder = '/results/rotate'
+    if not os.path.exists(root_folder):
+        os.makedirs(root_folder)
     image = process.crop_image(image, 0, 50, 300, 200, (255, 255, 255))
     check_image(root_folder, process.rotate_image(image, 10, (255, 255, 255)), 'rotate-1')
     check_image(root_folder, process.rotate_image(image, -10, (255, 255, 255)), 'rotate-2')