bugfix in slicer

src/split/slicer.py

@@ -30,9 +30,19 @@ def load_image(path: Path) -> np.ndarray:
     image = cv2.imread(str(path), cv2.IMREAD_UNCHANGED)
     if image is None:
         raise ValueError(f"Не удалось загрузить изображение: {path}")
+    if image.ndim == 3 and image.shape[2] == 4:
+        image = _rgba_to_white_bg(image)
     return image
 
 
+def _rgba_to_white_bg(image: np.ndarray) -> np.ndarray:
+    b, g, r, a = cv2.split(image)
+    alpha = a.astype(np.float32) / 255.0
+    bgr = cv2.merge([b, g, r])
+    composite = bgr * alpha[..., None] + 255.0 * (1.0 - alpha[..., None])
+    return composite.astype(np.uint8)
+
+
 def rotate_image(image: np.ndarray, degrees: int) -> np.ndarray:
     if degrees == 90:
         return cv2.rotate(image, cv2.ROTATE_90_CLOCKWISE)