transferring functionalities from main.py to src

src/utils/image_utils.py

@@ -0,0 +1,44 @@
+import cv2
+import numpy as np
+from PIL import Image
+
+
+def pil_to_cv2(pil_image: Image.Image) -> np.ndarray:
+    """Convert PIL Image to OpenCV image (always BGR 3-channel when color)."""
+    mode = pil_image.mode
+    arr = np.array(pil_image)
+
+    # Handle grayscale
+    if mode in ("1", "L"):
+        # arr is 2D. Convert to 3-channel BGR for downstream ops expecting color
+        return cv2.cvtColor(arr, cv2.COLOR_GRAY2BGR)
+
+    # Handle images with alpha channel by dropping alpha for processing
+    if mode in ("LA", "RGBA"):
+        # Convert to RGB first
+        pil_rgb = pil_image.convert("RGB")
+        arr = np.array(pil_rgb)
+        return cv2.cvtColor(arr, cv2.COLOR_RGB2BGR)
+
+    # Assume RGB-like
+    if arr.ndim == 3 and arr.shape[2] == 3:
+        return cv2.cvtColor(arr, cv2.COLOR_RGB2BGR)
+
+    # Fallback: if still single-channel, expand to BGR
+    if arr.ndim == 2:
+        return cv2.cvtColor(arr, cv2.COLOR_GRAY2BGR)
+
+    return arr
+
+
+def cv2_to_pil(cv_image: np.ndarray) -> Image.Image:
+    """Convert OpenCV image (BGR or GRAY) to PIL Image (RGB or L)."""
+    if cv_image.ndim == 2:
+        return Image.fromarray(cv_image)
+    rgb = cv2.cvtColor(cv_image, cv2.COLOR_BGR2RGB)
+    return Image.fromarray(rgb)
+
+
+def clamp_int(value: float, min_value: int = 0, max_value: int = 255) -> int:
+    return int(max(min_value, min(max_value, round(value))))
+