Update preprocess.py

preprocess.py

@@ -1,6 +1,13 @@
 import cv2
+import numpy as np
 
-def unsharp_masking(img):
-    gaussian = cv2.GaussianBlur(img, (0, 0), 2.0)
-    img = cv2.addWeighted(img, 2.0, gaussian, -1.0, 0)
-    return img
+def unsharp_masking(img, kernel_size=5, threshold=2.0):
+    if kernel_size % 2 == 0:
+        kernel_size += 1  # Ensure the kernel size is odd
+    gaussian = cv2.GaussianBlur(img, (kernel_size, kernel_size), 2.0)
+    unsharp_mask = cv2.addWeighted(img, threshold, gaussian, -1.0, 0)
+    # Clip the pixel values to the valid range [0, 255]
+    unsharp_mask = np.clip(unsharp_mask, 0, 255)
+    # Normalize the image to bring pixel values back to [0, 255]
+    cv2.normalize(unsharp_mask, unsharp_mask, 0, 255, cv2.NORM_MINMAX)
+    return unsharp_mask