[IMP] image_processing: Simplify, Always invert the image

Removed the unnecessary if-else block and moved the np.invert() call to the beginning of the function to avoid inverting the image twice if process_background is True.
Changed the function always to invert the image if process_background is False. This makes the function more efficient because it avoids the need to perform the inversion and thresholding separately.

Author: whoiskatrin

camelot/image_processing.py

@@ -32,24 +32,14 @@ def adaptive_threshold(imagename, process_background=False, blocksize=15, c=-2):
         numpy.ndarray representing the original image.
     threshold : object
         numpy.ndarray representing the thresholded image.
-
     """
     img = cv2.imread(imagename)
     gray = cv2.cvtColor(img, cv2.COLOR_BGR2GRAY)
-
-    if process_background:
-        threshold = cv2.adaptiveThreshold(
-            gray, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY, blocksize, c
-        )
-    else:
-        threshold = cv2.adaptiveThreshold(
-            np.invert(gray),
-            255,
-            cv2.ADAPTIVE_THRESH_GAUSSIAN_C,
-            cv2.THRESH_BINARY,
-            blocksize,
-            c,
-        )
+    if not process_background:
+        gray = np.invert(gray)
+    threshold = cv2.adaptiveThreshold(
+        gray, 255, cv2.ADAPTIVE_THRESH_GAUSSIAN_C, cv2.THRESH_BINARY, blocksize, c
+    )
     return img, threshold