[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.

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