message: changed no longer patented SIFT
diff: @@ -36,7 +36,7 @@ except (AttributeError, cv.error) as e:
  # if SURF not available, ORB is default
  FEATURES_FIND_CHOICES['orb'] = cv.ORB.create
  try:
  - FEATURES_FIND_CHOICES['sift'] = cv.xfeatures2d_SIFT.create
  + FEATURES_FIND_CHOICES['sift'] = cv.SIFT_create
  except AttributeError:
  print("SIFT not available")
  try:
  