diff --git a/ar_tag_pose_aruco_board.py b/ar_tag_pose_aruco_board.py
index 83ae10b..fe252db 100644
--- a/ar_tag_pose_aruco_board.py
+++ b/ar_tag_pose_aruco_board.py
@@ -1,9 +1,7 @@
-from PIL.ImageOps import posterize
-
+import cv2 as cv
+import numpy as np
 from ar_tag_pose import ArTagPose
 from aruco_types import ARUCO_DICT
-import numpy as np
-import cv2 as cv
 
 def factory(dict_type: int, board_size: cv.typing.Size, marker_length: float=100.0, marker_sep=10, margins=10):
 	aruco_dict = cv.aruco.getPredefinedDictionary(dict_type)
diff --git a/ar_tag_pose_charuco_board.py b/ar_tag_pose_charuco_board.py
index cb24029..148bc50 100644
--- a/ar_tag_pose_charuco_board.py
+++ b/ar_tag_pose_charuco_board.py
@@ -1,9 +1,7 @@
-from PIL.ImageOps import posterize
-
+import cv2 as cv
+import numpy as np
 from ar_tag_pose import ArTagPose
 from aruco_types import ARUCO_DICT
-import numpy as np
-import cv2 as cv
 
 def factory(dict_type: int, board_size: cv.typing.Size, square_length: float = 5.0, marker_length: float = 3.0,	margin_length=0):
 	im_w = 800