kevinlinxc · March 15, 2024 00:33 · Mar 15, 2024
diff --git a/opencv_trackbars_example.py b/opencv_trackbars_example.py
@@ -0,0 +1,37 @@
+import cv2
+import numpy as np
+
+
+def nothing(x):
+    pass
+
+
+# Create a black image, a window
+img = np.zeros((300, 512, 3), np.uint8)
+cv2.namedWindow("image")
+
+# create trackbars for color change
+cv2.createTrackbar("R", "image", 0, 255, nothing)
+cv2.createTrackbar("G", "image", 0, 255, nothing)
+cv2.createTrackbar("B", "image", 0, 255, nothing)
+
+# create switch for ON/OFF functionality
+switch = "0 : OFF \n1 : ON"
+cv2.createTrackbar(switch, "image", 0, 1, nothing)
+
+while 1:
+    cv2.imshow("image", img)
+    k = cv2.waitKey(1) & 0xFF
+    if k == 27:
+        break
+    # get current positions of four trackbars
+    r = cv2.getTrackbarPos("R", "image")
+    g = cv2.getTrackbarPos("G", "image")
+    b = cv2.getTrackbarPos("B", "image")
+    s = cv2.getTrackbarPos(switch, "image")
+    if s == 0:
+        img[:] = 0
+    else:
+        img[:] = [b, g, r]
+
+cv2.destroyAllWindows()