rgb_trackbar.py

# -*- coding: utf-8 -*-
"""
Created on Thu May 21 18:14:45 2020

@author: atakan
"""

import numpy as np
import cv2 as cv

def nothing(x):
    print(x)

# Create a black image, a window
img = np.zeros((300,512,3), np.uint8)
cv.namedWindow('image')

cv.createTrackbar('B', 'image', 0, 255, nothing)
cv.createTrackbar('G', 'image', 0, 255, nothing)
cv.createTrackbar('R', 'image', 0, 255, nothing)

switch = '0 : OFF\n 1 : ON'
cv.createTrackbar(switch, 'image', 0, 1, nothing)

while(1):
    cv.imshow('image',img)
    k = cv.waitKey(1) & 0xFF
    if k == 27:
        break

    b = cv.getTrackbarPos('B', 'image')
    g = cv.getTrackbarPos('G', 'image')
    r = cv.getTrackbarPos('R', 'image')
    s = cv.getTrackbarPos(switch, 'image')

    if s == 0:
       img[:] = 0
    else:
       img[:] = [b, g, r]
    if cv.waitKey(1) & 0xFF == ord('q') :
       break



cv.destroyAllWindows()