图像处理练习

制作一个滑动条调色板，使用函数cv2.getTrackbarPos()；cv2.creatTrackbar()

import cv2
import numpy as np

def nothing(x):
    pass

img = np.zeros((300,512,3), np.uint8)
cv2.namedWindow('image')

”创建一个开关“
switch = '0:OFF\n1:ON'
cv2.createTrackbar(switch,'image',0,1,nothing)

”创建3个调色条“
cv2.createTrackbar('R','image',0,255,nothing)
cv2.createTrackbar('G','image',0,255,nothing)
cv2.createTrackbar('B','image',0,255,nothing)

while(1):
    cv2.imshow('image', img)
    k=cv2.waitKey(0)
    if k == ord('q'):#按q键退出
        break

                ”从调色条 获取值“
    r = cv2.getTrackbarPos('R','image')
    g = cv2.getTrackbarPos('G','image')
    b = cv2.getTrackbarPos('B','image')

        ”开关“
    change = cv2.getTrackbarPos(switch, 'image')
    if k == ord('s') and change == 1:
        img[:]=[r,g,b]

cv2.destroyAllWindows()