Python OpenCV学习笔记之：处理滚动条事件

# -*- coding: utf-8 -*-
# 处理滚动条事件

import cv2 as cv
import numpy as np

def on_trace_bar_changed(args):
pass

img = np.zeros((512,512,3),np.uint8)

cv.namedWindow("image")

# 创建滚动条
cv.createTrackbar("R","image",0,255,on_trace_bar_changed)
cv.createTrackbar("G","image",0,255,on_trace_bar_changed)
cv.createTrackbar("B","image",0,255,on_trace_bar_changed)

while True:
cv.imshow("image",img)
k = cv.waitKey(10) & 0xFF
if k == 27:
break
# 获取滚动条的值
r = cv.getTrackbarPos("R","image")
g = cv.getTrackbarPos("G","image")
b = cv.getTrackbarPos("B","image")

img[:] = [b,g,r]