마우스 및 트랙바 이벤트 사용¶

import numpy as np
import cv2

def onChange(value):
    global image, title

    add_value = value -int(image[0][0])
    image = image + add_value
    cv2.imshow(title, image)

def onMouse(event, x, y, flags, param):
    global image, bar_name

    if event == cv2.EVENT_RBUTTONDOWN:
        if (image[0][0] < 246):
            image = image + 10
            cv2.setTrackbarPos(bar_name, title, image[0][0])
            cv2.imshow(title, image)

    elif event == cv2.EVENT_LBUTTONDOWN:
        if (image[0][0] >=10):
            image = image - 10
            cv2.setTrackbarPos(bar_name, title, image[0][0])
            cv2.imshow(title, image)

image = np.zeros((300, 500), np.uint8) # 영상 생성
title = "Mouse & Trackbar  event"
bar_name = "Brightness"
cv2.imshow(title, image)

cv2.createTrackbar(bar_name, title, image[0][0], 255, onChange) # 트랙바 콜백
cv2.setMouseCallback(title, onMouse)
cv2.waitKey(0)
cv2.destroyAllWindows()