import cv2


img_path = 'qingche.jpg'

bgr_img = cv2.resize(cv2.imread(img_path), (512, 512))
if bgr_img is None:
    raise ValueError(f"无法读取图像: {img_path}")
b_channel, g_channel, r_channel = cv2.split(bgr_img)

def mouse_callback(event, x, y, flags, param):
    """鼠标回调函数：点击时显示灰度值"""
    if event == cv2.EVENT_LBUTTONDOWN:
        # 获取灰度值（灰度图中直接取值）
        img = param.get('img')
        window = param.get('window')
        gray_value = img[y, x]
        # 在彩色原图的副本上显示文本
        text = f'Gray: {gray_value}'
        cv2.putText(img, text, (x, y), cv2.FONT_HERSHEY_SIMPLEX, 0.6, (0, 0, 255), 2)
        cv2.imshow(window, img)

# 创建窗口并绑定回调函数
for pic, name in [(b_channel, 'B Channel'),(g_channel, 'G Channel'),(r_channel, 'R Channel')]:
    img = pic
    window = name
    params = {
        'img':img,
        'window':window
    }
    cv2.namedWindow(window)
    cv2.setMouseCallback(window, mouse_callback, param=params)

# 显示图像并等待退出
while True:
    cv2.imshow('B Channel', b_channel)
    cv2.imshow('G Channel', g_channel)
    cv2.imshow('R Channel', r_channel)
    cv2.imshow('rgb', bgr_img)
    key = cv2.waitKey(1) & 0xFF
    if key == ord('q') or key == 27:  # 按'q'或ESC键退出
        break

cv2.destroyAllWindows()
pass