拖动鼠标在opencv Python中绘制直线并获取直线端点的坐标

import cv2

# 定义全局变量
drawing = False
line_start = (-1, -1)
line_end = (-1, -1)

# 鼠标事件回调函数
def draw_line(event, x, y, flags, param):
    global drawing, line_start, line_end

    if event == cv2.EVENT_LBUTTONDOWN:
        drawing = True
        line_start = (x, y)

    elif event == cv2.EVENT_LBUTTONUP:
        drawing = False
        line_end = (x, y)
        cv2.line(img, line_start, line_end, (0, 255, 0), 2)
        cv2.imshow("image", img)

# 创建一个黑色图像窗口
img = np.zeros((512, 512, 3), np.uint8)
cv2.namedWindow("image")
cv2.setMouseCallback("image", draw_line)

while True:
    cv2.imshow("image", img)
    if cv2.waitKey(1) == ord('q'):
        break

cv2.destroyAllWindows()

# 输出直线端点的坐标
print("直线起点坐标：", line_start)
print("直线终点坐标：", line_end)