OpenCV 3.x with Python By Example - Second Edition

Mouse inputs

In this section, we will see how to use the mouse to interact with the display window. Let's start with something simple. We will write a program that will detect the quadrant in which the mouse click was detected. Once we detect it, we will highlight that quadrant:

import cv2 import numpy as np def detect_quadrant(event, x, y, flags, param): if event == cv2.EVENT_LBUTTONDOWN: if x > width/2: if y > height/2: point_top_left = (int(width/2), int(height/2)) point_bottom_right = (width-1, height-1) else: point_top_left = (int(width/2), 0) point_bottom_right = (width-1, int(height/2)) else: if y > height/2: point_top_left = (0, int(height/2)) point_bottom_right = (int(width/2), height-1) else: point_top_left = (0, 0) point_bottom_right ...