Opencv manually obtain the coordinates of a point in an image.

Nov 7, 202372

AI Translation

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AI-generated summary

This code is a function that allows the user to click on an image and retrieve the coordinates of the clicked points. It uses the OpenCV library to display the image and handle mouse events. The function takes an image as input, creates an empty list to store the coordinates, displays the image in a window, sets a callback function for mouse events, waits for a key press, and returns the coordinates of the clicked points.

code#

import cv2


def click_event(event, x, y, flags, param):
    if event == cv2.EVENT_LBUTTONDOWN:
        print('Mouse click at coordinates : ', x, ',', y)
        param.append((x, y))

def get_click_coordinates(image):
    # create an empty list to store the coordinates
    coordinates = []

    # display the image in a window
    cv2.imshow('image', image)

    # set the callback function for mouse events
    cv2.setMouseCallback('image', click_event, param=coordinates)

    # wait until any key is pressed
    cv2.waitKey(0)

    # return the coordinates
    return coordinates

if __name__ == "__main__":
    ############# example #############
    image = cv2.imread("test.png")
    coordinates = get_click_coordinates(image)
    print(coordinates)

explain#

Input: An image in numpy format
Process: Click to display the position of the desired points in the image
Output: Returns a list containing the coordinates of the clicked points