Python mouse clicks the picture in real time to output the coordinates of pixel points with OpenCV

python Click the mouse to output the coordinates of pixels in real time With the help of opencv

import cv2
img = cv2.imread("./edge1.png") # Read the picture 
a = []
b = []
def on_EVENT_LBUTTONDOWN(event, x, y, flags, param):
if event == cv2.EVENT_LBUTTONDOWN:
a.append(x)
b.append(y)
cv2.circle(img, (x, y), 3, (255, 0, 0), thickness=-1)
cv2.imshow("image", img)
print("[{},{}]".format(a[-1], b[-1])) # Output the coordinates of the last click 
cv2.namedWindow("image")
cv2.setMouseCallback("image", on_EVENT_LBUTTONDOWN)
cv2.imshow("image", img)
cv2.waitKey(0)
cv2.destroyAllWindows()

design sketch 1 as follows ：

There is still room for revision , I modified it in passing
Make it directly mark the coordinates in the picture
The code is as follows ：

import cv2
img = cv2.imread("./edge1.png") # Path to picture 
a = []
b = []
def on_EVENT_LBUTTONDOWN(event, x, y, flags, param):
if event == cv2.EVENT_LBUTTONDOWN:
xy = "[%d,%d]" % (x, y)
a.append(x)
b.append(y)
cv2.circle(img, (x, y), 3, (255, 0, 0), thickness=-1)
cv2.putText(img, xy, (x, y), cv2.FONT_HERSHEY_PLAIN,
1.0, (107, 73, 251), thickness=1) # If you do not want to display the coordinates on the picture, you can annotate the line 
cv2.imshow("image", img)
print("[{},{}]".format(a[-1], b[-1])) # Output coordinates in the terminal 
cv2.namedWindow("image")
cv2.setMouseCallback("image", on_EVENT_LBUTTONDOWN)
cv2.imshow("image", img)
cv2.waitKey(0)
cv2.destroyAllWindows()

design sketch 2 as follows ：

Reference resources here.