OpenCV Python laser dot tracking extracting x and y coordinates and store it to different variables

Question

enter image description hereI have a code here that tracks a laser dot.What I want is to get the x and y coordinates of the laser dot and store it to separate variables. Here is the code:

import cv2
import numpy as np

cap = cv2.VideoCapture(0)

while (1):

    # Take each frame
    ret, frame = cap.read()
    hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2HSV)

    lower_red = np.array([0, 0, 255])
    upper_red = np.array([255, 255, 255])
    mask = cv2.inRange(hsv, lower_red, upper_red)
    cv2.imshow('mask', mask)
    cv2.imshow('Track Laser', frame)
    if cv2.waitKey(1) & 0xFF == ord('q'):
        break

cap.release()
cv2.destroyAllWindows()

Can you show us an image? (Input/output) It's hard to do image processing without one. :) — Mateen Ulhaq, May 24 '18 at 03:26

score 1 · Answer 1 · answered May 24 '18 at 04:23

1

For multiple points or noisier data, you might want to consider clustering algorithms.

However, the image you attached is quite clear. All you need to do is find the center of it. That corresponds the the first geometrical moment (aka mean):

moments = cv2.moments(hsv[:, :, 2])
x = int(moments['m10'] / moments['m00'])
y = int(moments['m01'] / moments['m00'])

This lets us find the center fairly accurately, provided there are no outliers (e.g. noise or other circles) affecting the distribution.

Perhaps a more robust method (to noise and number of circles) would make use of Hough circles.

answered May 24 '18 at 04:23

Mateen Ulhaq

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Thank you Sir. It looks like a circle because it's near from the webcam. I doubt if it will still look like a circle from a far. But still, Thank you. – jomsamago May 24 '18 at 04:48
can i talk to you privately? – jomsamago May 31 '18 at 09:14

OpenCV Python laser dot tracking extracting x and y coordinates and store it to different variables

1 Answers1