计算用户正在查看的屏幕上的位置

Question

无论如何找到学生在屏幕上看的地方 最好使用openCV，Python，你能帮我吗？ 这就是我为检测学生所做的工作：

import cv2
import numpy as np

cap = cv2.VideoCapture(0)

while(1):

   _, frame = cap.read() 


   hsv = cv2.cvtColor(frame, cv2.COLOR_BGR2GRAY)

   circles = cv2.HoughCircles(hsv, cv2.cv.CV_HOUGH_GRADIENT, 3, 900)

   # ensure at least some circles were found
   if circles is not None:
       # convert the (x, y) coordinates and radius of the circles to integers
       circles = np.round(circles[0, :]).astype("int")

       # loop over the (x, y) coordinates and radius of the circles
       for (x, y, r) in circles:
           # draw the circle in the output image, then draw a rectangle
           # corresponding to the center of the circle
           cv2.circle(frame, (x, y), r, (0, 255, 0), 4)
           cv2.rectangle(frame, (x - 5, y - 5), (x + 5, y + 5), (0, 128, 255), -1)
   edges = cv2.Canny(hsv,100,100)
   cv2.imshow('Edges',edges)
   cv2.imshow('Original',frame)  

   k = cv2.waitKey(5) & 0xFF
   if k == 27:
       break

cv2.destroyAllWindows()
cap.release()