title: Hi friends i just now installed opencv and checking the basic code but it results in error. The code is :
body: <pre><code>import numpy as np
  import cv2
  
  cap = cv2.VideoCapture(0)
  
  while(True):
      # Capture frame-by-frame
      ret, frame = cap.read()
  
      # Our operations on the frame come here
      gray = cv2.cvtColor('frame', cv2.COLOR_BGR2GRAY)
  
      # Display the resulting frame
      cv2.imshow('frame',frame)
      cv2.imshow('gray',gray)
      if cv2.waitKey(20) &amp; 0xFF == ord('q'):
          break
  
  # When everything done, release the capture
  cap.release()
  cv2.destroyAllWindows()`
  
  Traceback (most recent call last):
    File "C:\Users\Kouissi\Desktop\camera-test\camera_test.py", line 11, in &lt;module&gt;
      gray = cv2.cvtColor('frame', cv2.COLOR_BGR2GRAY)
  TypeError: Expected cv::UMat for argument 'src'
  </code></pre>