title: Image Registration using orb - warped image not changing
body: <p>I'm trying to register 2 similar images; however I end up with the exact reference picture after executing my code.</p>
  
  <p>My main aim from registering those 2 pictures is to find the differences, any ideas how can I obtain the difference?</p>
  
  <pre><code>orb= cv.ORB_create(1000)
  kp1, des1 = orb.detectAndCompute(grey, None)
  kp2, dess2 = orb.detectAndCompute(greyy, None)  
  matcher = cv.DescriptorMatcher_create(cv.DescriptorMatcher_BRUTEFORCE_HAMMING)
  
  matches = matcher.match(des1, des2, None)
  matches = sorted(matches, key=lambda x:x.distance)
  
  points1 = np.zeros((len(matches), 2), dtype=np.float32)
  points2 = np.zeros((len(matches), 2), dtype=np.float32)
  
  for i, match in enumerate(matches):
      points1[i, :] = kp1[match.queryIdx].pt
      points2[i, :] = kp2[match.trainIdx].pt
  
  h, mask= cv.findHomography(points1, points2, cv.RANSAC)
  
  regimg = cv.warpPerspective(img1, h, (width,height))
  cv.imshow('registered', regimg)
  </code></pre>
  
  <p>As requested in the comments: <a href="https://i.stack.imgur.com/U5qEz.jpg" rel="nofollow noreferrer">Matched images using orb  </a></p>