title: OpenCv Python SIFT-How to reduce the number of Keypoints?
body: <p>I am wondering if there is a way to set the max number of the keypoints extracted from each image using OpenCV Python. I would prefer to let the number of keypoints vary from image to image instead of just setting the same number of keypoints for each image. </p>
  
  <pre><code>for pic in Training:
    kp, des = cv2.SIFT().detectAndCompute(pic, None)
    descriptors = np.append(descriptors, des)
  </code></pre>