title: Visualizing OpenCV KeyPoints
body: <p>I am learning OpenCV and at the moment I am trying to understand the underlying data stored in a <code>KeyPoint</code> so that I can better utilize that data for an application I'm working on.</p>
  
  <p>So far I have been going through these two pages:</p>
  
  <p><a href="http://docs.opencv.org/modules/features2d/doc/common_interfaces_of_feature_detectors.html?highlight=featuredetector#FeatureDetector" rel="noreferrer">http://docs.opencv.org/modules/features2d/doc/common_interfaces_of_feature_detectors.html?highlight=featuredetector#FeatureDetector</a></p>
  
  <p><a href="http://docs.opencv.org/doc/tutorials/features2d/feature_detection/feature_detection.html" rel="noreferrer">http://docs.opencv.org/doc/tutorials/features2d/feature_detection/feature_detection.html</a></p>
  
  <p>When I follow the tutorial, however, using <code>drawKeypoints()</code>, the points are all the same size and shape, and are drawn with a seemingly arbitrary color.</p>
  
  <p>I guess I could iterate through the attributes for each key point: draw a circle, draw an arrow (for the angle), give it a color based on the response, etc. But I figured there had to be a better way.</p>
  
  <p>Is there a built-in method or other approach similar to <code>drawKeypoints()</code> that will help me more efficiently visualize the <code>KeyPoints</code> of an image? </p>