What exactly are the keypoint.response and keypoint.size field of a keypoint (in my case, BRISK)?
I found an answer for SURF, but I would like to know what is the meaning for binary keypoint such as BRISK (which is based on AGAST if I remember correctly).
As a reminder, here is the definition that is shown by IntelliSense when typing:
Size: diameter of the meaningful keypoint neighborhood; Response: the response by which the most strong keypoints have been selected. Can be used for further sorting or subsampling
Knowing that, I would be able to assess their use as a way to filter the keypoints.