OpenCV SurfFeatureDetector principles of working

Question

By what principle SurfFeatureDetector finds the keypoints?. In other words, what qualities should has the part of the image to be caught as a keypoint?.

Answer 1

Stackoverflow responses should be more than a link, but your question cannot be answered in less than a good, full-size scientific paper. Go directly to source:

Here you find a detailed description of the algorithm. Look for the "Notes on the OpenSURF Library" pdf.