I am working with OpenCV keypoints and I got a questions about keyPoint size and octave.
I know that a keyPoint have a coordinate (x,y) and size which simply can be described as a circle with (x,y) center and radius of size.
And I know that there are some octave levels (during which the image is being downsampled by 2) that the keyPoints are being detected.
I have 2 questions about this.
- Is there a some relationship between the keypoint size and the octave or sublevel when it is detected?
- What is the maximum number of octave levels that image can have? As at every octave level the image is being downsampled by 2 does that mean that the answer is Log(2,image_size)? And what about sublevel ?