centroid distance calculation at 10 degree?

I m having leaf image I need to calculate 36 centroid contour descriptor of it @ distance of 10 degree starting from maximum radius. I have used flavia dataset and have to calculate for its image but here I have attached one image. I got the centroid, centroid distance from centroid to every boundary pixel and max of it also. kindly guide me how can I proceed further. plz help

Thanx