about Finding the Fractal Dimension using Box Counting method

hello I'm highschool student studying fractal and trying to observe(?) it in animals' organ..

Can you give me some advice for generalizing the photo(of organ) and find the fractal dimension? Please,,

I have no idea how to set up RGB range and generalizing photos...

[Gang-Gyoo]

Go to 'file exchange' and search for 'Box Counting Method'