I have a color image , I want to get the relationship between the intensity and distance(we know the scale bar 1.9pixel/micro))

My input is the .mat file. I need calculate from in the center.

[QUAN WANG]

the .mat file actually is a image, if you use imagesc

[Image Analyst]

I don't understand the question. I see a bunch of circles and the center of the set of circles, but exactly what do you want to measure? The distance of WHAT from the center?

See the FAQ:

https://matlab.fandom.com/wiki/FAQ#How_can_I_fit_a_circle_to_a_set_of_XY_data.3F