How to crop the circular ROI (already done) from the image ? I want to eliminate the black background for calculating average RGB values, so that i can calculate average luminance from the image.

clear all

clc

hdr=hdrread('testfile.hdr');

rgb=tonemap(hdr);

figure;

imshow(rgb)

roi = drawcircle('Center',[400 400],'Radius',398);

BW=createMask(roi);

[Omer Akatekin]

Are you doing for tunnel lighting access zone calculation ? because it seems to what i am trying to design app for these nowadays

Answer 1

[Abhishek Gupta]

Hi,

Referring to the following MATLAB Answer, which might help you in resolving the issue: -

Average pixel values of several ROIs