How to analyze fraction of an image based on brightness?

I have a series of images and we are want to anazlyze their brightness. Basically, how should I proceed with setting a threshold brightness value and then be able to calcalate the % above and below this brightness threshold.

Answer 1

[Sulaymon Eshkabilov]

The brighness can be computed as shown here :

https://www.mathworks.com/matlabcentral/answers/48841-how-to-find-the-brightness-of-an-image

If there is a series of images with ordered names (e.g.: img1.png, img2.png, ....) , then you'd need to use [for .. end] loop, e.g.:

Name='img';
Ext = '.png';
for ii=1:n_images
    Name_IMG=strcat(Name, num2str(ii), Ext);
    AA = imread(Name_IMG);
    ... % use the commands given in the above link
end