Didn't I answer that in your duplicate question? https://www.mathworks.com/matlabcentral/answers/1938859-how-to-save-all-the-images-data-in-workplace-after-processing-all-the-images#answer_1206859
You have to get the values and index them, for example:
% Specify the folder where the files live.
myFolder = pwd;
% Get a list of all files in the folder with the desired file name pattern.
filePattern = fullfile(myFolder, '*.bmp'); % Change to whatever pattern you need.
theFiles = dir(filePattern);
allAreas = []; % Array to store all the areas from all the images.
allMeans = [];
for k = 1 : length(theFiles)
baseFileName = theFiles(k).name;
fullFileName = fullfile(theFiles(k).folder, baseFileName);
fprintf(1, 'Now reading %s\n', fullFileName);
% Read in grayscale image
grayImage = imread(fullFileName);
% Threshold image
mask = imbinarize(grayImage);
% Compute areas for k'th image
props = regionprops(mask);
% Get all areas.
theseAreas = [props.Area]; % Areas of blobs in only this particular image.
% Append to our growing list of areas for all images.
allAreas = [allAreas, theseAreas];
% Get the mean for this image.
allMeans(k) = mean(thisImage, 'all');
end
% Show histogram of all the areas for all the images.
figure;
subplot(1, 2, 1);
histogram(allAreas);
title('Area Histogram')
grid on;
% Show histogram of all the means for all the images.
subplot(1, 2, 2);
histogram(allMeans);
title('Mean Gray Level Histogram')
grid on;
It's a generic, general purpose demo of how to threshold an image to find blobs, and then measure things about the blobs, and extract certain blobs based on their areas or diameters.
