Issue with averaging images in matlab -

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when try average folder of jpeg matlab images, blank image. i've gone on code million times, , don't know i'm going wrong. (also know hard coded of numbers because wanted take specific folder , i've double checked million times, they're right.)

            %takes images in folder , averages values      %opens folder     function avg_image = average_images()     folder_name = uigetdir;       folder_directory = dir(folder_name);      filename = folder_directory(3).name;     len = length(folder_directory);      org_image = imread(filename);      sum_image = org_image;      %adds files      = 4:len           filename = folder_directory(i).name;       org_image = imread(filename);      sum_image = sum_image + org_image;       end     %calculates average    avg_image = sum_image/(len-2);     %saves average fits file , displays     imwrite(avg_image, 'averagefile.jpg');     read_image = imread('averagefile.jpg');    imshow(read_image)     end

the problem code reading in jpgs uint8 (default) , doing math images matrices of uint8's (0-255 integers). read in org_image, above , inside loop, cast result double:org_image = double(imread(filename)). after you're done averaging, need cast back, avg_image = uint8(sum_image/(len-2)).

when math uint8's, divisions messy since decimals truncated. 4 divided 8 when both doubles gives 0.5. when both integers, 0.


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