How can I compare whole set of binary images

Hey people,

I need a help, because I don't know how to extricate myself from a code. My code has to compare two binary images. Image 1 has just some pixels with value 0 and that is also case for Image 2. So, task of my code is to compare if those pixels are overlapped, and if so, overlapped pixels on Image 2 would get a value 1. It has do a recursion for a set of binary images.

I've already done something, but manually.

Example:

Image 1 <http://img600.imageshack.us/img600/4932/image1si.jpg>

Image 2 <http://img849.imageshack.us/img849/2171/image2oyp.jpg>

Image 2 after comparison <http://img856.imageshack.us/img856/9759/image2aftercomparison.jpg>

I give you my unfinished code, but there are some written comments what it needs to do at those lines.

myFolderInput = 'F:\input_with_flakes\';

myFolderOutput= 'F:\output_wihout_flakes\';

    if ~isdir(myFolderInput)
      errorMessage = sprintf('Error: The following folder does not exist:\n%s', myFolderInput);
      uiwait(warndlg(errorMessage));
      return;
    end

    if ~isdir(myFolderOutput)
      errorMessage = sprintf('Error: The following folder does not exist:\n%s', myFolderOutput);
      uiwait(warndlg(errorMessage));
      return;
    end

    filePattern = fullfile(myFolderInput, '*.jpg');

    jpegFiles = dir(filePattern);

    for k = 1:length(jpegFiles)

      baseFileName = jpegFiles(k).name;
      fullFileName = fullfile(myFolderInput, baseFileName);
      fprintf(1, 'Now reading %s\n', fullFileName);
      imageArray = imread(fullFileName);

      [i j]=size(imageArray)

      if k==1
          fprintf('The first one is skipped\n')
      else
          for m=1:i
            for n=1:j
                if imageArray(m,n)==imageArray(m,n)  % if Previous Image(m,n)==Current Image(m,n)
                   imageArray(m,n)=1;                % Current Image(m,n)=1;
                elseif imageArray(m,n)==0            % elseif Current Image(m,n)==0
                   imageArray(m,n)=0;                % Current Image(m,n)=0;
                end
            end
          end
      end

      filename = sprintf('Excluded_%s', baseFileName);
      imwrite(imageArray,[myFolderOutput, filename],'jpeg');

    end

Answer 1

[Christian Lenz]

Would it be possible to use a simpler code?

 imgOverlap_pos = img1 .* img2;

This is pixel-wise multiplication. It can be 0*0=0, 0*1=0, 1*0=0, 1*1=0. So your resulting image shows ones in the places where the two images overlap. Then do the same with the negative images.

 imgOverlap_neg = imcomplement(img1) .* imcomplement(img2);

And your result would be:

 imgOverlap = imgOverlap_pos + imgOverlap_neg;

Around that you'll then need one loop to go through all your images.