Added matlab binarization file

binarization/binarizer.m

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+function out_im = binarizer(in_im, v, h)
+
+%This programs splits an image into 'v' blocks in vertical direction
+% and into 'h' blocks in horizontal direction. All the bloacks are equal.
+
+[x, y] = size(in_im); %size of the input image
+out_im = []; %output image
+
+for ii = 1:(v)
+    temp = [];
+    ranx = ((ii-1)*ceil(x/v)+1):(ii*ceil(x/v)); %horizontal range
+    if ii == v
+        ranx = (((ii-1)*ceil(x/v)+1):x);
+    end
+    for jj = 1:(h)
+        rany = ((jj-1)*ceil(y/h)+1):(jj*ceil(y/h)); %horizontal range
+        if jj == h
+            rany = (((jj-1)*ceil(y/h)+1):y);
+        end
+        t = graythresh(in_im(ranx,rany));
+        temp = cat(2,temp,imbinarize(in_im(ranx,rany),t));
+    end
+    out_im = cat(1,out_im,temp);
+end
+
+end

binarization/main.m

@@ -0,0 +1,82 @@
+clear
+close all
+clc
+format compact
+
+%Loading 1st image
+im = imread('rice.tif');
+t = graythresh(im); %threshold for binarize
+
+[m, n] = imhist(im); %we need 'm' for threshold marker on the histogram
+
+figure
+subplot(1,2,1); imshow(im)
+title('Original image')
+subplot(1,2,2); imhist(im)
+line([round(255*t), round(255*t)], [0, max(m)], 'Color', 'r', 'LineWidth', 1) %threshold marker
+title({'Image histogram', ['Red line - threshold (', num2str(t * 255, 3),')']})
+
+%binarizing image
+im_bin = imbinarize(im, t);
+figure
+subplot(1,2,1); imshow(im_bin)
+title('Whole image binarization')
+
+%amount of blocks
+vert = 1; %vertical amount
+hor = 10; %horizontal amount
+
+%binarizing using blocks
+im_bin_block = binarizer(im, vert, hor);
+subplot(1,2,2); imshow(im_bin_block)
+title({['Block binarization: '], [num2str(vert),' x ',num2str(hor),' blocks']})
+
+%loading 2nd image
+
+%amount of blocks
+vert = 10; %vertical amount
+hor = 1; %horizontal amount
+
+im2 = imread('figure.png');
+t = graythresh(im2); %threshold for binarize
+im2_bin = imbinarize(im2, t);
+im2_bin_block = binarizer(im2, vert, hor);
+
+[m, ~] = imhist(im2); %we need 'm' for threshold marker on the histogram
+
+figure
+subplot(1,2,1); imshow(im2)
+title('Original image')
+subplot(1,2,2); imhist(im2)
+line([round(255*t), round(255*t)], [0, max(m)], 'Color', 'r', 'LineWidth',...
+1)
+title({'Image histogram', ['Red line - threshold (',num2str(t*255, 3),')']})
+
+figure
+subplot(1,2,1); imshow(im2_bin)
+title('Whole image binarization')
+subplot(1,2,2); imshow(im2_bin_block)
+title({['Block binarization: '],[num2str(vert),' x ',num2str(hor),' blocks']})
+
+%trying to increase contrast
+im3 = imadjust(im2,[],[],0.5);
+t = graythresh(im3); %threshold for binarize
+im3_bin = imbinarize(im3, t);
+im3_bin_block = binarizer(im3, 10, 10);
+
+[m,n] = imhist(im3); %we need 'm' for threshold marker on the histogram
+
+figure
+subplot(1,2,1); imshow(im3)
+title('Increased contrast')
+subplot(1,2,2); imhist(im3)
+line([round(255*t), round(255*t)], [0, max(m)], 'Color', 'r', 'LineWidth',...
+1)
+title({'Image histogram', ['Red line - threshold (', num2str(round(255*t)),')']})
+
+figure
+subplot(1,2,1); imshow(im3_bin)
+title('Whole image binarization')
+subplot(1,2,2); imshow(im3_bin_block)
+title({['Block binarization: '],[num2str(vert),' x ',num2str(hor),' blocks']})
+