%% Read and binarize the image
I=imread('https://i.stack.imgur.com/pRkiY.jpg');
I=rgb2gray(I);
I=I>graythresh(I)*255;
%% Get skeleton, i.e. the lines!
sk=bwmorph(~I,'skel',Inf);
%% lines are too thin, dilate them
dilated=~imdilate(sk, strel('disk', 2, 4));
%% label the image!
test=bwlabel(dilated,8);
imshow(test,[]); colormap(plasma); % use colormap parula if you prefer.
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