Connect lines of binary image

Dear comunity,

I have the following image composed by many (almost closed) lines. I am contacting you because I would like to know if somebody has an elegant solution to connect the lines (some of them are broken). If possible, I would like to avoid the use of morphological operators as it is importat to me to maintain the lines profile.

Thank you in advance for your help,

Santiago

[KALYAN ACHARJYA]

I would like to know if somebody has an elegant solution to close the lines

What does it mean?

[Santi]

Dear Kalyan, I just changed the text so it can be better understood; I want to connect the lines. Thanks!

[Rik]

Have you tried a morphological operation with a non-symmetrical structuring element? That would probably get you most of the way there.

[Mohammad Sami]

Have you tried houghtransform. It can help you find the lines.

[H,T,R] = hough(BW);

P = houghpeaks(H,5,'threshold',ceil(0.3*max(H(:))));

lines = houghlines(BW,T,R,P,'FillGap',5,'MinLength',7);

[Santi]

Dear Mohammad Sami,

That sounds very interesting. Could you please explain a little bit more? (e.g. how to plot the lines...)

Thank you very much.

[Rik]

Have you looked at the documentation for the houghlines function? It includes an example.

As for my suggestion, you can very easily create a non-symmetrical structuring element like this:

r=1;
x=linspace(-1,1,10);
y=linspace(-2,2,10);
[X,Y]=ndgrid(x,y);
SE=sqrt(X.^2+Y.^2) <= r;