How to identify contour which are not directly separated from each other?

Question

Please can some one explain how to identify square shape of contours which are not exactly separated each other. For example I need to identify the number of squares in below image and the x,y coordinates of their edges. I try to go through this question but it didn't work for me.

So please can some one explain this using simple code example.

This is the image that I can generated can you please explain how to identify above squares in this image.

So please be kind enough to explain this.

Answer 1

You have to use fact, that red component of each square equals 255, and do the threshold. Here's what I've done:

1. Do a red color segmentation:

2. Do dilatation (to remove holes):

3. (Optional) Do a check if each contour is a square.

Code:

Mat src = imread("input.png"), red;
extractChannel(src, red, 2);

threshold(red, red, 254, 255, THRESH_BINARY);

Mat element = getStructuringElement(MORPH_RECT, Size( 2, 2 ), Point( 1, 1 ));
dilate(red, red, element);