How to compute regions of matrix Let's say we have the following matrix:

0 0 0 0 0 0
0 1 0 0 0 0
1 1 0 0 0 0
1 1 0 0 0 0
0 0 0 0 0 0
0 0 0 1 1 1
0 0 0 0 1 1
0 0 0 0 0 0


I want to calculate the size of every connected region of 1s and also get the corresponding matrix elements of each region. The size should be computed as (width + heigth) / 2.

In the example the bottom left region would have size (2 + 3) / 2 and the bottom right region would have size (3 + 2) / 2.

Additional to the size of the regions I also want the corresponding entries of the regions, i.e. region 1 has entries (2,2), (3,1), (3,2) and so on.

How can this be done in Matlab?

I'm looking forward for the answers and wish everybody all the best.
Lets take the given matrix as 
$$A=\left[\begin{array}{cccccc}&amp;0 &amp;0 &amp;0 &amp;0 &amp;0 &amp;0 &amp;\\
&amp;0 &amp;\color{red}{1} &amp;0 &amp;0 &amp;0 &amp;0 \\
&amp;\color{red}{1} &amp;\color{red}{1} &amp;0 &amp;0 &amp;0 &amp;0 \\
&amp;\color{red}{1} &amp;\color{red}{1} &amp;0 &amp;0 &amp;0 &amp;0 \\
&amp;0 &amp;0 &amp;0 &amp;0 &amp;0 &amp;0 \\
&amp;0 &amp;0 &amp;0 &amp;\color{blue}{1} &amp;\color{blue}{1} &amp;\color{blue}{1} \\
&amp;0 &amp;0 &amp;0 &amp;0 &amp;\color{blue}{1} &amp;\color{blue}{1} \\
&amp;0 &amp;0 &amp;0 &amp;0 &amp;0 &amp;0\end{array}\right]$$

Then use the MATLAB function bwlabel to find the connected components in the matrix.

cc=bwlabel(A);


when you run this in MATLAB you will get cc as,

$$ cc = \left[\begin{array}{cccccc} 
  &amp;0&amp;      0&amp;      0&amp;      0&amp;      0&amp;      0&amp; \\
     &amp;0&amp;      \color{red}{1}&amp;      0&amp;      0&amp;      0&amp;      0&amp; \\
     &amp;\color{red}{1}&amp;      \color{red}{1}&amp;      0&amp;      0&amp;      0&amp;      0&amp; \\
     &amp;\color{red}{1}&amp;      \color{red}{1}&amp;      0&amp;      0&amp;      0&amp;      0&amp; \\
     &amp;0&amp;      0&amp;      0&amp;      0&amp;      0&amp;      0&amp; \\
     &amp;0&amp;      0&amp;      0&amp;      \color{blue}{2}&amp;      \color{blue}{2}&amp;      \color{blue}{2}&amp; \\
     &amp;0&amp;      0&amp;      0&amp;      0&amp;      \color{blue}{2}&amp;      \color{blue}{2}&amp; \\
     &amp;0&amp;      0&amp;      0&amp;      0&amp;      0&amp;      0&amp; \end{array}\right]$$

1 indicate connected region 1, 2 indicates connected region 2, etc

If you want 2D pixel locations use, find function in cc

i.e.:

[r c]=find(cc==1) gives the row (r) and column (c) locations of the 1st connected region.

[r c]=find(cc==2) gives the row (r) and column (c) locations of the 2nd connected region, and so on.

Now you can get what ever you want..