MATLAB: Trim RGB Matrix in MatLab

Image Processing ToolboxMATLAB C/C++ Math Librarymatlab codermatrixmatrix manipulation

I have a RGB matrix like this:
          0  0  0    0  0   0   0    0
          0  0  23   0  0   0   0    0
          0  1  255  0  0   130 22   0
          0  49 0    0  0   0   120  0
          0  0  0    0  79  0   213  0
          0  0  0    0  0   0   0    0
and I want to trim this matrix (in other words, remove zeroes at the boundaries) to be like:
          0  23   0  0   0   0  
          1  255  0  0   130 22
          49 0    0  0   0   120
          0  0    0  79  0   213
And also want to know the middle zero(in other words, longest consecutive of zeros) of every row to be like:
1st row: 4 (There are 5 zeros in the first row. But 4 zeros started at middle point and did not end.)
2nd row: 2 (There are 2 zeros in the second row.)
3rd row: 4 (There are 4 zeros in the third row.)
4th row: 3 (There are 4 zeros in the last row. But 3 zeros finished at middle point.)

Best Answer

You can do
[rows, columns] = find(m > 0);
row1 = min(rows);
row2 = max(rows);
col1 = min(columns);
col2 = max(columns);
m2 = m(row1:row2, col1:col2)
Related Question