A=[2 4 1 2 ;2 1 2 4; 2 3 1 2 ;1 3 3 2] [glcm,SI] = graycomatrix(A,'NumLevels',9,'G',[]);
%The values in SI are between 1 and NumLevels. %'numlevels'=Integer specifying the number of gray-levels to use when scaling the grayscale values in I. For example, if NumLevels is 8, graycomatrix scales the values in I so they are integers between 1 and 8. The number of gray-levels determines the size of the gray-level co-occurrence matrix (glcm). By default-8 (numeric),2 (binary)
