Image processing GLCM gray level cooccurance matrix

In function graycomatrix,the output is always 8x8 matrix,i am not getting why its 8x8 ,can anybody help me out

[aliah aljohani]

hi when i use this code I = imread('circuit.tif'); glcm = graycomatrix(I,'Offset',[2 0])

i get this error Error in graycomatrix (line 167) [I, Offset, NL, GL, makeSymmetric] = ParseInputs(varargin{:});

Error in Untitled56 (line 2) GLCM = graycomatrix(I,'Offset',[2 0;0 2]); can help me and thank you

Answer 1

[Youssef Khmou]

hi,

We already discussed that topic , so as to avoid redundancy take a quick look at this topic you will find the answer : http://www.mathworks.com/matlabcentral/answers/64179-what-is-meant-by-glcm-mean-average

Answer 2

[Teja Muppirala]

It's just the default setting. You can change the size by using the 'NumLevels' parameter.

For example,

I = imread('pout.tif');
G = graycomatrix(I,'NumLevels', 64);
imagesc(G)

See the help:

>> help graycomatrix

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    'NumLevels'      An 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).

                     'NumLevels' must be an integer. 'NumLevels' must be 2
                     if I is logical.

                     Default: 8 for numeric
                              2 for logical

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