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Properties of graylevel cooccurrence matrix
stats = graycoprops(glcm, properties)
stats = graycoprops(glcm, properties) calculates the statistics specified in properties from the graylevel cooccurence matrix glcm. glcm is an mbynbyp array of valid graylevel cooccurrence matrices. If glcm is an array of GLCMs, stats is an array of statistics for each glcm.
graycoprops normalizes the graylevel cooccurrence matrix (GLCM) so that the sum of its elements is equal to 1. Each element (r,c) in the normalized GLCM is the joint probability occurrence of pixel pairs with a defined spatial relationship having gray level values r and c in the image. graycoprops uses the normalized GLCM to calculate properties.
properties can be a commaseparated list of strings, a cell array containing strings, the string 'all', or a space separated string. The property names can be abbreviated and are not case sensitive.
Property  Description  Formula 

'Contrast'  Returns a measure of the intensity contrast between a pixel and its neighbor over the whole image. Range = [0 (size(GLCM,1)1)^2] Contrast is 0 for a constant image. 

'Correlation'  Returns a measure of how correlated a pixel is to its neighbor over the whole image. Range = [1 1] Correlation is 1 or 1 for a perfectly positively or negatively correlated image. Correlation is NaN for a constant image. 

'Energy'  Returns the sum of squared elements in the GLCM. Range = [0 1] Energy is 1 for a constant image. 

'Homogeneity'  Returns a value that measures the closeness of the distribution of elements in the GLCM to the GLCM diagonal. Range = [0 1] Homogeneity is 1 for a diagonal GLCM. 

stats is a structure with fields that are specified by properties. Each field contains a 1 x p array, where p is the number of graylevel cooccurrence matrices in GLCM. For example, if GLCM is an 8 x 8 x 3 array and properties is 'Energy', then stats is a structure containing the field Energy, which contains a 1 x 3 array.
Energy is also known as uniformity, uniformity of energy, and angular second moment.
Contrast is also known as variance and inertia.
glcm can be logical or numeric, and it must contain real, nonnegative, finite, integers. stats is a structure.
GLCM = [0 1 2 3;1 1 2 3;1 0 2 0;0 0 0 3]; stats = graycoprops(GLCM) I = imread('circuit.tif'); GLCM2 = graycomatrix(I,'Offset',[2 0;0 2]); stats = graycoprops(GLCM2,{'contrast','homogeneity'})