Table 3. Formulas for texture features.

Feature	Formula
Contrast	∑ i = 1 N ∑ j = 1 N ( i − j ) 2 P i . j
Correlation	∑ i = 1 N ∑ j = 1 N ( i , j ) ( P i , j − μ i μ j ) σ x σ y
Energy	∑ i = 1 N ∑ j = 1 N P i . j 2
Entropy	− ∑ i = 1 N ∑ j = 1 N P i , j * L o g b P i , j
Homogeneity	∑ i = 1 N ∑ j = 1 N P i , j 1 + ( i − j ) 2