Feature classes*	No. of features before filter	No. of features after filter
First order intensity	18	0
Shape	12	2
GLSZM	14	0
GLRLM	16	0
GLDM	14	0
GLCM	21	0
Log-sigma	419	25
Wavelet	610	12
Logarithm	47	13
Square	71	0
Square-root	71	1
Gradient	82	1
Exponential	80	5

GLDM, gray-level dependence matrix; GLSZM, gray-level size zone matrix; GLRLM, gray-level run length matrix; GLDZM, gray-level distance zone matrix; GLCM, gray-level co-occurrence matrix;

^*compactness1, compactness2, SphericalDisproportion, SumAverage, Homogeneity1 and Homogeneity2 were excluded for directly correlated with other feature.