Table 1.

Types of handcrafted features

Histogram based image intensity	Geometry	GLCM based texture	NGTDM based texture
Minimum	Volume	Energy	Coarseness
Maximum	Major diameter	Entropy	Contrast*
Mean	Minor diameter	Correlation	Busyness
Stand deviation	Eccentricity	Contrast*	Complexity
Sum	Elongation	Texture Variance	Texture Strength
Median	Orientation	Sum-Mean
Skewness	Bounding Box Volume	Inertia
Kurtosis	Perimeter	Cluster Shade
Variance		Cluster tendency
		Homogeneity
		Max-Probability
		Inverse Variance

NOTE.

^*Contrast: Different calculation methods were employed in GLCM and NGTDM, though the same names are indicated.

Abbreviations: GLCM, Gray level co-occurrence matrix; NGTDM, Neighborhood gray tone difference matrix.