Table 3.

Average prediction error obtained by combination features of single image component

Image feature combination	Average prediction error
	Image component
	Full component	Red component	Green component	Blue component	Gray component
FOS + HOG	± 3.52	± 3.14	± 3.05	± 3.46	± 3.28
FOS + LBP	–	± 3.35	± 3.23	± 2.87	± 3.15
FOS + GLCM	–	± 2.81	± 2.81	± 2.81	± 2.80
FOS + Prewitt	–	± 2.89	± 2.91	± 2.94	± 2.79
HOG + LBP	–	± 3.31	± 3.38	± 3.60	± 3.55
HOG + GLCM	–	± 4.56	± 4.34	± 3.46	± 4.63
HOG + Prewitt	–	± 3.72	± 3.56	± 4.72	± 4.38
LBP + GLCM	–	± 2.80	± 2.80	± 3.06	± 2.82
LBP + Prewitt	–	± 2.94	± 2.78	± 2.84	± 2.90
GLCM + Prewitt	–	± 3.23	± 3.74	± 3.60	± 3.83