Table 12. Time comparison for RSSCN7 image dataset.

K denotes the size of visual vocabulary.

K	Training Time				Testing Time
	Rect	Tri	Cir	HGSIR	Rect	Tri	Cir	HGSIR
50	344.01	341.116	365.354	675.43	273.08	268.44	266.62	805.59
100	502.17	520.78	543.98	1015.494	282.622	277.235	274.615	829.43
200	854.443	911.43	885.903	1784.479	291.01	281.05	278.93	838.66
400	1960.07	2085.336	1987.959	4349.514	301.06	301.25	296.27	902.55
600	4056.7	3201.738	4783.744	7351.356	430.33	334.65	327.011	1001.02