Table 3.

The computing times of the feature matching algorithms, of the SIFT detector, of the selection of SIFT plus ARCore feature points and of the PnP algorithm. The number of SIFT key-points, the number of SIFT plus ARCore points and the final number of matched feature points used in the PnP algorithm, are also provided.

Entry	Feature Matching Method	SIFT Time (ms)	SIFT Key Points	SIFT + ARCore Time (ms)	SIFT + ARCore Points	Feature Matching Time (ms)	Number of Matched Points	PnP Time (ms)
1	FLANN	520.47	373	631.17	287	29.51	35	2.13
	BFMatcher					174.47	19	3.65
	BFMatcher + filter					237.07	19	0.85
2	FLANN	646.52	728	614.92	340	35.6	76	2.71
	BFMatcher					289.1	20	2.14
	BFMatcher + filter					531.11	20	0.92
3	FLANN	646.81	751	727.81	438	39	89	3.04
	BFMatcher					296.99	20	2.17
	BFMatcher + filter					588.48	20	9.01
4	FLANN	500	393	835.2	274	30.25	70	1.52
	BFMatcher					100.52	20	2.1
	BFMatcher + filter					208.15	20	0.97
5	FLANN	565.36	390	573.11	214	28.01	60	1.52
	BFMatcher					104.73	20	1.98
	BFMatcher + filter					147.52	20	0.88
6	FLANN	631.42	675	628.43	232	40	58	13.8
	BFMatcher					374.5	20	1.02
	BFMatcher + filter					197.75	20	2.02
7	FLANN	462.46	275	514.04	122	19.12	22	2.61
	BFMatcher					97.2	19	1.01
	BFMatcher + filter					27.47	19	2.53
8	FLANN	504.2	403	624.71	230	17.28	55	2.53
	BFMatcher					149.51	20	0.97
	BFMatcher + filter					77.48	20	2.24
9	FLANN	481.82	328	617.19	272	19.34	46	2.23
	BFMatcher					177.72	20	1.19
	BFMatcher + filter					92.73	20	2.43
10	FLANN	493.99	343	572.32	168	25.47	44	1.2
	BFMatcher					104.86	20	0.93
	BFMatcher + filter					69.03	20	2.06
	FLANN	545.305	466	633.89	258	28.358	56	3.329
μ	BFMatcher					186.96	20	1.716
	BFMatcher + filter					217.679	20	2.391