TABLE 2. Comparison of Results Between EFGM (Linear Bases) and Linear Triangular Finite Element Approach. Each Data Cell Represents Mean and Standard Deviation of the Position Differences Between the Ground Truth and Corresponding Algorithms. The Total Mean and Standard Deviation for Each Algorithm are Calculated Using All the Nodal Differences of the Sixteen Frames. EFGM: Total Mean: 0.1189, Total s.d.: 0.0672. FEM: Total Mean: 0.1793, Total s.d.: 0.1166.

EFGM(frame#1 – 4)	0.0987 ± 0.0565	0.1097 ± 0.0589	0.0971 ± 0.0591	0.1291 ± 0.0478
EFGM(frame#5 – 8)	0.0704 ± 0.0696	0.1478 ± 0.0599	0.1201 ± 0.0500	0.0689 ± 0.0212
EFGM(frame#9 – 12)	0.1097 ± 0.0705	0.1511 ± 0.0562	0.0679 ± 0.0502	0.1616 ± 0.0571
EFGM(frame#13 – 16)	0.1198 ± 0.0501	0.1493 ± 0.0671	0.1267 ± 0.0605	0.1109 ± 0.0876
FEM(frame#1 – 4)	0.0218 ± 0.0598	0.1043 ± 0.0611	0.1074 ± 0.0634	0.1308 ± 0.0581
FEM(frame#5 – 8)	0.1032 ± 0.0701	0.1871 ± 0.0901	0.2299 ± 0.0898	0.2693 ± 0.1096
FEM(frame#9 – 12)	0.3987 ± 0.1075	0.2016 ± 0.0918	0.2749 ± 0.0960	0.1712 ± 0.0801
FEM(frame#13 – 16)	0.1506 ± 0.1018	0.2018 ± 0.1231	0.1305 ± 0.0923	0.1105 ± 0.0992