SIFT Based Vein Recognition Models: Analysis and Improvement

Table 3

Influence of CEs on the Precision-Recall/Equal Error Rate of SIFT descriptor matching. Values represent variations of the PR/EER in respect to the value of the same metric in the absence of CE.

Evaluation item	Linear/nonlinear functional enhancement (LNFE)
	IN	GLS	CS	GC08	LS	UM	HBF	HF	INE
PR	−2.88	−9.16	−2.46	−1.98	−2.41	−11.76	−3.29	−1.21	−1.07
EER	−0.94	−2.11	−0.70	−0.52	−0.82	−2.25	−1.12	−0.52	−0.34
Evaluation item	HE and its variants (HEs)				Hierarchical enhancement models (HEM)
	HE	AHE	CLAHE	CLHE	IHE	DHE	RASF	HHE	HEHBF
PR	−8.77	−23.36	−8.69	−8.11	−15.07	−37.29	−10.93	−18.59	−9.19
EER	−1.98	−5.14	−2.05	−1.91	−6.20	−7.97	−2.53	−6.95	−2.39