SIFT Based Vein Recognition Models: Analysis and Improvement

Figure 3

Illustration of the images after different CEs process: (A) CE processed by LNFEs including IN, GLS, CS, GC08, LS, UM, HBF, HF, and INE, respectively (the first one is the original vein image); (B) CE processed by HEs including HE, AHE, CLAHE, and CLHE, respectively; (C) CE processed by HEM including IHE, DHE, RASF, HHE, and HEHBF, respectively.