Table 9: Description of process fragile bits.

MethodologyProcess method of fragile bitsResults

Hollingsworth et al. [5, 36] Masking iris code bits corresponding to complex filter response near the axes of the complex planeImprove the separation between the match and nonmatch Hamming distance distributions

Hollingsworth et al. [8]Consider the fragile bits provide beneficial information rather than ignoring fragile bits completelyScore fusion of fragile bit distance and Hamming distance works better than Hamming alone, and it improved the accuracy of matches

Hollingsworth et al. [37]Masks fragile bits value is 8.2516 compared with 7.4825 for nonmask fragile bits

Bolle et al. [7]Theoretically proved the existence of fragile bits

Dozier et al. [38]Used genetic search to minimize the number of iris code bitsApproximately reduce 89% of iris code bits and discard the fragile bits

Dozier et al. [39]Only kept bits that were 90% or 100% consistentDiscard the fragile bits

ProposedDivided normalized iris into multitracks, and fused all tracks by local quality evaluation with PSO value increase and EER decrease