calculate FRR and FAR

[mahsa631]

Hi
i use this for face recognition and i need calculate False rejection rate and false accept rate ,can you help me?

[ItsSantoshBehera]

FP: False positive, FN: False Negative, FN: True Negative and TP: True Positive
FAR is calculated as a fraction of negative scores exceeding your threshold.
FAR = imposter scores exceeding threshold/all imposter scores.
imposter scores exceeding threshold = FP
all imposter scores = FP+TN
FAR = FPR = FP/(FP+TN)
FRR is calculated as a fraction of positive scores falling below your threshold.
FRR = genuines scores exceeding threshold/all genuine scores
genuines scores exceeding threshold = FN
all genuine scores = TP+FN
FRR = FNR = FN/(TP+FN)