The calculation of IJBC 1:N evaluation is different from the definition of DIR_FAR curve ?

Hi, I found that the provided calculation of 1:N evaluation in IJBC_1N.py is different from the definition of [DIR_FAR curve ](http://www.cbsr.ia.ac.cn/users/scliao/papers/Liao-IJCB14-BLUFR.pdf)for open-set identification test. Do you know what metrics are the code calculating? And, what's more, do you know where to get the official code for DIR_FAR curve calculation? Thank you very much!