I. Introduction
Speaker verification (SV) is the task of verifying a person using his/her speech signal, which can be either text-independent (TI) or text-dependent (TD). In a TI-SV system, speakers are free to speak any text content during the system enrollment and test phases. On the contrary, TD-SV constrains a speaker to speak a particular pass-phrase from a predefined list in both enrollment and test phases. As TD-SV maintains the matched phonetic contents between training and test phases, it is superior to TI-SV for SV with short utterances and ideal for real-world applications.