15. The system of claim 11 , the instructions when executed by the processor further comprising functionalities for: obtaining male training speech data of a plurality of male speakers and female training speech data of a plurality of female speakers during a training phase; determining a plurality of male pitch values based on the male training speech data and a plurality of female pitch values based on the female training speech data; determining the first pre-determined threshold based on the plurality of female pitch values; and determining the second pre-determined threshold based on the plurality of male pitch values.
15. The system of claim 11 , the instructions when executed by the processor further comprising functionalities for: obtaining male training speech data of a plurality of male speakers and female training speech data of a plurality of female speakers during a training phase; determining a plurality of male pitch values based on the male training speech data and a plurality of female pitch values based on the female training speech data; determining the first pre-determined threshold based on the plurality of female pitch values; and determining the second pre-determined threshold based on the plurality of male pitch values. 18. The system of claim 15 , the instructions when executed by the processor further comprising functionalities for: training the male GMM using the plurality of male pitch values based on expectation maximization algorithm; training the female GMM using the plurality of female pitch values based on expectation maximization algorithm; and initializing the male GMM and the female GMM by k-mean clustering.