Patent ID: 8000959

Claim:
A method of extracting formants, the method comprising: obtaining maximum values in a spectrum; obtaining maximum points that are possibly related to overlapped formants by checking a possible distribution of formants; searching only maximum points related to the overlapped formants, from among the obtained maximum points, by applying Cauchy's integral formula; and extracting the overlapped formants by analyzing a root using roots polishing with respect to the searched maximum points, wherein the maximum points related to the overlapped formants are obtained by: designating a region capable of overlapping two formants with one maximum value; examining whether at least two zeros are included in the designated region by applying Cauchy's integral formula only in the designated region to perform a contour integral on the designated region; and determining that a maximum point corresponding to the one maximum value is one of the maximum points related to the overlapped formants, when at least two zeros are included in the designated region.