PITCH DETERMINATION APPARATUS AND METHOD USING SPECTRO-TEMPORAL AUTOCORRELATION

A pitch determination apparatus and method using spectro-temporal autocorrelation to prevent pitch determination errors are provided. The pitch determination apparatus using spectro-temporal autocorrelation includes a formant bandwidth extension unit for extending a formant bandwidth to reduce the influence of the first formant with respect to an input voice, a temporal autocorrelation calculation unit for calculating an autocorrelation value of a time axial voice within a candidate pitch range with respect to a time axial speech signal output from the formant bandwidth extension unit, a spectral autocorrelation calculation unit for transforming the time axial speech signal output from the formant bandwidth extension unit into a frequency axial signal, and calculating an autocorrelation value between frequency axis amplitude spectrums within the candidate pitch range, an autocorrelation value synthesis unit for summing the autocorrelation values obtained by the temporal and spectral autocorrelation calculation units and obtaining a spectro-temporal autocorrelation value, and a pitch determination unit for determining a pitch having a maximum spectro-temporal autocorrelation value as a final pitch. According to this apparatus, pitch determination errors are reduced by determining a pitch using the temporal and spectral autocorrelation values, thus improving the quality of speech communication.