Formant estimation of speech and singing voice by combining wavelet with LPC and Cepstrum techniques

Formants are the frequency parts of speech and singing signal those closely describe the human vocal tract geometry. Considering the growing importance of the formants, they are considered the important subject of many work. In this sense, we present two techniques for the estimation of formants, one combining Wavelet with Linear Predictive Coding (LPC) and the other combining Wavelet with Cepstral analysis. The proposed approaches uses multi-resolution analysis of wavelet transform to accurately extract the formants. The proposed techniques were tested on corpus of [a],[e],[i],[o],[u] vowels to extract speech formants, whereas singing formants were analyzed using capella singing voice of trained singers. The paper compares the formant structures of speech and singing, revealing the well-known difference, the presence of an additional formant in singing, called the singing formant, at frequencies between 2500-3000 Hz. The experimental results show the superiority of the proposed techniques in extracting formants over the conventional methods like LPC and Cepstrum.