Abstract: The various embodiments herein provide a system and method to track the pitch of a human being in real time using time varying model. According to one embodiment, the input voice is synthesised to obtain a lower order model. The lower model is down sampled and fitted to a time varying 2nd order model. The down sampled signal is passed through a pitch tracking filter, a fading filter and a gradient filter to obtain a pitch signal in real time. The noise included in the pitch signal is removed by passing the acquired pitch signal through a Kalman filter to obtain a smoothened pitch signal in real time.

Abstract: An information extraction unit extracts spectral envelope information of L-dimension from each frame of speech data. The spectral envelope information does not have a spectral fine structure. A basis storage unit stores N bases (L>N>1). Each basis is differently a frequency band having a maximum as a peak frequency in a spectral domain having L-dimension. A value corresponding to a frequency outside the frequency band along a frequency axis of the spectral domain is zero. Two frequency bands of which two peak frequencies are adjacent along the frequency axis partially overlap. A parameter calculation unit minimizes a distortion between the spectral envelope information and a linear combination of each basis with a coefficient by changing the coefficient, and sets the coefficient of each basis from which the distortion is minimized to a spectral envelope parameter of the spectral envelope information.

Abstract: A time shift calculated during a pitch-regularizing (PR) encoding of a frame of an audio signal is used to time-shift a segment of another frame during a non-PR encoding.