Frequency Domain Prediction of Tonal Signals With Time-Varying Pitches

In this letter, we propose an Extended Frequency Domain Joint Harmonics Prediction (EFDJHP) algorithm, which does long term prediction directly in the transform domain on tonal signals with time-varying pitches for transform speech and audio coding. EFDJHP is an algorithm extension of a previously proposed Frequency Domain Joint Harmonics Prediction (FDJHP) algorithm where a constant pitch between neighboring frames was assumed (Guo and Edler, 2021). A linearly changing pitch between adjacent frames is assumed in EFDJHP, where the linearity can be assumed to be local and updated across frames. EFDJHP works in a backward prediction fashion without additional algorithmic delay, and needs very few side information for the forward adaption of the predictor coefficients. Bitrate saving analysis and a listening test show that EFDJHP can improve the coding efficiency on tonal signals with frequent pitch variations such as singing voices and speech.