The computation and some spectral considerations on line spectrum pairs (LSP)

ln this paper two aspects of Une Spectrum Pair (LSP) representation of speech are investigated: the method of converting Linear Predictive Coding (LPC) coefficients to LSP frequencies and the relationships between LPC spectrum and LSP frequencies. A new approach to LSP extraction is proposed which exploits the interframe redundancy of LSP frequencies in order to ensure, on the average, a low computational complexity. Soma spectral properlies of the LSP frequencies are then described. Starting from these properties, an LSPbased distance measure is introduced which approximates the rms log spectral measure and can be easily evaluated in parallel with the extraction procedure, in order to obtain a preliminary segmentation of speech.