A phase codebook model for PWI speech coding

A prototype encoding technique for prototype waveform interpolation speech coding is proposed which uses spectral magnitude and phase codebooks. It is shown that the phase codebook can be searched based on a simple peak picking procedure which results in an implicit alignment of the prototypes. This fast search technique allows for the use of relatively large phase codebooks. Experimental results show significant performance improvement compared to systems using direct time-domain vector quantization of the prototype waveforms