Speaker adaptation via VQ prototype modification

A statistical technique for vector quantizer (VQ) prototype adaptation, based on tied-mixture continuous-parameter HMM´s, is derived and evaluated on the basis of experimental evidence. Performance on difficult adaptation tasks indicates that VQ-prototype adaptation via tied-mixture HMM´s constitutes a useful mechanism for speaker adaptation, particularly when there are substantial channel differences or when there is a large mismatch between reference and target speaker characteristics.