| 摘要 |
<p>A pattern matching vocoder includes first and second reference pattern memories, a pattern matching processor, and a frame selector. The first pattern memory stores reference vector patterns clustered by a distribution of the number of times of occurrence for spectral envelope vectors of an input speech signal. The second reference pattern memory stores reference vector patterns clustered by pole frequencies, pole bandwidths and a bandwidth of the input speech signal. The pattern matching processor divides the bandwidth of the speech signal into frequency regions and performs pattern matching using, as spectral envelope vectors, power ratios between the frequency regions. The frame selector performs frame selection using, as an evaluation value, a total distortion consisting of a vector distortion caused by pattern matching and a time distortion caused by frame selection with a DP scheme.</p> |
