| 摘要 |
PURPOSE:To curtail the arithmetic quantity by calculating a time inversion auditory sense weighing input sound signal vector and multiplying it by each pitch prediction residual vector of an adaptive code book generating a correlation value of both of them. CONSTITUTION:An arithmetic means 21 calculates a time inversion auditory sense weighting input sound signal vector <1>AAX from an input sound signal vector AX subjected to auditory sense weighing. Also, a multiplying part 22 multiplies the time inversion auditory sense weighting input sound signal vector <t>AAXC and each pitch prediction residual vector P of an adaptive code book 1 and generated a correlation value t(AP)AX of both of them. Subsequently, a filter arithmetic part 23 derives a self-correlation value <t>(AP)AP of a vector AP after auditory sense weighting reproduction of each pitch prediction residual vector P of the adaptive code book 1. Moreover, an evaluating party 10 selects an optimal pitch prediction residual vector Popt and gain bopt for minimizing power of an error signal E to the input sound signal vector AX subjected to auditory sense weighting, based on both correlation values. |
