| 摘要 |
PURPOSE:To prevent the movement of filter characteristics and to remove the return noise by controlling an interpolation characteristic according to a pitch. CONSTITUTION:A coefficient generating means 14 generates (n) coefficients corresponding to a desired interpolation characteristic. A characteristic control means 15 varies the coefficients generated by the coefficient generating means 14 so as to vary and control the interpolation characteristic according to the pitch specified by a pitch specifying means 10. An interpolation arithmetic means 16 operates (n) coefficients for (n) digital waveform sample data generated by a waveform generating means 12 in order and puts them together into one-sample data to perform waveform interpolation. Further, the (n) coefficients corresponding to the desired interpolation characteristic set corresponding filter characteristics respectively at the same time. Consequently, the filter characteristics are controlled and while the waveform interpolation is performed, the return noise is securely removed at any pitch. |
