| 摘要 |
PROBLEM TO BE SOLVED: To provide a filter device continuously changing frequency characteristics without causing upsizing of a factor table and a circuit scale, and also without the reduction of a processing speed. SOLUTION: During normal operation, waveform data before a factor is changed over, outputted from a filter unit 12, is accumulated in a ring buffer 14b, and simultaneously waveform data delayed by a fraction of N cycles (N is an integer) of a waveform is read and outputted. After a filter factor is changed over, waveform data before the factor is changed over, read from the ring buffer 14b is cross faded to waveform data outputted from the filter unit 12 after the factor is changed over. When the cross fade is completed, waveform data outputted from the filter unit 12 after the factor is changed over is outputted while the accumulated content of the ring buffer 14b is updated, and after the completion of the update, waveform data delayed by the ring buffer 14b after the factor is changed over is read and outputted. COPYRIGHT: (C)2009,JPO&INPIT
|
