| 摘要 |
PROBLEM TO BE SOLVED: To enable reproducing a sound having musical meaning and to improve expression of musical performance by extracting waveform sections successively from a waveform train traced in the reverse direction on a time base of waveform data, rearranging a waveform train, and generating reproduced waveform data. SOLUTION: Waveform sections are successively extracted in the reverse direction on a time base of waveform data using pitch information previously detected and stored in a RAM 12 based on inputted compression and expansion information. At the time of compression, extracted waveform sections are arranged on a time base for reproduction in a forward direction thinning waveforms in a section other than extracted waveform sections. At the time of expansion, extracted waveform sections are arranged on a time base for reproduction in a forward direction repeating extracted waveform sections. Waveform data of the original waveform is data in which sample value data are arranged on a time base in a forward direction, but at the time of reproduction, as sample value data is read out on a time base in a forward direction in extracted waveform sections same as the original waveform train, an order of a waveform of a reproduced waveform section is not reversed for the original waveform. |
