| 摘要 |
PROBLEM TO BE SOLVED: To provide a wave form compressed or expanded in the time-base direction to express musical sound of high sound quality or the like. SOLUTION: In this device, an analog signal A is digitally converted by an A/D converter 60 to generate an original wave form x(n), operation by which amplitude information for one or more of integer periods in periodic change of an amplitude expressed by the amplitude information is duplicated to be supplemented or abbreviated is repeated by a DSP 20 in each of plural frequency bands, the time change speed of the amplitude in a term longer than a period of the periodic change of the amplitude is regulated thereby, while keeping the period of the periodic change of the amplitude, and operation by which frequency information corresponding to the amplitude information is duplicated to be supplemented or abbreviated is repeated as to the frequency information to regulate the time change speed of a frequency. A wave form of every frequency band is reproduced by this manner based on the regulated amplitude information and the frequency information, the reproduced wave forms are conbined to provide regenerated wave forms y(n) compressed or expanded in the time-base direction, and they are converted into analog signals B by an A/D converter 80. |
