| 摘要 |
PROBLEM TO BE SOLVED: To improve the sound quality of a synthesized waveform by correcting the error of the reproducing position of waveform data in respective bands and matching phases in a phase vocoder. SOLUTION: A waveform memory 2 stores plural pieces of mark information showing the position of an original audio waveform signal on a time base and phase/ amplitude information at every frequency band in the waveform signal. DSP 4 shows the position of the waveform signal on the time base and generates first reproduced position information changed at desired speed and second reproduced position information showing position of phase/amplitude information on the time base. Second reproduced position information shows the position of phase/amplitude information on the time base, which corresponds to a position difference from the position of the waveform signal on the time base, which first reproduced position information shows. DSP 4 reads phase information and amplitude information from the waveform memory 2 in accordance with second reproduced position information and synthesizes a reproduced audio waveform signal. When the position of first reproduced position information reaches the position of mark information of the waveform memory 2, a cosine oscillator is controlled so that the reproduced position of a divided band is controlled and the phases of the reproduced bands are matched. |
