SPEECH SIGNAL INTERPOLATION DEVICE, SPEECH SIGNAL INTERPOLATION METHOD, AND PROGRAM

摘要

A voice signal interpolation device for restoring compressed human voice while maintaining a high quality. When a voice signal expressing a voice to be interpolated is acquired by a voice data input unit (1), the voice signal is filtered by a pitch extraction unit (2) and the pitch length is identified according to the filtering result. A pitch length fixing unit (3) aligns the time length of an interval corresponding to a unit pitch of the voice signal and generates pitch waveform data. The pitch waveform data is converted into sub-band data expressing a spectrum by a sub-band division unit (4). After a plurality of sub-band data are averaged by an averaging unit (5), the pitch waveform data is converted into a signal expressing a voice waveform by a sub-band synthesis unit (6). The time length of the pitch of each interval of this signal is restored by a pitch restoration unit (7) and a voice expressed by this signal is reproduced by a voice output unit (8).