摘要 |
A interpolating signal is added to a band limit signal generated by removing the frequency components in a specified frequency band of an original signal and the resultant signal is outputted. The interpolation signal is synthesized by selecting two bands where the frequency components of the band limit signal remains and then mixing two band components extracted from the selected bands respectively, or by selecting one band where the frequency components of the band limit signal remains and then converting a frequency component extracted from a selected band to the component of other band. A signal approximate to the original signal can thereby be restored from a band limit signal generated using a signal produced by limiting the band of the original signal or an audio signal can be restored with high sound quality. |