| 摘要 |
PROBLEM TO BE SOLVED: To restore a signal similar to an original signal from a signal that represents the original signal whose spectral components in a part of the band of the original signal are suppressed, and also from a signal that represents the original signal not containing the spectral components of the band concerned, or to provide a frequency interpolation device or the like for restoring an audio signal as a high-quality sound. SOLUTION: The presence or absence of the high-pass component of the pulse code modulation(PCM) signal to be compressed is detected by a high-pass detecting part 1, meanwhile this PCM signal is compressed by a voice compression part 2, and then is outputted with external data showing the detection result of the high-pass detecting part 1. The compressed PCM signal is expanded by a voice expansion part 3. When external data show the absence of the high- pass component, the expanded PCM signal is an output signal, when the absence of the high-pass component is shown, a spectral component is added to the expanded PCM signal by a frequency interpolation part 4, and an output signal having a spectrum after interpolation is generated. |
