| 摘要 |
PURPOSE:To obtain a high encoded quality even in the case of encoding at a low bit rate when sound signals are encoded by converting to frequency area by performing interpolation on the amplitude and phase and previously locally decoding frequency information. CONSTITUTION:After a peak extracting section 7 extracts the peak of amplitude components, a frequency information interpolating section 8 precisely decides an actual peak and the frequency of the peak position by performing secondary interpolation by using three points which include the extracted peak point of amplitude components and two points on both sides of the peak point. Moreover, the feature extraction of sounds is sufficiently performed by locally decoding the frequency information of the extracted peak at a locally decoding section 10 after quantization and newly deciding the amplitude and phase at the locally decoded frequency position by interpolation. Furthermore, by locally decoding the information of the frequency position in advance, discordance among parameters of frequency, amplitude, and phase is prevented. Therefore, a high encoded quality can be obtained even at a low bit rate of <=8kbps. |
