| 摘要 |
<p>An audio encoding apparatus capable of improving the frame cancellation error tolerance, without increasing the number of bits of a fixed code book, in a CELP type audio encoding. In this apparatus, a low frequency component waveform encoding part (210) calculates, based on a quantized LPC received from an LPC encoding part (202), a linear prediction residual signal of a digital audio signal received from an A/D converter (112), then performs a down sampling of the calculation result to extract the low frequency components comprising bands, which are lower than a predetermined frequency, in the audio signal, and then waveform encodes the extracted low frequency components to produce encoded low-frequency component information. Then, the low frequency component waveform encoding part (210) inputs this encoded low-frequency component information to a packetizing part (231), while inputting the quantized low-frequency component waveform encoded signal (sound source waveform), which has been produced by the waveform encoding, to a high frequency component encoding part (220).</p> |
