| 摘要 |
<p>An audio data input unit (310) of an encoding device 300 splits an audio data string into contiguous 4,096 samples of audio data, and a transforming unit (320) transforms the split audio data into spectral data in a frequency domain. A data dividing unit (330) divides the spectral data into that in a lower frequency band and that in a higher frequency band at 11.025 kHz (f1) as a boundary. The spectral data in the lower frequency band is quantized and encoded by a first quantizing unit (340) and an encoding unit (350) as usual. A second quantizing unit (345) generates sub information indicating a characteristic of the spectral data in the higher frequency band, and a second encoding unit (355) encodes the sub information. A stream output unit (390) integrates the codes obtained by the first and second encoding units (350), (355), and outputs the integrated one. Here, the f1 is a half or less of a sampling frequency f2 at which the audio data string is created.</p> |
