| 摘要 |
<p>In coding, from a gain codebook which stores a plurality of combinations of quantized pitch gain candidates or function values thereof and quantized fixed codebook gain candidates or function values thereof with codebook indices, the most desirable codebook index is selected, at least two or more types of gain codebooks are prepared which have different concentrations of distributions of these combinations, and one of the gain codebooks is selected according to the constancy of an input audio signal. In decoding, the same gain codebooks are prepared as when coding, and one of the gain codebooks is selected according to the constancy of a decode audio signal.</p> |
