| 摘要 |
PROBLEM TO BE SOLVED: To reduce delay time due to band extension during decoding and to restrain increase in a resource on a decoding side.SOLUTION: A higher frequency component generating unit 73 generates a pseudo higher frequency spectrum by using a lower frequency spectrum SP-L and a higher frequency envelope ENV-H. A phase random unit 74 randomizes a phase of the pseudo higher frequency spectrum on the basis of a random flag RND. A reverse MDCT unit 75 reversely normalizes the lower frequency spectrum SP-L by using a lower frequency envelope ENV-L, and combines the pseudo higher frequency spectrum, which is supplied from the phase random unit 74 with the lower frequency spectrum SP-L reversely normalized. Combination result is used as a spectrum of the whole band. This invention is applicable to, for example, a decoding apparatus performing band extension decoding. |
