| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for restoring a high frequency including a frequency area high frequency transposer regarding encoding of an audio signal.SOLUTION: A system for generating a high frequency component of a signal from a low frequency component of the signal is constituted so as to determine a set of synthetic subband signals based on an analytic filter bank, and a part of a set of analytic subband signals by comprising: an analytic conversion unit 601 which has frequency resolution &Dgr;f; and an analytic window 611 which has duration time DA. The system comprises: a nonlinear processing unit 650 in which phases of a part of the set of analytic subband signals are shifted by a transposition degree T; a synthetic conversion unit 602 which has frequency resolution Q&Dgr;f; and a synthetic window 612 which has duration time DS, and includes a synthetic filter bank. Q is Q>1, a frequency resolution coefficient smaller than the transposition degree T, and a value of the product between frequency resolution &Dgr;f and the duration time DA of the analytic filter bank is selected based on the frequency resolution coefficient Q. |
