公开(公告)号：US20210335372A1

公开(公告)日：2021-10-28

申请号：US16332583

申请日：2017-09-13

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Ryosuke SUGIURA ,  Takehiro MORIYA ,  Noboru HARADA ,  Takahito KAWANISHI ,  Yutaka KAMAMOTO ,  Kouichi FURUKADO ,  Junichi NAKAJIMA ,  Jouji NAKAYAMA ,  Kenichi NOGUCHI ,  Keisuke HASEGAWA

IPC: G10L19/035 ,  G10L19/00

Abstract: Performance of an encoding process and a decoding process for a sound signal is enhanced. A representative value calculating part 110 calculates, for each frequency section by a plurality of samples fewer than the number of frequency samples of a sample sequence of a frequency domain signal corresponding to an input acoustic signal, from the sample sequence of the frequency domain signal, a representative value of the frequency section from sample values of samples included in the frequency section, for each of predetermined time sections. A signal companding part 120 obtains, for each of the predetermined time sections, a frequency domain sample sequence obtained by multiplying a weight according to a function value of the representative value by a companding function for which an inverse function can be defined and each of the samples corresponding to the representative value in the sample sequence of the frequency domain signal, as a sample sequence of a weighted frequency domain signal.