公开(公告)号：US20170249947A1

公开(公告)日：2017-08-31

申请号：US15302094

申请日：2015-02-16

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION ,  THE UNIVERSITY OF TOKYO

发明人： Takehiro MORIYA ,  Yutaka KAMAMOTO ,  Noboru HARADA ,  Hirokazu KAMEOKA ,  Ryosuke SUGIURA

IPC分类号： G10L19/07 ,  G10L25/06 ,  G10L19/12

CPC分类号： G10L19/07 ,  G10L19/02 ,  G10L19/12 ,  G10L25/06 ,  G10L25/12

摘要： The present invention reduces encoding distortion in frequency domain encoding compared to conventional techniques, and obtains LSP parameters that correspond to quantized LSP parameters for the preceding frame and are to be used in time domain encoding from coefficients equivalent to linear prediction coefficients resulting from frequency domain encoding. When p is an integer equal to or greater than 1, a linear prediction coefficient sequence which is obtained by linear prediction analysis of audio signals in a predetermined time segment is represented as a[1], a[2], . . . , a[p], and ω[1], ω[2], . . . , ω[p] are a frequency domain parameter sequence derived from the linear prediction coefficient sequence a[1], a[2], . . . , a[p], an LSP linear transformation unit (300) determines the value of each converted frequency domain parameter ˜ω[i] (i=1, 2, . . . , p) in a converted frequency domain parameter sequence ˜ω[1], ˜ω[2], . . . , ˜ω[p] using the frequency domain parameter sequence ω[1], ω[2], . . . , ω[p] as input, through linear transformation which is based on the relationship of values between ω[i] and one or more frequency domain parameters adjacent to ω[i].

公开(公告)号：US20170178659A1

公开(公告)日：2017-06-22

申请号：US15327490

申请日：2015-05-15

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Takehiro MORIYA ,  Yutaka KAMAMOTO ,  Noboru HARADA

IPC分类号： G10L19/22 ,  G10L19/20 ,  G10L19/06

CPC分类号： G10L19/22 ,  G10L19/0017 ,  G10L19/02 ,  G10L19/0204 ,  G10L19/06 ,  G10L19/20 ,  G10L2019/0016 ,  H03M7/30

摘要： A coding technology that efficiently codes an input sound signal irrespective of the characteristics thereof and can obtain a decoded sound signal that sounds less artificial to a listener. A coding method codes an input sound signal frame by frame of a predetermined time segment by a selected coding processing from a plurality of types of coding processing in the frequency domain, the coding method makes it possible for a selection unit to select coding processing which is different from the coding processing of the preceding frame as coding processing of the present frame if at least one of the magnitude of the energy of high frequency components of the input sound signal of the preceding frame and the magnitude of the energy of high frequency components of the input sound signal of the present frame is smaller than or equal to a predetermined threshold value.