Title:
VOICE CODING METHOD
Document Type and Number:
Japanese Patent JP3194481
Kind Code:
B2
Abstract:
PURPOSE: To enhance adaptability, and to enable coding of high quality.
CONSTITUTION: M copies (110 to 11M-1) of adaptation code books are prepared, and the sum of that which a gain gi has been given to an adaptation code vector Vi (i=0,1,...,M-1) therefrom and that which a gain gM has been given to a noise code vector VM from a noise code book 12 is supplied to a linear prediction synthesizing filter 13 as a driving signal for synthesizing voice, and the filter factor A of filter 13, pitch period L, noise code vector c, gains gi, gM are coded by a strain minimizing control part 14 so that the strain of the voice synthesizing waveform to the input voice can be reduced to a minimum. In the renewal of the adaptation code book 11i, Vi'=Σfi,j.Vi (i=0,1,...,M-1), where Σ is taken from j=0 to M, and the fi,j (j=0,...,M) is a weight coefficient for obtaining Vi' from Vi and VM. For instance, let f00=g0, fo1=g1, fOM=gM, fiM=gM, and in all the others, fi,j=0; then V0' becomes the driving signal of the preceding frame, and Vl' becomes the noise code vector gM.VM of the preceding frame, thus, the noise code vector of the preceding frame can be emphasized.
Inventors:
Kazunori Mano
Satoshi Miki
Takehiro Moriya
Satoshi Miki
Takehiro Moriya
Application Number:
JP27298591A
Publication Date:
July 30, 2001
Filing Date:
October 22, 1991
Export Citation:
Assignee:
Nippon Telegraph and Telephone Corporation
International Classes:
G10L19/038; G10L19/04; G10L19/06; G10L19/08; G10L19/125; (IPC1-7): G10L19/08; G10L19/00
Domestic Patent References:
| JP56200A | ||||
| JP332228A | ||||
| JP375700A | ||||
| JP2502135U |
Other References:
ＩＥＥＥ Ａｃｏｕｓｔｉｃｓ，Ｓｐｅｅｃｈ，ａｎｄ Ｓｉｇｎａｌ Ｐｒｏｃｅｓｓｉｎｇ，１９９１．ＩＣＡＳＳ−９１ Ｐａｇｅ ２３７−２４０ ｖｏｌ．１”Ｉｍｐｒｏｖｅｄ ＣＥＬＰ ｃｏｄｉｎｇ ｕｓｉｎｇ ａｄａｐｔｉｖｅ ｅｘｉｔａｔｉｏｎ ｃｏｄｅｂｏｏｋｓ” Ｋｉｐｐｅｒ，Ｕ；Ｒｅｉｎｉｎｇｅｒ，Ｈ；Ｗｏｌｆ．Ｄ
Attorney, Agent or Firm:
Suguru Kusano