Title (en)

METHOD AND APPARATUS FOR LOW BIT RATE TRANSMISSION OF A SPEECH SIGNAL USING CELP CODING

Publication

EP 0481895 A3 19920812 (FR)

Application

EP 91402774 A 19911017

Priority

FR 9012980 A 19901019

Abstract (en)

[origin: EP0481895A2] The invention relates to a method for low bit rate transmission of a digital speech signal. <??>The coding is effected by linear prediction driven by codes in order to generate a code signal, a wave form being represented by an initial vector (O) of dimension L, from a filter for synthesis by a reference wave form selected from among a dictionary of reference vectors (v), with a minimum deviation criterion min ¦¦x-H.v¦¦<2>, x representing a target vector by perceptual weighting of the initial vector (O). A dictionary (Y) factorised as a product of base vectors yi of n-ary form, corrected by a scale factor gamma i of distribution of the excitation energy, and of a dictionary G(y) of gains gk, are established in order to represent the dictionary of the reference vectors (v), vk,i = gk. gamma i.yi. The criterion is established by calculation of C(gk, gamma i.yi) = 2 gk<x¦H. gamma i.yi>-gk<2> ¦¦H. gamma i.yi¦¦<2> formed by the scalar products and perceptual energies. To the initial vector (O) is attributed the optimal reference vector vk<*>, i<*> = gk<*>.i<*>.yi<*> represented only by the index values k<*>,i<*>. <??>Application to coding and transmission of speech at a low bit rate by ternary or n-ary vectors. <IMAGE>

IPC 1-7

G10L 9/14

IPC 8 full level

G10L 19/12 (2013.01); H04B 14/04 (2006.01)

CPC (source: EP US)

G10L 19/083 (2013.01 - EP US); G10L 19/12 (2013.01 - EP US); G10L 2019/0005 (2013.01 - EP US); G10L 2019/0007 (2013.01 - EP US)

Citation (search report)

• [XP] WO 9113432 A1 19910905 - UNIV SHERBROOKE [CA]
• [A] EP 0379296 A2 19900725 - AMERICAN TELEPHONE & TELEGRAPH [US]
• [A] ADVANCED IN SPEECH CODING (IEEE WORKSHOP ON SPEECH CODING FOR TELECOMMUNICATIONS, Vancouver, 5 - 8 septembre 1989), pages 145-156, Kluwer Academic Publishers, Dordrecht, NL; R.A. SALAMI: "Binary pulse excitation: a novel approach to low complexity CELP coding"

Designated contracting state (EPC)

DE GB

DOCDB simple family (publication)

EP 0481895 A2 19920422; EP 0481895 A3 19920812; EP 0481895 B1 19971210; DE 69128407 D1 19980122; DE 69128407 T2 19980604; FR 2668288 A1 19920424; FR 2668288 B1 19930115; JP 3130348 B2 20010131; JP H04264500 A 19920921; US 5226085 A 19930706

DOCDB simple family (application)

EP 91402774 A 19911017; DE 69128407 T 19911017; FR 9012980 A 19901019; JP 29809691 A 19911018; US 77931091 A 19911018