公开(公告)号：DE3783905D1

公开(公告)日：1993-03-11

申请号：DE3783905

申请日：1987-03-05

Applicant: IBM

Inventor： GALAND CLAUDE ,  ROSSO MICHELE ,  LIETHOUDT THIERRY ,  ELIE PHILIPPE ,  LANCON EMMANUEL ,  CREPY HUBERT

IPC: G01H3/04 ,  G10L19/08 ,  G10L9/14

Abstract: The digital process includes setting signal dependent positive threshold (Th+) and negative threshold (Th-). Samples representative of the signal block are located and stored having magnitudes above and below the thresholds. Significant sign transitions are located within the stored samples. The number M' of stored samples between the consecutively located significant transitions is computed and a rough value M is computed as the mean value of M'. Autocorrelation zones are set about the multiples of M spaced peak samples and the considered block of signal samples is split into consecutive sub-blocks. A current sub-block of samples is autocorrelated with sub-blocks of samples the first of which is one sample of an autocorrelation zone.

公开(公告)号：DE3683767D1

公开(公告)日：1992-03-12

申请号：DE3683767

申请日：1986-04-30

Applicant: IBM

Inventor： GALAND CLAUDE ,  MENEZ JEAN

IPC: H04B14/04 ,  G10L19/06 ,  H03M7/30 ,  G10L9/14

Abstract: The voice signal is analyzed to derive therefrom a low frequency base band signal, linear prediction coefficients and HF descriptors. Said HF descriptors include HF energy indications as well as indications relative to the phase shift between the low frequency and the high frequency band. Said HF descriptors are used during the voice synthesis operation to provide an inphase HF bandwidth component to be added to the phase band prior to be used for driving a linear prediction synthesis filter tuned using said linear prediction parameters.

公开(公告)号：CA1284679C

公开(公告)日：1991-06-04

申请号：CA535922

申请日：1987-04-29

Applicant: IBM

Inventor： GALAND CLAUDE ,  VERMOT-GAUCHY ROBERT ,  ROULIER GUY ,  CERF-DANON HELENE

IPC: H04L27/00 ,  H04L27/26 ,  H04Q1/457 ,  H04M1/00

Abstract: TONE DETECTION PROCESS AND DEVICE FOR IMPLEMENTING SAID PROCESS The process is made to detect a received tone including at least one single predetermined frequency, within a signal encoded using block coding and Linear Prediction Coding techniques providing auto-correlation coefficients R(i) and direct form coefficients a(i). The process is based upon Fourier Transform computations over the successive blocks of a(i)'s, with table look up tone identification, further confirmed upon R(i)'s stationarity detecting.

公开(公告)号：DE3576772D1

公开(公告)日：1990-04-26

申请号：DE3576772

申请日：1985-04-30

Applicant: IBM

Inventor： PLATEL GUY ,  GALAND CLAUDE

IPC: H04B3/20 ,  H04B3/23

公开(公告)号：CA1245780A

公开(公告)日：1988-11-29

申请号：CA462994

申请日：1984-09-12

Applicant: IBM

Inventor： CALLENS PAUL ,  GALAND CLAUDE ,  PLATEL GUY ,  VERMOT-GAUCHY ROBERT

IPC: G11C11/41 ,  G10L19/02 ,  G11C11/411 ,  H03K3/286 ,  H04B1/66 ,  H04L1/00 ,  H04J3/02

Abstract: A method of reconstructing, at the receiving end, digital data defining an encoded voice signal segment lost in transmission between the transmitter and the receiver in a transmission system wherein a low-frequency signal such as a residual baseband signal is derived at the transmitting end from the signal to be encoded and is then distributed among several sub-bands whose sampled contents are quantized separately. The reconstruction method includes a step of analyzing the received signal to detect any missing segment thereof and, as the case may be, to initiate an analysis, within each sub-band, of the segment(s) adjacent to the lost segment, so as to generate a term relating to the period T(k) of the signal so analyzed and to reconstruct a segment of signal of period T(k) intended to be substituted for the lost segment.

公开(公告)号：CA1231473A

公开(公告)日：1988-01-12

申请号：CA454771

申请日：1984-05-18

Applicant: IBM

Inventor： DESBLACHE ANDRE ,  GALAND CLAUDE ,  VERMOT-GAUCHY ROBERT

IPC: G10L11/02 ,  H04J3/16 ,  H04J3/17

Abstract: In a transmission system for transmitting voice signals each signal being sampled and coded to derive therefrom blocks of samples and short term power spectrum characteristics or each block, a voice activity detection process is proposed wherein an energy representative information is derived from each block of sample, which energy representative information is compared with a predetermined threshold and said threshold is adjusted accordingly. Then an active/ambiguous decision is taken based on the relative magnitude of the energy information with respect to the adjusted threshold, which ambiguity is then eventually resolved through analysis of the magnitude of variation of the short term power spectrum characteristics.

公开(公告)号：CA1206280A

公开(公告)日：1986-06-17

申请号：CA420117

申请日：1983-01-24

Applicant: IBM

Inventor： GALAND CLAUDE

IPC: G10L13/00 ,  G10L19/00 ,  H03M7/30 ,  H04B1/66 ,  H04B14/04 ,  H04J3/17 ,  H04J3/22

Abstract: MULTIRATE DIGITAL TRANSMISSION METHOD AND DEVICE FOR IMPLEMENTING SAID METHOD The method uses BCPCM techniques for coding the signal into subbands by dynamic allocation of the coding bits between the subbands, the rate of all subbands together being chosen so as to be the highest one in a set of predetermined rates. The bits obtained by coding the samples of the subbands considered at a given sampling instant (macro sample) are distributed according to a given format comprising a predetermined number of fields of a predetermined size. The distribution of said bits depends on the rank of each bit in the sample to which it belongs and on its contribution to the coding at each of the predetermined coding rates.