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公开(公告)号：DE3171990D1
公开(公告)日：1985-10-03
申请号：DE3171990
申请日：1981-04-30
Applicant: IBM , IBM FRANCE
Inventor： BERAUD JEAN-PAUL , ESTEBAN DANIEL , GALAND CLAUDE
Abstract: This improved speech signal Block Coded PCM (BCPCM) system reduces the number of bits allocated to transmitting the scale factor, thereby releasing bits for allocation to coding samples in the associated block of samples. The scale factor (c) is calculated for every 16 millisecond block of samples. However, the scale factor will be transmitted only once per 32 millisecond block if there is no significant difference between the two sequential values. The original speech signal is split into 16 frequency subbands, each subband initials sampled and 12-bit coded, then requantized in BCPCM at dynamically variable bit rates depending on the scale factor transmission rate.
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公开(公告)号：FR2389277A1
公开(公告)日：1978-11-24
申请号：FR7713995
申请日：1977-04-29
Applicant: IBM FRANCE
Inventor： CROISIER ALAIN , ESTEBAN DANIEL , GALAND CLAUDE
Abstract: A coding process, given a total number of available bits per unit time, allocates to each of a plurality of signal channels a number of bits proportional to information in the channel. The process is useful for transcoding BCPCM (Block Coded PCM) voice signals for lower bit rate and conserving transmission channel bandwidth.
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公开(公告)号：FR2331207A2
公开(公告)日：1977-06-03
申请号：FR7534716
申请日：1975-11-05
Applicant: IBM FRANCE
Inventor： ESTEBAN DANIEL , TEMIM JEAN-PIERRE
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公开(公告)号：DE2611906A1
公开(公告)日：1976-12-09
申请号：DE2611906
申请日：1976-03-20
Applicant: IBM
Inventor： ESTEBAN DANIEL , MENEZ JEAN
Abstract: 1506361 Block quantization process INTERNATIONAL BUSINESS MACHINES CORP 31 March 1976 [27 May 1975] 12971/76 Heading H3H To minimize error in quantizing a section Sn of N samples of a signal to be represented as where Fn is a bit stream, Q is the quantizing step and Cn a constant or polynomial, the final values of Cn and Q are arrived at iteratively. For one bit quantization a section of samples Sn‹ is loaded on to a recirculating delay line DL1 and presented to a summing point ADD 1 where an initial value Cn‹ gives Sn 1 = Sn‹ - Cn‹, fed to device QUANT producing sign derived bit stream Fn' which together with Sn' is fed to device COMP. This computes values of Cn and Q to minimize error where p is 2 for quadratic error. A new stream Fn is then calculated and the system iterates to reduce errors. For more than onebit quantization device QUANT uses the value of Q to determine Fn. A delta modulation embodiment is described, Fig. 5 (not shown), where the signal encoded Sn is the difference between an incoming signal Xn i and reconstructed signal Xn i-1 .
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公开(公告)号：CA1188423A
公开(公告)日：1985-06-04
申请号：CA401879
申请日：1982-04-28
Applicant: IBM
Inventor： BERAUD JEAN-PAUL , ESTEBAN DANIEL , GALAND CLAUDE
Abstract: IMPROVED SPEECH CODING METHOD AND DEVICE FOR IMPLEMENTING THE IMPROVED METHOD Method for coding a speech-originating signal. The spectrum of the initial signal covering a frequency range of 0-4000 Hz is split into 16 subbands, each one containing 12-bit coded samples. The samples of the 16 sub-bands are requantized in BCPCM at dynamically variable bit rates. For this, the sample flow of the sub-bands is divided into blocks of a given duration, then each block is processed for deriving therefrom two scale factors, the difference of which is analyzed to define the sample block as transient or non-transient block. For each non-transient block, only one scale factor is retained, whereas for a transient block, both scale factors are retained. The signal samples of the 16 subbands are then dynamically requantized with an overall number of bits depending on whether the block considered is transient or non-transient.
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Patent Agency Ranking
公开(公告)号：CA1127310A
公开(公告)日：1982-07-06
申请号：CA299487
申请日：1978-03-22
Applicant: IBM
Inventor： CROISIER ALAIN , ESTEBAN DANIEL , GALAND CLAUDE
Abstract: QUANTIZING PROCESS WITH DYNAMIC ALLOCATION OF THE AVAILABLE BIT RESOURCES AND DEVICE FOR IMPLEMENTING SAID PROCESS The sampled signal to be quantized is submitted to a bank of filters FB which splits the total bandwidth into p sub-bands. A device Em determines the value M of the largest sample contained in each sub-band during a predetermined time interval, a circuit LOG provides Log Mi's for i = 1,2, ..., p, then a circuit determines o = ? wherein N is the total number of quantizing bits to be used for all the p sub-bands. Then, each sub-band is quantized in a device DQ the quantizing step of which is determined from the values of M, and log M defined for the related sub-band. FR9-77-001 - 1
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公开(公告)号：DE2818052A1
公开(公告)日：1978-11-16
申请号：DE2818052
申请日：1978-04-25
Applicant: IBM
Inventor： CROISIER ALAIN , ESTEBAN DANIEL , GALAND CLAUDE
Abstract: A coding process, given a total number of available bits per unit time, allocates to each of a plurality of signal channels a number of bits proportional to information in the channel. The process is useful for transcoding BCPCM (Block Coded PCM) voice signals for lower bit rate and conserving transmission channel bandwidth.
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公开(公告)号：DE2635246A1
公开(公告)日：1977-05-12
申请号：DE2635246
申请日：1976-08-05
Applicant: IBM
Inventor： ESTEBAN DANIEL , TEMIME JEAN-PIERRE
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公开(公告)号：DE68914831T2
公开(公告)日：1994-11-17
申请号：DE68914831
申请日：1989-06-29
Applicant: IBM
Inventor： THERIAS PHILIPPE , DALMAS PHILIPPE , MICHEL PATRICK , LE PENNEC JEAN-FRANCOIS , ESTEBAN DANIEL
Abstract: A Terminal adapter for a telecommunication network having a receiver (400) for multiple HDLC communication channels. The receiver includes a BCC calculator (460) for computing and checking the validity of a received HDLC CNM frame. The terminal adapter further includes means (340, 350, 360) for detecting the reception of a specific CNM header included into a CNM frame on anyone of said HDLC communication channels and means (394, 530/X) responsive to said detection for setting the BCC calculator (460) to a predefined state. The latter state corresponds to the state of the BCC calculator (460) after a computation of BCC for the specific CNM header. Therefore the BCC calculator (460) can proceeds with computation of said BCC for said CNM frame.
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公开(公告)号：DE68914831D1
公开(公告)日：1994-05-26
申请号：DE68914831
申请日：1989-06-29
Applicant: IBM
Inventor： THERIAS PHILIPPE , DALMAS PHILIPPE , MICHEL PATRICK , LE PENNEC JEAN-FRANCOIS , ESTEBAN DANIEL
Abstract: A Terminal adapter for a telecommunication network having a receiver (400) for multiple HDLC communication channels. The receiver includes a BCC calculator (460) for computing and checking the validity of a received HDLC CNM frame. The terminal adapter further includes means (340, 350, 360) for detecting the reception of a specific CNM header included into a CNM frame on anyone of said HDLC communication channels and means (394, 530/X) responsive to said detection for setting the BCC calculator (460) to a predefined state. The latter state corresponds to the state of the BCC calculator (460) after a computation of BCC for the specific CNM header. Therefore the BCC calculator (460) can proceeds with computation of said BCC for said CNM frame.
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