## Forums Search for: Codebook

## FS-1016 Adaptive Codebook

Hi All, I'm having a bit of trouble with the adaptive codebook.From theory it seems that the codebook is a 256 x 60 array,so to...

Hi All, I'm having a bit of trouble with the adaptive codebook.From theory it seems that the codebook is a 256 x 60 array,so to speak, but from the standard code it seems that it is a 256 x 1 array and to get an adptive excitation,you select different elements of the codebook.I dont

## G729 generation of fixed codebook

inHi all, How can we find the appropriate positions(m0,m1,m2,m3) for placing the unit pulses and its sign(+/-) in the fixed codebook...

Hi all, How can we find the appropriate positions(m0,m1,m2,m3) for placing the unit pulses and its sign(+/-) in the fixed codebook vector? I mean " c(n) = s 0d(n - m 0 ) + s 1d(n - m 1 ) + s 2d(n - m 2 ) + s 3d(n - m 3 ) n = 0,...,39 The codebook vector c(n) is const

## augmented codebook construction in iLBC

Dear all, I am wondering why, in iLBC, the augmented codebook is constructed in such a way as described in RFC3951. The base and expanded...

Dear all, I am wondering why, in iLBC, the augmented codebook is constructed in such a way as described in RFC3951. The base and expanded codebooks together model periodicity in the signal, but what does the augmented codebook does? Many thanks. Jiaquan

## About MSVQ design codebook

Hi =20 I have questions and I hope that someone will reply me.=20 - I Know that for SVQ (Split vector quantization) design codebook for LSF...

Hi =20 I have questions and I hope that someone will reply me.=20 - I Know that for SVQ (Split vector quantization) design codebook for LSF = (line spectral frequencies) quantization, the centroid of each cell is calc= ulated as the mean of all vectors (belong to this cell) even if the weighte= d Euclidean distance is used while designing the codebook. This is to ensur= e that the LSF para...

## fixed/algebraic codebook in 3GPP-AMR or G729

Dear all, Can anyone give me/direct me to a DETAILED/any explanation of the fixed codebook(of G729)/algebraic codebook(of 3GPP...

Dear all, Can anyone give me/direct me to a DETAILED/any explanation of the fixed codebook(of G729)/algebraic codebook(of 3GPP AMR ACELP) with specific refrence to Qk = (x2Hck)^2 (d Ck)^2 (Rk)^2 --------- = ------ = ------- CkH HCk Ck phick Ek ...Equat

## CELP IN SIMULINK

Hello, I am doing M.Tech. project on CELP in real time using DSP kit TMS320c6713 Note that I had refer CELP demo given in simulink. ...

Hello, I am doing M.Tech. project on CELP in real time using DSP kit TMS320c6713 Note that I had refer CELP demo given in simulink. I am using simple gaussian codebook ,LPC parameters(LPC co-efficients and reflection co-efficients). My problem is how to find index for codebook? what will be gain for excitation signal coming from codebook?This gain will be constant or variable ...

## Determining sound intensity from G.729 parameters

inUsing only the G.729 parameters (codebook values, codebook indices, pitch periods, and pitch and codebook gains) or the line...

Using only the G.729 parameters (codebook values, codebook indices, pitch periods, and pitch and codebook gains) or the line spectral pairs, how can the intensity of a sound be determined?

## Adaptive Codebook generation in AMR speech codec

Hi, I am working on a project that implements CELP coding, as in AMR codec for GSM. The codec uses a 'codebook' to store 'code vectors', which...

Hi, I am working on a project that implements CELP coding, as in AMR codec for GSM. The codec uses a 'codebook' to store 'code vectors', which are compared with excitation vectors and the error minimised till a match is found. This match is used to synthesise speech. The spec I am using, 3GPP TS 26.090 ver 6.0.0, r6, specifies codebook architecture but not how it is created. So how is this

## regarding adaptive c/b in AMR encoder

inhi all in the AMR standard, a signal called y[n] is used. it is the "filtered adaptive codebook vector" and is defined as: ...

hi all in the AMR standard, a signal called y[n] is used. it is the "filtered adaptive codebook vector" and is defined as: y[n] = v[n]*h[n] (read convolution of v[n] and h[n]), where v[n] => adaptive codebook vector and h[n] => impulse response of teh wei

## Regarding Algebraic Codebook in CELP

Hi all, I need help in estimating the positions and pulses of algebraic codebook it is said in the standards (etsi 05.90) : ...

Hi all, I need help in estimating the positions and pulses of algebraic codebook it is said in the standards (etsi 05.90) : "First, for each of the five tracks the pulse positions with maximum absolute values b(n) are searched.From global maximum value for all the pulse p

## Need optimum adaptive codebook gains in G.723.1

Dear all! I am fresh in speech coding, and now I use the G.723.1 to compress our TTS database. I want to retrain the two gain...

Dear all! I am fresh in speech coding, and now I use the G.723.1 to compress our TTS database. I want to retrain the two gain tables used in the adaptive codebook which are 85 and 170 entries. Now I need the "optimum" values(i.e.,the unquantized values) of those 5

## Gain predicition in G729

Hiii, In the G 729 encoder part the gain prediction block(3.9.1 in ITU document) is confusing. I was not able to find the way...

Hiii, In the G 729 encoder part the gain prediction block(3.9.1 in ITU document) is confusing. I was not able to find the way to calculate the fixed codebook gain and the gamma value. I am not able to find the flow of the calculating the fixed codebook gain. I don't know eithe

## some queries about g729a codec

Hi Friends, in the g729a recommendation, the excitation is modelled using an "algebraic codebook". what is meant by an...

Hi Friends, in the g729a recommendation, the excitation is modelled using an "algebraic codebook". what is meant by an "algebraic" codebook ?? also, the postfiltering stage of the decoder uses a tilt compensation filter to compenstate for the spectra

## Regarding algebraic codebook search of CELP

Hi all, did anyone had builded a matlab function of algebraic codebook search in CELP ? is it possible to build a simulation...

Hi all, did anyone had builded a matlab function of algebraic codebook search in CELP ? is it possible to build a simulation program of CELP using matlab ? -regards arida ---------------------------------

## G728

hi, i am working on G728. I read in a book that codebook structuring is done in G728. However in itu-t document for G728 "coding...

hi, i am working on G728. I read in a book that codebook structuring is done in G728. However in itu-t document for G728 "coding of speech at 16kbps using low delay code excited linear prediction" i didn't find codebook structuring. So is there any itu-t document wher

## IS-54 VSELP source code and/or codebook parameters

Hi, I am working on an old two-way radio simulation project running on 8000bps sampling rate using the VSELP vocoder. Does anyone here...

Hi, I am working on an old two-way radio simulation project running on 8000bps sampling rate using the VSELP vocoder. Does anyone here still have the IS-54 VSELP source code or at least a sample of sotchastic codebook parameters(1024 with order of 10)? Not sure, if it's really GSM-HR. Perhaps, something similar to this bit allocation: (from an old TI tech paper) MODE 2b Voicing Mode ...

## Depth first search in G729A speech coder

inHi there, somebody please explain me about the depth first codebook search algorithm used in G729A (CS-ACELP). Also suggest...

Hi there, somebody please explain me about the depth first codebook search algorithm used in G729A (CS-ACELP). Also suggest some references (if any) to understand the logic behind the depth first search algorithm (specific to G729A codebook search). Th

## CS_ACELP information

inHi, I?m working on G.729 but I don?t understand exactly what is an conjugate structure codebook. Could somebody give me a...

Hi, I?m working on G.729 but I don?t understand exactly what is an conjugate structure codebook. Could somebody give me a refernce. Thanks in advance

## adaptive codebook - 3gpp 26.190

hi, anyone knowing the references/publications which describes the fractional pitch lag calculations described in the 3g...

hi, anyone knowing the references/publications which describes the fractional pitch lag calculations described in the 3g 26.190 standard. (section 5.7). I find it difficult to follow what they are saying there.... john

## G729 adaptive codebook

Hi, I am currently trying to write a Matlab implementation of the G.729 codec and right now, the output of my decoder sounds less...

Hi, I am currently trying to write a Matlab implementation of the G.729 codec and right now, the output of my decoder sounds less than normal, to say the least. As such, I have a couple of questions that I hope that someone on this list can help me with: 1. In the decode