Technical discussions related to Speech Coding (all itu and other vocoders, ACELP, CELP, AMR, etc)
Search Results for "codebook"
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manoj garg - Nov 29 2001
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 del... 
jiaq...@yahoo.com - Jul 13 2005
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 periodici... 
furiousgame - Nov 24 2002
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 o... 
neeta chapatwala - Feb 20 2008
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 codeboo... 
Ray McCarthy - Oct 14 2003
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... 
Sameer Kibey - May 19 2003
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 o... 
abhi...@gmail.com - Mar 1 2006
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 vecto... 
- Nov 29 2001
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(... 
Mathew John - Jun 1 2002
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 t... 
mata mata - Aug 20 2003
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 ?
... 
Narasimha Rao B.V. - Mar 13 2000
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
und... 
adithya rao k - Oct 8 2003
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
g... 
koro - Apr 8 2004
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
codebo... 
- Oct 17 2000
Hi Friends,
in the g729a recommendation, the excitation is modelled using an
"algebraic codebook". what is meant by an "algebraic" codebook ??
also, the pos... 
Geoff Meltzner - Sep 10 2002
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. A... 
nacer_ghoul - Mar 5 2008
Hi Mehdi,
First of all, you should reply/comment to the messages through the
Group's forum, to let every one share the information, and also to get
different views/advices from ... 
Jeff Brower - Feb 25 2004
Khubaib-
> I need to know the bitstream format of the MELP's 54 bit frame.?. I
> know what are the different bits (the number of bits for different
> parameter... 
Sameer Kibey - Apr 4 2002
Hello everyone!
I have a few doubts in the ACELP part of G.723.1
encoder.
In G.723.1 ,ACELP is used for secondary residual
quantisation in 5.3 kbps rate m... 
dunjie17 - Jan 18 2005
hi all,
am new to speech coding and trying to understand the
principles. stumbled upon this website:
http://svr-www.eng.cam.ac.uk/~ajr/SA95/node87.htm... 
beatriz rodriguez - Apr 18 2002
Hi, Iīm working on G.729 but I donīt understand
exactly what is an conjugate structure codebook. Could
somebody give me a refernce.
Thanks in advance
... 
Amit Solanki - Dec 18 2006
I am working on a project on audio compression using code excited
linear prediction (CELP) techniques. My aim is to design a basic
working CELP codec in matlab. Since audio proce... 
suman_das81 - Aug 7 2002
hi all,
i want to know about ISPP design for codebook structure.
can anybody help me where can i get material for the same.
thank u
... 
John - Jul 25 2008
Try using the fixed-codebook gain (bits 87 to 91 in 12.2 kb/s). These
bits actually represent a correction factor for an estimate made in a
slightly involved way. See the AMR s... 
Pradeep Srinivasan - May 2 2002
Hi All,
My question in G.729B,
Why are we taking a fractional pitch delay T1 used
with a resolution of 1/3 in the range [58/3, 254/3]
for the 1st subframe... ![Query in Adaptive Codebook Search [Why resolution 1/3?]](/new/images/icon_more.jpg)
Mathew John - Feb 14 2002
hi,
anyone knowing the references/publications which
describes the fractional pitch lag calculations
described in the 3g 26.190 standard. (section 5.7).
I... 
tvoice_1 - Feb 7 2002
Does anyone know how to implement the G.728 codebook search
efficiently on TI's 54x device.
Also, the Levinson algorithms (50 pole) don't seem to map well to the... 
mouloud Djamah - Jul 28 2008
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) quant... 
gomzzk - Nov 20 2002
Hai,
I want to know how the probability density function(in average
distortion computation) required in determining the optimum codebook
in channel optimized vect... 
mata mata - Jul 7 2003
hi All...:)
anyone know about how to make a codebook in Vector Quantization used in CELP
coding ? how to implement Linde, Buzo, Gray (LBG) Algorithm ?
th... 
gomzzk - Nov 18 2002
Hai,
I want to know how a channel optimized matrix quantized codebook
be designed?
Is there any C source code availble on net?
If not ,how should it be designed... 
- Mar 30 2000
Dear all,
In GSM-EFR, the mean of the innovation energy is needed for the
quantization of the fixed
codebook gain. The standard mentions that this energy is 36... 
mata mata - Aug 19 2003
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... 
poonam bansal - Feb 19 2007
I am working on speech recognition using vector quantization. I am able to generate codebooks for different words separately by using vq (LBG). But i don't know how to combine the ... 
lily_yangzhou - Jul 28 2002
Dear All,
I'm now doing a transcoder between the G.723.1 and Gsm AMR. as we all
now the fixed codebook search algorithm in the reference G.723.1 cost
much MIPS... 
mata mata - Sep 19 2003
dear All,
I have some difficulties in understanding windowed sinc interpolation using FIR
filter
in adaptive codebook search process of CELP...(g729)
anyo... 
Saloni Shah - Mar 10 2006
My query is regarding the pre selection process done for quantization of gains in section 3.9.2 of ITU-T recommendation for G.729 speech codec standard. ... 
Dong-Won Lee - Oct 18 2000
1) What is algebraic
celp is a Code Excited LP
There are some kind of code, and we can express code in some ways
A tra... 
madrid_k - Nov 20 2003
dear list,
im doing my thesis on quantization of speech parameters. i need more
information on multi-stage vector quantization. aside from the paper
by LeBlanc... 
mata mata - Aug 28 2003
Hi All,
from the G729 standard
about this algebraic codevector c(n) formulation:
c(n) = [s0*G(n-m0)] + [s1*G(n-m1)] + [s2*G(n-m2)] + [s3*G(n-m3)] ; n = 0, ... ... 
shanky_b_2001 - May 5 2002
Hi all,
I am facing few problems while debugging the Standard C code of
G 723.1 for TI processors.
Problems:
1) Even after disabling the High pass filter... 