## levinson durbin

Started by in comp.dsp8 years ago 1 reply

I was trying to implement Linear Predictive Coding in Matlab. The program I wrote for Levinson Algorithm gives same coefficients as Matlab's...

I was trying to implement Linear Predictive Coding in Matlab. The program I wrote for Levinson Algorithm gives same coefficients as Matlab's levinson function. But i found out that Matlab's lpc function gives different set of coefficients. Why is it so? _____________________________ Posted through www.DSPRelated.com

## Levinson-Durbin Vs Generalezed Levinson-Durbin algorithm

Started by in comp.dsp16 years ago

Good morning experties, I'm using the generalized Levinson-Durbin algrithm to solve the system R*hinv=q. Where q(l)=h(N-l), N is the length of...

Good morning experties, I'm using the generalized Levinson-Durbin algrithm to solve the system R*hinv=q. Where q(l)=h(N-l), N is the length of the filter to be inverted and hinv is its inverse. R is a symmetric Toeplitz matrix. I used the MATLAB code from Bob Cain in http://www.musicdsp.org/showone.php?id=188 which work very well. But I can't understand why it works! Could you please help ...

Started by in comp.dsp18 years ago 11 replies

Hi All, I'm just confusing myself with predictors and the Levinson-Durbin algorithm. I've got Haykin's book. So... near the start of the...

Hi All, I'm just confusing myself with predictors and the Levinson-Durbin algorithm. I've got Haykin's book. So... near the start of the book there are diagrams of the different adaptive filter models. I am familar with the identification model and LMStype algorthims. But I'm trying to understand the predictor and Levinson-Durbin algorthim. Do these two go together?! In the predictor...

## faster algorithm than levinson-durbin recursion

Started by in comp.dsp17 years ago 1 reply

Hello I am looking for a _stable_ algorithm that performs better in terms of speed than the levinson-durbin recursive algorithm. Any...

Hello I am looking for a _stable_ algorithm that performs better in terms of speed than the levinson-durbin recursive algorithm. Any suggestions? Thank you.

## Levinson algo. wtih complex coef. required

Started by in comp.dsp19 years ago 7 replies

Hi, I am desperatly looking for a generalized Levinson algorithm that can cope with complex autocorrelation values and giving complex filter...

Hi, I am desperatly looking for a generalized Levinson algorithm that can cope with complex autocorrelation values and giving complex filter coefficients... I would like to implement it in C, and i have only found the classical LPC analysis but it can not deal with complex coefficients... Anyone can help ? Thanks in advance

## levinson durbin algorithm

Started by in comp.dsp12 years ago 3 replies

Why does the 10th order levinson durbin algorithm return these LP coefficients LPC 1 ...

Why does the 10th order levinson durbin algorithm return these LP coefficients LPC 1 -141.987085255646 379.380008989783 -652.562624856013 914.226857127382 -1069.00679555295 1068.49193530997 -912.915274765544 650.564278635448 -377.394102649473 140.21469138077 ...

## Need help about stability of Levinson-Durbin algorithm in Matlab

Started by in comp.dsp17 years ago 2 replies

Hi, expertises, I am programming levinson-durbin algorithm in Matlab and desperately find that it comes out with unstable results, especially...

Hi, expertises, I am programming levinson-durbin algorithm in Matlab and desperately find that it comes out with unstable results, especially for the multivariate case. Is there any standard, stable matlab pragramme about this algorithm available for reference? Thanks a lot.. Ken

## Levinson-Durbin Recursion revisited

Started by in comp.dsp14 years ago 4 replies

I know this subject has been discussed in the past on this site in relation to inverse filter design, and this is also the subject of this post....

I know this subject has been discussed in the past on this site in relation to inverse filter design, and this is also the subject of this post. My specific application is acoustics. If you have experience with the Levinson-Durbin algorithm in C/C++ I could use your help. I have been using the code found at http://kbs.cs.tu-berlin.de/~jutta/gsm/lpc.html to try to implement the algorithm in C t...

## vhdl (verilog) code for levinson durbin algorithm

Started by in comp.dsp11 years ago 9 replies

hello, I now looking for any code for implementation of levinson-durbin algorithm on fpga. Can you help me? Regards

hello, I now looking for any code for implementation of levinson-durbin algorithm on fpga. Can you help me? Regards

## Levinson-Durbin algorithm

Started by in comp.dsp16 years ago 1 reply

Good morning experties, I'm using Levinson-durbin algorithm to invert room impulse responses. I used the MAtLAB code writen by Bob Cain in...

Good morning experties, I'm using Levinson-durbin algorithm to invert room impulse responses. I used the MAtLAB code writen by Bob Cain in the following page http://www.musicdsp.org/showone.php?id=188 The code works well, but I can't understand why it works! The following equation should be solved : R*hinv = q Where R is a Toeplitz matrix, hinv the wanted inverse filter and q is a well kn...

## calculating gain with levinson-durbin.

Started by in comp.dsp17 years ago 7 replies

Hi, I'm using the levinson-durbin algorithm to calculate an all-pole filter. This all-pole filter is used to generate background noise to...

Hi, I'm using the levinson-durbin algorithm to calculate an all-pole filter. This all-pole filter is used to generate background noise to overcome silence when the telephone line is muted. I believe a description of the all-pole filter is : H(z) = G / (a0+a1*z-1 + a2*z-2....). Calculating the denomenator in Matlab is not a problem, using the following line of matlab code: [...

## Fixed-point implementation of levinson durbin algorithm

Started by in comp.dsp9 years ago 17 replies

Hi, Any links to a fixed point implementation of the Levinson Durbin algorithm ...something like this: void levdur(pLpcCoeff, pAutoCorr,...

Hi, Any links to a fixed point implementation of the Levinson Durbin algorithm ...something like this: void levdur(pLpcCoeff, pAutoCorr, pReflec, nOrder) where pLpcCoeff is a pointer to the lpc coefficients where pAutoCorr is a pointer to the autocorrelation coefficients (range -40 to 40) where pReflec is a pointer to the reflection coefficients where nOrder is 10 The autocorrelat...

## Input parameters of Levinson-Durbin algorithm

Started by in comp.dsp17 years ago 1 reply

Hello experties, I'm using Durbin-Levinson algorithm to calculate the inverse impulse response of a given impulse response h in the time...

Hello experties, I'm using Durbin-Levinson algorithm to calculate the inverse impulse response of a given impulse response h in the time domaine. The algorithm requires three input parameters: - Impulse response h - The delay time of the inverse impulse response of h - The length of the inverse impulse response Is there any methode to estimate The delay time and the length of the inverse i...

## Order selection of AR process

Started by in comp.dsp16 years ago 3 replies

Hi Can anyone explain how one choses the order of the AR process when trying to estimate it's coefficient (Via levinson durbin algorithm). Is...

Hi Can anyone explain how one choses the order of the AR process when trying to estimate it's coefficient (Via levinson durbin algorithm). Is this a try and error? Thanks

## Linear predictive coefficient computation

Started by in comp.dsp17 years ago 2 replies

To find the Linear predictive coefficents all are using auto correlation with levinson durbin equation. I want to know is there any alternative...

To find the Linear predictive coefficents all are using auto correlation with levinson durbin equation. I want to know is there any alternative method availble that still reduces the computational complexity to find the LPC coefficients.

## Levinson Durbin / Reflection coefficients

Started by in comp.dsp19 years ago 1 reply

Hi ! I want to learn more about different representations of the LP coefficients (ie reflection coefficients, spectral frequency line, and...

Hi ! I want to learn more about different representations of the LP coefficients (ie reflection coefficients, spectral frequency line, and so on). How to transform between those representations and what they actually mean. I'm searching for an easy representation which is robust against quantization and also allows the signal to be losslessly coded. (It should be easy to calculate the...

## Help in understanding Levinson Durbin

Started by in comp.dsp16 years ago 3 replies

Hello friends, I am an undergraduate student from India and have taken up Advanced DSP as my course. I am referring to the book by Proakis...

Hello friends, I am an undergraduate student from India and have taken up Advanced DSP as my course. I am referring to the book by Proakis and Manolakis. I have thoroughly read upto filters. However, I find the Linear Prediction chapter a bit heavy to understand. I find the derivations diff to understand and would love to see proofs where a bit more of the intermediate steps too are sho...

## should first coef of spiking decon Wiener filter be positive?

Started by in comp.dsp7 years ago

Spiking decon has been used in geophysics for over 50 years. An FIR Wiener filter is computed by Levinson recursion. The inputs are the...

Spiking decon has been used in geophysics for over 50 years. An FIR Wiener filter is computed by Levinson recursion. The inputs are the autocorrelation of the trace, and an impulse (1,0,0,0,...) as desired signal. It is based on certain assumptions, such as the wavelet being minimum phase and stationary (which are only approximations in reality). Now I have been looking at an open-source pac...

## levinson durbin algo (again)

Started by in comp.dsp12 years ago 4 replies

Hi, I keep on getting a divide-by-zero exception when I execute the following code: Can somebody please tell me where my fixed-point math...

Hi, I keep on getting a divide-by-zero exception when I execute the following code: Can somebody please tell me where my fixed-point math is "broken" ??? Thank you! void levinsonDurbin(SINT32 *a, SINT32 *k, SINT32 *r, SINT32 n) { SINT32 a_temp[10+1], alpha, epsilon; int i, j; SINT32 tmpval; k = 0; a = 32768; a_temp = 32768; alpha =...

## autocorrelation with 0 lag for LPC in speex library

Started by in comp.dsp17 years ago

Hi, I saw in the sources for the speex library (http://www.speex.org/) that they add some value to the first autocorrelation result. The...

Hi, I saw in the sources for the speex library (http://www.speex.org/) that they add some value to the first autocorrelation result. The results are used to produce a IIR with a levinson durbin recursion. float d; int i; while (lag--) { for (i = lag, d = 0; i < n; i++) d += x[i] * x[i-lag]; ac[lag] = d; } ac += 10; ^^^^^^^^^^^^