## voice-excited LPC and Plain LPC

Started by in Speech Coding11 years ago

hi, all i'm new in this group. please help me solve my thesis problem. I want to know about differences between voice-excited LPC and Plain LPC?...

hi, all i'm new in this group. please help me solve my thesis problem. I want to know about differences between voice-excited LPC and Plain LPC? is plain LPC same as LPC 10?! thanks before. -phitenk

## Help~~~ LPC code

Started by in Speech Coding12 years ago 2 replies

I'm currently doing my project about implementation of voice codec in DSK C5510 i'm using G723.1 as my reference of LPC but i found that is...

I'm currently doing my project about implementation of voice codec in DSK C5510 i'm using G723.1 as my reference of LPC but i found that is very hard for me to understand the code what i want is just a simple LPC for implementation Anyone have the LPC code for reference???

## LPC spectra estimate

Started by in Speech Coding10 years ago 3 replies

LPC spectra should correspond with the envelope of DFT spectra. I plot LPC spectra with matlab. The LPC spectra keep the same shape with the...

LPC spectra should correspond with the envelope of DFT spectra. I plot LPC spectra with matlab. The LPC spectra keep the same shape with the envelope of DFT spectra. But it is larger with a offset than the DFT envelope. Why? Where it go wrong? Here is the matlab script which illustrate it. N = 2560; [x,fs] = wavread('lpc.wav',N); % any speech signal can be used p=12; a =...

## CS-ACELP g.729 (interpolated LPC)

Started by in Speech Coding17 years ago

Hi all, My Q is Why we use interpolated LPC coeff for the first subframe synthesis instead of Quantized LPC coeff itself? I...

Hi all, My Q is Why we use interpolated LPC coeff for the first subframe synthesis instead of Quantized LPC coeff itself? I mean to ask, In G.729 CS-ACELP codec for speech synthesis interpolated LPC coeff are used for the 1st subframe and Quantised LPC coeff are used for

## need help about LPC 10

Started by in Speech Coding18 years ago 1 reply

hi all, sorry to disturb you again with some silly questions, but i really hit a big rock here . 1) the vocal tract of speech...

hi all, sorry to disturb you again with some silly questions, but i really hit a big rock here . 1) the vocal tract of speech production can be modeled by LPC synthesis filter, right ? it is shown by the spectral magnitude form of LPC coefficient filter that looks like a

## How to plot LPC spectrum

Started by in Speech Coding12 years ago 1 reply

Hi guys I have a 10th order LPC with...

Hi guys I have a 10th order LPC with coefficients [1.000000 -0.473154 0.638717 -0.322174 0.243055 -0.210219 0.417031 -0.452547 0.459508 -0.128858] and i want to plot the LPC spectrum. on the X axis i want to have the frequency (0Hz-4000Hz)and on the Y axis the magintude in dbs How i do that in matlab??

## Ask for the peper: "The Government Standard Linear Predictive Coding Algorithm: LPC-10".

Started by in Speech Coding11 years ago

Hi, all: Does someone of this group have this paper: "The Government Standard Linear Predictive Coding Algorithm: LPC-10". Thomas E....

Hi, all: Does someone of this group have this paper: "The Government Standard Linear Predictive Coding Algorithm: LPC-10". Thomas E. Tremain. Speech Technology Magazine, April 1982, p. 40-49 ? I am reading some papers on Linear Prediction Coding of speech signal these days. I think the FS-1015 (LPC-10) is quite suitable for me to understand the pricipal principle of LPC, but the L...

## Re: All pole LPC filter again

Started by in Speech Coding17 years ago

Hi, All the reasonings given for 10th order LPC is plausible. But i encountered 50th order filter in G.728(LD-CELP). what...

Hi, All the reasonings given for 10th order LPC is plausible. But i encountered 50th order filter in G.728(LD-CELP). what could be the probable reason for having such a high order (computationally intensive) LPC in this codec. Note: The codec is a backward a

## windowing in LPC

Started by in Speech Coding10 years ago

hi,i want to ask something. why after sampling the signal in LPC we need to windowing the file signal?? in example i use 20 ms for frame time,...

hi,i want to ask something. why after sampling the signal in LPC we need to windowing the file signal?? in example i use 20 ms for frame time, and 30 ms for frame size. fr - frame time : the LPC analysis is done starting every 20 ms in time. fs - frame size : the LPC analysis is done by windowing the speech data with a rectangular window that is 30 ms long. there is a difference between fr ...

## physical meaning of the LPC derived log area ratio coefficients?

Started by in Speech Coding15 years ago 1 reply

Hi All, The LPC derived log area ratio coefficients are defined as gi=log(1-ki/1+ki) where ki comes from the Durbin's...

Hi All, The LPC derived log area ratio coefficients are defined as gi=log(1-ki/1+ki) where ki comes from the Durbin's iterative method. I am wondering whether gi/ki (PARCOR coefficients) physically correponds to which side of the vocal tract. Suppose the LPC is of p

## LPC

Started by in Speech Coding12 years ago

Hello, I am working on LPC for full band signals. Could someone help me find the prediction gain for fullband signals(speech). I used the...

Hello, I am working on LPC for full band signals. Could someone help me find the prediction gain for fullband signals(speech). I used the prolpc.m code for the analysis. Thanks.... I am stuck here..please do help me...

## LPC & VELP SNR + VELP synthesizer

Started by in Speech Coding11 years ago

Hi, i need snr comparision of lpc-10 and voice-excited LPC (VELP) to show that velp is better as compared to lpc. and why in velp...

Hi, i need snr comparision of lpc-10 and voice-excited LPC (VELP) to show that velp is better as compared to lpc. and why in velp synthesizer, we must use DCT+noise and don't use pitch computation? by computing the pitch so we can determine whether the input speech frame is voiced or unvoiced, if we don't use pitch in synthesizer, is DCT can determine input speech voiced or unvoiced?! c...

## {need help}getting start to LPC coding

Started by in Speech Coding16 years ago 1 reply

Hi all dears. I am doing a project on vocoders[MELP]. But I am new to this field and I have not much time to go around. ...

Hi all dears. I am doing a project on vocoders[MELP]. But I am new to this field and I have not much time to go around. NOW Can anybody suggest me some thing like a tutorial or good referece on LPC coding. any suggestion is usefull to us.

## LPC to Autocorrelation Conversion

Started by in Speech Coding15 years ago

Hello Everybody, I want to write a program in C/C++ which estimates the autocorrelation values from the Linear Prediction...

Hello Everybody, I want to write a program in C/C++ which estimates the autocorrelation values from the Linear Prediction Coefficients(LPC). I would be highly obliged if anybody could help me in knowing this algorithm or sources such as books where I could find that alg

## LPC analysis window

Started by in Speech Coding11 years ago 1 reply

Hi: Which is a better LPC analysis window? Hamming or Hanning? Or, it doesn't matter? Regards, ~Arijit

Hi: Which is a better LPC analysis window? Hamming or Hanning? Or, it doesn't matter? Regards, ~Arijit

## snr estimation

Started by in Speech Coding11 years ago

Hi, i need snr comparision of lpc-10 and celp to show that celp is better as compared to lpc.can any one help. Bhargavi

Hi, i need snr comparision of lpc-10 and celp to show that celp is better as compared to lpc.can any one help. Bhargavi

## Help regarding conversion of LPC to LSP

Started by in Speech Coding15 years ago

HI I am doing CELP coding in Matlab.I have done the implementation till evaluation of LPC coefficients.Now I need to convert them...

HI I am doing CELP coding in Matlab.I have done the implementation till evaluation of LPC coefficients.Now I need to convert them to LSP. If somebody could help me with the coding or give me some tips of how to go about it,I would be really thankful. eagerly waiting for your ma

## LPC Pitch Detection Help Required

Started by in Speech Coding17 years ago

I am currently developing code using c6x DSK for determination of pitch parameters for a simple LPC using the Sondhi center clipping...

I am currently developing code using c6x DSK for determination of pitch parameters for a simple LPC using the Sondhi center clipping approach. According to this method, the speech data is first filtered at 900 Hz before it is clipped. What I want to know is : 1. I

## preemphasis filter, FIR, IIR

Started by in Speech Coding11 years ago 1 reply

hy all, 1. I want to ask, how to find the preemp coefficient 15/16=0.98..?? 2. why in LPC anlysis we using FIR & in LPC synthesis we use...

hy all, 1. I want to ask, how to find the preemp coefficient 15/16=0.98..?? 2. why in LPC anlysis we using FIR & in LPC synthesis we use IIR filter? what is the reason? thanks,,

## Scaling Data for LPC

Started by in Speech Coding17 years ago 1 reply

Hi, I am developing code for a LPC using C6711 dsk. Could someone tell me if the raw values read from AD535 codec need to be...

Hi, I am developing code for a LPC using C6711 dsk. Could someone tell me if the raw values read from AD535 codec need to be scaled to +1 to -1 range from the 32768 to -32768 range before the autocorrelation, and reflection coefficents etc are calculated ? I have noticed