Sign in
Search speechcoding
Subscribe to speechcoding
speechcoding by Keywords
ACELP | ADPCM | AMBE | AMR | AMR-NB | CELP | Codebook | DTMF | G.723 | G.726 | G.729 | GSM | Interpolation | LPC | LSF | LSP | MELP | PCM | Perceptual | Pitch | PSOL | QCELP | Quantization | SMV | VAD | Vocoder
Discussion Groups
Discussion Groups | Speech Coding | questions about G.723.1 and G.729
Technical discussions related to Speech Coding (all itu and other vocoders, ACELP, CELP, AMR, etc)
questions about G.723.1 and G.729 - Yidan Zhou - Dec 9 16:38:00 2002
|
Hello all, After I went through the standard document of G.723.1 and G.729, there are several technical terms I don't understand. 1. In G.723.1, what is the combinatorial coding for transmitting the pulse location? 2. In G.729, Why a low-pass filter can act as a tilt compensation filter? 3. In G.729, a bandwidth expansion is applied before the levinson durbin. It is said that expansion is used for white noise correction. Then what's the meaning of white-noise correction? Anyone knows the answers to these question, please do me a favor. Thanks in advance! Best regards, Yidan Zhou |
|
|
(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )
Re: questions about G.723.1 and G.729 - Author Unknown - Jan 17 7:43:00 2003
|
Hi all As we know in the channel vocoder each segment of input speech is analyzed using a bank of band pass filters called the analysis filters The energy at the output of the each filter is estimate at fixed intervals and transmitted to the receiver. what is that energy and how to quantify that ?? please if anybody know about basic fundametal of this please reply soon with regards "Yidan Zhou <>" <> wrote:Hello all, After I went through the standard document of G.723.1 and G.729, there are several technical terms I don't understand. 1. In G.723.1, what is the combinatorial coding for transmitting the pulse location? 2. In G.729, Why a low-pass filter can act as a tilt compensation filter? 3. In G.729, a bandwidth expansion is applied before the levinson durbin. It is said that expansion is used for white noise correction. Then what's the meaning of white-noise correction? Anyone knows the answers to these question, please do me a favor. Thanks in advance! Best regards, Yidan Zhou Yahoo! Groups SponsorADVERTISEMENT _____________________________________ Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. |
|
|
(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )
Re: questions about G.723.1 and G.729 - michel memeteau - Jan 17 23:22:00 2003
|
hi over there, What I know about it is that the energy is the fft of the filtered signal power 2 and you might divide this by the number of samples. But if you have the coder I guess you have a decoder ???? or you can find one maybe on sourceforge.org hope it helps 17/01/03 08:43:52, <> a écrit: > > à: "Yidan Zhou <>" > <>, > > De: <> > Date: Thu, 16 Jan 2003 23:43:52 -0800 (PST) > Sujet:Re: [speechcoding] questions about G.723.1 and G.729 > > Hi all > > As we know in the channel vocoder each segment of input speech is analyzed > using a bank of band pass filters called the analysis filters > The energy at the output of the each filter is estimate at fixed intervals > and transmitted to the receiver. > > what is that energy and how to quantify that ?? > > please if anybody know about basic fundametal of this please reply soon > > with regards > > "Yidan Zhou <>" <> > wrote:Hello all, > After I went through the standard document of G.723.1 and G.729, > there are several technical terms I don't understand. > 1. In G.723.1, what is the combinatorial coding for transmitting > the pulse location? > 2. In G.729, Why a low-pass filter can act as a tilt compensation > filter? > 3. In G.729, a bandwidth expansion is applied before the levinson > durbin. It is said that expansion is used for white noise > correction. Then what's the meaning of white-noise correction? > Anyone knows the answers to these question, please do me a favor. > Thanks in advance! > > Best regards, > > Yidan Zhou > > Yahoo! Groups SponsorADVERTISEMENT > > _____________________________________ > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. > > > Yahoo! Groups Sponsor > ADVERTISEMENT > HGTV Dream Home Giveaway > _____________________________________ > > Your use of Yahoo! Groups is subject to the Yahoo! Terms of Service. |
(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )