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

Sponsor

NEW! TMS320C6474: 3x the performance. 1/3 the cost. Three 1 GHz cores on 1 chip.

Discussion Groups

Discussion Groups | Speech Coding | AMR-NB

Technical discussions related to Speech Coding (all itu and other vocoders, ACELP, CELP, AMR, etc)

Post a new Thread

AMR-NB - mani_assudani - Feb 28 2:01:00 2005

Hi friends, I have implemented complete AMR-NB Enc-Dec on proprietary DSP chip. As we know AMR-NB works on 8 rates from 12.2kb/s to 4.75kb/s. One thing I'll still not clear is - Why in 12.2kb/s rate LPC analysis is done twice as compared to other rates where LPC anaylsis is done only once. What is the overall gain ? Regards Manish

(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )

Re: AMR-NB - nacer_ghoul - Feb 28 19:09:00 2005

hi mani, doing the LPC over two overlapping windows permits to obtain a smooth evolution of the LPC parameters (and therefore enhance the quality) without using a lookahead like it is used in other codecs. This technique has been used in the EFR-GSM nacer --- In , "mani_assudani" <mani_assudani@y...> wrote: > Hi friends, > > I have implemented complete AMR-NB Enc-Dec on proprietary DSP chip. > As we know AMR-NB works on 8 rates from 12.2kb/s to 4.75kb/s. > > One thing I'll still not clear is - Why in 12.2kb/s rate LPC analysis > is done twice as compared to other rates where LPC anaylsis is done > only once. What is the overall gain ? > > Regards > Manish

(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )

Re: AMR-NB - pkon...@gmail.com - Apr 19 23:42:00 2005

hai manish, I also implemented this AMR NB codec on propreitery chip. can you tell me what is the maximum MIPS that you achieved??? regards parthu

(You need to be a member of speechcoding -- send a blank email to speechcoding-subscribe@yahoogroups.com )