Request the information.

Started by HyungJung Kim in Speech Coding19 years ago

Hello all, I am very interesting in speech. The compexity and memory size AMR codec and draft SMV...

Hello all, I am very interesting in speech. The compexity and memory size AMR codec and draft SMV was released.  


GSM EFR Vs GSM AMR

Started by Anonymous in Speech Coding18 years ago

Nice to have found an interesting site to discuss speech coding stuff. On the first look it looks like GSM AMR and GSM EFR...

Nice to have found an interesting site to discuss speech coding stuff. On the first look it looks like GSM AMR and GSM EFR have lot of commonolity. Standard says GSM AMR at rate 12.2k behaves exactly like GSM EFR. So it looks like GSM EFR is subset of GSM AMR. Can


gsm amr

Started by Mr kiran nayak in Speech Coding18 years ago

Hello All, I am working on GSM_AMR and would like to know of the given test vectors which test vectors will give best results of...

Hello All, I am working on GSM_AMR and would like to know of the given test vectors which test vectors will give best results of profiling when used for different bit rates. The mode is full rate. Thanking you in anticipation, Kiran =====


AMR Codec VAD

Started by Harsha in Speech Coding17 years ago 2 replies

Hi All,      Please let me know the actual difference between VAD option 1

Hi All,      Please let me know the actual difference between VAD option 1


AMR with RTP

Started by Harsha in Speech Coding17 years ago 2 replies

Hi All, In RTP payload format for AMR, how is it that the sender side will determine that the frame is severely damaged ? (It...

Hi All, In RTP payload format for AMR, how is it that the sender side will determine that the frame is severely damaged ? (It is mentioned that if Q bit is not set, then it indicates that the frame is severely damaged and the receiver should set RX_TYPE to SPEECH_BAD or


GSM AMR - EFR Test Vectors

Started by vipinpathak in Speech Coding17 years ago

Hi All; I want to know if there are additional Test Vectors for the GSM AMR and EFR codecs, apart from the ones provided by the...

Hi All; I want to know if there are additional Test Vectors for the GSM AMR and EFR codecs, apart from the ones provided by the ETSI and 3GPP. Thanks Vipin


Additional 5 ms look-ahead delay in AMR12.2k

Started by manoj garg in Speech Coding17 years ago

Dear friends, i am working on EFR compatible AMR. In one of the documents presented at 3gpp meeting by Ericsson i find the...

Dear friends, i am working on EFR compatible AMR. In one of the documents presented at 3gpp meeting by Ericsson i find the following statement: "AMR 12.2 has 5 ms longer delay than GSM EFR which is caused by the (dummy) look-ahead of 5 ms (added to allow seamless fra


look-ahead in AMR why?

Started by manoj garg in Speech Coding17 years ago 1 reply

Dear friends, > i am learning AMR-NB. In the specifications i found > that the look-ahead is used in all modes except 12.2k >...

Dear friends, > i am learning AMR-NB. In the specifications i found > that the look-ahead is used in all modes except 12.2k > mode. my doubts are: > 1- What is the adavantage of using 5 ms look-ahead > while there is no look-ahead in 12.2k mode. what is


bit rate algorithm in AMR

Started by adangaja in Speech Coding17 years ago

Dear All Actually I am a new member of this mailing list. First of all my name is adangaja, and I am in the last semester in...

Dear All Actually I am a new member of this mailing list. First of all my name is adangaja, and I am in the last semester in STTTelkom Indonesia. I have a project about AMR. I've got documents about AMR from ETSI, but unfortunately none of them explain about the algorithm to d


AMR

Started by phil_lancs2002 in Speech Coding16 years ago 1 reply

Hey I'm working on a CELP AMR codec. The coder uses previous samples of the input speech, for windowing or creating the past...

Hey I'm working on a CELP AMR codec. The coder uses previous samples of the input speech, for windowing or creating the past excitation. So, my question is: what happened for the first frame ? Thank you, Phil.


AMR IF2 format bit-stream decoding

Started by biswasbiswajit in Speech Coding17 years ago

Hi, I am not able to decode the bit-stream syntax format of AMR IF2 (Octate frame stucture) as explained in Table A.2 of Annex...

Hi, I am not able to decode the bit-stream syntax format of AMR IF2 (Octate frame stucture) as explained in Table A.2 of Annex A of document Ts 26.101 V1.0.0. can anyone give a hint how the bit-stream is to be parsed for MAR IF2 format? Many thanks in


Few general queries on AMR

Started by subrata_etc in Speech Coding17 years ago 2 replies

hi friends, I have just started working with AMR speech codec. I would like post few general queries which are written below.......

hi friends, I have just started working with AMR speech codec. I would like post few general queries which are written below.... 1)What is the application of different bit rates(12.2,10.2,7.95,7.40,6.70,5.90,5.15,4.75 kbits/sec in practical field? 2)After usi


few fundamental questions on AMR speech coding

Started by subrata chatterjee in Speech Coding17 years ago

Hi friends, I have some fundamental queries regarding AMR speech codec. 1) Why we are using two windows in case of ...

Hi friends, I have some fundamental queries regarding AMR speech codec. 1) Why we are using two windows in case of 12.2kbit/sec mode? 2)What is the utility of using auto correlation after windowing? 3)What is the utility of using lag wind


Why high pass filtering and down scaling in pre processing

Started by subrata chatterjee in Speech Coding17 years ago 4 replies

hi friends, In AMR speech codec why do we need to use high pass filtering and down scaling in pre processing??? Again the...

hi friends, In AMR speech codec why do we need to use high pass filtering and down scaling in pre processing??? Again the technique of down scalling is not clear to me....So please anyone help me by answering the above queries in detail. Thanks in advance Sub


AMR decoder

Started by biswasbiswajit in Speech Coding17 years ago

Hi, When implementing AMR decoder from scratch as explained in 3GPP standard, I am facing lot of doubts. Decoding fucntions are...

Hi, When implementing AMR decoder from scratch as explained in 3GPP standard, I am facing lot of doubts. Decoding fucntions are not explained properly in the standard. For example, DTX handling in decoder side is understandble in reference source code , but nothing is explained


bit rate ??

Started by hambali hambali in Speech Coding17 years ago

hi, i have some problem,. 1).how to determine bit rate in AMR ??? 2) where i can find algortihm to determine the bit rate of ...

hi, i have some problem,. 1).how to determine bit rate in AMR ??? 2) where i can find algortihm to determine the bit rate of AMR ??? thanks


synchronisation test sequences for GSM speech codecs

Started by ksvd prasad in Speech Coding17 years ago 1 reply

Hi, I'm facing some problem when i'm ensuring bit/frame synchronisation test sequences for GSM speech codecs(HR/EFR/AMR) as...

Hi, I'm facing some problem when i'm ensuring bit/frame synchronisation test sequences for GSM speech codecs(HR/EFR/AMR) as specified by the standard. In the standard also they didn't specify how to test it? if any body works on this please clarify this point. By the way


NAMR test Vectors.

Started by Anonymous in Speech Coding17 years ago

Hi All, Narrow band AMR test vectors (26.074) are in two formats. 1. Bit Stream Format. 2. Parametric (No-Bit Stream) Format....

Hi All, Narrow band AMR test vectors (26.074) are in two formats. 1. Bit Stream Format. 2. Parametric (No-Bit Stream) Format. I have only test vectors for Bit Stream Format. I am in need of test formants in parametric format. Please do the needful.


fixed/algebraic codebook in 3GPP-AMR or G729

Started by Mathew John in Speech Coding17 years ago

Dear all, Can anyone give me/direct me to a DETAILED/any explanation of the fixed codebook(of G729)/algebraic codebook(of 3GPP...

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 to Qk = (x2Hck)^2 (d Ck)^2 (Rk)^2 --------- = ------ = ------- CkH HCk Ck phick Ek ...Equat


AMR LSP quantization

Started by subrata chatterjee in Speech Coding17 years ago 1 reply

hi all, Anybody experienced in AMR speech coding can please tell something about LSP quantization. Actually i have tried to...

hi all, Anybody experienced in AMR speech coding can please tell something about LSP quantization. Actually i have tried to understand it from the standard but i think it's not sufficient. So, please tell me address of any site from where i can collect some informations and