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


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


AMR with RTP

Started by Harsha in Speech Coding18 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


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


GSM AMR Ref. C Code analysis

Started by prakash_sebastian in Speech Coding17 years ago

Hi, Can someone who has implemented the reference C code in DSP assembly give me some inputs on: 1. How much of code...

Hi, Can someone who has implemented the reference C code in DSP assembly give me some inputs on: 1. How much of code similarity is there between the 8 bit rates(maybe in terms of percentage)? 2. Is there any code similarity between the Ref. C Code of GSM AMR


NB-AMR seek implementation

Started by Padmanabha V Reddy in Speech Coding8 years ago 3 replies

Hi, I am finding that after seek the output of NB-AMR decoder is distorted. I have observed this behavior with 1. codecs from Google (as...

Hi, I am finding that after seek the output of NB-AMR decoder is distorted. I have observed this behavior with 1. codecs from Google (as part Android), as well as 2. in PC based decoder called AMRPlayer software(For this, I have actually dumped the input given to Google's decoder and fed it to AMRPlayer, thereby I'm simulating the seek but not doing the seek even though it has it). ...


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 IF1 format - how to test?

Started by biswasbiswajit in Speech Coding16 years ago 5 replies

Hi everybody, Can anybody suggest how to test AMR speech in IF1 format? 3GPP reference code has not implemented this (only IF2 is...

Hi everybody, Can anybody suggest how to test AMR speech in IF1 format? 3GPP reference code has not implemented this (only IF2 is implemented). If anybody can point to resources where IF1 decoders are available, it would be of great help. 3gpp standard defines IF1


VAD Decision from G.729B and AMR code

Started by tparis23 in Speech Coding8 years ago

Hello, I am implementing several standard VADs as a reference for my work in my internship on VAD. We've decided on G.729B and AMR. I have...

Hello, I am implementing several standard VADs as a reference for my work in my internship on VAD. We've decided on G.729B and AMR. I have the C code and have read the documentation for the algorithms and for the code, but I seem to be missing something. Where is the VAD speech/non-speech decision output for these programs? Is it in the bitstream, or do I need to modify the code myself ...


Adaptive Codebook generation in AMR speech codec

Started by abhi...@gmail.com in Speech Coding13 years ago

Hi, I am working on a project that implements CELP coding, as in AMR codec for GSM. The codec uses a 'codebook' to store 'code vectors', which...

Hi, I am working on a project that implements CELP coding, as in AMR codec for GSM. The codec uses a 'codebook' to store 'code vectors', which are compared with excitation vectors and the error minimised till a match is found. This match is used to synthesise speech. The spec I am using, 3GPP TS 26.090 ver 6.0.0, r6, specifies codebook architecture but not how it is created. So how is this


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


AMR-fix Point- NB Data rate mismatching

Started by raghus in Speech Coding13 years ago 1 reply

Hi, Plz help me to use AMR Fxd Point NB codec for VoIP application on Pocket PC. Source code is downloaded from 3GPP & Tested with 3GPP...

Hi, Plz help me to use AMR Fxd Point NB codec for VoIP application on Pocket PC. Source code is downloaded from 3GPP & Tested with 3GPP test vector. But its not giving proper output in Device with real time data. But data rate while encoding is 160bytes to 250bytes (increasing) Why is it increasing instead of compressing ?? Where i need to use WB .. ? Plz help to solve this issue ...


abt VAD algorithm 1 of AMR codec

Started by Sameer Kibey in Speech Coding17 years ago

Hi all! i have a query regarding the VAD algorithm 1 used in GSM AMR speech codec.one of the steps in this algo is the use of a...

Hi all! i have a query regarding the VAD algorithm 1 used in GSM AMR speech codec.one of the steps in this algo is the use of a filter bank. this bank consists of 5th and 3rd order filter blocks. for the 3rd order filter block the equations are as follows :


3rd generation of moblie communications :c code ,matlab simulink, matlab s-function and dsp platform for amr encoder and decoder

Started by hoss...@yahoo.com in Speech Coding14 years ago

Hello, I am working on the topic that you see in the subject(3rd generation of moblie communications --> speech coding --> amr (ACELP)...

Hello, I am working on the topic that you see in the subject(3rd generation of moblie communications --> speech coding --> amr (ACELP) encoder and decoder) I have written the c code that is compatible with the needs that we want.and i made it`s decoder and encoder in exe file. now i want to bering it to matlab simulink to make it intarctive. the ne


AMR-WB+

Started by K . Ramakrishna in Speech Coding14 years ago 2 replies

Hi, Is anybody Know about the Internal sampling frequency of the signal what 3gpp guys are using for complexity comparision of AMRWB+? ...

Hi, Is anybody Know about the Internal sampling frequency of the signal what 3gpp guys are using for complexity comparision of AMRWB+? Regards, Rama


Information QCELP13

Started by Nihal Naidu in Speech Coding15 years ago

Hello, Can someone give me some information on QCELP13. I believe it was developed by Qualcomm. Can also someone tell...

Hello, Can someone give me some information on QCELP13. I believe it was developed by Qualcomm. Can also someone tell me how does QCELP13 compare to other speech codecs such as AMR (pros and cons) Thank you. Nihal


doc on G.7XX speech coders

Started by bubu_1212 in Speech Coding16 years ago

Hi I need to get quick view of what is going on in g.7xx and possibly AMR/GSM. Does any one has a good doc to send me? ...

Hi I need to get quick view of what is going on in g.7xx and possibly AMR/GSM. Does any one has a good doc to send me? Thanks bubu


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 =====


Shashi : AMR-NB Optimization

Started by ansh...@tcs.com in Speech Coding14 years ago 2 replies

Shashi, I went thru your posting in response to Venkat's query. What i could make out from your suggestion is this (this is in...

Shashi, I went thru your posting in response to Venkat's query. What i could make out from your suggestion is this (this is in reference to 7.95 Kbps mode; here 4 tracks r used - one non zero pulse from each track; 1st 3 tracks contain 8 positios & the last track contains 16 positions): In the innermost loop : we calculate


Delta SM filter?

Started by "henry.widjaja" in Speech Coding12 years ago

Hi all, In the publication by 3GPP on the noise suppression system for the AMR speech coder (ts_126077v070000p , pg.27), there's a sentence...

Hi all, In the publication by 3GPP on the noise suppression system for the AMR speech coder (ts_126077v070000p , pg.27), there's a sentence that goes like this: "The environmental noise will be Delta SM filtered to incorporate a near field microphone response" What is the 'Delta SM filter'? I tried looking everywhere but I can't find any information about it. Anybody has any ide...