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DTMF in G.729

Started by Bob Tausworthe in Speech Coding24 years ago 3 replies

I am reading a spec that states that G.729 is capable of conveying DTMF. Is this correct? I would have thought that G.711 would be...

I am reading a spec that states that G.729 is capable of conveying DTMF. Is this correct? I would have thought that G.711 would be required to accurately code DTMF. thanks in advance Bob Tausworthe


RE: DTMF Decoder

Started by Hocquet Franck in Speech Coding23 years ago

Hi Shahram, As I experienced implementation of very well working DTMF in TI C54x, you can try the following algorithm, which is...

Hi Shahram, As I experienced implementation of very well working DTMF in TI C54x, you can try the following algorithm, which is a part of my decoder. I have it in assembler if you are interested : ;The accumulation of each filter output is endangered by a possible


DTMF Detection

Started by Shehryar Amir in Speech Coding23 years ago 3 replies

Dear All, I am new to this group. I want to implement DTMF Detection algorithm in C/C++. I have read some material on web...

Dear All, I am new to this group. I want to implement DTMF Detection algorithm in C/C++. I have read some material on web and have chosen to start with NonUniform Discrete Fourier Transform i:e Goertzel Algoritm. How can I meet the ITU-T specifiaction ? How can I choose


ANSI specs for DTMF detector

Started by manoj garg in Speech Coding22 years ago

Dear sir, I am searching for the ANSI specifications for the DTMF detector. Could you please tell me where i can get them. ...

Dear sir, I am searching for the ANSI specifications for the DTMF detector. Could you please tell me where i can get them. Are thes specs different from ITU-T AT&T values. How much they diifer? regards manoj


DTMF detection on a GSM AMR bitstream

Started by e_voice61 in Speech Coding21 years ago 2 replies

Hi all, Do anyone know of a way to detect DTMF on a GSM AMR bitstream without fully decoding it? I will be happy to know if...

Hi all, Do anyone know of a way to detect DTMF on a GSM AMR bitstream without fully decoding it? I will be happy to know if you can do it on ITU-T voice codecs as well (G.723.1, G.728, G.729). Thanks


Second Harmincs in speech signal

Started by manoj garg in Speech Coding22 years ago 1 reply

Hello friends, I wanted to know that what is the ratio of second harmonic energy to the fundamental frequency energy in the...

Hello friends, I wanted to know that what is the ratio of second harmonic energy to the fundamental frequency energy in the speech signal. Actually i am implementing a DTMF detector and to discriminate the DTMF signal from the speech i have to put this check.


RE: DTMF Decoder

Started by shahram heidari in Speech Coding23 years ago

Hi Franck Thank you so much for your response. I will appreciate if you send me some part of your code about following ...

Hi Franck Thank you so much for your response. I will appreciate if you send me some part of your code about following topics, if it is possible for you, and also answer me: 1. It is used multiplying factor (1/8) while the number of sample is 16, x(n),...x(n+15).


DTMF Detction

Started by Shehryar Amir in Speech Coding23 years ago

Hi Thanx for your replies. I have gone through a good Article found on web. It says that no single value of "N" can meet...

Hi Thanx for your replies. I have gone through a good Article found on web. It says that no single value of "N" can meet the ITU-T specs and also gave reason for this. That why two values are needed. It has taken N= 106 (13.3msec) for high group and N =212 for


G.711 and G.729a tone detection

Started by Nalin K Pithwa in Speech Coding22 years ago

would G.711u law and G.729a tone detection require any special test equipment just as DTMF tone detection ( like the Bellcore and ...

would G.711u law and G.729a tone detection require any special test equipment just as DTMF tone detection ( like the Bellcore and MITEL tests) ? Regards, NP


VAD/CNG module for GIPS ILBC

Started by navithak in Speech Coding17 years ago 1 reply

Hi, I have implemented Gips ILBC codec on adsp 2185..However I am unable to find any information on the vad/dtx module..Is that royalty...

Hi, I have implemented Gips ILBC codec on adsp 2185..However I am unable to find any information on the vad/dtx module..Is that royalty free as well?? Where can I obtain it?Any information will be greatly appreciated Another question..Does ilbc pass dtmf tone?? regards Navitha


Voice Codecs Algorithms for Pentiums

Started by Mayank Kumar in Speech Coding22 years ago

Hi All, I am involved in a Computer Telephony project and I am looking for Voice Codec algorithms like G.711 (A law and...

Hi All, I am involved in a Computer Telephony project and I am looking for Voice Codec algorithms like G.711 (A law and Ulaw), G.726, G.723.1, G.729a/b, DTMF Generation/Detection, CNG (Comfort Noise Generation), Echo Cancellation, Voice Activity Detection,etc Coded in C