similar to: VAD in asterisk

On Tue, 2003-04-15 at 11:31, Jean-Marc Valin wrote: > > How do i detect whether there is silence in media using speex? > > Is there any API which decides that the audio data only contains > > silence? > > Basically i will have PCM linear data, I want to know whether it is > > complete silence. > > Well, the best way is probably to turn VAD *and*

Jesus, Unfortunately, FFT and magic algorithms don't work (yet?). You might want to try this if you're not satisfied with Speex VAD: http://lists.xiph.org/pipermail/speex-dev/2008-August/006860.html It won't perform any miracles, but I think it works pretty well and is easy to tweak. Tom >---- Original Message ---- >From: jmorion at toomeeting.com >To: speex-dev at

Hello, I am trying to use the preprocessor VAD to encode at lower bitrate during silence periods. I am able to run the preprocessor and get the VAD flag for each frame, and I am quite happy with it's performance. I would like to know how to pass the preprocessor VAD flag to speex encoder -- basically, i want to force the encoder to generate comfort noise when preprocessor detects silence.

Hello! I'm working on adding VAD (silence suppression) to my branch of VOCAL. I've read through the Speex docs and see mentions of VAD/DTX, but I am not sure quite how to use it. For instance, on the transmitter side..do I need to detect the silence somehow and bypass speex encoding, or can speex tell me that the packet is all silent and should not be transmitted as part of it's

Does the Asterisk server support VAD (aka Silence Suppression)? I want my SIP phones (7960's) to use VAD when dialing out the x100P interface. I know the phone can do VAD , can the Asterisk server be setup to do it? and if so, where do I set the configuration? Thanks Lee Goodman -------------- next part -------------- An HTML attachment was scrubbed... URL:

Dear Jean, Thank you so much for reply my message. I am sorry the function return 38 is speex_bits_write(). This function doesn't work on one of my computers. But after I add the function speex_preprocess(), it works well. I am wondering what is the possible reason? What the function speex_preprocess() does? Another problem I have now is when I enable dtx and vad with function

Hello, I run Asterisk in a 100% VOIP installation with the Polycom IP-500 phones. Every once and a while I have problems with either dropped calls between Asterisk and my provider, or invalid RTP audio streams with phones behind NAT. I have had a few Asterisk developers look into my installation and even my provider check my setup but still am having problems. They tell me that I need to

Hello, in my project im using speex 1.2rc1 and the preprocessor VAD seems to only separate complete silence from not complete silence frames. The Speex Manual, you can read "The voice activity detector (VAD) provided by the preprocessor is more advanced than the one directly provided in the codec." but if you go to the source code in preprocess.c line 995 "/* FIXME: This VAD

Hi, When using the encoder function, speex_encode_int(st, in_short, &bits), with VBR disabled and VAD enabled, the function always return a 1. Also, when enabled DTX along with VAD enabled, most of the time the function return a 1 even when it is silence. Is there a way to change the sensitivity of the VAD by changing some parameters in the source code, so when it is silence, the

Hi there, I enable DTX and VAD in speex_encode to detect whether there is silence in voice data. But the same programme got different result on my computers. The function speex_encode always return 38 on one of my computers although it is silence. On all other computers the function speex_encode return 1 when it is silence. It means DTX and VAD doesn't work on particular OS or PC. Do anyone

My data is speech sampled as pcm mono 32khz. I want to use vad for regulating the agc gain mechanism. So... if voice is not detected I just reduce the agc value in order to not amplify the 'silence' otherwise we just increase the agc value if it is below the minimum. Thanks, Daniel ----- Original Message ----- De: Jean-Marc Valin <jean-marc.valin at usherbrooke.ca> Para: danflu at

Hi, My setup is SIP Call-->Asterisk-->VSP1 or VSP2 or VSP3 I'm experiencing an interconnect issue with one of the VSP's that seems to have to do with Asterisk not having any VAD control. The error is: NOTICE[10989]: frame.c:203 __ast_smoother_feed: Dropping extra frame of G.729 since we already have a VAD frame at the end The VSP has switched off silence suppression on their

Hi, My setup is SIP Call-->Asterisk-->VSP1 or VSP2 or VSP3 I'm experiencing an interconnect issue with one of the VSP's that seems to have to do with Asterisk not having any VAD control. The error is: NOTICE[10989]: frame.c:203 __ast_smoother_feed: Dropping extra frame of G.729 since we already have a VAD frame at the end The VSP has switched off silence suppression on

> How do i detect whether there is silence in media using speex? > Is there any API which decides that the audio data only contains > silence? > Basically i will have PCM linear data, I want to know whether it is > complete silence. Well, the best way is probably to turn VAD *and* DTX on. Then when there's silence, the speex_encode function will return zero, which

Hi, I had the same experience. The VAD done in the encoder does not seem to work very well at all. However, the VAD done by speex_preprocess() works much better. You will also get better results if you enable the denoiser, I think. peex_preprocess_ctl(preprocess, SPEEX_PREPROCESS_SET_DENOISE, &denoise_enabled); speex_preprocess_ctl(preprocess, SPEEX_PREPROCESS_SET_VAD,

Hi all, supposing to have speex working at 3.95, when VAD/CNG is employed, which is the size of those "silence" samples respect to voice samples? I am wondering if it could be possible to lower even the transmission of VAD/CNG samples by specifying "outbound" in the communication channel only 1 bit instead of sending the whole VAD/CNG packet. I am doing the same for AMR

Dear Jean, > Actually, 38 is normal for the 15 kbps mode. For the rest, could you > give more details. Also, what platform is the problematic machine? (What > CPU, what OS, what compiler). Thanks for your reply. The platform is WindowsXP Professional with SP1. CPU is Celeron CPU 1.70GHz. Compiler is VC++ 6.0. I have enabled VAD and DTX . In this computer, speex_bits_write() still

> - Is there a reference somewhere (other than the source itself) that > explains how the latest VAD algorithm works? Read the source, Luke :-) (sorry) > - Is it possible to obtain the VAD status of a Speex stream > asynchronously? The current API seems to imply that some kind of > polling is required to determine the voice/non-voice status. Don't understand your question.

you can use the marker bit on the RTP. - farhan On Tue, Aug 19, 2008 at 12:04 PM, Fabio Pietrosanti (naif) <lists at infosecurity.ch> wrote: > Hi all, > > supposing to have speex working at 3.95, when VAD/CNG is employed, which > is the size of those "silence" samples respect to voice samples? > > I am wondering if it could be possible to lower even the

Hello. I have generated a dll out of speex-1.1.4 using VC++6. I did not want all the ogg/wave header in the encoded stream. So I have replaced to codes of speexenc/dec with that of sampleenc/dec from the manual. Thus now the dll accepts the raw input, encodes it and returns the encoded data. I also pass on nbBytes for each frame encoded to the decoder and no other information. I intialise the