Realtek Mixer as audio input in Audacity

[darius2]

Hi,

I have the following problem.

I call my 3G voice modem connected to laptop and can pick up a call by default app
and can spead to mic of my mobile phone and hear a voice on Realtek's audio out to headphone.

Unfortunately I don't know how to set such data stream as input into Audacity for voice analysis
and DTMF diagnosis.

I set Stereo Mixer as default recording input device ( sound generator).
Unfortunately , selecting monitor input (microphone's icon) in Audacity,
sound from mixer is not sent into Audacity input.

- and no problem with mic input

So I can held a mobile call and sound goes out to headphone but not to Audacity audio input socket.

To analyze DTMF signals from a mobile phone I really need an opportunity to have audio signal to be directed to microphone input in Audacity.

Any idea ?

Darius

[whomper]

use some other hardware and software ?

have you checked out the private investigator sites for such stuff ?

[darius2]

Thanks, problem already solved.
Audacity can read stereo mixer input.

[whomper]

yes audacity can

but not all pcs and soundcards actually have a working stereomix option

hope you catch some spys

[darius2]

Hi,

my interest is in sound quality in Asterisk than in private investigations.

In the same line comes my interest in human voice synthesis for Asterisk, to build human voices on my own, one day.

================

Asterisk Celliax audio recorded by Audiocity in .wav file format

http://www.sendspace.com/file/nk6tb6

=================

Looking for a scripted adaptive, self-learning audio filter app to let me passthrough audio from Asterisk
and get audio stream repaired on-the fly.

Technology supported by Matlab + add-ons.

http://www.google.com/#hl=en&source=hp& ... be010d257f

[whomper]

sounds like a fun project

have you checked what many other university groups have done?

[darius2]

sounds like a fun project

have you checked what many other university groups have done?

===

Natural human voice synthesis is not for fun.
Powerful Microsoft and others can offer a limited number of natural human voices synthesized only.

University r&d groups are really powerful.

Please let me about your experience with natural human voices for Asterisk
and what modules do you prefer or would suggest me for tests.

I have spent few years with Matlab in medical image processing, pattern recognition.


I would greatly appreciate your guidance on adaptive audio filters I can use for repairing sound played by Asterisk ( as above).

Just record audio samples for MOH and use Audacity for spectrum analysis of sound (audio) played by Asterisk via Celliax audio channel ( closed loop environment).

Any help or assistance is welcome.

[whomper]

i looked into this area once
decided it was more than i wanted to take on
especially after i read up on formants

dont remember asterisk

do recall finding a number of places doing similar things
with various approaches

i got interested after i saw software that supposedly would let you sing words that you typed along with music in midi but
they are using samples (i think) not synthesis

dont recall any of them using adaptive filters
but does not mean that none of them are trying that

using existing software means you are limited by what they do
and i dont see many of them doing a good job yet

some places trying to model the throat mouth vocal chords sinuses etc to synthesize but not really good results there yet either

or if there are good results they are still in the lab
but possibly i just didnt find the ones with good results

anyway
searching for what has done should give you ideas
and tell you where the state of the art is for guidance

[darius2]

Thanks again.

Audacity is an excellent tool for basic sound quality testing and analysis.

Just have a look at my Asterisk + Celliax audio quality testing

===

Original DTMF code "111" generated by Audacity , 3 seconds

http://www.filedropper.com/dtmf1113s


The same file played by Asterisk + Celliax
and recorded by Audacity

http://www.filedropper.com/dtmf111s3asterisk

Signal drops has been manually repaired ( select + copy + paste
into no-signal periods)



Please open by Audacity and select
Analyze / Plot Spectrum
from menu

Open 2 above files in 2 instances of Audacity to get a view
of 2 audio spectrums plotted side by side.




==

[darius2]

follow-up

just another test

First audio file is 10 s chirp generated by Audacity and saved as 8000 Hz, 16 bits wav PCM file
to be played as Asterisk's MusicOnHold file

The second audio file is the 1st file played by Asterisk + Celliax and recorded by Audacity.

Look at signal drops

http://www.filedropper.com/chirp10s

http://www.filedropper.com/chirp10sasterisk