re. Poor quality of audio files played by Asterisk via Celliax audio channel to a sound card -> headphone - any idea
The following wav file is audio stream coming from Asterisk, playing standard config files via Celliax audio channel to a sound card, saved in wav audio format by Audiocity.
Asterisk Celliax audio recorded by Audiocity in .wav file format
http://www.sendspace.com/file/nk6tb6
Please play the above wav file and tell me if such audio stream can be repaired by GoldWave to get clear sound, no echo.
I have already contacted developers of Oslec - echo canceller.
Thanks
[e-mail address deleted]
Poor quality of audio files played by Asterisk - any idea
Re: Poor quality of audio files played by Asterisk - any ide
I don't think GoldWave can help you...
I don't hear echo during the talking part, but I think I hear drop-outs. Do you have some echo cancelation enabled? I'm wondering if the drop-outs are the result of over-agressive (or malfunctioning) echo cancelation? I don't believe there is any software that can fix drop-outs... The "data" is missing.
I think I hear echo during the music, but I don't know what the music is supposed to sound like.
I don't know much about echo cancellation... I just know it's very common in telecommunications, and I have a vague idea of how it works... Hopefully someone here knows more than me...*
* You can also try posting your question on the HydrogenAudio.org forum. There is more activity on the Hydrogen Audio forum, and there are people with knowledge in many different audio specialty areas, and with knowledge of various audio software.
I assume you mean Audacity? The tools & features in GoldWave are somewhat similar to Audacity. GoldWave doesn't have an echo cancellation tool, and AFAIK, Audacity doesn't either......recorded by Audiocity...
I don't hear echo during the talking part, but I think I hear drop-outs. Do you have some echo cancelation enabled? I'm wondering if the drop-outs are the result of over-agressive (or malfunctioning) echo cancelation? I don't believe there is any software that can fix drop-outs... The "data" is missing.
I think I hear echo during the music, but I don't know what the music is supposed to sound like.
I don't know much about echo cancellation... I just know it's very common in telecommunications, and I have a vague idea of how it works... Hopefully someone here knows more than me...*
* You can also try posting your question on the HydrogenAudio.org forum. There is more activity on the Hydrogen Audio forum, and there are people with knowledge in many different audio specialty areas, and with knowledge of various audio software.
Re: Poor quality of audio files played by Asterisk - any ide
[misquoted text removed]
==
Thanks DougDbug,
thank you very much for your kind reply.
Sorry for my typo in Audacity.
I have contacted Steve and David, developers of Oslec echo canceller for Linux, ported to Windows.
For echo canceller to work 2 signals should be compared and processed, tx and rx (I suppose so).
In case of recorded audio file or live audio stream to get echo removed,
one have to use pass-through adaptive filter, to let it learn in interactive mode, what echo pattern is ( signal level drop, echo interval or alike ) ( I suppose so).
So your reference to CD, DVD mastering is a good idea, as premastering involvs audio input filtering, processing.
In the meantime I am trying to learn what wav audio formats ( bitrate, frequency, single or dual , mono or stereo)
can Astersk play using its audio codecs
Ok. I have listed Asterisk installed audio codecs with
show audio codes command
as
g723, gsm, ulaw, alaw, g726, adpcm, slin, lpc10 g729, speex, ilbc
but need more detailed specification on wav file format to be played by Asterisk.
Mazzic just responded:
"
Basically the wav files are a mono, 8000Hz sample rate, 64 kbs.
http://wiki.kolmisoft.com/index.php/Con ... ble_format
"
So I am home.
Playing sample audio files ( one frequency peak level) more can be discovered soon about
true reasons staying behind the sound quality.
FFT should generate resonance frequency chart (I suppose so).
thanks
Darius
==
Thanks DougDbug,
thank you very much for your kind reply.
Sorry for my typo in Audacity.
I have contacted Steve and David, developers of Oslec echo canceller for Linux, ported to Windows.
For echo canceller to work 2 signals should be compared and processed, tx and rx (I suppose so).
In case of recorded audio file or live audio stream to get echo removed,
one have to use pass-through adaptive filter, to let it learn in interactive mode, what echo pattern is ( signal level drop, echo interval or alike ) ( I suppose so).
So your reference to CD, DVD mastering is a good idea, as premastering involvs audio input filtering, processing.
In the meantime I am trying to learn what wav audio formats ( bitrate, frequency, single or dual , mono or stereo)
can Astersk play using its audio codecs
Ok. I have listed Asterisk installed audio codecs with
show audio codes command
as
g723, gsm, ulaw, alaw, g726, adpcm, slin, lpc10 g729, speex, ilbc
but need more detailed specification on wav file format to be played by Asterisk.
Mazzic just responded:
"
Basically the wav files are a mono, 8000Hz sample rate, 64 kbs.
http://wiki.kolmisoft.com/index.php/Con ... ble_format
"
So I am home.
Playing sample audio files ( one frequency peak level) more can be discovered soon about
true reasons staying behind the sound quality.
FFT should generate resonance frequency chart (I suppose so).
thanks
Darius
Re: Poor quality of audio files played by Asterisk - any ide
Are you people saying there is nothing which could be done possibly to solve this issue?. I had this same problem and thought it could be rectified somehow.
Regards
Regards
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Re: Poor quality of audio files played by Asterisk - any ide
Echo? Right, there's nothing you can do.Are you people saying there is nothing which could be done possibly to solve this issue?
He's saying that in order to cancel the echo, you need the pure signal without the echo. If the echo is being generated on the phone lines, then it's possible to "capture" the pure signal before the echo gets mixed in. But, that doesn't help us... If we had a file without the echo, we wouldn't have a problem!I have contacted Steve and David, developers of Oslec echo canceller for Linux, ported to Windows.
For echo canceller to work 2 signals should be compared and processed, tx and rx (I suppose so).
A lot of things just can't be fixed. That's why professionals use good equipment and good talent in soundproof studios, and it's why most movie dialog is re-recorded in the studio.
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Re: Poor quality of audio files played by Asterisk - any ide
I believe abhilash is a spammer. His post is vague enough that it could apply to almost any topic. I've deleted the name of the company he is trying to advertise in his signature.
Chris
Chris