On 07/20/2012 09:48 AM, Eric Wieling wrote:
Neither of your questions relate to T.38 :-) Maybe you meant T.30 instead.
> 1) Does anyone know of any software to debug the g711cap audio files
Asterisk's res_fax generates? Google has not been very helpful.
That will depend a lot on what you mean by 'debug'. We have found them
useful to determine whether the audio path was 'clean' or not. For
example, loading them into Audacity and looking at a spectral plot will
tell you whether there were any extreme spikes, which usually are
indicative of packet loss. You can also use them to look at the timing
of the protocol interactions (delay between transitions between sending
and receiving).
If your goal is to actually demodulate the audio into data and then
interpret the T.30 transactions, I'm not aware of any easily available
tools for doing that. Commetrex (the vendor of the FAX stack in
res_fax_digium) has one that they use for helping to analyze problems,
but I don't believe they make it available outside their company. There
might be something in spandsp, but I haven't looked.
> 2) These files are in WAV format, but my Windows Media Player cannot play
them. The Linux "file" command reports "RIFF (little-endian)
data, WAVE audio, Microsoft PCM, 16 bit, stereo 8000 Hz" Does anyone have
a solution? Is it a bug?
I have never attempted to open them with Windows Media Player, so can't
be of much help there. I know that Audacity will open them and play the
audio properly, because that's what we used when we developed this
'audio capture' feature.
--
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
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