6 Apr
2005
6 Apr
'05
10:32 a.m.
Hi!
Are there any tools/libraries around which makes it possible to do
something like this?
1) Feed an audio signal (f.ex. a sinus wave) into external hardware
2) Record the signal returned from the external hardware
3) "Compare" the two signals (realtime would be neat, if you know what
latency you have btwn output/input I hope this might be achieved w
Jack) and perform some kind of analysis of what the external hardware
does to the signal (S/N ratio, damping, etc etc).
Open source stuff would of course be preferable
/Mathias
6 Apr
6 Apr
11 a.m.
On Wed, Apr 06, 2005 at 12:32:20PM +0000, mathias_lundgren(a)bredband.net wrote:
Are there any tools/libraries around which makes it
possible to do
something like this?
1) Feed an audio signal (f.ex. a sinus wave) into external hardware
2) Record the signal returned from the external hardware
3) "Compare" the two signals (realtime would be neat, if you know what
latency you have btwn output/input I hope this might be achieved w
Jack) and perform some kind of analysis of what the external hardware
does to the signal (S/N ratio, damping, etc etc).
You may mave a look at JAAA, (JACK and ALSA Audio Analyser). This is a
realtime 'technical' (rather than musical) spectrum analyser, designed
to make accurate measurements. It will also generate sines and white
Gaussian noise. It's at
<http://users.skynet.be/solaris/linuxadio>
You will also need some small shared libs available from the same
place.
I'm considering some additional functionality, and if you have any
specific requirements I'd be interested to know.
I am also working on a Room Impulse Response measurement system using
a sine sweep as the stimulus. First release expected in a about two
months.
--
FA
11:30 a.m.
On Wed, Apr 06, 2005 at 03:00:45PM +0200, Alfons Adriaensen wrote:
On Wed, Apr 06, 2005 at 12:32:20PM +0000,
mathias_lundgren(a)bredband.net wrote:
> Are there any tools/libraries around which makes it possible to do
> something like this?
>
> 1) Feed an audio signal (f.ex. a sinus wave) into external hardware
>
> 2) Record the signal returned from the external hardware
>
> 3) "Compare" the two signals (realtime would be neat, if you know what
> latency you have btwn output/input I hope this might be achieved w
> Jack) and perform some kind of analysis of what the external hardware
> does to the signal (S/N ratio, damping, etc etc).
in http://whats-your.name/pd/gui/spectrum.gif , the first channel is yellow, the second
channel blue, a notch is swept across the frequency range to demonstrate, the attenuated
area shows in yellow, the equivalent areas in green, the amplified areas in darker
blue..of course the colors are totalyl configurable.
for external hardware youd want to insert a delay between the test signal source and the
graph input, and adjust until it matches the external input to account for system latency
I'm considering some additional functionality, and
if you have any
specific requirements I'd be interested to know.
it would be nice in JAAA to show multiple chans like this, since my 'proof of
concept' is in tcl+tkZinc so it chews about 5% of cpu on my AMD64 and presumably more
on slower hardware..
also, a spectrogram, just for fun ( http://whats-your.name/pd/gui/sp.gif ), and some sort
of RMS with adjustable moving-average length..
carmen
7126
days inactive
7126
days old
linux-audio-dev@lists.linuxaudio.org
2 comments
3 participants
participants (3)
-
Alfons Adriaensen -
carmen -
mathias_lundgrenï¼ bredband.net