Displaying 20 results from an estimated 4000 matches similar to: "Visualizing echo"
2006 Dec 05
2
problem with echo cancellation
Hello Jean-Marc,
I solved the variable delay problem, but I still have trouble with
speex_echo_cancel(). When i try testecho.c with clean speech for far-end input
and same speech with attenuation, a bit of reverb and 50-150 ms delay, all this
done in sound editor, for mic input, i get 5-8 db attenuation.
But when i use the same speech played and recorded for mic input, i see about 5
db of
2005 Nov 11
4
Re: aec
To everyone on the list: do *NOT* attempt to do echo cancellation with
signals sampled using different clocks. This will *NOT* work. Just a
0.1% difference between the two sampling rates (it's sometimes worse
than that) means that the impulse response drifts by 8 samples every
second. There's just no way to efficiently track this. Or at least no
way that doesn't involve something 100x
2006 May 01
2
Re: speex echo cancellation limitations
> I am writing to gain a better understanding of the limitations of speex echo
> cancellation, esp. with respect to the fixed point implementation.
> If these limitations have been documented elsewhere already, please let me
> know!
Nothing officially documented, sorry.
> I observe experimentally that when one or both of the echo or ref data for
> speex_echo_cancel() have
2009 Jul 06
3
near and talk suppressed
Hi
I have a question about the AEC and preprocessor.
I have seen that when near end is talking for a longer time (about 10 s) without being interrupted
by the far end the residual echo (or rather leak_estimate) increases making the preprocessor
suppress the near end talk when it shouldn't.
Is there a way to make the leakage estimate only update when far-end is present or similar
in order to
2008 Feb 12
0
Second part of data export patch
Hi,
Here are the next two patches for the data export.
speex_get_psd should be applied after speex_get_agc_gain (sent in previous
mail). It allows applications to get the power spectrum for the signal and
the noise estimate.
speex_get_prob should be applied last. It allows fetching the speech
probability of the current frame (the value that the _PROB_START and
_PROB_CONTINUE parameters are
2010 Apr 02
1
lineplot.CI in "sciplot": option "ci.fun" can't be changed?
hi List and Manuel,
I have encounter the following problem with the function "lineplot.CI".? I'm running R 2.10.1, sciplot 1.0-7 on Win XP.? It seems like it's a scoping issue, but I couldn't figure it out.
Thanks!
...Tao
> lineplot.CI(x.factor = dose, response = len, data = ToothGrowth)??? ## fine
> lineplot.CI(x.factor = dose, response = len, data = ToothGrowth,
2011 Feb 10
2
About Sampling Rate Correction in acoustic echo
Thank you, Andreas Engel.
I downloaded the white paper of the Fraunhofer Acoustic Echo Control.
http://www.iis.fraunhofer.de/bf/amm/download/whitepapers/Acoustic_Echo_Control-wp.pdf
It said
> "In the Fraunhofer Acoustic Echo Control, the frequency spectrum of the microphone signal is
> modified so that the undesired echo components are removed from the signal transmitted to
> the
2008 Feb 02
0
Patch to make analysis data available.
Hi,
Ref the disucussion on IRC yesterday; here's a patch which makes a bit
more data from the analysis of the preprocessor and the echo canceller
available.
For the preprocessor:
- Size of power spectrum.
- Power spectrum and noise estimate of the previous frame.
These are given as squared values, so sqrt() to get values in the
0->32767 range.
- Current amplification level
2005 Nov 09
2
Re: aec
I ran some further tests on mdf and here are the
results:
1. reduced tail length to 100ms, aligned mic and
speaker signals to within 10ms - almost no echo
attenuation
2. aligned mic and speaker signals to within 5 samples
- still almost no echo attenuation
3. ran testecho using the same file for mic and
speaker - very good echo cancellation (of course this
is expected, but I needed to do a sanity
2005 Nov 06
2
Re: aec
Thanks for alerting me to the new changes. I just
tried the latest code from SVN, but unfortunately I
still have just about the same results. The estimated
echo that gets subtracted from the actual echo is such
a small signal that it doesn't really result in any
noticeable echo attenuation.
I currently have my filter size set to 2 seconds even
though the echo in my microphone file is only
2005 Jun 20
1
Speech detection in preprocessor with echo
I think you'll have to modify Speex to get the functionality you're
looking for. I've made a few simple modifications to the AGC to prevent
it from 1) exceeding a specified level of amplification and 2) enable
and disable adaptation, so I can freeze it at a certain level while
speech is not detected. It's mostly just a matter of doing this at the
end of speex_compute_agc():
2005 Nov 10
2
Re: aec
Had a try. The reason why a simple delay is not that good is mainly due
to the initialization of the filter parameter that still takes a few
seconds (if they are perfectly in sync, you sort of get lucky).
Otherwise, you real recording seems to have something odd in it. Are you
sampling from a different card then the one that's playing the sound? or
maybe the mic (or something else) in the room
2005 Nov 09
1
Re: aec
I'm pretty much sure of it. When I test inverting the
inputs, my output is pretty much the same as my
speaker signal. Whereas the way that I normally test
the output is my mic signal with very little
attenuation.
If you are interested I can send my test files; they
are about 94KB each.
-Jason
--- Jean-Marc Valin <jean-marc.valin@usherbrooke.ca>
wrote:
> Are you sure you're
2011 Mar 27
0
Help labeling Panels
Hi,
I'm new. I tried to search out this answer but I suspect I was using the
wrong terms, or simply not understanding some of the answers. Anyway here is
my question:
I want to have a 2x2 panel figure with 4 line graphs all in the same scale.
Actually I have that. The thing I seem to be lacking is a way to Label each
panel with a letter. I want it to look something like this:
2005 Mar 18
2
echo / delay problem
I'm having with an echo or delay
I connect to the PSTN with a x100p and then connect a std. phone
to a FXS module on a TDM10B.
The std phone is only 2-wire so I know this is not helping.
(yes I have read the 2-wire 4-wire issue)
I have tried many echocancel values. The best thing to help was
rxgain and txgain. below is my current zapata.conf file
All help would be grateful. I have tried
2008 Sep 22
2
Newbie: Get echo cancellation level
Hi:
I'm using speex to perform echo cancellation in Windows. I'm aware of the problem about out of sync clocks in record and play sample rates in usual sound cards . In order to have an idea of how good is my echo cancelation working I would like to know if there is any #define thing i can pass to speex_echo_ctl to get the actual level of echo cancellation. If not, how can i extract that
2005 Jun 03
1
Speex 1.1.9 is out -- Try the new echo canceller
Hi everyone,
I've just released Speex 1.1.9. The main change in this release is the
echo canceller work sponsored by Tipic Inc (http://www.tipic.com/). It
is now possible to do acoustic echo cancellation and obtain good
attenuation after a short adaptation time. This has been tested at 8
kHz, but it should also work at 16 khz and above, so give it a try.
There were also some fixes to the
2005 Nov 11
2
Re: aec
Le vendredi 11 novembre 2005 ? 01:21 -0800, Duane Storey a ?crit :
> This is a very real problem though.. I've encountered many sound cards that
> use different clocks for input and output (even on the same card!) Also, if
> you open up a sound device on windows at 8kHz, the microphone is often
> around 8100Hz, while the output is 8000Hz.. I'm not sure if there's a bug
>
2008 May 28
2
FFT Resampler
Attached is a snapshot of work-in-progress of a FFT based resampler. At
the moment it works in floating point only, and only basic quality
inspection has been done.
Some benchmarks comparing the filter-based resampler at Q3 with the FFT
resampler with overlap = in_len / 2, using 20ms chunks of data. (-O3
-ffast-math, FFTW3, gcc 4.3.0 on x86_64)
16=>48: 59us vs 19us
16=>44.1: 204us vs
2008 May 29
0
FFT Resampler
On 5/29/08, Thorvald Natvig <thorvald at natvig.com> wrote:
> Alexander Chemeris wrote:
> > On 5/29/08, Thorvald Natvig <thorvald at natvig.com> wrote:
> > > I've done listening tests when converting wb_male.wav to 44.1, 48 and 8khz,
> > > and there aren't any obvious artifacts. I also did a 16=>16 test, and the
> > > results are delayed