Displaying 20 results from an estimated 2000 matches similar to: "how does the echo canceller deal with playback/capture delays?"
2010 Sep 30
2
[SPAM] [BombData][alltestmode] Using Speex Echo Canceller
Hi Anton
Thanks for the info...
What if I use this function do I still need to sync the playback and
capture?
Assuming that the captured voice (*rec) already contains the echo which I
need to cancel out...
--------------------------------
void speex_echo_capture (SpeexEchoState *st, const spx_int16_t *rec,
spx_int16_t *out)
Parameters:
st Echo canceller state
rec signal
2006 Oct 27
2
Echo Canceller trouble in 1.2beta1
Hi Folks,
I am having trouble using speex_echo_cancel. As a starting point, I am
using the testecho.c source code. I compiled the 1.2beta1 version. I
have not tried any other versions of speex.
The document says that the order of arguments to Speex_echo_cancel is
(echo_state, input_frame, echo_frame, output_frame, residue) where
"input_frame" is as captured from mic and
2010 Jul 20
2
[SPAM] [BombData][alltestmode] Re: Speex Echo Cancellation
As for me - speex_echo_cancellation is a better choise. Try using it in
capture thread instead
of those speex_echo_capture and speex_echo_playback functions.
And please, describe your problem in details. Cause the fact that you
"didn get echo cancellation"
doesn't mean you are doing smth wrong.
Regards,
Anton A. Shpakovsky
-----Original Message-----
From: speex-dev-bounces at
2011 Apr 21
3
Acoustic echo cancellation
Simply to say, in a quiet room, you can play a impulse signal and then find it's impulse response signal from the
microphone. For example, if the delay between the impulse signal and its response signal range from 500 to
3000 cycles, you can buffer the far-end signal to 0-300 cycles and set the filter length to 4000. It is also called
to align far-end signal and near-end signal.
BTW: Speex
2012 Aug 26
1
stereo usage of the echo canceler
Hello all.
A few questions on using speex's echo cancellation, for clarifying:
1) I assume that the echo_frame in this method:
speex_echo_playback(echo_state, echo_frame)
is just raw "pcm_s16le" type bits/data? I'm a bit new to all this...
2) I assume from this thread:
http://lists.xiph.org/pipermail/speex-dev/2009-March/007151.html
that speex_echo_playback and
2006 Sep 21
1
echo cancellation causes assertion
Hello,
i'm adding echo cancellation to my voip application, but when i call
speex_echo_capture() or speex_echo_playback() causes an assertion
failed, it seens that there is a delete in any where.
i've encapsulated echo canceller in a class that storage the state and
simply call the functions:
void EchoCanceller::Playback(short *echo_frame)
{
speex_echo_playback(echo_state,
2011 Apr 19
1
Acoustic echo cancellation
>>>> Hi,
>>>
>>> I have a scenario in a mobile VoIP app that requires echo cancellation but
>>> is somewhat different from what's described in the docs.
>>>
>>> Audio is received from and sent to the network at 8000Hz. Each packet
>>> contains 160 samples worth a playback of 20ms.
>>>
>>> But the hardware
2009 Jan 05
2
Echo cancellation and synchronization
Hi Jean-Marc and all others!
I am having some troubles with the echo cancellation feature of speex in
a voip project. I have two threads, one for sound input and one for
sound output.
In the output thread, I call speex_echo_playback(). or every frame sent
to the sound card. In the input thread, I call speex_echo_capture() for
every frame captured from the sound card. Also, I do
2008 Feb 08
1
Echo Canceller on Windows Mobile
Hi Jean Marc,
We are running the speex echo canceller code on a Windows Mobile smartphone using a TI OMAP 201MHz 850. We are making voip calls and audio is working without echo canceller code. Simply adding the following 2 functions whether the echo cancellation is wired in (ie we use the output frame ) or not performance becomes terrible. Note 2 separate threads are used to handle audio.
2009 Mar 11
1
frame_size parameter
Hi Jean,
Thank you for your reply.
Ok... I'm gonna use 'samples per channel' everywhere I see 'samples'...
but what about the 'speex_echo_playback' function ?
it does the following loop:
...
for (i=0;i<st->frame_size;i++)
st->play_buf[st->play_buf_pos+i] = play[i];
...
So... if frame size is 'samples per channel' it will copy only half the
2009 Jun 28
1
TI Davinci DM Serias
Hi, I am attempting to port the speex library to TI Davinci DM35x Family.
My questions are:
1. What is the best ./configure option for it? Is it ARM5e / ARM4 ?
when I tried these two the during the compiled a warning
"I suppose you can have a [ARM4/ARM5E/Blackfin] that has float
instructions?"
2. is there any available demos for the echo cancellation because I can get
it
2009 Sep 29
1
SPEEX_PREPROCESS_SET_ECHO_STATE produces heap corruption
Hi,
when I use preprocessor with AEC, VC++ alerts me about heap corruption.
I have protected speex_echo_playback, speex_echo_capture and
speex_preprocess_run with mutexes, to avoid echo_state being used at the
same time, but it still happens.
Any help about this ussue?
Thank you.
2010 Sep 30
0
[SPAM] [BombData][alltestmode] Re: [SPAM] [BombData][alltestmode] Using Speex Echo Canceller
Hi
So in your case if you don't want to use speex_echo_cancellation than
you should do next way:
Save the playback frames (clean echo) within separate playback thread
with speex_echo_playback func.
Then use speex_echo_capture - it will remove the clean echo frame (saved
with speex_echo_playback func) from
const spx_int16_t *rec buffer (saved with speex_echo_capture) and you
will get
2006 Oct 27
0
Echo Canceller trouble in 1.2beta1
Can you first try the svn version (or apply
https://trac.xiph.org/changeset/11882). As I mentioned in a previous
email, there's a bad bug in the 1.2beta1 echo canceller.
Jean-Marc
Coffey, Michael a ?crit :
> Hi Folks,
>
> I am having trouble using speex_echo_cancel. As a starting point, I am
> using the testecho.c source code. I compiled the 1.2beta1 version. I
> have not
2006 Nov 02
2
echo cancellation on PDA
2006/11/2, Jean-Marc Valin <jean-marc.valin@usherbrooke.ca>:
> > Today I tried speex echo cancellation on my VoIP application running
> > on a windows mobile based PDA (OMAP1510 168MHz). The result is
> > disappointing: it takes 150-250 ms to do echo cancellation (by calling
> > speex_echo_capture() ) for a 20 ms frame!
>
> Are you by any chance using an insane
2010 Jul 15
3
Speex Echo Cancellation
> Message: 1
> Date: Thu, 15 Jul 2010 00:19:43 -0600
> From: devi at purpletalk.com
> Subject: [Speex-dev] Speex Echo Cancellation
> To: speex-dev at xiph.org
> Message-ID: <20100715001943.pr04hvtxsc8k04so at mail.purpletalk.com>
> Content-Type: text/plain; charset=ISO-8859-1; DelSp="Yes";
> format="flowed"
>
> Hi
>
> I am using speex
2010 Sep 29
2
Using Speex Echo Canceller
Hi
Is it possible to use only the speex echo cancellation module w/o using the
speex codec?
Here's the scenario:
1. I have my voice recorded in PCM audio file format
2. I want to cleanup the recorded voice by removing any echo included in the
audio file/buffer
3. can I just use the ff APIs?
- SpeexEchoState* speex_echo_state_init()
- int speex_echo_ctl()
- void speex_echo_capture()
2010 Jul 20
1
[BombData][alltestmode] Re: [SPAM] [BombData][alltestmode] Re: Speex EchoCancellation
Well, I'm not a professional in AEC theory, but what I've mentioned is:
speex_echo_state_init(20, 320*10) - frame size should correspond to
20ms. At your sampling rate (16000hz) is should be 16K*0.02 = 320. The
same I can notice about echo tail. 100ms: 16000*0.3 = 4800, not 3200 as
you has. But that's not crucial I think. Just wanna you get the point.
"Internally,
2006 Oct 27
2
Echo Canceller trouble in 1.2beta1
Terrific! The patch fixes my problem quite decisively.
I will want to use this with a 16K sample rate. Is it expected to work well with just another slight patch, or will we need to modify it more deeply?
Also, are there any tunable parameters besides tail length? I am wondering about the aggressiveness of adaptation and I know you are an expert in that area.
Thanks so much,
Michael
2007 Nov 02
2
Re: Welcome to the "Flac" mailing list
dd if=$file ibs=1 count=$(($(stat --printf='%s' $file)-2)) of=$file.new
of course if you run this on one of the files that doesn't have the
extra 2 bytes
you're gonna lose something you didn't want to
On 11/1/07, Alex Brims <alex.brims@gmail.com> wrote:
> Ok, we actually worked this out - there were 2 extra bytes doing nothing at
> the end of the files. Opening