[Speex-dev] AEC strange behaviour

[hyee wang]

hi, Paul Novodon

Maybe the same question happened to me some yrs ago when I was testing
a PBFDAF AEC filter.

Could you provide me the recorded file to me to study?

Including: the working two files ( far end signal  and  far end echo +
near end signal)
             the not working two files ( far end signal  and  far end
echo + near end signal)

HyeeWang

> ------------------------------
>
> Message: 4
> Date: Tue, 17 Nov 2009 14:56:00 +0600
> From: Pavel Novodon <npd at tomsksoft.com>
> Subject: [Speex-dev] AEC strange behaviour
> To: speex-dev at xiph.org
> Message-ID: <4B026520.2040106 at tomsksoft.com>
> Content-Type: text/plain; charset=windows-1251; format=flowed
>
> Hello.
> I have the following situation. AEC is used in network chat software
> over DirectSound API. Echo and reference signals are almost aligned
> (delay is no more than 30ms). When echo is emulated in notebook
> (built-in speakers + mic) everything goes fine and echo is cancelled.
> But when configuration includes stand-alone speakers and mic no echo is
> removed. Audio is in 22050 hz at 16 bit mono format, number of samples
> to process were 441 and tail was used 4096.
> I've decided to investigate further and took dumps of signals. Buffers
> are aligned, as was said previously, but running testecho.exe doesn't
> produce any noticable echo cancellation. I want to accent on the fact,
> that the same parameters on notebook echo-loop config worked fine. Now
> I'm pretty tired with playing with parameters and buffers and I start
> thinking that the reason may lay in  somewhat audio spectrum or other
> physical/math parameters of samples itself.
> Please, answer whether it is possible or not. I can provide recorded
> dumps so you can test it yourself. This is very crucial situation for
> our software and now we're stuck with it.
>
> Paul Novodon
> Sr. software multimedia developer
> TomskSoft LLC.
>
>
> ------------------------------
>
> _______________________________________________
> Speex-dev mailing list
> Speex-dev at xiph.org
> http://lists.xiph.org/mailman/listinfo/speex-dev
>
>
> End of Speex-dev Digest, Vol 66, Issue 14
> *****************************************
>